001deangelisa.faculty.mjc.edu/class_materials/320 class...MELTEC/MINTEC 320 ELECTRICAL SAFETY Class Material INDEX Controlling Electrical Hazards – OSHA pub 3075 3 OSHA 29 CFR 1910.301

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MELTEC/MINTEC 320 ELECTRICAL SAFETY Class Material INDEX

Controlling Electrical Hazards – OSHA pub 3075 3

OSHA 29 CFR 1910.301 – Subpart S Electrical safety – General industry – Introduction 29

OSHA 29 CFR 1910.302 – Electric utilization systems 31

OSHA 29 CFR 1910.303 – General requirements 37

OSHA 29 CFR 1910.304 – Wiring design and protection 59

OSHA 29 CFR 1910.305 – Wiring methods, components, and equipment for general use 89

OSHA 29 CFR 1910.306 – Specific purpose equipment and installations 115

OSHA 29 CFR 1910.307 – Hazardous (classified) locations 139

OSHA 29 CFR 1910.308 – Special systems 151

OSHA 29 CFR 1910.331 – Electrical safety work practices – Scope 165

OSHA 29 CFR 1910.332 – Training 169

OSHA 29 CFR 1910.333 – Selection and use of work practices 173

OSHA 29 CFR 1910.334 – Use of equipment 187

OSHA 29 CFR 1910.335 – Safeguards for personnel protection 193

OSHA 29 CFR 1910.399 – Definitions applicable to Subpart S 197

OSHA 29 CFR 1910 Subpart S App A – Reference documents for Subpart S 221

Control of Hazardous Energy – OSHA pub 3120 225

OSHA 29 CFR 1910.147 – The control of hazardous energy 253

Standard interpretations – Grounding requirements for equipment connected by cord and plug 281

Standard interpretations – Fixed wiring in research facilities and high voltage cable tray sys. 285

Small Business Handbook – OSHA pub 2209–02R 291

Personal Protective Equipment – OSHA pub 3151–12R 347

Ground fault protection in construction sites – OSHA pub 3007 393

NIOSH – Electrical Safety (Student Manual) 411

OSHA Pocket Guide – Worker Safety Series – Construction Industry – OSHA pub 3252–05N 499

OSHA Fact Sheets – Electrical Safety Hazards of Overloading Cable Trays 535

OSHA Fact Sheets – Working Safely Around Downed Electrical Wires 537

Quiz # 1 539

Quiz # 2 543

Quiz # 3 549

Quiz # 4 555

Quiz # 5 557

Quiz # 6 565

Quiz # 7 579

Quiz # 8 583

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Contents

Introduction .............................................................. 1

Why should you be concerned aboutelectrical hazards? ........................................................... 2

What OSHA standards address electrical safety? .............. 3

How do OSHA’s standards minimizeelectrical hazards? ........................................................... 4

Electricity: The Basics ..............................................5

What affects the flow of electricity? ............................. 5

How does water affect the flow of electricity? ............... 5

What causes shocks? ................................................. 5

What effect do shocks have on the body? .................... 6

What kind of burns can a shock cause? ....................... 8

Why do people sometimes “freeze” whenthey are shocked? ...................................................... 8

What should you do if someone “freezes”to a live electrical contact? .......................................... 9

How can you tell if a shock is serious? ......................... 9

What is the danger of static electricity? ...................... 10

Protection Against Electrical Hazards ..................... 11

What is the best way to protect yourselfagainst electrical hazards? ........................................ 11

What protection does insulation provide? .................. 11

How do you identify different types of insulation? ....... 11

What is guarding and what protectiondoes it offer? ........................................................... 12

What is grounding and what protectiondoes it offer? ........................................................... 13

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What are circuit protection devices andhow do they work? ................................................... 14

What work practices help protect youagainst electrical hazards? ........................................ 15

How can you protect yourself againstmetal parts that become energized? .......................... 15

How can you prevent an accidental orunexpected equipment startup? ................................ 16

How can you protect yourself fromoverhead power lines? ............................................. 17

What protection does personal equipment offer? ....... 18

What role do tools play? ........................................... 18

What special training do employees need? ................ 18

What’s the value of a safety and health programin controlling electrical hazards? ................................ 19

How Can OSHA Help Me? ...................................... 20

How does safety and health program managementassistance help employers and employees? ............... 20

What are state plans? .............................................. 21

How can consultation assistance help employers? ....... 21

Who can get consultation assistanceand what does it cost? .............................................. 22

Can OSHA assure privacy to an employerwho asks for consultation assistance? ........................ 22

Can an employer be cited for violationsafter receiving consultation assistance? ...................... 22

Does OSHA provide any incentives forseeking consultation assistance? ................................ 23

What is the Voluntary Protection Program? ................ 23

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How does the Voluntary Protection Program work? .... 24

How does VPP help employers and employees? ........ 24

How does OSHA monitor VPP sites? ........................ 25

Can OSHA inspect an employer whois participating in the VPP? ....................................... 25

How can a partnership with OSHA improveworker safety and health? ......................................... 25

What is OSHA’s Strategic PartnershipProgram (OSPP)? ................................................... 26

What do OSPPs do? ............................................... 26

Are there different kinds of OSPPs? ......................... 26

What are the benefits of participation inthe OSPP? .............................................................. 27

Does OSHA have occupational safety andhealth training for employers and employees? ............ 28

Does OSHA give money to organizationsfor training and education? ....................................... 29

Does OSHA have other assistancematerials available? .................................................. 30

What do I do in case of an emergency?Or if I need to file a complaint? ................................. 30

OSHA Offices ......................................................... 31

Regional Offices ....................................................... 31

Area Offices ............................................................ 33

State and Territories withOSHA-Approved Safety and Health Plans ................ 48

OSHA Onsite Consultation Offices ............................ 54

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Introduction

This booklet provides an overview of basic electricalsafety on the job.

Electricity is essential to modern life, both athome and on the job. Some employees — engineers,electricians, electronic technicians, and power lineworkers, among them — work with electricity directly.Others, such as office workers and sales people, workwith it indirectly. Perhaps because it has become sucha familiar part of our daily life, many of us don’t givemuch thought to how much our work depends on areliable source of electricity. More importantly, wetend to overlook the hazards electricity poses and failto treat it with the respect it deserves.

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Why should you be concernedabout electrical hazards?

Electricity has long been recognized as a seriousworkplace hazard, exposing employees to electric shock,electrocution, burns, fires, and explosions. In 1999, forexample, 278 workers died from electrocutions at work,accounting for almost 5 percent of all on-the-job fatalitiesthat year, according to the Bureau of Labor Statistics.What makes these statistics more tragic is that most ofthese fatalities could have been easily avoided.

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What OSHA standardsaddress electrical safety?

OSHA standards cover many electrical hazards in manydifferent industries. OSHA’s general industry electricalsafety standards are published in Title 29 Code of FederalRegulations (CFR), Part 1910.302 through 1910.308 —Design Safety Standards for Electrical Systems, and1910.331 through 1910.335 — Electrical Safety-RelatedWork Practices Standards.

OSHA’s electrical standards are based on theNational Fire Protection Association Standards NFPA 70,National Electric Code, and NFPA 70E, ElectricalSafety Requirements for Employee Workplaces.

OSHA also has electrical safety standards for theconstruction industry, in 29 CFR 1926, Subpart K. OSHA’sstandards for marine terminals, in 29 CFR 1917, and forlongshoring, in 29 CFR 1918, reference the general industryelectrical standards in Subpart S of Part 1910. The shipyardstandards, in 29 CFR 1915, cover limited electrical safetywork practices in 29 CFR 1915.181.

Although OSHA operates a federal occupational safetyand health program, 24 states and 2 territories operatetheir own OSHA-approved programs. In those states, thestandards and other procedures governing electrical safetymay not be identical to the federal requirements. They must,however, be at least as effective as the federal standards.

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How do OSHA’s standardsminimize electrical hazards?

OSHA standards focus on the design and use of electricalequipment and systems. The standards cover only theexposed or operating elements of an electrical installationsuch as lighting, equipment, motors, machines, appliances,switches, controls, and enclosures, requiring that they beconstructed and installed to minimize workplace electricaldangers. Also, the standards require that certain approvedtesting organizations test and certify electrical equipmentbefore use in the workplace to ensure it is safe.

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Electricity: The Basics

What affects the flow of electricity?

Electricity flows more easily through some materials thanothers. Some substances such as metals generally offer verylittle resistance to the flow of electric current and are called“conductors.” A common but perhaps overlooked conductoris the surface or subsurface of the earth. Glass, plastic,porcelain, clay, pottery, dry wood, and similar substancesgenerally slow or stop the flow of electricity. They are called“insulators.” Even air, normally an insulator, can become aconductor, as occurs during an arc or lightning stroke.

How does water affect theflow of electricity?

Pure water is a poor conductor. But small amounts ofimpurities in water like salt, acid, solvents, or other materialscan turn water itself and substances that generally act asinsulators into conductors or better conductors. Dry wood,for example, generally slows or stops the flow of electricity.But when saturated with water, wood turns into a conductor.The same is true of human skin. Dry skin has a fairly highresistance to electric current. But when skin is moist or wet,it acts as a conductor. This means that anyone working withelectricity in a damp or wet environment needs to exerciseextra caution to prevent electrical hazards.

What causes shocks?

Electricity travels in closed circuits, normally through aconductor. But sometimes a person’s body — an efficientconductor of electricity — mistakenly becomes part of the

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electric circuit. This can cause an electrical shock. Shocksoccur when a person’s body completes the current path with:

• both wires of an electric circuit;• one wire of an energized circuit and the ground;

• a metal part that accidentally becomes energized due,for example, to a break in its insulation; or

• another “conductor” that is carrying a current.

When a person receives a shock, electricity flows betweenparts of the body or through the body to a ground or theearth.

What effect do shocks haveon the body?

An electric shock can result in anything from a slighttingling sensation to immediate cardiac arrest. The severitydepends on the following:

• the amount of current flowing through the body,

• the current’s path through the body,

• the length of time the body remains in the circuit, and

• the current’s frequency.

This table shows the general relationship between theamount of current received and the reaction when currentflows from the hand to the foot for just 1 second.

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Effects of Electric Current in the Human Body

Current Reaction

Below 1 milliampere Generally not perceptible

1 milliampere Faint tingle

5 milliamperes Slight shock felt; not painful butdisturbing. Average individual canlet go. Strong involuntary reactionscan lead to other injuries.

6–25 milliamperes (women) Painful shock, loss of muscularcontrol*

9–30 milliamperes (men) The freezing current or “let-go”range.* Individual cannot let go,but can be thrown away from thecircuit if extensor muscles arestimulated.

50–150 milliamperes Extreme pain, respiratory arrest,severe muscular contractions.Death is possible.

1,000–4,300 milliamperes Rhythmic pumping action ofthe heart ceases. Muscularcontraction and nerve damageoccur; death likely.

10,000 milliamperes Cardiac arrest, severe burns; deathprobable

* If the extensor muscles are excited by the shock, the personmay be thrown away from the power source.

Source: W.B. Kouwenhoven, “Human Safety and Electric Shock,”Electrical Safety Practices, Monograph, 112, InstrumentSociety of America, p. 93. November 1968.

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What kind of burns can a shock cause?

Burns are the most common shock-related injury.An electrical accident can result in an electrical burn,arc burn, thermal contact burn, or a combination of burns.

Electrical burns are among the most serious burns andrequire immediate medical attention. They occur whenelectric current flows through tissues or bone, generatingheat that causes tissue damage.

Arc or flash burns result from high temperatures causedby an electric arc or explosion near the body. These burnsshould be treated promptly.

Thermal contact burns are caused when the skin toucheshot surfaces of overheated electric conductors, conduits,or other energized equipment. Thermal burns also can becaused when clothing catches on fire, as may occur whenan electric arc is produced.

In addition to shock and burn hazards, electricity posesother dangers. For example, arcs that result from shortcircuits can cause injury or start a fire. Extremely high-energyarcs can damage equipment, causing fragmented metal tofly in all directions. Even low-energy arcs can cause violentexplosions in atmospheres that contain flammable gases,vapors, or combustible dusts.

Why do people sometimes “freeze”when they are shocked?

When a person receives an electrical shock, sometimesthe electrical stimulation causes the muscles to contract.This “freezing” effect makes the person unable to pull freeof the circuit. It is extremely dangerous because it increasesthe length of exposure to electricity and because the currentcauses blisters, which reduce the body’s resistance andincreases the current.

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The longer the exposure, the greater the risk of seriousinjury. Longer exposures at even relatively low voltages canbe just as dangerous as short exposures at higher voltages.Low voltage does not imply low hazard.

In addition to muscle contractions that cause “freezing,”electrical shocks also can cause involuntary muscle reactions.These reactions can result in a wide range of other injuriesfrom collisions or falls, including bruises, bone fractures, andeven death.

What should you do if someone“freezes” to a live electrical contact?

If a person is “frozen” to a live electrical contact, shut offthe current immediately. If this is not possible, use boards,poles, or sticks made of wood or any other nonconductingmaterials and safely push or pull the person away from thecontact. It’s important to act quickly, but remember to protectyourself as well from electrocution or shock.

How can you tell if a shock is serious?

A severe shock can cause considerably more damage thanmeets the eye. A victim may suffer internal hemorrhages anddestruction of tissues, nerves, and muscles that aren’t readilyvisible. Renal damage also can occur. If you or a coworkerreceives a shock, seek emergency medical help immediately.

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What is the danger of static electricity?

Static electricity also can cause a shock, though in adifferent way and generally not as potentially severe asthe type of shock described previously. Static electricity canbuild up on the surface of an object and, under the rightconditions, can discharge to a person, causing a shock.The most familiar example of this is when a person reachesfor a door knob or other metal object on a cold, relativelydry day and receives a shock.

However, static electricity also can cause shocks or can justdischarge to an object with much more serious consequences,as when friction causes a high level of static electricity tobuild up at a specific spot on an object. This can happensimply through handling plastic pipes and materials orduring normal operation of rubberized drive or machine beltsfound in many worksites. In these cases, for example, staticelectricity can potentially discharge when sufficient amountsof flammable or combustible substances are located nearbyand cause an explosion. Grounding or other measures maybe necessary to prevent this static electricity buildup andthe results.

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Protection AgainstElectrical Hazards

What is the best way to protectyourself against electrical hazards?

Most electrical accidents result from one of the followingthree factors:

• unsafe equipment or installation,

• unsafe environment, or

• unsafe work practices.

Some ways to prevent these accidents are through theuse of insulation, guarding, grounding, electrical protectivedevices, and safe work practices.

What protection does insulationprovide?

Insulators such as glass, mica, rubber, or plastic used tocoat metals and other conductors help stop or reduce theflow of electrical current. This helps prevent shock, fires, andshort circuits. To be effective, the insulation must be suitablefor the voltage used and conditions such as temperatureand other environmental factors like moisture, oil, gasoline,corrosive fumes, or other substances that could cause theinsulator to fail.

How do you identify differenttypes of insulation?

Insulation on conductors is often color coded. Insulatedequipment grounding conductors usually are either solidgreen or green with yellow stripes. Insulation coveringgrounded conductors is generally white or gray. Ungroundedconductors, or “hot wires,” often are black or red, althoughthey may be any color other than green, white, or gray.

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Before connecting electrical equipment to a power source,it’s a good idea to check the insulation for any exposed wiresfor possible defects. Insulation covering flexible cords suchas extension cords is particularly vulnerable to damage.

The insulation that covers conductors in non-constructionapplications is regulated by Subpart S of 29 CFR 1910.302through 1910.308, Wiring Design and Protection.Subpart S generally requires insulation on circuit conductors.It also specifies that the insulation used should be suitablefor the voltage and conditions. Conductors used inconstruction applications are regulated by Subpart K of29 CFR 1926.402 through 1926.408.

What is guarding and whatprotection does it offer?

Guarding involves locating or enclosing electric equipmentto make sure people don’t accidentally come into contactwith its live parts. Effective guarding requires equipmentwith exposed parts operating at 50 volts or more to beplaced where it is accessible only to authorized peoplequalified to work with it. Recommended locations are aroom, vault, or similar enclosure; a balcony, gallery, orelevated platform; or a site elevated 8 feet (2.44 meters)or more above the floor. Sturdy, permanent screens alsocan serve as effective guards.

Conspicuous signs must be posted at the entrances toelectrical rooms and similarly guarded locations to alertpeople to the electrical hazard and to forbid entry tounauthorized people. Signs may contain the word “Danger,”“Warning,” or “Caution,” and beneath that, appropriateconcise wording that alerts people to the hazard or givesan instruction, such as “Danger/High Voltage/Keep Out.”

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What is grounding and whatprotection does it offer?

“Grounding” a tool or electrical system means intentionallycreating a low-resistance path that connects to the earth.This prevents the buildup of voltages that could cause anelectrical accident.

Grounding is normally a secondary protective measureto protect against electric shock. It does not guarantee thatyou won’t get a shock or be injured or killed by an electricalcurrent. It will, however, substantially reduce the risk,especially when used in combination with other safetymeasures discussed in this booklet.

29 CFR, Part 1910.304, Subpart S, Wiring Designand Protection, requires at times a service or system groundand an equipment ground in non-construction applications.

A service or system ground is designed primarily toprotect machines, tools, and insulation against damage.One wire, called the “neutral” or “grounded” conductor,is grounded. In an ordinary low-voltage circuit, the whiteor gray wire is grounded at the generator or transformerand at the building’s service entrance.

An equipment ground helps protect the equipmentoperator. It furnishes a second path for the current topass through from the tool or machine to the ground.This additional ground safeguards the operator if amalfunction causes the tool’s metal frame to becomeenergized. The resulting flow of current may activate thecircuit protection devices.

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What are circuit protection devicesand how do they work?

Circuit protection devices limit or stop the flow of currentautomatically in the event of a ground fault, overload, or shortcircuit in the wiring system. Well-known examples of thesedevices are fuses, circuit breakers, ground-fault circuitinterrupters, and arc-fault circuit interrupters.

Fuses and circuit breakers open or break the circuitautomatically when too much current flows through them.When that happens, fuses melt and circuit breakers tripthe circuit open. Fuses and circuit breakers are designed toprotect conductors and equipment. They prevent wires andother components from overheating and open the circuitwhen there is a risk of a ground fault.

Ground-fault circuit interrupters, or GFCIs, are used inwet locations, construction sites, and other high-risk areas.These devices interrupt the flow of electricity within aslittle as 1/40 of a second to prevent electrocution. GFCIscompare the amount of current going into electric equipmentwith the amount of current returning from it along the circuitconductors. If the difference exceeds 5 milliamperes, thedevice automatically shuts off the electric power.

Arc-fault devices provide protection from the effects ofarc-faults by recognizing characteristics unique to arcing andby functioning to deenergize the circuit when an arc-faultis detected.

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What work practices help protectyou against electrical hazards?

Electrical accidents are largely preventable throughsafe work practices. Examples of these practices includethe following:

• deenergizing electric equipment before inspectionor repair,

• keeping electric tools properly maintained,

• exercising caution when working near energized lines,and

• using appropriate protective equipment.

Electrical safety-related work practice requirementsfor general industry are detailed in Subpart S of 29 CFRPart 1910, in Sections 1910.331–1910.335. Forconstruction applications, electrical safety-related workpractice requirements are detailed in Subpart K of29 CFR Part 1926.416 to 1926.417.

How can you protect yourself againstmetal parts that become energized?

A break in an electric tool’s or machine’s insulation cancause its metal parts to become “hot” or energized, meaningthat they conduct electricity. Touching these energized partscan result in an electrical shock, burn, or electrocution. Thebest way to protect yourself when using electrical tools ormachines is to establish a low-resistance path from the device’smetallic case to the ground. This requires an equipmentgrounding conductor, a low-resistance wire that directsunwanted current directly to the ground. A properly installedgrounding conductor has a low resistance to ground and greatlyreduces the amount of current that passes through your body.Cord and plug equipment with a three-prong plug is a commonexample of equipment incorporating this ground conductor.

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Another form of protection is to use listed or labeledportable tools and appliances protected by an approvedsystem of double insulation or its equivalent. Where sucha system is employed, it must be marked distinctively toindicate that the tool or appliance uses an approved doubleinsulation system.

How can you prevent an accidentalor unexpected equipment startup?

Proper lockout/tagout procedures protect you from thedangers of the accidental or unexpected startup of electricalequipment and are required for general industry by OSHAStandard 1910.333, Selection and Use of Work Practices.Requirements for construction applications are in 29 CFR1926.417, Lockout and Tagging of Circuits. These proceduresensure that electrical equipment is deenergized before it isrepaired or inspected and protects you against electrocutionor shock.

The first step before beginning any inspection or repair jobis to turn the current off at the switch box and padlock theswitch in the OFF position. This applies even on so-calledlow-voltage circuits. Securely tagging the switch or controlsof the machine or equipment being locked out of serviceclarifies to everyone in the area which equipment or circuitsare being inspected or repaired.

Only qualified electricians who have been trained in safelockout procedures should maintain electrical equipment.No two of the locks used should match, and each key shouldfit just one lock. In addition, one individual lock and keyshould be issued to each maintenance worker authorized tolock out and tag the equipment. All employees who repair agiven piece of equipment should lock out its switch with anindividual lock. Only authorized workers should be permittedto remove it.

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How can you protect yourself fromoverhead power lines?

Before working under or near overhead power lines,ensure that you maintain a safe distance to the lines and,for very high-voltage lines, ground any equipment such ascranes that can become energized. If working on power lines,ensure that the lines have been deenergized and groundedby the owner or operator of the lines. Other protectivemeasures like guarding or insulating the lines help preventaccidental contact.

Employees unqualified to work with electricity, as wellas mechanical equipment, should remain at least 10 feet(3.05 meters) away from overhead power lines. If the voltageis more than 50,000 volts, the clearance increases by 4 inches(10 centimeters) for each additional 10,000 volts.

When mechanical equipment is operated near overheadlines, employees standing on the ground should avoid contactwith the equipment unless it is located outside the dangerzone. When factoring the safe standoff distance, be sure toconsider the equipment’s maximum reach.

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What protection does personalequipment offer?

Employees who work directly with electricity should usethe personal protective equipment required for the jobs theyperform. This equipment may include rubber insulatinggloves, hoods, sleeves, matting, blankets, line hose, andindustrial protective helmets designed to reduce electricshock hazard. All help reduce the risk of electrical accidents.

What role do tools play?

Appropriate and properly maintained tools help protectworkers against electric hazards. It’s important to maintaintools regularly because it prevents them from deterioratingand becoming dangerous. Check each tool before using it. Ifyou find a defect, immediately remove it from service and tagit so no one will use it until it has been repaired or replaced.

When using a tool to handle energized conductors, checkto make sure it is designed and constructed to withstand thevoltages and stresses to which it has been exposed.

What special training doemployees need?

All employees should be trained to be thoroughly familiarwith the safety procedures for their particular jobs. Moreover,good judgment and common sense are integral to preventingelectrical accidents. When working on electrical equipment,for example, some basic procedures to follow are to:

• deenergize the equipment,

• use lockout and tag procedures to ensure that theequipment remains deenergized,

• use insulating protective equipment, and

• maintain a safe distance from energized parts.

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What’s the value of a safety and healthprogram in controlling electrical hazards?

Every good safety and health program provides measuresto control electrical hazards. The measures suggested in thisbooklet should be helpful in establishing such a program.The responsibility for this program should be delegated tosomeone with a complete knowledge of electricity, electricalwork practices, and the appropriate OSHA standards forinstallation and performance.

Everyone has the right to work in a safe environment.Safety and health add value to your business and yourworkplace. Through cooperative efforts, employers andemployees can learn to identify and eliminate or controlelectrical hazards.

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Regulations (Standards - 29 CFR)

Introduction. - 1910.301

This subpart addresses electrical safety requirements that are necessary for the practical

safeguarding of employees in their workplaces and is divided into four major divisions as

follows:

1910.301(a)

Design safety standards for electrical systems. These regulations are contained in

1910.302 through 1910.330. Sections 1910.302 through 1910.308 contain design safety

standards for electric utilization systems. Included in this category are all electric

equipment and installations used to provide electric power and light for employee

workplaces. Sections 1910.309 through 1910.330 are reserved for possible future design

safety standards for other electrical systems.

1910.301(b)

Safety-related work practices. These regulations will be contained in 1910.331 through

1910.360.

1910.301(c)

Safety-related maintenance requirements. These regulations will be contained in

1910.361 through 1910.380.

• Part Number: 1910

• Part Title: Occupational Safety and Health Standards

• Subpart: S

• Subpart Title: Electrical

• Standard Number: 1910.301

• Title: Introduction.

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1910.301(d)

Safety requirements for special equipment. These regulations will be contained in

1910.381 through 1910.398.

1910.301(e)

Definitions. Definitions applicable to each division are contained in 1910.399.

[46 FR 4056, Jan. 16, 1982; 46 FR 40185, Aug. 7, 1981]

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Electric utilization systems. - 1910.302



• Subpart: S



• Title: Electric utilization systems.

Sections 1910.302 through 1910.308 contain design safety standards for electric

utilization systems. 1910.302(a)

Scope --

1910.302(a)(1)

Covered. The provisions of §§ 1910.302 through 1910.308 cover electrical installations

and utilization equipment installed or used within or on buildings, structures, and other

premises, including:

1910.302(a)(1)(i)

Yards;

1910.302(a)(1)(ii)

Carnivals;

1910.302(a)(1)(iii)

Parking and other lots;

1910.302(a)(1)(iv)

Mobile homes;

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1910.302(a)(1)(v)

Recreational vehicles;

1910.302(a)(1)(vi)

Industrial substations;

1910.302(a)(1)(vii)

Conductors that connect the installations to a supply of electricity; and

1910.302(a)(1)(viii)

Other outside conductors on the premises.

1910.302(a)(2)

Not covered. The provisions of §§ 1910.302 through 1910.308 do not cover:

1910.302(a)(2)(i)

Installations in ships, watercraft, railway rolling stock, aircraft, or automotive vehicles

other than mobile homes and recreational vehicles;

1910.302(a)(2)(ii)

Installations underground in mines;

1910.302(a)(2)(iii)

Installations of railways for generation, transformation, transmission, or distribution of

power used exclusively for operation of rolling stock or installations used exclusively for

signaling and communication purposes;

1910.302(a)(2)(iv)

Installations of communication equipment under the exclusive control of communication

utilities, located outdoors or in building spaces used exclusively for such installations; or.

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1910.302(a)(2)(v)

Installations under the exclusive control of electric utilities for the purpose of

communication or metering; or for the generation, control, transformation, transmission,

and distribution of electric energy located in buildings used exclusively by utilities for

such purposes or located outdoors on property owned or leased by the utility or on public

highways, streets, roads, etc., or outdoors by established rights on private property.

1910.302(b)

Extent of application --

1910.302(b)(1)

Requirements applicable to all installations. The following requirements apply to all

electrical installations and utilization equipment, regardless of when they were designed

or installed:

§ 1910.303(b) -- Examination, installation, and use of equipment

§ 1910.303(c)(3) -- Electrical connections -- Splices

§ 1910.303(d) -- Arcing parts

§ 1910.303(e) -- Marking

§ 1910.303(f), except (f)(4) and (f)(5) -- Disconnecting means and circuits

§ 1910.303(g)(2) -- 600 volts or less -- Guarding of live parts

§ 1910.304(a)(3) -- Use of grounding terminals and devices

§ 1910.304(f)(1)(i), (f)(1)(iv), and (f)(1)(v) -- Overcurrent protection -- 600 volts,

nominal, or less

§ 1910.304(g)(1)(ii), (g)(1)(iii), (g)(1)(iv), and (g)(1)(v) -- Grounding -- Systems to be

grounded

§ 1910.304(g)(4) -- Grounding -- Grounding connections

§ 1910.304(g)(5) -- Grounding -- Grounding path

§ 1910.304(g)(6)(iv)(A) through (g)(6)(iv)(D), and (g)(6)(vi) -- Grounding -- Supports,

enclosures, and equipment to be grounded

§ 1910.304(g)(7) -- Grounding -- Nonelectrical equipment

§ 1910.304(g)(8)(i) -- Grounding -- Methods of grounding fixed equipment

§ 1910.305(g)(1) -- Flexible cords and cables--Use of flexible cords and cables

§ 1910.305(g)(2)(ii) and (g)(2)(iii) -- Flexible cords and cables -- Identification, splices,

and terminations

§ 1910.307, except as specified in § 1910.307(b) -- Hazardous (classified) locations

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1910.302(b)(2)

Requirements applicable to installations made after March 15, 1972. Every electrical

installation and all utilization equipment installed or overhauled after March 15, 1972,

shall comply with the provisions of §§ 1910.302 through 1910.308, except as noted in

paragraphs (b)(3) and (b)(4) of this section.

1910.302(b)(3)

Requirements applicable only to installations made after April 16, 1981. The following

requirements apply only to electrical installations and utilization equipment installed after

April 16, 1981:

§ 1910.303(h)(4) -- Over 600 volts, nominal -- Entrance and access to work space

§ 1910.304(f)(1)(vii) and (f)(1)(viii) -- Overcurrent protection -- 600 volts, nominal, or

less

§ 1910.304(g)(9)(i) -- Grounding -- Grounding of systems and circuits of 1000 volts and

over (high voltage)

§ 1910.305(j)(6)(ii)(D) -- Equipment for general use -- Capacitors

§ 1910.306(c)(9) -- Elevators, dumbwaiters, escalators, moving walks, wheelchair lifts,

and stairway chair lifts -- Interconnection between multicar controllers

§ 1910.306(i) -- Electrically driven or controlled irrigation machines

§ 1910.306(j)(5) -- Swimming pools, fountains, and similar installations -- Fountains

§ 1910.308(a)(1)(ii) -- Systems over 600 volts, nominal -- Aboveground wiring methods

§ 1910.308(c)(2) -- Class 1, Class 2, and Class 3 remote control, signaling, and power-

limited circuits -- Marking

§ 1910.308(d) -- Fire alarm systems

1910.302(b)(4)

Requirements applicable only to installations made after August 13, 2007. The following

requirements apply only to electrical installations and utilization equipment installed after

August 13, 2007:

§ 1910.303(f)(4) -- Disconnecting means and circuits -- Capable of accepting a lock

§ 1910.303(f)(5) -- Disconnecting means and circuits -- Marking for series combination

ratings

§ 1910.303(g)(1)(iv) and (g)(1)(vii) -- 600 Volts, nominal, or less -- Space about electric

equipment

§ 1910.303(h)(5)(vi) -- Over 600 volts, nominal -- Working space and guarding

§ 1910.304(b)(1) -- Branch circuits -- Identification of multiwire branch circuits

034

§ 1910.304(b)(3)(i) -- Branch circuits -- Ground-fault circuit interrupter protection for

personnel

§ 1910.304(f)(2)(i)(A), (f)(2)(i)(B) (but not the introductory text to § 1910.304(f)(2)(i)),

and (f)(2)(iv)(A) -- Overcurrent protection -- Feeders and branch circuits over 600 volts,

nominal

§ 1910.305(c)(3)(ii) -- Switches -- Connection of switches

§ 1910.305(c)(5) -- Switches -- Grounding

§ 1910.306(a)(1)(ii) -- Electric signs and outline lighting -- Disconnecting means


and stairway chair lifts -- Operation


and stairway chair lifts -- Location


and stairway chair lifts -- Identification and signs


and stairway chair lifts -- Single-car and multicar installations

§ 1910.306(j)(1)(iii) -- Swimming pools, fountains, and similar installations --

Receptacles

§ 1910.306(k) -- Carnivals, circuses, fairs, and similar events

§ 1910.308(a)(5)(v) and (a)(5)(vi)(B) -- Systems over 600 volts, nominal -- Interrupting

and isolating devices

§ 1910.308(a)(7)(vi) -- Systems over 600 volts, nominal -- Tunnel installations

§ 1910.308(b)(3) -- Emergency power systems -- Signs

§ 1910.308(c)(3) -- Class 1, Class 2, and Class 3 remote control, signaling, and power-

limited circuits -- Separation from conductors of other circuits

§ 1910.308(f) -- Solar photovoltaic systems

1910.302(c)

Applicability of requirements for disconnecting means. The requirement in §

1910.147(c)(2)(iii) that energy isolating devices be capable of accepting a lockout device

whenever replacement or major repair, renovation or modification of a machine or

equipment is performed, and whenever new machines or equipment are installed after

January 2, 1990, applies in addition to any requirements in § 1910.303 through §

1910.308 that disconnecting means be capable of being locked in the open position under

certain conditions.

[46 FR 4056, Jan. 16, 1981; 46 FR 40185, Aug. 7, 1981; 72 FR 7190, Feb. 14, 2007]

035

036


General requirements. - 1910.303



• Subpart: S



• Title: General requirements.

1910.303(a)

Approval. The conductors and equipment required or permitted by this subpart shall be

acceptable only if approved, as defined in Sec. 1910.399.

1910.303(b)

Examination, installation, and use of equipment --

1910.303(b)(1)

Examination. Electric equipment shall be free from recognized hazards that are likely to

cause death or serious physical harm to employees. Safety of equipment shall be determined

using the following considerations:

1910.303(b)(1)(i)

Suitability for installation and use in conformity with the provisions of this subpart;

Note to paragraph (b)(1)(i) of this section: Suitability of equipment for an identified

purpose may be evidenced by listing or labeling for that identified purpose.

1910.303(b)(1)(ii)

Mechanical strength and durability, including, for parts designed to enclose and protect other

037

equipment, the adequacy of the protection thus provided;

1910.303(b)(1)(iii)

Wire-bending and connection space;

1910.303(b)(1)(iv)

Electrical insulation;

1910.303(b)(1)(v)

Heating effects under all conditions of use;

1910.303(b)(1)(vi)

Arcing effects;

1910.303(b)(1)(vii)

Classification by type, size, voltage, current capacity, and specific use; and

1910.303(b)(1)(viii)

Other factors that contribute to the practical safeguarding of persons using or likely to come

in contact with the equipment.

1910.303(b)(2)

Installation and use. Listed or labeled equipment shall be installed and used in accordance

with any instructions included in the listing or labeling.

1910.303(b)(3)

Insulation integrity. Completed wiring installations shall be free from short circuits and from

grounds other than those required or permitted by this subpart.

1910.303(b)(4)

Interrupting rating. Equipment intended to interrupt current at fault levels shall have an

interrupting rating sufficient for the nominal circuit voltage and the current that is available

at the line terminals of the equipment. Equipment intended to interrupt current at other than

038

fault levels shall have an interrupting rating at nominal circuit voltage sufficient for the

current that must be interrupted.

1910.303(b)(5)

Circuit impedance and other characteristics. The overcurrent protective devices, the total

impedance, the component short-circuit current ratings, and other characteristics of the

circuit to be protected shall be selected and coordinated to permit the circuit protective

devices used to clear a fault to do so without the occurrence of extensive damage to the

electrical components of the circuit. This fault shall be assumed to be either between two or

more of the circuit conductors, or between any circuit conductor and the grounding conductor

or enclosing metal raceway.

1910.303(b)(6)

Deteriorating agents. Unless identified for use in the operating environment, no conductors

or equipment shall be located in damp or wet locations; where exposed to gases, fumes,

vapors, liquids, or other agents that have a deteriorating effect on the conductors or

equipment; or where exposed to excessive temperatures.

1910.303(b)(7)

Mechanical execution of work. Electric equipment shall be installed in a neat and workmanlike

manner.

1910.303(b)(7)(i)

Unused openings in boxes, raceways, auxiliary gutters, cabinets, equipment cases, or

housings shall be effectively closed to afford protection substantially equivalent to the wall of

the equipment.

1910.303(b)(7)(ii)

Conductors shall be racked to provide ready and safe access in underground and subsurface

enclosures that persons enter for installation and maintenance.

1910.303(b)(7)(iii)

Internal parts of electrical equipment, including busbars, wiring terminals, insulators, and

other surfaces, may not be damaged or contaminated by foreign materials such as paint,

039

plaster, cleaners, abrasives, or corrosive residues.

1910.303(b)(7)(iv)

There shall be no damaged parts that may adversely affect safe operation or mechanical

strength of the equipment, such as parts that are broken, bent, cut, or deteriorated by

corrosion, chemical action, or overheating.

1910.303(b)(8)

Mounting and cooling of equipment.

1910.303(b)(8)(i)

Electric equipment shall be firmly secured to the surface on which it is mounted.

Note to paragraph (b)(8)(i) of this section: Wooden plugs driven into holes in masonry,

concrete, plaster, or similar materials are not considered secure means of fastening electric

equipment.

1910.303(b)(8)(ii)

Electric equipment that depends on the natural circulation of air and convection principles for

cooling of exposed surfaces shall be installed so that room airflow over such surfaces is not

prevented by walls or by adjacent installed equipment. For equipment designed for floor

mounting, clearance between top surfaces and adjacent surfaces shall be provided to

dissipate rising warm air.

1910.303(b)(8)(iii)

Electric equipment provided with ventilating openings shall be installed so that walls or other

obstructions do not prevent the free circulation of air through the equipment.

1910.303(c)

Electrical connections --

1910.303(c)(1)

General. Because of different characteristics of dissimilar metals:

040

1910.303(c)(1)(i)

Devices such as pressure terminal or pressure splicing connectors and soldering lugs shall be

identified for the material of the conductor and shall be properly installed and used;

1910.303(c)(1)(ii)

Conductors of dissimilar metals may not be intermixed in a terminal or splicing connector

where physical contact occurs between dissimilar conductors (such as copper and aluminum,

copper and copper-clad aluminum, or aluminum and copper-clad aluminum) unless the

device is identified for the purpose and conditions of use; and

1910.303(c)(1)(iii)

Materials such as solder, fluxes, inhibitors, and compounds, where employed, shall be

suitable for the use and shall be of a type that will not adversely affect the conductors,

installation, or equipment.

1910.303(c)(2)

Terminals.

1910.303(c)(2)(i)

Connection of conductors to terminal parts shall ensure a good connection without damaging

the conductors and shall be made by means of pressure connectors (including set-screw

type), solder lugs, or splices to flexible leads. However, No. 10 or smaller conductors may be

connected by means of wire binding screws or studs and nuts having upturned lugs or

equivalent.

1910.303(c)(2)(ii)

Terminals for more than one conductor and terminals used to connect aluminum shall be so

identified.

1910.303(c)(3)

Splices.

041

1910.303(c)(3)(i)

Conductors shall be spliced or joined with splicing devices identified for the use or by brazing,

welding, or soldering with a fusible metal or alloy. Soldered splices shall first be spliced or

joined to be mechanically and electrically secure without solder and then soldered. All splices

and joints and the free ends of conductors shall be covered with an insulation equivalent to

that of the conductors or with an insulating device identified for the purpose.

1910.303(c)(3)(ii)

Wire connectors or splicing means installed on conductors for direct burial shall be listed for

such use.

1910.303(d)

Arcing parts. Parts of electric equipment that in ordinary operation produce arcs, sparks,

flames, or molten metal shall be enclosed or separated and isolated from all combustible

material.

1910.303(e)

Marking --

1910.303(e)(1)

Identification of manufacturer and ratings. Electric equipment may not be used unless the

following markings have been placed on the equipment:

1910.303(e)(1)(i)

The manufacturer's name, trademark, or other descriptive marking by which the organization

responsible for the product may be identified; and

1910.303(e)(1)(ii)

Other markings giving voltage, current, wattage, or other ratings as necessary.

1910.303(e)(2)

Durability. The marking shall be of sufficient durability to withstand the environment

involved.

042

1910.303(f)

Disconnecting means and circuits --

1910.303(f)(1)

Motors and appliances. Each disconnecting means required by this subpart for motors and

appliances shall be legibly marked to indicate its purpose, unless located and arranged so the

purpose is evident.

1910.303(f)(2)

Services, feeders, and branch circuits. Each service, feeder, and branch circuit, at its

disconnecting means or overcurrent device, shall be legibly marked to indicate its purpose,

unless located and arranged so the purpose is evident.

1910.303(f)(3)

Durability of markings. The markings required by paragraphs (f)(1) and (f)(2) of this section

shall be of sufficient durability to withstand the environment involved.

1910.303(f)(4)

Capable of accepting a lock. Disconnecting means required by this subpart shall be capable of

being locked in the open position.

1910.303(f)(5)

Marking for series combination ratings.

1910.303(f)(5)(i)

Where circuit breakers or fuses are applied in compliance with the series combination ratings

marked on the equipment by the manufacturer, the equipment enclosures shall be legibly

marked in the field to indicate that the equipment has been applied with a series combination

rating.

1910.303(f)(5)(ii)

The marking required by paragraph (f)(5)(i) of this section shall be readily visible and shall

043

state "Caution -- Series Combination System Rated_____Amperes. Identified Replacement

Component Required."

1910.303(g)

600 Volts, nominal, or less. This paragraph applies to electric equipment operating at 600

volts, nominal, or less to ground.

1910.303(g)(1)

Space about electric equipment. Sufficient access and working space shall be provided and

maintained about all electric equipment to permit ready and safe operation and maintenance

of such equipment.

1910.303(g)(1)(i)

Working space for equipment likely to require examination, adjustment, servicing, or

maintenance while energized shall comply with the following dimensions, except as required

or permitted elsewhere in this subpart:

1910.303(g)(1)(i)(A)

The depth of the working space in the direction of access to live parts may not be less than

indicated in Table S-1. Distances shall be measured from the live parts if they are exposed or

from the enclosure front or opening if they are enclosed;

1910.303(g)(1)(i)(B)

The width of working space in front of the electric equipment shall be the width of the

equipment or 762 mm (30 in.), whichever is greater. In all cases, the working space shall

permit at least a 90-degree opening of equipment doors or hinged panels; and

1910.303(g)(1)(i)(C)

The work space shall be clear and extend from the grade, floor, or platform to the height

required by paragraph (g)(1)(vi) of this section. However, other equipment associated with

the electrical installation and located above or below the electric equipment may extend not

more than 153 mm (6 in.) beyond the front of the electric equipment.

044

1910.303(g)(1)(ii)

Working space required by this standard may not be used for storage. When normally

enclosed live parts are exposed for inspection or servicing, the working space, if in a

passageway or general open space, shall be suitably guarded.

1910.303(g)(1)(iii)

At least one entrance of sufficient area shall be provided to give access to the working space

about electric equipment.

1910.303(g)(1)(iv)

For equipment rated 1200 amperes or more and over 1.83 m (6.0 ft) wide, containing

overcurrent devices, switching devices, or control devices, there shall be one entrance not

less than 610 mm (24 in.) wide and 1.98 m (6.5 ft) high at each end of the working space,

except that:

1910.303(g)(1)(iv)(A)

Where the location permits a continuous and unobstructed way of exit travel, one means of

exit is permitted; or

1910.303(g)(1)(iv)(B)

Where the working space required by paragraph (g)(1)(i) of this section is doubled, only one

entrance to the working space is required; however, the entrance shall be located so that the

edge of the entrance nearest the equipment is the minimum clear distance given in Table S-1

away from such equipment.

1910.303(g)(1)(v)

Illumination shall be provided for all working spaces about service equipment, switchboards,

panelboards, and motor control centers installed indoors. Additional lighting fixtures are not

required where the working space is illuminated by an adjacent light source. In electric

equipment rooms, the illumination may not be controlled by automatic means only.

1910.303(g)(1)(vi)

The minimum headroom of working spaces about service equipment, switchboards,

panelboards, or motor control centers shall be as follows:

045

1910.303(g)(1)(vi)(A)

For installations built before August 13, 2007, 1.91 m (6.25 ft); and

1910.303(g)(1)(vi)(B)

For installations built on or after August 13, 2007, 1.98 m (6.5 ft), except that where the

electrical equipment exceeds 1.98 m (6.5 ft) in height, the minimum headroom may not be

less than the height of the equipment.

Table S-1. -- Minimum Depth of Clear Working Space at

Electric Equipment, 600 V or Less

Minimum clear distance for condition2 3

Condition A Condition B Condition C

Nominal voltage to ground

m ft m ft m ft

0-150

151-600

10.9

10.9

13.0

13.0

10.9

1.0

13.0

3.5

0.9

1.2

3.0

4.0

Notes to Table S-1:

1. Minimum clear distances may be 0.7 m (2.5 ft) for installations built before April 16, 1981.

2. Conditions A, B, and C are as follows:

Condition A -- Exposed live parts on one side and no live or grounded parts on the other side of

the working space, or exposed live parts on both sides effectively guarded by suitable wood or

other insulating material. Insulated wire or insulated busbars operating at not over 300 volts are

not considered live parts.

Condition B -- Exposed live parts on one side and grounded parts on the other side.

Condition C -- Exposed live parts on both sides of the work space (not guarded as provided in

Condition A) with the operator between.

3. Working space is not required in back of assemblies such as dead-front switchboards or motor

control centers where there are no renewable or adjustable parts (such as fuses or switches) on

the back and where all connections are accessible from locations other than the back. Where rear

access is required to work on deenergized parts on the back of enclosed equipment, a minimum

working space of 762 mm (30 in.) horizontally shall be provided.

046

1910.303(g)(1)(vii)

Switchboards, panelboards, and distribution boards installed for the control of light and

power circuits, and motor control centers shall be located in dedicated spaces and protected

from damage.

1910.303(g)(1)(vii)(A)

For indoor installation, the dedicated space shall comply with the following:

1910.303(g)(1)(vii)(A)(1)

The space equal to the width and depth of the equipment and extending from the floor to a

height of 1.83 m (6.0 ft) above the equipment or to the structural ceiling, whichever is lower,

shall be dedicated to the electrical installation. Unless isolated from equipment by height or

physical enclosures or covers that will afford adequate mechanical protection from vehicular

traffic or accidental contact by unauthorized personnel or that complies with paragraph

(g)(1)(vii)(A)(2) of this section, piping, ducts, or equipment foreign to the electrical

installation may not be located in this area;

1910.303(g)(1)(vii)(A)(2)

The space equal to the width and depth of the equipment shall be kept clear of foreign

systems unless protection is provided to avoid damage from condensation, leaks, or breaks in

such foreign systems. This area shall extend from the top of the electric equipment to the

structural ceiling;

1910.303(g)(1)(vii)(A)(3)

Sprinkler protection is permitted for the dedicated space where the piping complies with this

section; and

047

1910.303(g)(1)(vii)(A)(4)

Control equipment that by its very nature or because of other requirements in this subpart

must be adjacent to or within sight of its operating machinery is permitted in the dedicated

space.

Note to paragraph (g)(1)(vii)(A) of this section: A dropped, suspended, or similar ceiling

that does not add strength to the building structure is not considered a structural ceiling.

1910.303(g)(1)(vii)(B)

Outdoor electric equipment shall be installed in suitable enclosures and shall be protected

from accidental contact by unauthorized personnel, or by vehicular traffic, or by accidental

spillage or leakage from piping systems. No architectural appurtenance or other equipment

may be located in the working space required by paragraph (g)(1)(i) of this section.

1910.303(g)(2)

Guarding of live parts.

1910.303(g)(2)(i)

Except as elsewhere required or permitted by this standard, live parts of electric equipment

operating at 50 volts or more shall be guarded against accidentalcontact by use of approved

cabinets or other forms of approved enclosures or by any of the following means:

1910.303(g)(2)(i)(A)

By location in a room, vault, or similar enclosure that is accessible only to qualified persons;

1910.303(g)(2)(i)(B)

By suitable permanent, substantial partitions or screens so arranged so that only qualified

persons will have access to the space within reach of the live parts. Any openings in such

partitions or screens shall be so sized and located that persons are not likely to come into

048

accidental contact with the live parts or to bring conducting objects into contact with them;

1910.303(g)(2)(i)(C)

By placement on a suitable balcony, gallery, or platform so elevated and otherwise located as

to prevent access by unqualified persons; or

1910.303(g)(2)(i)(D)

By elevation of 2.44 m (8.0 ft) or more above the floor or other working surface.

1910.303(g)(2)(ii)

In locations where electric equipment is likely to be exposed to physical damage, enclosures

or guards shall be so arranged and of such strength as to prevent such damage.

1910.303(g)(2)(iii)

Entrances to rooms and other guarded locations containing exposed live parts shall be

marked with conspicuous warning signs forbidding unqualified persons to enter.

1910.303(h)

Over 600 volts, nominal --

1910.303(h)(1)

General. Conductors and equipment used on circuits exceeding 600 volts, nominal, shall

comply with all applicable provisions of the paragraphs (a) through (g) of this section and

with the following provisions, which supplement or modify the preceding requirements.

However, paragraphs (h)(2), (h)(3), and (h)(4) of this section do not apply to the equipment

on the supply side of the service point.

049

1910.303(h)(2)

Enclosure for electrical installations.

1910.303(h)(2)(i)

Electrical installations in a vault, room, or closet or in an area surrounded by a wall, screen,

or fence, access to which is controlled by lock and key or other approved means, are

considered to be accessible to qualified persons only. The type of enclosure used in a given

case shall be designed and constructed according to the hazards associated with the

installation.

1910.303(h)(2)(ii)

For installations other than equipment described in paragraph (h)(2)(v) of this section, a wall,

screen, or fence shall be used to enclose an outdoor electrical installation to deter access by

persons who are not qualified. A fence may not be less than 2.13 m (7.0 ft) in height or a

combination of 1.80 m (6.0 ft) or more of fence fabric and a 305-mm (1-ft) or more extension

utilizing three or more strands of barbed wire or equivalent.

1910.303(h)(2)(iii)

The following requirements apply to indoor installations that are accessible to other than

qualified persons:

1910.303(h)(2)(iii)(A)

The installations shall be made with metal-enclosed equipment or shall be enclosed in a vault

or in an area to which access is controlled by a lock;

050

1910.303(h)(2)(iii)(B)

Metal-enclosed switchgear, unit substations, transformers, pull boxes, connection boxes, and

other similar associated equipment shall be marked with appropriate caution signs; and

1910.303(h)(2)(iii)(C)

Openings in ventilated dry-type transformers and similar openings in other equipment shall

be designed so that foreign objects inserted through these openings will be deflected from

energized parts.

1910.303(h)(2)(iv)

Outdoor electrical installations having exposed live parts shall be accessible to qualified

persons only.

1910.303(h)(2)(v)

The following requirements apply to outdoor enclosed equipment accessible to unqualified

employees:

1910.303(h)(2)(v)(A)

Ventilating or similar openings in equipment shall be so designed that foreign objects

inserted through these openings will be deflected from energized parts;

1910.303(h)(2)(v)(B)

Where exposed to physical damage from vehicular traffic, suitable guards shall be provided;

1910.303(h)(2)(v)(C)

Nonmetallic or metal-enclosed equipment located outdoors and accessible to the general

public shall be designed so that exposed nuts or bolts cannot be readily removed, permitting

access to live parts;

051

1910.303(h)(2)(v)(D)

Where nonmetallic or metal-enclosed equipment is accessible to the general public and the

bottom of the enclosure is less than 2.44 m (8.0 ft) above the floor or grade level, the

enclosure door or hinged cover shall be kept locked; and

1910.303(h)(2)(v)(E)

Except for underground box covers that weigh over 45.4 kg (100 lb), doors and covers of

enclosures used solely as pull boxes, splice boxes, or junction boxes shall be locked, bolted,

or screwed on.

1910.303(h)(3)

Work space about equipment. Sufficient space shall be provided and maintained about

electric equipment to permit ready and safe operation and maintenance of such equipment.

Where energized parts are exposed, the minimum clear work space may not be less than 1.98

m (6.5 ft) high (measured vertically from the floor or platform) or less than 914 mm (3.0 ft)

wide (measured parallel to the equipment). The depth shall be as required in paragraph

(h)(5)(i) of this section. In all cases, the work space shall be adequate to permit at least a 90-

degree opening of doors or hinged panels.

1910.303(h)(4)

Entrance and access to work space.

1910.303(h)(4)(i)

At least one entrance not less than 610 mm (24 in.) wide and 1.98 m (6.5 ft) high shall be

provided to give access to the working space about electric equipment.

052

1910.303(h)(4)(i)(A)

On switchboard and control panels exceeding 1.83 m (6.0 ft) in width, there shall be one

entrance at each end of such boards unless the location of the switchboards and control

panels permits a continuous and unobstructed way of exit travel, or unless the work space

required in paragraph (h)(5)(i) of this section is doubled.

1910.303(h)(4)(i)(B)

Where one entrance to the working space is permitted under the conditions described in

paragraph (h)(4)(i)(A) of this section, the entrance shall be located so that the edge of the

entrance nearest the switchboards and control panels is at least the minimum clear distance

given in Table S-2 away from such equipment.

1910.303(h)(4)(i)(C)

Where bare energized parts at any voltage or insulated energized parts above 600 volts,

nominal, to ground are located adjacent to such entrance, they shall be suitably guarded.

1910.303(h)(4)(ii)

Permanent ladders or stairways shall be provided to give safe access to the working space

around electric equipment installed on platforms, balconies, mezzanine floors, or in attic or

roof rooms or spaces.

1910.303(h)(5)

Working space and guarding.

1910.303(h)(5)(i)

(vi) Except as elsewhere required or permitted in this subpart, the minimum clear working

space in the direction of access to live parts of electric equipment may not be less than

053

specified in Table S-2. Distances shall be measured from the live parts, if they are exposed,

or from the enclosure front or opening, if they are enclosed.

1910.303(h)(5)(ii)

If switches, cutouts, or other equipment operating at 600 volts, nominal, or less, are installed

in a room or enclosure where there are exposed live parts or exposed wiring operating at over

600 volts, nominal, the high-voltage equipment shall be effectively separated from the space

occupied by the low-voltage equipment by a suitable partition, fence, or screen. However,

switches or other equipment operating at 600 volts, nominal, or less, and serving only

equipment within the high-voltage vault, room, or enclosure may be installed in the high-

voltage enclosure, room, or vault if accessible to qualified persons only.

1910.303(h)(5)(iii)

The following requirements apply to the entrances to all buildings, rooms, or enclosures

containing exposed live parts or exposed conductors operating at over 600 volts, nominal:

1910.303(h)(5)(iii)(A)

The entrances shall be kept locked unless they are under the observation of a qualified person

at all times; and

1910.303(h)(5)(iii)(B)

Permanent and conspicuous warning signs shall be provided, reading substantially as

follows:

"DANGER -- HIGH VOLTAGE -- KEEP OUT."

1910.303(h)(5)(iv)

Illumination shall be provided for all working spaces about electric equipment.

054

1910.303(h)(5)(iv)(A)

The lighting outlets shall be arranged so that persons changing lamps or making repairs on

the lighting system will not be endangered by live parts or other equipment.

1910.303(h)(5)(iv)(B)

The points of control shall be located so that persons are prevented from contacting any live

part or moving part of the equipment while turning on the lights.

1910.303(h)(5)(v)

Unguarded live parts above working space shall be maintained at elevations not less than

specified in Table S-3.

1910.303(h)(5)(vi)

Pipes or ducts that are foreign to the electrical installation and that require periodic

maintenance or whose malfunction would endanger the operation of the electrical system

may not be located in the vicinity of service equipment, metal-enclosed power switchgear, or

industrial control assemblies. Protection shall be provided where necessary to avoid damage

from condensation leaks and breaks in such foreign systems.

Note to paragraph (h)(5)(vi) of this section: Piping and other facilities are not considered

foreign if provided for fire protection of the electrical installation.

055

Table S-2. -- Minimum Depth of Clear Working Space at

Electric Equipment, Over 600 V

Minimum clear distance for condition2 3

Condition A Condition B Condition C

Nominal voltage to ground

m ft m ft m ft

601-2500 V

2501-9000 V

9001 V-25 kV

Over 25-75 kV1

Above 75 kV1

0.9

1.2

1.5

1.8

2.5

3.0

4.0

5.0

6.0

8.0

1.2

1.5

1.8

2.5

3.0

4.0

5.0

6.0

8.0

10.0

1.5

1.8

2.8

3.0

3.7

5.0

6.0

9.0

10.0

12.0

Notes to Table S-2:

1 Minimum depth of clear working space in front of electric equipment with a nominal voltage to

ground above 25,000 volts may be the same as that for 25,000 volts under Conditions A, B, and C

for installations built before April 16, 1981.

2 Conditions A, B, and C are as follows:

Condition A -- Exposed live parts on one side and no live or grounded parts on the other side of

the working space, or exposed live parts on both sides effectively guarded by suitable wood or

other insulating material. Insulated wire or insulated busbars operating at not over 300 volts are

not considered live parts.

Condition B -- Exposed live parts on one side and grounded parts on the other side. Concrete,

brick, and tile walls are considered as grounded surfaces.

Condition C -- Exposed live parts on both sides of the work space (not guarded as provided in

Condition A) with the operator between.

3 Working space is not required in back of equipment such as dead-front switchboards or control

assemblies that has no renewable or adjustable parts (such as fuses or switches) on the back and

where all connections are accessible from locations other than the back. Where rear access is

required to work on the deenergized parts on the back of enclosed equipment, a minimum working

space 762 mm (30 in.) horizontally shall be provided.

056

Table S-3. -- Elevation of Unguarded Live Parts Above Working Space

Elevation

Nominal voltage between

phases m ft

601-7500 V

7501 V-35 kV

Over 35 kV

12.81

2.8

2.8 + 9.5 mm/kV over 35 kV

19.01

9.0

9.0 + 0.37 in./kV over 35 kV

1The minimum elevation may be 2.6 m (8.5 ft) for installations built before August 13, 2007. The

minimum elevation may be 2.4 m (8.0 ft) for installations built before April 16, 1981, if the

nominal voltage between phases is in the range of 601-6600 volts.


057

058


Wiring design and protection. - 1910.304



• Subpart: S



• Title: Wiring design and protection.

1910.304(a)

Use and identification of grounded and grounding conductors --

1910.304(a)(1)

Identification of conductors.

1910.304(a)(1)(i)

A conductor used as a grounded conductor shall be identifiable and distinguishable from all

other conductors.

1910.304(a)(1)(ii)

A conductor used as an equipment grounding conductor shall be identifiable and

distinguishable from all other conductors.

1910.304(a)(2)

Polarity of connections. No grounded conductor may be attached to any terminal or lead so

as to reverse designated polarity.

1910.304(a)(3)

Use of grounding terminals and devices. A grounding terminal or grounding-type device on a

receptacle, cord connector, or attachment plug may not be used for purposes other than

059

grounding.

1910.304(b)

Branch circuits --

1910.304(b)(1)

Identification of multiwire branch circuits. Where more than one nominal voltage system

exists in a building containing multiwire branch circuits, each ungrounded conductor of a

multiwire branch circuit, where accessible, shall be identified by phase and system. The

means of identification shall be permanently posted at each branch-circuit panelboard.

1910.304(b)(2)

Receptacles and cord connectors.

1910.304(b)(2)(i)

Receptacles installed on 15- and 20-ampere branch circuits shall be of the grounding type

except as permitted for replacement receptacles in paragraph (b)(2)(iv) of this section.

Grounding-type receptacles shall be installed only on circuits of the voltage class and current

for which they are rated, except as provided in Table S-4 and Table S-5.

1910.304(b)(2)(ii)

Receptacles and cord connectors having grounding contacts shall have those contacts

effectively grounded except for receptacles mounted on portable and vehicle-mounted

generators in accordance with paragraph (g)(3) of this section and replacement receptacles

installed in accordance with paragraph (b)(2)(iv) of this section.

1910.304(b)(2)(iii)

The grounding contacts of receptacles and cord connectors shall be grounded by connection

to the equipment grounding conductor of the circuit supplying the receptacle or cord

connector. The branch circuit wiring method shall include or provide an equipment grounding

conductor to which the grounding contacts of the receptacle or cord connector shall be

connected.

060

1910.304(b)(2)(iv)

Replacement of receptacles shall comply with the following requirements:

1910.304(b)(2)(iv)(A)

Where a grounding means exists in the receptacle enclosure or a grounding conductor is

installed, grounding-type receptacles shall be used and shall be connected to the grounding

means or conductor;

1910.304(b)(2)(iv)(B)

Ground-fault circuit-interrupter protected receptacles shall be provided where replacements

are made at receptacle outlets that are required to be so protected elsewhere in this subpart;

and

1910.304(b)(2)(iv)(C)

Where a grounding means does not exist in the receptacle enclosure, the installation shall

comply with one of the following provisions:

1910.304(b)(2)(iv)(C)(1)

A nongrounding-type receptacle may be replaced with another nongrounding-type

receptacle; or

1910.304(b)(2)(iv)(C)(2)

A nongrounding-type receptacle may be replaced with a ground-fault circuit-interrupter-type

of receptacle that is marked "No Equipment Ground;" an equipment grounding conductor

may not be connected from the ground-fault circuit-interrupter-type receptacle to any outlet

supplied from the ground-fault circuit-interrupter receptacle; or

1910.304(b)(2)(iv)(C)(3)

A nongrounding-type receptacle may be replaced with a grounding-type receptacle where

supplied through a ground-fault circuit-interrupter; the replacement receptacle shall be

marked "GFCI Protected" and "No Equipment Ground;" an equipment grounding conductor

may not be connected to such grounding-type receptacles.

061

1910.304(b)(2)(v)

Receptacles connected to circuits having different voltages, frequencies, or types of current

(ac or dc) on the same premises shall be of such design that the attachment plugs used on

these circuits are not interchangeable.

1910.304(b)(3)

Ground-fault circuit interrupter protection for personnel.

1910.304(b)(3)(i)

All 125-volt, single-phase, 15- and 20-ampere receptacles installed in bathrooms or on

rooftops shall have ground-fault circuit-interrupter protection for personnel.

1910.304(b)(3)(ii)

The following requirements apply to temporary wiring installations that are used during

maintenance, remodeling, or repair of buildings, structures, or equipment or during similar

construction-like activities.

1910.304(b)(3)(ii)(A)

All 125-volt, single-phase, 15-, 20-, and 30-ampere receptacle outlets that are not part of

the permanent wiring of the building or structure and that are in use by personnel shall have

ground-fault circuit-interrupter protection for personnel.

Note 1 to paragraph (b)(3)(ii)(A) of this section: A cord connector on an extension cord

set is considered to be a receptacle outlet if the cord set is used for temporary electric power.

Note 2 to paragraph (b)(3)(ii)(A) of this section: Cord sets and devices incorporating

the required ground-fault circuit-interrupter that are connected to the receptacle closest to

the source of power are acceptable forms of protection.

1910.304(b)(3)(ii)(B)

Receptacles other than 125 volt, single-phase, 15-, 20-, and 30-ampere receptacles that are

not part of the permanent wiring of the building or structure and that are in use by personnel

shall have ground-fault circuit-interrupter protection for personnel.

062

1910.304(b)(3)(ii)(C)

Where the ground-fault circuit-interrupter protection required by paragraph (b)(3)(ii)(B) of

this section is not available for receptacles other than 125-volt, single-phase, 15-, 20-, and

30-ampere, the employer shall establish and implement an assured equipment grounding

conductor program covering cord sets, receptacles that are not a part of the building or

structure, and equipment connected by cord and plug that are available for use or used by

employees on those receptacles. This program shall comply with the following requirements:

1910.304(b)(3)(ii)(C)(1)

A written description of the program, including the specific procedures adopted by the

employer, shall be available at the jobsite for inspection and copying by the Assistant

Secretary of Labor and any affected employee;

1910.304(b)(3)(ii)(C)(2)

The employer shall designate one or more competent persons to implement the program;

1910.304(b)(3)(ii)(C)(3)

Each cord set, attachment cap, plug, and receptacle of cord sets, and any equipment

connected by cord and plug, except cord sets and receptacles which are fixed and not

exposed to damage, shall be visually inspected before each day's use for external defects,

such as deformed or missing pins or insulation damage, and for indications of possible

internal damage. Equipment found damaged or defective shall not be used until repaired;

1910.304(b)(3)(ii)(C)(4)

The following tests shall be performed on all cord sets and receptacles which are not a part of

the permanent wiring of the building or structure, and cord- and plug-connected equipment

required to be grounded:

1910.304(b)(3)(ii)(C)(4)(i)

All equipment grounding conductors shall be tested for continuity and shall be electrically

continuous;

063

1910.304(b)(3)(ii)(C)(4)(ii)

Each receptacle and attachment cap or plug shall be tested for correct attachment of the

equipment grounding conductor. The equipment grounding conductor shall be connected to

its proper terminal; and

1910.304(b)(3)(ii)(C)(4)(iii)

All required tests shall be performed before first use; before equipment is returned to service

following any repairs; before equipment is used after any incident which can be reasonably

suspected to have caused damage (for example, when a cord set is run over); and at

intervals not to exceed 3 months, except that cord sets and receptacles which are fixed and

not exposed to damage shall be tested at intervals not exceeding 6 months;

1910.304(b)(3)(ii)(C)(5)

The employer shall not make available or permit the use by employees of any equipment

which has not met the requirements of paragraph (b)(3)(ii)(C) of this section; and

1910.304(b)(3)(ii)(C)(6)

Tests performed as required in paragraph (b)(3)(ii)(C) of this section shall be recorded. This

test record shall identify each receptacle, cord set, and cord- and plug-connected equipment

that passed the test and shall indicate the last date it was tested or the interval for which it

was tested. This record shall be kept by means of logs, color coding, or other effective means

and shall be maintained until replaced by a more current record. The record shall be made

available on the jobsite for inspection by the Assistant Secretary and any affected employee.

1910.304(b)(4)

Outlet devices. Outlet devices shall have an ampere rating not less than the load to be

served and shall comply with the following provisions:

1910.304(b)(4)(i)

Where connected to a branch circuit having a rating in excess of 20 amperes, lampholders

shall be of the heavy-duty type. A heavy-duty lampholder shall have a rating of not less than

660 watts if of the admedium type and not less than 750 watts if of any other type; and

064

1910.304(b)(4)(ii)

Receptacle outlets shall comply with the following provisions:

1910.304(b)(4)(ii)(A)

A single receptacle installed on an individual branch circuit shall have an ampere rating of not

less than that of the branch circuit;

1910.304(b)(4)(ii)(B)

Where connected to a branch circuit supplying two or more receptacles or outlets, a

receptacle may not supply a total cord- and plug-connected load in excess of the maximum

specified in Table S-4; and

1910.304(b)(4)(ii)(C)

Where connected to a branch circuit supplying two or more receptacles or outlets, receptacle

ratings shall conform to the values listed in Table S-5; or, where larger than 50 amperes, the

receptacle rating may not be less than the branch-circuit rating. However, receptacles of

cord- and plug-connected arc welders may have ampere ratings not less than the minimum

branch-circuit conductor ampacity.

1910.304(b)(5)

Cord connections. A receptacle outlet shall be installed wherever flexible cords with

attachment plugs are used. Where flexible cords are permitted to be permanently connected,

receptacles may be omitted.

065

Table S-4. -- Maximum Cord- and Plug-Connected Load to Receptacle

Circuit rating (amperes) Receptacle rating

(amperes)

Maximum load

(amperes)

15 or 20

20

30

15

20

30

12

16

24

Table S-5. -- Receptacle Ratings for Various Size Circuits

Circuit rating (amperes) Receptacle rating (amperes)

15

20

30

40

50

Not over 15

15 or 20

30

40 or 50

50

1910.304(c)

Outside conductors, 600 volts, nominal, or less. The following requirements apply to branch-

circuit, feeder, and service conductors rated 600 volts, nominal, or less and run outdoors as

open conductors.

1910.304(c)(1)

Conductors on poles. Conductors on poles shall have a separation of not less than 305 mm

(1.0 ft) where not placed on racks or brackets. Conductors supported on poles shall provide a

horizontal climbing space not less than the following:

1910.304(c)(1)(i)

Power conductors below communication conductors -- 762 mm (30 in.);

066

1910.304(c)(1)(ii)

Power conductors alone or above communication conductors:

1910.304(c)(1)(ii)(A)

300 volts or less -- 610 mm (24 in.),

1910.304(c)(1)(ii)(B)

Over 300 volts -- 762 mm (30 in.);

1910.304(c)(1)(iii)

Communication conductors below power conductors -- same as power conductors; and

1910.304(c)(1)(iv)

Communications conductors alone -- no requirement.

1910.304(c)(2)

Clearance from ground. Open conductors, open multiconductor cables, and service-drop

conductors of not over 600 volts, nominal, shall conform to the minimum clearances

specified in Table S-6.

067

Table S-6. -- Clearances From Ground

Installations built before August

13, 2007

Installations built on or after

August 13, 2007

Distance

Maximum

voltage

Conditions Voltage to

ground

Conditions

3.05 m (10.0 ft)

3.66 m (12.0 ft)

< 600 V

< 600 V

Above finished

grade or sidewalks,

or from any platform

or projection from

which they might be

reached. (If these

areas are accessible

to other than

pedestrian traffic,

then one of the

other conditions

applies).

Over areas, other

than public streets,

alleys, roads, and

driveways, subject

to vehicular traffic

other than truck

traffic.

Over areas, other

< 150 V

< 300 V

Above finished

grade or sidewalks,

or from any platform

or projection from

which they might be

reached. (If these

areas are accessible

to other than

pedestrian traffic,

then one of the

other conditions

applies.)

Over residential

property and

driveways. Over

commercial areas

subject to

pedestrian traffic or


other than truck

traffic. (This

category includes

conditions covered

under the 3.05-m

(10.0-ft) category

where the voltage

exceeds 150 V.)

Over residential

068

4.57 m (15.0 ft)

5.49 m (18.0 ft)

< 600 V

< 600 V

than public streets,

alleys, roads, and

driveways, subject

to truck traffic.

Over public streets,

alleys, roads, and

driveways.

301 to 600

V

< 600 V

property and

driveways. Over

commercial areas

subject to

pedestrian traffic or


other than truck

traffic. (This

category includes

conditions covered

under the 3.05-m

(10.0-ft) category

where the voltage

exceeds 300 V.)

Over public streets,

alleys, roads, and

driveways. Over

commercial areas

subject to truck

traffic. Other land

traversed by

vehicles, including

land used for

cultivating or

grazing and forests

and orchards.

1910.304(c)(3)

Clearance from building openings.

1910.304(c)(3)(i)

Service conductors installed as open conductors or multiconductor cable without an overall

outer jacket shall have a clearance of not less than 914 mm (3.0 ft) from windows that are

designed to be opened, doors, porches, balconies, ladders, stairs, fire escapes, and similar

locations. However, conductors that run above the top level of a window may be less than

069

914 mm (3.0 ft) from the window. Vertical clearance of final spans above, or within 914 mm

(3.0 ft) measured horizontally of, platforms, projections, or surfaces from which they might

be reached shall be maintained in accordance with paragraph (c)(2) of this section.

1910.304(c)(3)(ii)

Overhead service conductors may not be installed beneath openings through which materials

may be moved, such as openings in farm and commercial buildings, and may not be installed

where they will obstruct entrance to these building openings.

1910.304(c)(4)

Above roofs. Overhead spans of open conductors and open multiconductor cables shall have

a vertical clearance of not less than 2.44 m (8.0 ft) above the roof surface. The vertical

clearance above the roof level shall be maintained for a distance not less than 914 mm (3.0

ft) in all directions from the edge of the roof.

1910.304(c)(4)(i)

The area above a roof surface subject to pedestrian or vehicular traffic shall have a vertical

clearance from the roof surface in accordance with the clearance requirements of paragraph

(c)(2) of this section.

1910.304(c)(4)(ii)

A reduction in clearance to 914 mm (3.0 ft) is permitted where the voltage between

conductors does not exceed 300 and the roof has a slope of 102 mm (4 in.) in 305 mm (12

in.) or greater.

1910.304(c)(4)(iii)

A reduction in clearance above only the overhanging portion of the roof to not less than 457

mm (18 in.) is permitted where the voltage between conductors does not exceed 300 if:

1910.304(c)(4)(iii)(A)

The conductors do not pass above the roof overhang for a distance of more than 1.83 m (6.0

ft), 1.22 m (4.0 ft) horizontally, and

070

1910.304(c)(4)(iii)(B)

The conductors are terminated at a through-the-roof raceway or approved support.

1910.304(c)(4)(iv)

The requirement for maintaining a vertical clearance of 914 mm (3.0 ft) from the edge of the

roof does not apply to the final conductor span, where the conductors are attached to the

side of a building.

1910.304(d)

Location of outdoor lamps. Lamps for outdoor lighting shall be located below all energized

conductors, transformers, or other electric equipment, unless such equipment is controlled by

a disconnecting means that can be locked in the open position, or unless adequate clearances

or other safeguards are provided for relamping operations.

1910.304(e)

Services --

1910.304(e)(1)

Disconnecting means.

1910.304(e)(1)(i)

Means shall be provided to disconnect all conductors in a building or other structure from the

service-entrance conductors. The service disconnecting means shall plainly indicate whether

it is in the open or closed position and shall be installed at a readily accessible location

nearest the point of entrance of the service-entrance conductors.

1910.304(e)(1)(ii)

Each service disconnecting means shall simultaneously disconnect all ungrounded

conductors.

1910.304(e)(1)(iii)

Each service disconnecting means shall be suitable for the prevailing conditions.

071

1910.304(e)(2)

Services over 600 volts, nominal. The following additional requirements apply to services

over 600 volts, nominal.

1910.304(e)(2)(i)

Service-entrance conductors installed as open wires shall be guarded to make them

accessible only to qualified persons.

1910.304(e)(2)(ii)

Signs warning of high voltage shall be posted where unqualified employees might come in

contact with live parts.

1910.304(f)

Overcurrent protection --

1910.304(f)(1)

600 volts, nominal, or less. The following requirements apply to overcurrent protection of

circuits rated 600 volts, nominal, or less.

1910.304(f)(1)(i)

Conductors and equipment shall be protected from overcurrent in accordance with their

ability to safely conduct current.

1910.304(f)(1)(ii)

Except for motor running overload protection, overcurrent devices may not interrupt the

continuity of the grounded conductor unless all conductors of the circuit are opened

simultaneously.

1910.304(f)(1)(iii)

A disconnecting means shall be provided on the supply side of all fuses in circuits over 150

volts to ground and cartridge fuses in circuits of any voltage where accessible to other than

qualified persons so that each individual circuit containing fuses can be independently

disconnected from the source of power. However, a current-limiting device without a

072

disconnecting means is permitted on the supply side of the service disconnecting means. In

addition, a single disconnecting means is permitted on the supply side of more than one set

of fuses as permitted by the exception in § 1910.305(j)(4)(vi) for group operation of motors,

and a single disconnecting means is permitted for fixed electric space-heating equipment.

1910.304(f)(1)(iv)

Overcurrent devices shall be readily accessible to each employee or authorized building

management personnel. These overcurrent devices may not be located where they will be

exposed to physical damage or in the vicinity of easily ignitable material.

1910.304(f)(1)(v)

Fuses and circuit breakers shall be so located or shielded that employees will not be burned

or otherwise injured by their operation. Handles or levers of circuit breakers, and similar

parts that may move suddenly in such a way that persons in the vicinity are likely to be

injured by being struck by them, shall be guarded or isolated.

1910.304(f)(1)(vi)

Circuit breakers shall clearly indicate whether they are in the open (off) or closed (on)

position.

1910.304(f)(1)(vii)

Where circuit breaker handles on switchboards are operated vertically rather than

horizontally or rotationally, the up position of the handle shall be the closed (on) position.

1910.304(f)(1)(viii)

Circuit breakers used as switches in 120-volt and 277-volt, fluorescent lighting circuits shall

be listed and marked "SWD."

1910.304(f)(1)(ix)

A circuit breaker with a straight voltage rating, such as 240 V or 480 V, may only be installed

in a circuit in which the nominal voltage between any two conductors does not exceed the

circuit breaker's voltage rating. A two-pole circuit breaker may not be used for protecting a

3-phase, corner-grounded delta circuit unless the circuit breaker is marked 1Φ -- 3Φ to

indicate such suitability. A circuit breaker with a slash rating, such as 120/240 V or 480Y/277

073

V, may only be installed in a circuit where the nominal voltage of any conductor to ground

does not exceed the lower of the two values of the circuit breaker's voltage rating and the

nominal voltage between any two conductors does not exceed the higher value of the circuit

breaker's voltage rating.

1910.304(f)(2)

Feeders and branch circuits over 600 volts, nominal. The following requirements apply to

feeders and branch circuits energized at more than 600 volts, nominal:

1910.304(f)(2)(i)

Feeder and branch-circuit conductors shall have overcurrent protection in each ungrounded

conductor located at the point where the conductor receives its supply or at a location in the

circuit determined under engineering supervision;

1910.304(f)(2)(i)(A)

Circuit breakers used for overcurrent protection of three-phase circuits shall have a minimum

of three overcurrent relays operated from three current transformers. On three-phase, three-

wire circuits, an overcurrent relay in the residual circuit of the current transformers may

replace one of the phase relays. An overcurrent relay, operated from a current transformer

that links all phases of a three-phase, three-wire circuit, may replace the residual relay and

one other phase-conductor current transformer. Where the neutral is not grounded on the

load side of the circuit, the current transformer may link all three phase conductors and the

grounded circuit conductor (neutral); and

1910.304(f)(2)(i)(B)

If fuses are used for overcurrent protection, a fuse shall be connected in series with each

ungrounded conductor;

1910.304(f)(2)(ii)

Each protective device shall be capable of detecting and interrupting all values of current that

can occur at its location in excess of its trip setting or melting point;

1910.304(f)(2)(iii)

The operating time of the protective device, the available short-circuit current, and the

074

conductor used shall be coordinated to prevent damaging or dangerous temperatures in

conductors or conductor insulation under short-circuit conditions; and

1910.304(f)(2)(iv)

The following additional requirements apply to feeders only:

1910.304(f)(2)(iv)(A)

The continuous ampere rating of a fuse may not exceed three times the ampacity of the

conductors. The long-time trip element setting of a breaker or the minimum trip setting of an

electronically actuated fuse may not exceed six times the ampacity of the conductor. for fire

pumps, conductors may be protected for short circuit only; and

1910.304(f)(2)(iv)(B)

Conductors tapped to a feeder may be protected by the feeder overcurrent device where that

overcurrent device also protects the tap conductor.

1910.304(g)

Grounding. Paragraphs (g)(1) through (g)(9) of this section contain grounding requirements

for systems, circuits, and equipment.

1910.304(g)(1)

Systems to be grounded. Systems that supply premises wiring shall be grounded as follows:

1910.304(g)(1)(i)

All 3-wire dc systems shall have their neutral conductor grounded;

1910.304(g)(1)(ii)

Two-wire dc systems operating at over 50 volts through 300 volts between conductors shall

be grounded unless:

1910.304(g)(1)(ii)(A)

They supply only industrial equipment in limited areas and are equipped with a ground

detector;

075

1910.304(g)(1)(ii)(B)

They are rectifier-derived from an ac system complying with paragraphs (g)(1)(iii),

(g)(1)(iv), and (g)(1)(v) of this section; or

1910.304(g)(1)(ii)(C)

They are fire-alarm circuits having a maximum current of 0.030 amperes;

1910.304(g)(1)(iii)

AC circuits of less than 50 volts shall be grounded if they are installed as overhead

conductors outside of buildings or if they are supplied by transformers and the transformer

primary supply system is ungrounded or exceeds 150 volts to ground;

1910.304(g)(1)(iv)

AC systems of 50 volts to 1000 volts shall be grounded under any of the following conditions,

unless exempted by paragraph (g)(1)(v) of this section:

1910.304(g)(1)(iv)(A)

If the system can be so grounded that the maximum voltage to ground on the ungrounded

conductors does not exceed 150 volts;

1910.304(g)(1)(iv)(B)

If the system is nominally rated three-phase, four-wire wye connected in which the neutral is

used as a circuit conductor;

1910.304(g)(1)(iv)(C)

If the system is nominally rated three-phase, four-wire delta connected in which the midpoint

of one phase is used as a circuit conductor; or

1910.304(g)(1)(iv)(D)

If a service conductor is uninsulated;

1910.304(g)(1)(v)

AC systems of 50 volts to 1000 volts are not required to be grounded under any of the

076

following conditions:

1910.304(g)(1)(v)(A)

If the system is used exclusively to supply industrial electric furnaces for melting, refining,

tempering, and the like;

1910.304(g)(1)(v)(B)

If the system is separately derived and is used exclusively for rectifiers supplying only

adjustable speed industrial drives;

1910.304(g)(1)(v)(C)

If the system is separately derived and is supplied by a transformer that has a primary

voltage rating less than 1000 volts, provided all of the following conditions are met:

1910.304(g)(1)(v)(C)(1)

The system is used exclusively for control circuits;

1910.304(g)(1)(v)(C)(2)

The conditions of maintenance and supervision ensure that only qualified persons will service

the installation;

1910.304(g)(1)(v)(C)(3)

Continuity of control power is required; and

1910.304(g)(1)(v)(C)(4)

Ground detectors are installed on the control system;

1910.304(g)(1)(v)(D)

If the system is an isolated power system that supplies circuits in health care facilities; or

1910.304(g)(1)(v)(E)

If the system is a high-impedance grounded neutral system in which a grounding impedance,

usually a resistor, limits the ground-fault current to a low value for 3-phase ac systems of

077

480 volts to 1000 volts provided all of the following conditions are met:

1910.304(g)(1)(v)(E)(1)

The conditions of maintenance and supervision ensure that only qualified persons will service

the installation;

1910.304(g)(1)(v)(E)(2)

Continuity of power is required;

1910.304(g)(1)(v)(E)(3)

Ground detectors are installed on the system; and

1910.304(g)(1)(v)(E)(4)

Line-to-neutral loads are not served.

1910.304(g)(2)

Conductor to be grounded. The conductor to be grounded for ac premises wiring systems

required to be grounded by paragraph (g)(1) of this section shall be as follows:

1910.304(g)(2)(i)

One conductor of a single-phase, two-wire system shall be grounded;

1910.304(g)(2)(ii)

The neutral conductor of a single-phase, three-wire system shall be grounded;

1910.304(g)(2)(iii)

The common conductor of a multiphase system having one wire common to all phases shall

be grounded;

1910.304(g)(2)(iv)

One phase conductor of a multiphase system where one phase is grounded shall be

grounded; and

078

1910.304(g)(2)(v)

The neutral conductor of a multiphase system in which one phase is used as a neutral

conductor shall be grounded.

1910.304(g)(3)

Portable and vehicle-mounted generators.

1910.304(g)(3)(i)

The frame of a portable generator need not be grounded and may serve as the grounding

electrode for a system supplied by the generator under the following conditions:

1910.304(g)(3)(i)(A)

The generator supplies only equipment mounted on the generator or cord- and plug-

connected equipment through receptacles mounted on the generator, or both; and

1910.304(g)(3)(i)(B)

The noncurrent-carrying metal parts of equipment and the equipment grounding conductor

terminals of the receptacles are bonded to the generator frame.

1910.304(g)(3)(ii)

The frame of a vehicle need not be grounded and may serve as the grounding electrode for a

system supplied by a generator located on the vehicle under the following conditions:

1910.304(g)(3)(ii)(A)

The frame of the generator is bonded to the vehicle frame;

1910.304(g)(3)(ii)(B)

The generator supplies only equipment located on the vehicle and cord- and plug-connected

equipment through receptacles mounted on the vehicle;

1910.304(g)(3)(ii)(C)

The noncurrent-carrying metal parts of equipment and the equipment grounding conductor

terminals of the receptacles are bonded to the generator frame; and

079

1910.304(g)(3)(ii)(D)

The system complies with all other provisions of paragraph (g) of this section.

1910.304(g)(3)(iii)

A system conductor that is required to be grounded by the provisions of paragraph (g)(2) of

this section shall be bonded to the generator frame where the generator is a component of a

separately derived system.

1910.304(g)(4)

Grounding connections.

1910.304(g)(4)(i)

For a grounded system, a grounding electrode conductor shall be used to connect both the

equipment grounding conductor and the grounded circuit conductor to the grounding

electrode. Both the equipment grounding conductor and the grounding electrode conductor

shall be connected to the grounded circuit conductor on the supply side of the service

disconnecting means or on the supply side of the system disconnecting means or overcurrent

devices if the system is separately derived.

1910.304(g)(4)(ii)

For an ungrounded service-supplied system, the equipment grounding conductor shall be

connected to the grounding electrode conductor at the service equipment. For an ungrounded

separately derived system, the equipment grounding conductor shall be connected to the

grounding electrode conductor at, or ahead of, the system disconnecting means or

overcurrent devices.

1910.304(g)(4)(iii)

On extensions of existing branch circuits that do not have an equipment grounding

conductor, grounding-type receptacles may be grounded to a grounded cold water pipe near

the equipment if the extension was installed before August 13, 2007. When any element of

this branch circuit is replaced, the entire branch circuit shall use an equipment grounding

conductor that complies with all other provisions of paragraph (g) of this section.

080

1910.304(g)(5)

Grounding path. The path to ground from circuits, equipment, and enclosures shall be

permanent, continuous, and effective.

1910.304(g)(6)

Supports, enclosures, and equipment to be grounded.

1910.304(g)(6)(i)

Metal cable trays, metal raceways, and metal enclosures for conductors shall be grounded,

except that:

1910.304(g)(6)(i)(A)

Metal enclosures such as sleeves that are used to protect cable assemblies from physical

damage need not be grounded; and

1910.304(g)(6)(i)(B)

Metal enclosures for conductors added to existing installations of open wire, knob-and-tube

wiring, and nonmetallic-sheathed cable need not be grounded if all of the following conditions

are met:

1910.304(g)(6)(i)(B)(1)

Runs are less than 7.62 meters (25.0 ft);

1910.304(g)(6)(i)(B)(2)

Enclosures are free from probable contact with ground, grounded metal, metal laths, or other

conductive materials; and

1910.304(g)(6)(i)(B)(3)

Enclosures are guarded against employee contact.

1910.304(g)(6)(ii)

Metal enclosures for service equipment shall be grounded.

081

1910.304(g)(6)(iii)

Frames of electric ranges, wall-mounted ovens, counter-mounted cooking units, clothes

dryers, and metal outlet or junction boxes that are part of the circuit for these appliances

shall be grounded.

1910.304(g)(6)(iv)

Exposed noncurrent-carrying metal parts of fixed equipment that may become energized

shall be grounded under any of the following conditions:

1910.304(g)(6)(iv)(A)

If within 2.44 m (8 ft) vertically or 1.52 m (5 ft) horizontally of ground or grounded metal

objects and subject to employee contact;

1910.304(g)(6)(iv)(B)

If located in a wet or damp location and not isolated;

1910.304(g)(6)(iv)(C)

If in electrical contact with metal;

1910.304(g)(6)(iv)(D)

If in a hazardous (classified) location;

1910.304(g)(6)(iv)(E)

If supplied by a metal-clad, metal-sheathed, or grounded metal raceway wiring method; or

1910.304(g)(6)(iv)(F)

If equipment operates with any terminal at over 150 volts to ground.

1910.304(g)(6)(v)

Notwithstanding the provisions of paragraph (g)(6)(iv) of this section, exposed noncurrent-

carrying metal parts of the following types of fixed equipment need not be grounded:

082

1910.304(g)(6)(v)(A)

Enclosures for switches or circuit breakers used for other than service equipment and

accessible to qualified persons only;

1910.304(g)(6)(v)(B)

Electrically heated appliances that are permanently and effectively insulated from ground;

1910.304(g)(6)(v)(C)

Distribution apparatus, such as transformer and capacitor cases, mounted on wooden poles,

at a height exceeding 2.44 m (8.0 ft) above ground or grade level; and

1910.304(g)(6)(v)(D)

Listed equipment protected by a system of double insulation, or its equivalent, and

distinctively marked as such.

1910.304(g)(6)(vi)

Exposed noncurrent-carrying metal parts of cord- and plug-connected equipment that may

become energized shall be grounded under any of the following conditions:

1910.304(g)(6)(vi)(A)

If in hazardous (classified) locations (see § 1910.307);

1910.304(g)(6)(vi)(B)

If operated at over 150 volts to ground, except for guarded motors and metal frames of

electrically heated appliances if the appliance frames are permanently and effectively

insulated from ground;

1910.304(g)(6)(vi)(C)

If the equipment is of the following types:

1910.304(g)(6)(vi)(C)(1)

Refrigerators, freezers, and air conditioners;

083

1910.304(g)(6)(vi)(C)(2)

Clothes-washing, clothes-drying, and dishwashing machines, sump pumps, and electric

aquarium equipment;

1910.304(g)(6)(vi)(C)(3)

Hand-held motor-operated tools, stationary and fixed motor-operated tools, and light

industrial motor-operated tools;

1910.304(g)(6)(vi)(C)(4)

Motor-operated appliances of the following types: hedge clippers, lawn mowers, snow

blowers, and wet scrubbers;

1910.304(g)(6)(vi)(C)(5)

Cord- and plug-connected appliances used in damp or wet locations, or by employees

standing on the ground or on metal floors or working inside of metal tanks or boilers;

1910.304(g)(6)(vi)(C)(6)

Portable and mobile X-ray and associated equipment;

1910.304(g)(6)(vi)(C)(7)

Tools likely to be used in wet and conductive locations; and

1910.304(g)(6)(vi)(C)(8)

Portable hand lamps.

1910.304(g)(6)(vii)

Notwithstanding the provisions of paragraph (g)(6)(vi) of this section, the following

equipment need not be grounded:

1910.304(g)(6)(vii)(A)

Tools likely to be used in wet and conductive locations if supplied through an isolating

transformer with an ungrounded secondary of not over 50 volts; and

084

1910.304(g)(6)(vii)(B)

Listed or labeled portable tools and appliances if protected by an approved system of double

insulation, or its equivalent, and distinctively marked.

1910.304(g)(7)

Nonelectrical equipment. The metal parts of the following nonelectrical equipment shall be

grounded: frames and tracks of electrically operated cranes and hoists; frames of

nonelectrically driven elevator cars to which electric conductors are attached; hand-operated

metal shifting ropes or cables of electric elevators; and metal partitions, grill work, and

similar metal enclosures around equipment of over 750 volts between conductors.

1910.304(g)(8)

Methods of grounding fixed equipment.

1910.304(g)(8)(i)

Noncurrent-carrying metal parts of fixed equipment, if required to be grounded by this

subpart, shall be grounded by an equipment grounding conductor that is contained within the

same raceway, cable, or cord, or runs with or encloses the circuit conductors. For dc circuits

only, the equipment grounding conductor may be run separately from the circuit conductors.

1910.304(g)(8)(ii)

Electric equipment is considered to be effectively grounded if it is secured to, and in electrical

contact with, a metal rack or structure that is provided for its support and the metal rack or

structure is grounded by the method specified for the noncurrent-carrying metal parts of

fixed equipment in paragraph (g)(8)(i) of this section. Metal car frames supported by metal

hoisting cables attached to or running over metal sheaves or drums of grounded elevator

machines are also considered to be effectively grounded.

1910.304(g)(8)(iii)

For installations made before April 16, 1981, electric equipment is also considered to be

effectively grounded if it is secured to, and in metallic contact with, the grounded structural

metal frame of a building. When any element of this branch circuit is replaced, the entire

branch circuit shall use an equipment grounding conductor that complies with all other

provisions of paragraph (g) of this section.

085

1910.304(g)(9)

Grounding of systems and circuits of 1000 volts and over (high voltage). If high voltage

systems are grounded, they shall comply with all applicable provisions of paragraphs (g)(1)

through (g)(8) of this section as supplemented and modified by the following requirements:

1910.304(g)(9)(i)

Systems supplying portable or mobile high voltage equipment, other than substations

installed on a temporary basis, shall comply with the following:

1910.304(g)(9)(i)(A)

The system shall have its neutral grounded through an impedance. If a delta-connected high

voltage system is used to supply the equipment, a system neutral shall be derived.

1910.304(g)(9)(i)(B)

Exposed noncurrent-carrying metal parts of portable and mobile equipment shall be

connected by an equipment grounding conductor to the point at which the system neutral

impedance is grounded.

1910.304(g)(9)(i)(C)

Ground-fault detection and relaying shall be provided toautomatically deenergize any high

voltage system component that has developed a ground fault. The continuity of the

equipment grounding conductor shall be continuously monitored so as to deenergize

automatically the high voltage feeder to the portable equipment upon loss of continuity of the

equipment grounding conductor.

1910.304(g)(9)(i)(D)

The grounding electrode to which the portable equipment system neutral impedance is

connected shall be isolated from and separated in the ground by at least 6.1 m (20.0 ft) from

any other system or equipment grounding electrode, and there shall be no direct connection

between the grounding electrodes, such as buried pipe, fence, and so forth.

1910.304(g)(9)(ii)

All noncurrent-carrying metal parts of portable equipment and fixed equipment, including

their associated fences, housings, enclosures, and supporting structures, shall be grounded.

086

However, equipment that is guarded by location and isolated from ground need not be

grounded. Additionally, pole-mounted distribution apparatus at a height exceeding 2.44 m

(8.0 ft) above ground or grade level need not be grounded.

[46 FR 4056, Jan. 16, 1981; 46 FR 40185, Aug. 7, 1981, as amended at 55 FR 32015, Aug.

6, 1990; 72 FR 7195, Feb. 14, 2007]

087

088


Wiring methods, components, and equipment for general use. -

1910.305



• Subpart: S



• Title: Wiring methods, components, and equipment for general

use.

1910.305(a)

Wiring methods. The provisions of this section do not apply to conductors that are an

integral part of factory-assembled equipment.

1910.305(a)(1)

General requirements.

1910.305(a)(1)(i)

Metal raceways, cable trays, cable armor, cable sheath, enclosures, frames, fittings, and

other metal noncurrent-carrying parts that are to serve as grounding conductors, with or

without the use of supplementary equipment grounding conductors, shall be effectively

bonded where necessary to ensure electrical continuity and the capacity to conduct safely

any fault current likely to be imposed on them. Any nonconductive paint, enamel, or

similar coating shall be removed at threads, contact points, and contact surfaces or be

connected by means of fittings designed so as to make such removal unnecessary.

1910.305(a)(1)(ii)

Where necessary for the reduction of electrical noise (electromagnetic interference) of the

grounding circuit, an equipment enclosure supplied by a branch circuit may be isolated

from a raceway containing circuits supplying only that equipment by one or more listed

nonmetallic raceway fittings located at the point of attachment of the raceway to the

089

equipment enclosure. The metal raceway shall be supplemented by an internal insulated

equipment grounding conductor installed to ground the equipment enclosure.

1910.305(a)(1)(iii)

No wiring systems of any type may be installed in ducts used to transport dust, loose

stock, or flammable vapors. No wiring system of any type may be installed in any duct

used for vapor removal or for ventilation of commercial-type cooking equipment, or in

any shaft containing only such ducts.

1910.305(a)(2)

Temporary wiring. Except as specifically modified in this paragraph, all other

requirements of this subpart for permanent wiring shall also apply to temporary wiring

installations.

1910.305(a)(2)(i)

Temporary electrical power and lighting installations of 600 volts, nominal, or less may be

used only as follows:

1910.305(a)(2)(i)(A)

During and for remodeling, maintenance, or repair of buildings, structures, or equipment,

and similar activities;

1910.305(a)(2)(i)(B)

For a period not to exceed 90 days for Christmas decorative lighting, carnivals, and

similar purposes; or

1910.305(a)(2)(i)(C)

For experimental or development work, and during emergencies.

1910.305(a)(2)(ii)

Temporary wiring shall be removed immediately upon completion of the project or

purpose for which the wiring was installed.

090

1910.305(a)(2)(iii)

Temporary electrical installations of more than 600 volts may be used only during periods

of tests, experiments, emergencies, or construction-like activities.

1910.305(a)(2)(iv)

The following requirements apply to feeders:

1910.305(a)(2)(iv)(A)

Feeders shall originate in an approved distribution center.

1910.305(a)(2)(iv)(B)

Conductors shall be run as multiconductor cord or cable assemblies. However, if installed

as permitted in paragraph (a)(2)(i)(C) of this section, and if accessible only to qualified

persons, feeders may be run as single insulated conductors.

1910.305(a)(2)(v)

The following requirements apply to branch circuits:

1910.305(a)(2)(v)(A)

Branch circuits shall originate in an approved power outlet or panelboard.

1910.305(a)(2)(v)(B)

Conductors shall be multiconductor cord or cable assemblies or open conductors. If run

as open conductors, they shall be fastened at ceiling height every 3.05 m (10.0 ft).

1910.305(a)(2)(v)(C)

No branch-circuit conductor may be laid on the floor.

1910.305(a)(2)(v)(D)

Each branch circuit that supplies receptacles or fixed equipment shall contain a separate

equipment grounding conductor if run as open conductors.

091

1910.305(a)(2)(vi)

Receptacles shall be of the grounding type. Unless installed in a continuous grounded

metallic raceway or metallic covered cable, each branch circuit shall contain a separate

equipment grounding conductor and all receptacles shall be electrically connected to the

grounding conductor.

1910.305(a)(2)(vii)

No bare conductors nor earth returns may be used for the wiring of any temporary

circuit.

1910.305(a)(2)(viii)

Suitable disconnecting switches or plug connectors shall be installed to permit the

disconnection of all ungrounded conductors of each temporary circuit. Multiwire branch

circuits shall be provided with a means to disconnect simultaneously all ungrounded

conductors at the power outlet or panelboard where the branch circuit originated.

Note to paragraph (a)(2)(viii) of this section. Circuit breakers with their handles

connected by approved handle ties are considered a single disconnecting means for the

purpose of this requirement.

1910.305(a)(2)(ix)

All lamps for general illumination shall be protected from accidental contact or breakage

by a suitable fixture or lampholder with a guard. Brass shell, paper-lined sockets, or

other metal-cased sockets may not be used unless the shell is grounded.

1910.305(a)(2)(x)

Flexible cords and cables shall be protected from accidental damage, as might be caused,

for example, by sharp corners, projections, and doorways or other pinch points.

1910.305(a)(2)(xi)

Cable assemblies and flexible cords and cables shall be supported in place at intervals

that ensure that they will be protected from physical damage. Support shall be in the

form of staples, cables ties, straps, or similar type fittings installed so as not to cause

damage.

092

1910.305(a)(3)

Cable trays.

1910.305(a)(3)(i)

Only the following wiring methods may be installed in cable tray systems: armored cable;

electrical metallic tubing; electrical nonmetallic tubing; fire alarm cables; flexible metal

conduit; flexible metallic tubing; instrumentation tray cable; intermediate metal conduit;

liquidtight flexible metal conduit; liquidtight flexible nonmetallic conduit; metal-clad

cable; mineral-insulated, metal-sheathed cable; multiconductor service-entrance cable;

multiconductor underground feeder and branch-circuit cable; multipurpose and

communications cables; nonmetallic-sheathed cable; power and control tray cable;

power-limited tray cable; optical fiber cables; and other factory-assembled,

multiconductor control, signal, or power cables that are specifically approved for

installation in cable trays, rigid metal conduit, and rigid nonmetallic conduit.

1910.305(a)(3)(ii)

In industrial establishments where conditions of maintenance and supervision assure that

only qualified persons will service the installed cable tray system, the following cables

may also be installed in ladder, ventilated-trough, or ventilated-channel cable trays:

1910.305(a)(3)(ii)(A)

Single conductor cable; the cable shall be No. 1/0 or larger and shall be of a type listed

and marked on the surface for use in cable trays; where Nos. 1/0 through 4/0 single

conductor cables are installed in ladder cable tray, the maximum allowable rung spacing

for the ladder cable tray shall be 229 mm (9 in.); where exposed to direct rays of the

sun, cables shall be identified as being sunlight resistant;

1910.305(a)(3)(ii)(B)

Welding cables installed in dedicated cable trays;

1910.305(a)(3)(ii)(C)

Single conductors used as equipment grounding conductors; these conductors, which

may be insulated, covered, or bare, shall be No. 4 or larger; and

093

1910.305(a)(3)(ii)(D)

Multiconductor cable, Type MV; where exposed to direct rays of the sun, the cable shall

be identified as being sunlight resistant.

1910.305(a)(3)(iii)

Metallic cable trays may be used as equipment grounding conductors only where

continuous maintenance and supervision ensure that qualified persons will service the

installed cable tray system.

1910.305(a)(3)(iv)

Cable trays in hazardous (classified) locations may contain only the cable types permitted

in such locations. (See § 1910.307.)

1910.305(a)(3)(v)

Cable tray systems may not be used in hoistways or where subjected to severe physical

damage.

1910.305(a)(4)

Open wiring on insulators>.

1910.305(a)(4)(i)

Open wiring on insulators is only permitted on systems of 600 volts, nominal, or less for

industrial or agricultural establishments, indoors or outdoors, in wet or dry locations,

where subject to corrosive vapors, and for services.

1910.305(a)(4)(ii)

Conductors smaller than No. 8 shall be rigidly supported on noncombustible,

nonabsorbent insulating materials and may not contact any other objects. Supports shall

be installed as follows:

1910.305(a)(4)(ii)(A)

Within 152 mm (6 in.) from a tap or splice;

094

1910.305(a)(4)(ii)(B)

Within 305 mm (12 in.) of a dead-end connection to a lampholder or receptacle; and

1910.305(a)(4)(ii)(C)

At intervals not exceeding 1.37 m (4.5 ft), and at closer intervals sufficient to provide

adequate support where likely to be disturbed.

1910.305(a)(4)(iii)

In dry locations, where not exposed to severe physical damage, conductors may be

separately enclosed in flexible nonmetallic tubing. The tubing shall be in continuous

lengths not exceeding 4.57 m (15.0 ft) and secured to the surface by straps at intervals

not exceeding 1.37 m (4.5 ft).

1910.305(a)(4)(iv)

Open conductors shall be separated from contact with walls, floors, wood cross members,

or partitions through which they pass by tubes or bushings of noncombustible,

nonabsorbent insulating material. if the bushing is shorter than the hole, a waterproof

sleeve of nonconductive material shall be inserted in the hole and an insulating bushing

slipped into the sleeve at each end in such a manner as to keep the conductors

absolutely out of contact with the sleeve. Each conductor shall be carried through a

separate tube or sleeve.

1910.305(a)(4)(v)

Where open conductors cross ceiling joints and wall studs and are exposed to physical

damage (for example, located within 2.13 m (7.0 ft) of the floor), they shall be protected.

1910.305(b)

Cabinets, boxes, and fittings --

1910.305(b)(1)

Conductors entering boxes, cabinets, or fittings.

095

1910.305(b)(1)(i)

Conductors entering cutout boxes, cabinets, or fittings shall be protected from abrasion,

and openings through which conductors enter shall be effectively closed.

1910.305(b)(1)(ii)

Unused openings in cabinets, boxes, and fittings shall be effectively closed.

1910.305(b)(1)(iii)

Where cable is used, each cable shall be secured to the cabinet, cutout box, or meter

socket enclosure. However, where cable with an entirely nonmetallic sheath enters the

top of a surface-mounted enclosure through one or more nonflexible raceways not less

than 457 mm (18 in.) or more than 3.05 m (10.0 ft) in length, the cable need not be

secured to the cabinet, box, or enclosure provided all of the following conditions are met:

1910.305(b)(1)(iii)(A)

Each cable is fastened within 305 mm (12 in.) of the outer end of the raceway, measured

along the sheath;

1910.305(b)(1)(iii)(B)

The raceway extends directly above the enclosure and does not penetrate a structural

ceiling;

1910.305(b)(1)(iii)(C)

A fitting is provided on each end of the raceway to protect the cable from abrasion, and

the fittings remain accessible after installation;

1910.305(b)(1)(iii)(D)

The raceway is sealed or plugged at the outer end using approved means so as to

prevent access to the enclosure through the raceway;

1910.305(b)(1)(iii)(E)

The cable sheath is continuous through the raceway and extends into the enclosure not

less than 6.35 mm (0.25 in.) beyond the fitting;

096

1910.305(b)(1)(iii)(F)

The raceway is fastened at its outer end and at other points as necessary; and

1910.305(b)(1)(iii)(G)

Where installed as conduit or tubing, the allowable cable fill does not exceed that

permitted for complete conduit or tubing systems.

1910.305(b)(2)

Covers and canopies.

1910.305(b)(2)(i)

All pull boxes, junction boxes, and fittings shall be provided with covers identified for the

purpose. If metal covers are used, they shall be grounded. In completed installations,

each outlet box shall have a cover, faceplate, or fixture canopy. Covers of outlet boxes

having holes through which flexible cord pendants pass shall be provided with bushings

designed for the purpose or shall have smooth, well-rounded surfaces on which the cords

may bear.

1910.305(b)(2)(ii)

Where a fixture canopy or pan is used, any combustible wall or ceiling finish exposed

between the edge of the canopy or pan and the outlet box shall be covered with

noncombustible material.

1910.305(b)(3)

Pull and junction boxes for systems over 600 volts, nominal. In addition to other

requirements in this section, the following requirements apply to pull and junction boxes

for systems over 600 volts, nominal:

1910.305(b)(3)(i)

Boxes shall provide a complete enclosure for the contained conductors or cables.

097

1910.305(b)(3)(ii)

Boxes shall be closed by suitable covers securely fastened in place.

Note to paragraph (b)(3)(ii) of this section: Underground box covers that weigh

over 45.4 kg (100 lbs) meet this requirement.

1910.305(b)(3)(iii)

Covers for boxes shall be permanently marked "HIGH VOLTAGE." The marking shall be on

the outside of the box cover and shall be readily visible and legible.

1910.305(c)

Switches --

1910.305(c)(1)

Single-throw knife switches. Single-throw knife switches shall be so placed that gravity

will not tend to close them. Single-throw knife switches approved for use in the inverted

position shall be provided with a locking device that will ensure that the blades remain in

the open position when so set.

1910.305(c)(2)

Double-throw knife switches. Double-throw knife switches may be mounted so that the

throw will be either vertical or horizontal. However, if the throw is vertical, a locking

device shall be provided to ensure that the blades remain in the open position when so

set.

1910.305(c)(3)

Connection of switches.

1910.305(c)(3)(i)

Single-throw knife switches and switches with butt contacts shall be connected so that

the blades are deenergized when the switch is in the open position.

098

1910.305(c)(3)(ii)

Single-throw knife switches, molded-case switches, switches with butt contacts, and

circuit breakers used as switches shall be connected so that the terminals supplying the

load are deenergized when the switch is in the open position. However, blades and

terminals supplying the load of a switch may be energized when the switch is in the open

position where the switch is connected to circuits or equipment inherently capable of

providing a backfeed source of power. For such installations, a permanent sign shall be

installed on the switch enclosure or immediately adjacent to open switches that read,

"WARNING -- LOAD SIDE TERMINALS MAY BE ENERGIZED BY BACKFEED."

1910.305(c)(4)

Faceplates for flush-mounted snap switches. Snap switches mounted in boxes shall have

faceplates installed so as to completely cover the opening and seat against the finished

surface.

1910.305(c)(5)

Grounding. Snap switches, including dimmer switches, shall be effectively grounded and

shall provide a means to ground metal faceplates, whether or not a metal faceplate is

installed. However, if no grounding means exists within the snap-switch enclosure, or

where the wiring method does not include or provide an equipment ground, a snap switch

without a grounding connection is permitted for replacement purposes only. Such snap

switches shall be provided with a faceplate of nonconducting, noncombustible material if

they are located within reach of conducting floors or other conducting surfaces.

1910.305(d)

Switchboards and panelboards --

1910.305(d)(1)

Switchboards with exposed live parts. Switchboards that have any exposed live parts

shall be located in permanently dry locations and shall be accessible only to qualified

persons.

099

1910.305(d)(2)

Panelboard enclosures. Panelboards shall be mounted in cabinets, cutout boxes, or

enclosures designed for the purpose and shall be dead front. However, panelboards other

than the dead front externally-operable type are permitted where accessible only to

qualified persons.

1910.305(d)(3)

Knife switches mounted in switchboards or panelboards. Exposed blades of knife switches

mounted in switchboards or panelboards shall be dead when open.

1910.305(e)

Enclosures for damp or wet locations --

1910.305(e)(1)

Cabinets, cutout boxes, fittings, boxes, and panelboard enclosures. Cabinets, cutout

boxes, fittings, boxes, and panelboard enclosures in damp or wet locations shall be

installed so as to prevent moisture or water from entering and accumulating within the

enclosures and shall be mounted so there is at least 6.35-mm (0.25-in.) airspace

between the enclosure and the wall or other supporting surface. However, nonmetallic

enclosures may be installed without the airspace on a concrete, masonry, tile, or similar

surface. The enclosures shall be weatherproof in wet locations.

1910.305(e)(2)

Switches, circuit breakers, and switchboards. Switches, circuit breakers, and

switchboards installed in wet locations shall be enclosed in weatherproof enclosures.

1910.305(f)

Conductors for general wiring --

1910.305(f)(1)

Insulation. All conductors used for general wiring shall be insulated unless otherwise

permitted in this subpart.

100

1910.305(f)(2)

Type. The conductor insulation shall be of a type that is approved for the voltage,

operating temperature, and location of use.

1910.305(f)(3)

Distinguishable. Insulated conductors shall be distinguishable by appropriate color or

other suitable means as being grounded conductors, ungrounded conductors, or

equipment grounding conductors.

1910.305(g)

Flexible cords and cables --

1910.305(g)(1)

Use of flexible cords and cables.

1910.305(g)(1)(i)

Flexible cords and cables shall be approved for conditions of use and location.

1910.305(g)(1)(ii)

Flexible cords and cables may be used only for:

1910.305(g)(1)(ii)(A)

Pendants;

1910.305(g)(1)(ii)(B)

Wiring of fixtures;

1910.305(g)(1)(ii)(C)

Connection of portable lamps or appliances;

101

1910.305(g)(1)(ii)(D)

Portable and mobile signs;

1910.305(g)(1)(ii)(E)

Elevator cables;

1910.305(g)(1)(ii)(F)

Wiring of cranes and hoists;

1910.305(g)(1)(ii)(G)

Connection of stationary equipment to facilitate their frequent interchange;

1910.305(g)(1)(ii)(H)

Prevention of the transmission of noise or vibration;

1910.305(g)(1)(ii)(I)

Appliances where the fastening means and mechanical connections are designed to

permit removal for maintenance and repair;

1910.305(g)(1)(ii)(J)

Data processing cables approved as a part of the data processing system;

1910.305(g)(1)(ii)(K)

Connection of moving parts; and

1910.305(g)(1)(ii)(L)

Temporary wiring as permitted in paragraph (a)(2) of this section.

1910.305(g)(1)(iii)

If used as permitted in paragraphs (g)(1)(ii)(C), (g)(1)(ii)(G), or (g)(1)(ii)(I) of this

section, the flexible cord shall be equipped with an attachment plug and shall be

energized from an approved receptacle outlet.

102

1910.305(g)(1)(iv)

Unless specifically permitted otherwise in paragraph (g)(1)(ii) of this section, flexible

cords and cables may not be used:

1910.305(g)(1)(iv)(A)

As a substitute for the fixed wiring of a structure;

1910.305(g)(1)(iv)(B)

Where run through holes in walls, ceilings, or floors;

1910.305(g)(1)(iv)(C)

Where run through doorways, windows, or similar openings;

1910.305(g)(1)(iv)(D)

Where attached to building surfaces;

1910.305(g)(1)(iv)(E)

Where concealed behind building walls, ceilings, or floors; or

1910.305(g)(1)(iv)(F)

Where installed in raceways, except as otherwise permitted in this subpart.

1910.305(g)(1)(v)

Flexible cords used in show windows and showcases shall be Type S, SE, SEO, SEOO, SJ,

SJE, SJEO, SJEOO, SJO, SJOO, SJT, SJTO, SJTOO, SO, SOO, ST, STO, or STOO, except

for the wiring of chain-supported lighting fixtures and supply cords for portable lamps and

other merchandise being displayed or exhibited.

1910.305(g)(2)

Identification, splices, and terminations.

103

1910.305(g)(2)(i)

A conductor of a flexible cord or cable that is used as a grounded conductor or an

equipment grounding conductor shall be distinguishable from other conductors. Types S,

SC, SCE, SCT, SE, SEO, SEOO, SJ, SJE, SJEO, SJEOO, SJO, SJT, SJTO, SJTOO, SO, SOO,

ST, STO, and STOO flexible cords and Types G, G-GC, PPE, and W flexible cables shall be

durably marked on the surface at intervals not exceeding 610 mm (24 in.) with the type

designation, size, and number of conductors.

1910.305(g)(2)(ii)

Flexible cords may be used only in continuous lengths without splice or tap. Hard-service

cord and junior hard-service cord No. 14 and larger may be repaired if spliced so that the

splice retains the insulation, outer sheath properties, and usage characteristics of the

cord being spliced.

1910.305(g)(2)(iii)

Flexible cords and cables shall be connected to devices and fittings so that strain relief is

provided that will prevent pull from being directly transmitted to joints or terminal

screws.

1910.305(h)

Portable cables over 600 volts, nominal. This paragraph applies to portable cables used at

more than 600 volts, nominal.

1910.305(h)(1)

Conductor construction. Multiconductor portable cable for use in supplying power to

portable or mobile equipment at over 600 volts, nominal, shall consist of No. 8 or larger

conductors employing flexible stranding. However, the minimum size of the insulated

ground-check conductor of Type G-GC cables shall be No. 10.

1910.305(h)(2)

Shielding. Cables operated at over 2,000 volts shall be shielded for the purpose of

confining the voltage stresses to the insulation.

104

1910.305(h)(3)

Equipment grounding conductors. Grounding conductors shall be provided.

1910.305(h)(4)

Grounding shields. All shields shall be grounded.

1910.305(h)(5)

Minimum bending radii. The minimum bending radii for portable cables during installation

and handling in service shall be adequate to prevent damage to the cable.

1910.305(h)(6)

Fittings. Connectors used to connect lengths of cable in a run shall be of a type that lock

firmly together. Provisions shall be made to prevent opening or closing these connectors

while energized. Strain relief shall be provided at connections and terminations.

1910.305(h)(7)

Splices. Portable cables may not be operated with splices unless the splices are of the

permanent molded, vulcanized, or other approved type.

1910.305(h)(8)

Terminations. Termination enclosures shall be suitably marked with a high voltage hazard

warning, and terminations shall be accessible only to authorized and qualified employees.

1910.305(i)

Fixture wires --

1910.305(i)(1)

General. Fixture wires shall be approved for the voltage, temperature, and location of

use. A fixture wire which is used as a grounded conductor shall be identified.

1910.305(i)(2)

Uses permitted. Fixture wires may be used only:

105

1910.305(i)(2)(i)

For installation in lighting fixtures and in similar equipment where enclosed or protected

and not subject to bending or twisting in use; or

1910.305(i)(2)(ii)

For connecting lighting fixtures to the branch-circuit conductors supplying the fixtures.

1910.305(i)(3)

Uses not permitted. Fixture wires may not be used as branch-circuit conductors except as

permitted for Class 1 power limited circuits and for fire alarm circuits.

1910.305(j)

Equipment for general use --

1910.305(j)(1)

Lighting fixtures, lampholders, lamps, and receptacles.

1910.305(j)(1)(i)

Fixtures, lampholders, lamps, rosettes, and receptacles may have no live parts normally

exposed to employee contact. However, rosettes and cleat-type lampholders and

receptacles located at least 2.44 m (8.0 ft) above the floor may have exposed terminals.

1910.305(j)(1)(ii)

Handlamps of the portable type supplied through flexible cords shall be equipped with a

handle of molded composition or other material identified for the purpose, and a

substantial guard shall be attached to the lampholder or the handle. Metal shell, paper-

lined lampholders may not be used.

1910.305(j)(1)(iii)

Lampholders of the screw-shell type shall be installed for use as lampholders only. Where

supplied by a circuit having a grounded conductor, the grounded conductor shall be

connected to the screw shell. Lampholders installed in wet or damp locations shall be of

the weatherproof type.

106

1910.305(j)(1)(iv)

Fixtures installed in wet or damp locations shall be identified for the purpose and shall be

so constructed or installed that water cannot enter or accumulate in wireways,

lampholders, or other electrical parts.

1910.305(j)(2)

Receptacles, cord connectors, and attachment plugs (caps).

1910.305(j)(2)(i)

All 15- and 20-ampere attachment plugs and connectors shall be constructed so that

there are no exposed current-carrying parts except the prongs, blades, or pins. The cover

for wire terminations shall be a part that is essential for the operation of an attachment

plug or connector (dead-front construction). Attachment plugs shall be installed so that

their prongs, blades, or pins are not energized unless inserted into an energized

receptacle. No receptacles may be installed so as to require an energized attachment

plug as its source of supply.

1910.305(j)(2)(ii)

Receptacles, cord connectors, and attachment plugs shall be constructed so that no

receptacle or cord connector will accept an attachment plug with a different voltage or

current rating than that for which the device is intended. However, a 20-ampere T-slot

receptacle or cord connector may accept a 15-ampere attachment plug of the same

voltage rating.

1910.305(j)(2)(iii)

Nongrounding-type receptacles and connectors may not be used for grounding-type

attachment plugs.

1910.305(j)(2)(iv)

A receptacle installed in a wet or damp location shall be suitable for the location.

1910.305(j)(2)(v)

A receptacle installed outdoors in a location protected from the weather or in other damp

locations shall have an enclosure for the receptacle that is weatherproof when the

107

receptacle is covered (attachment plug cap not inserted and receptacle covers closed).

Note to paragraph (j)(2)(v) of this section. A receptacle is considered to be in a

location protected from the weather when it is located under roofed open porches,

canopies, marquees, or the like and where it will not be subjected to a beating rain or

water runoff.

1910.305(j)(2)(vi)

A receptacle installed in a wet location where the product intended to be plugged into it is

not attended while in use (for example, sprinkler system controllers, landscape lighting,

and holiday lights) shall have an enclosure that is weatherproof with the attachment plug

cap inserted or removed.

1910.305(j)(2)(vii)

A receptacle installed in a wet location where the product intended to be plugged into it

will be attended while in use (for example, portable tools) shall have an enclosure that is

weatherproof when the attachment plug cap is removed.

1910.305(j)(3)

Appliances.

1910.305(j)(3)(i)

Appliances may have no live parts normally exposed to contact other than parts

functioning as open-resistance heating elements, such as the heating elements of a

toaster, which are necessarily exposed.

1910.305(j)(3)(ii)

Each appliance shall have a means to disconnect it from all ungrounded conductors. If an

appliance is supplied by more than one source, the disconnecting means shall be grouped

and identified.

1910.305(j)(3)(iii)

Each electric appliance shall be provided with a nameplate giving the identifying name

and the rating in volts and amperes, or in volts and watts. If the appliance is to be used

108

on a specific frequency or frequencies, it shall be so marked. Where motor overload

protection external to the appliance is required, the appliance shall be so marked.

1910.305(j)(3)(iv)

Marking shall be located so as to be visible or easily accessible after installation.

1910.305(j)(4)

Motors. This paragraph applies to motors, motor circuits, and controllers.

1910.305(j)(4)(i)

If specified in paragraph (j)(4) of this section that one piece of equipment shall be "within

sight of" another piece of equipment, the piece of equipment shall be visible and not

more than 15.24 m (50.0 ft) from the other.

1910.305(j)(4)(ii)

An individual disconnecting means shall be provided for each controller. A disconnecting

means shall be located within sight of the controller location. However, a single

disconnecting means may be located adjacent to a group of coordinated controllers

mounted adjacent to each other on a multi-motor continuous process machine. The

controller disconnecting means for motor branch circuits over 600 volts, nominal, may be

out of sight of the controller, if the controller is marked with a warning label giving the

location and identification of the disconnecting means that is to be locked in the open

position.

1910.305(j)(4)(iii)

The disconnecting means shall disconnect the motor and the controller from all

ungrounded supply conductors and shall be so designed that no pole can be operated

independently.

1910.305(j)(4)(iv)

The disconnecting means shall plainly indicate whether it is in the open (off) or closed

(on) position.

109

1910.305(j)(4)(v)

The disconnecting means shall be readily accessible. If more than one disconnect is

provided for the same equipment, only one need be readily accessible.

1910.305(j)(4)(vi)

An individual disconnecting means shall be provided for each motor, but a single

disconnecting means may be used for a group of motors under any one of the following

conditions:

1910.305(j)(4)(vi)(A)

If a number of motors drive several parts of a single machine or piece of apparatus, such

as a metal or woodworking machine, crane, or hoist;

1910.305(j)(4)(vi)(B)

If a group of motors is under the protection of one set of branch-circuit protective

devices; or

1910.305(j)(4)(vi)(C)

If a group of motors is in a single room within sight of the location of the disconnecting

means.

1910.305(j)(4)(vii)

Motors, motor-control apparatus, and motor branch-circuit conductors shall be protected

against overheating due to motor overloads or failure to start, and against short-circuits

or ground faults. These provisions do not require overload protection that will stop a

motor where a shutdown is likely to introduce additional or increased hazards, as in the

case of fire pumps, or where continued operation of a motor is necessary for a safe

shutdown of equipment or process and motor overload sensing devices are connected to

a supervised alarm.

1910.305(j)(4)(viii)

Where live parts of motors or controllers operating at over 150 volts to ground are

guarded against accidental contact only by location, and where adjustment or other

attendance may be necessary during the operation of the apparatus, suitable insulating

110

mats or platforms shall be provided so that the attendant cannot readily touch live parts

unless standing on the mats or platforms.

1910.305(j)(5)

Transformers.

1910.305(j)(5)(i)

Paragraph (j)(5) of this section covers the installation of all transformers except the

following:

1910.305(j)(5)(i)(A)

Current transformers;

1910.305(j)(5)(i)(B)

Dry-type transformers installed as a component part of other apparatus;

1910.305(j)(5)(i)(C)

Transformers that are an integral part of an X-ray, high frequency, or electrostatic-

coating apparatus;

1910.305(j)(5)(i)(D)

Transformers used with Class 2 and Class 3 circuits, sign and outline lighting, electric

discharge lighting, and power-limited fire-alarm circuits; and

1910.305(j)(5)(i)(E)

Liquid-filled or dry-type transformers used for research, development, or testing, where

effective safeguard arrangements are provided.

1910.305(j)(5)(ii)

The operating voltage of exposed live parts of transformer installations shall be indicated

by signs or visible markings on the equipment or structure.

111

1910.305(j)(5)(iii)

Dry-type, high fire point liquid-insulated, and askarel-insulated transformers installed

indoors and rated over 35kV shall be in a vault.

1910.305(j)(5)(iv)

Oil-insulated transformers installed indoors shall be installed in a vault.

1910.305(j)(5)(v)

Combustible material, combustible buildings and parts of buildings, fire escapes, and door

and window openings shall be safeguarded from fires that may originate in oil-insulated

transformers attached to or adjacent to a building or combustible material.

1910.305(j)(5)(vi)

Transformer vaults shall be constructed so as to contain fire and combustible liquids

within the vault and to prevent unauthorized access. Locks and latches shall be so

arranged that a vault door can be readily opened from the inside.

1910.305(j)(5)(vii)

Any pipe or duct system foreign to the electrical installation may not enter or pass

through a transformer vault.

Note to paragraph (j)(5)(vii) of this section. Piping or other facilities provided for

vault fire protection, or for transformer cooling, are not considered foreign to the

electrical installation.

1910.305(j)(5)(viii)

Material may not be stored in transformer vaults.

1910.305(j)(6)

Capacitors.

112

1910.305(j)(6)(i)

All capacitors, except surge capacitors or capacitors included as a component part of

other apparatus, shall be provided with an automatic means of draining the stored charge

after the capacitor is disconnected from its source of supply.

1910.305(j)(6)(ii)

The following requirements apply to capacitors installed on circuits operating at more

than 600 volts, nominal:

1910.305(j)(6)(ii)(A)

Group-operated switches shall be used for capacitor switching and shall be capable of the

following:

1910.305(j)(6)(ii)(A)(1)

Carrying continuously not less than 135 percent of the rated current of the capacitor

installation;

1910.305(j)(6)(ii)(A)(2)

Interrupting the maximum continuous load current of each capacitor, capacitor bank, or

capacitor installation that will be switched as a unit;

1910.305(j)(6)(ii)(A)(3)

Withstanding the maximum inrush current, including contributions from adjacent

capacitor installations; and

1910.305(j)(6)(ii)(A)(4)

Carrying currents due to faults on the capacitor side of the switch;

1910.305(j)(6)(ii)(B)

A means shall be installed to isolate from all sources of voltage each capacitor, capacitor

bank, or capacitor installation that will be removed from service as a unit. The isolating

means shall provide a visible gap in the electric circuit adequate for the operating

voltage;

113

1910.305(j)(6)(ii)(C)

Isolating or disconnecting switches (with no interrupting rating) shall be interlocked with

the load interrupting device or shall be provided with prominently displayed caution signs

to prevent switching load current; and

1910.305(j)(6)(ii)(D)

For series capacitors, the proper switching shall be assured by use of at least one of the

following:

1910.305(j)(6)(ii)(D)(1)

Mechanically sequenced isolating and bypass switches;

1910.305(j)(6)(ii)(D)(2)

Interlocks; or

1910.305(j)(6)(ii)(D)(3)

Switching procedure prominently displayed at the switching location.

1910.305(j)(7)

Storage Batteries. Provisions shall be made for sufficient diffusion and ventilation of

gases from storage batteries to prevent the accumulation of explosive mixtures.


114


Specific purpose equipment and installations. - 1910.306



• Subpart: S



• Title: Specific purpose equipment and installations.

1910.306(a)

Electric signs and outline lighting --

1910.306(a)(1)


1910.306(a)(1)(i)

Each sign and outline lighting system, or feeder circuit or branch circuit supplying a sign

or outline lighting system, shall be controlled by an externally operable switch or circuit

breaker that will open all ungrounded conductors. However, a disconnecting means is not

required for an exit directional sign located within a building or for cord-connected signs

with an attachment plug.

1910.306(a)(1)(ii)

Signs and outline lighting systems located within fountains shall have the disconnect

located at least 1.52 m (5.0 ft) from the inside walls of the fountain.

1910.306(a)(2)

Location.

115

1910.306(a)(2)(i)

The disconnecting means shall be within sight of the sign or outline lighting system that it

controls. Where the disconnecting means is out of the line of sight from any section that

may be energized, the disconnecting means shall be capable of being locked in the open

position.

1910.306(a)(2)(ii)

Signs or outline lighting systems operated by electronic or electromechanical controllers

located external to the sign or outline lighting system may have a disconnecting means

located within sight of the controller or in the same enclosure with the controller. The

disconnecting means shall disconnect the sign or outline lighting system and the

controller from all ungrounded supply conductors. It shall be designed so no pole can be

operated independently and shall be capable of being locked in the open position.

1910.306(a)(2)(ii)

Doors or covers giving access to uninsulated parts of indoor signs or outline lighting

exceeding 600 volts and accessible to other than qualified persons shall either be

provided with interlock switches to disconnect the primary circuit or shall be so fastened

that the use of other than ordinary tools will be necessary to open them.

1910.306(b)

Cranes and hoists. This paragraph applies to the installation of electric equipment and

wiring used in connection with cranes, monorail hoists, hoists, and all runways.

1910.306(b)(1)

Disconnecting means for runway conductors. A disconnecting means shall be provided

between the runway contact conductors and the power supply. Such disconnecting means

shall consist of a motor-circuit switch, circuit breaker, or molded case switch. The

disconnecting means shall open all ungrounded conductors simultaneously and shall be:

1910.306(b)(1)(i)

Readily accessible and operable from the ground or floor level;

116

1910.306(b)(1)(ii)

Arranged to be locked in the open position; and

1910.306(b)(1)(iii)

Placed within view of the runway contact conductors.

1910.306(b)(2)

Disconnecting means for cranes and monorail hoists.

1910.306(b)(2)(i)

Except as provided in paragraph (b)(2)(iv) of this section, a motor-circuit switch, molded

case switch, or circuit breaker shall be provided in the leads from the runway contact

conductors or other power supply on all cranes and monorail hoists.

1910.306(b)(2)(ii)

The disconnecting means shall be capable of being locked in the open position.

1910.306(b)(2)(iii)

Means shall be provided at the operating station to open the power circuit to all motors of

the crane or monorail hoist where the disconnecting means is not readily accessible from

the crane or monorail hoist operating station.

1910.306(b)(2)(iv)

The disconnecting means may be omitted where a monorail hoist or hand-propelled crane

bridge installation meets all of the following conditions:

1910.306(b)(2)(iv)(A)

The unit is controlled from the ground or floor level;

1910.306(b)(2)(iv)(B)

The unit is within view of the power supply disconnecting means; and

117

1910.306(b)(2)(iv)(C)

No fixed work platform has been provided for servicing the unit.

1910.306(b)(3)

Limit switch. A limit switch or other device shall be provided to prevent the load block

from passing the safe upper limit of travel of any hoisting mechanism.

1910.306(b)(4)

Clearance. The dimension of the working space in the direction of access to live parts that

may require examination, adjustment, servicing, or maintenance while alive shall be a

minimum of 762 mm (2.5 ft). Where controls are enclosed in cabinets, the doors shall

either open at least 90 degrees or be removable.

1910.306(c)

Elevators, dumbwaiters, escalators, moving walks, wheelchair lifts, and stairway chair

lifts. The following requirements apply to elevators, dumbwaiters, escalators, moving

walks, wheelchair lifts, and stairway chair lifts.

1910.306(c)(1)

Disconnecting means. Elevators, dumbwaiters, escalators, moving walks, wheelchair lifts,

and stairway chair lifts shall have a single means for disconnecting all ungrounded main

power supply conductors for each unit.

1910.306(c)(2)

Control panels. Control panels not located in the same space as the drive machine shall

be located in cabinets with doors or panels capable of being locked closed.

1910.306(c)(3)

Type. The disconnecting means shall be an enclosed externally operable fused motor

circuit switch or circuit breaker capable of being locked in the open position. The

disconnecting means shall be a listed device.

118

1910.306(c)(4)

Operation. No provision may be made to open or close this disconnecting means from

any other part of the premises. If sprinklers are installed in hoistways, machine rooms, or

machinery spaces, the disconnecting means may automatically open the power supply to

the affected elevators prior to the application of water. No provision may be made to

close this disconnecting means automatically (that is, power may only be restored by

manual means).

1910.306(c)(5)

Location. The disconnecting means shall be located where it is readily accessible to

qualified persons.

1910.306(c)(5)(i)

On elevators without generator field control, the disconnecting means shall be located

within sight of the motor controller. Driving machines or motion and operation controllers

not within sight of the disconnecting means shall be provided with a manually operated

switch installed in the control circuit adjacent to the equipment in order to prevent

starting. Where the driving machine is located in a remote machinery space, a single

disconnecting means for disconnecting all ungrounded main power supply conductors

shall be provided and be capable of being locked in the open position.

1910.306(c)(5)(ii)

On elevators with generator field control, the disconnecting means shall be located within

sight of the motor controller for the driving motor of the motor-generator set. Driving

machines, motor-generator sets, or motion and operation controllers not within sight of

the disconnecting means shall be provided with a manually operated switch installed in

the control circuit to prevent starting. The manually operated switch shall be installed

adjacent to this equipment. Where the driving machine or the motor-generator set is

located in a remote machinery space, a single means for disconnecting all ungrounded

main power supply conductors shall be provided and be capable of being locked in the

open position.

1910.306(c)(5)(iii)

On escalators and moving walks, the disconnecting means shall be installed in the space

where the controller is located.

119

1910.306(c)(5)(iv)

On wheelchair lifts and stairway chair lifts, the disconnecting means shall be located

within sight of the motor controller.

1910.306(c)(6)

Identification and signs.

1910.306(c)(6)(i)

Where there is more than one driving machine in a machine room, the disconnecting

means shall be numbered to correspond to the identifying number of the driving machine

that they control.

1910.306(c)(6)(ii)

The disconnecting means shall be provided with a sign to identify the location of the

supply-side overcurrent protective device.

1910.306(c)(7)

Single-car and multicar installations. On single-car and multicar installations, equipment

receiving electrical power from more than one source shall be provided with a

disconnecting means for each source of electrical power. The disconnecting means shall

be within sight of the equipment served.

1910.306(c)(8)

Warning sign for multiple disconnecting means. A warning sign shall be mounted on or

next to the disconnecting means where multiple disconnecting means are used and parts

of the controllers remain energized from a source other than the one disconnected. The

sign shall be clearly legible and shall read "WARNING -- PARTS OF THE CONTROLLER ARE

NOT DEENERGIZED BY THIS SWITCH."

1910.306(c)(9)

Interconnection between multicar controllers. A warning sign worded as required in

paragraph (c)(8) of this section shall be mounted on or next to the disconnecting means

where interconnections between controllers are necessary for the operation of the system

120

on multicar installations that remain energized from a source other than the one

disconnected.

1910.306(c)(10)

Motor controllers. Motor controllers may be located outside the spaces otherwise required

by paragraph (c) of this section, provided they are in enclosures with doors or removable

panels capable of being locked closed and the disconnecting means is located adjacent to

or is an integral part of the motor controller. Motor controller enclosures for escalators or

moving walks may be located in the balustrade on the side located away from the moving

steps or moving treadway. If the disconnecting means is an integral part of the motor

controller, it shall be operable without opening the enclosure.

1910.306(d)

Electric welders -- disconnecting means --

1910.306(d)(1)

Arc welders. A disconnecting means shall be provided in the supply circuit for each arc

welder that is not equipped with a disconnect mounted as an integral part of the welder.

The disconnecting means shall be a switch or circuit breaker, and its rating may not be

less than that necessary to accommodate overcurrent protection.

1910.306(d)(2)

Resistance welders. A switch or circuit breaker shall be provided by which each resistance

welder and its control equipment can be disconnected from the supply circuit. The

ampere rating of this disconnecting means may not be less than the supply conductor

ampacity. The supply circuit switch may be used as the welder disconnecting means

where the circuit supplies only one welder.

1910.306(e)

Information technology equipment --

121

1910.306(e)(1)

Disconnecting means. A means shall be provided to disconnect power to all electronic

equipment in an information technology equipment room. There shall also be a similar

means to disconnect the power to all dedicated heating, ventilating, and air-conditioning

(HVAC) systems serving the room and to cause all required fire/smoke dampers to close.

1910.306(e)(2)

Grouping. The control for these disconnecting means shall be grouped and identified and

shall be readily accessible at the principal exit doors. A single means to control both the

electronic equipment and HVAC system is permitted.

1910.306(e)(3)

Exception. Integrated electrical systems covered by § 1910.308(g) need not have the

disconnecting means required by paragraph (e)(1) of this section.

1910.306(f)

X-Ray equipment. This paragraph applies to X-ray equipment.

1910.306(f)(1)


1910.306(f)(1)(i)

A disconnecting means shall be provided in the supply circuit. The disconnecting means

shall be operable from a location readily accessible from the X-ray control. For equipment

connected to a 120-volt branch circuit of 30 amperes or less, a grounding-type

attachment plug cap and receptacle of proper rating may serve as a disconnecting

means.

1910.306(f)(1)(ii)

If more than one piece of equipment is operated from the same high-voltage circuit, each

piece or each group of equipment as a unit shall be provided with a high-voltage switch

or equivalent disconnecting means. The disconnecting means shall be constructed,

enclosed, or located so as to avoid contact by employees with its live parts.

122

1910.306(f)(2)

Control. The following requirements apply to industrial and commercial laboratory

equipment.

1910.306(f)(2)(i)

Radiographic and fluoroscopic-type equipment shall be effectively enclosed or shall have

interlocks that deenergize the equipment automatically to prevent ready access to live

current-carrying parts.

1910.306(f)(2)(ii)

Diffraction- and irradiation-type equipment shall have a pilot light, readable meter

deflection, or equivalent means to indicate when the equipment is energized, unless the

equipment or installation is effectively enclosed or is provided with interlocks to prevent

access to live current-carrying parts during operation.

1910.306(g)

Induction and dielectric heating equipment. This paragraph applies to induction and

dielectric heating equipment and accessories for industrial and scientific applications, but

not for medical or dental applications or for appliances.

1910.306(g)(1)

Guarding and grounding.

1910.306(g)(1)(i)

The converting apparatus (including the dc line) and high-frequency electric circuits

(excluding the output circuits and remote-control circuits) shall be completely contained

within enclosures of noncombustible material.

1910.306(g)(1)(ii)

All panel controls shall be of dead-front construction.

123

1910.306(g)(1)(iii)

Doors or detachable panels shall be employed for internal access. Where doors are used

giving access to voltages from 500 to 1000 volts ac or dc, either door locks shall be

provided or interlocks shall be installed. Where doors are used giving access to voltages

of over 1000 volts ac or dc, either mechanical lockouts with a disconnecting means to

prevent access until circuit parts within the cubicle are deenergized, or both door

interlocking and mechanical door locks, shall be provided. Detachable panels not normally

used for access to such parts shall be fastened in a manner that will make them difficult

to remove (for example, by requiring the use of tools).

1910.306(g)(1)(iv)

Warning labels or signs that read "DANGER -- HIGH VOLTAGE -- KEEP OUT" shall be

attached to the equipment and shall be plainly visible where persons might contact

energized parts when doors are opened or closed or when panels are removed from

compartments containing over 250 volts ac or dc.

1910.306(g)(1)(v)

Induction and dielectric heating equipment shall be protected as follows:

1910.306(g)(1)(v)(A)

Protective cages or adequate shielding shall be used to guard work applicators other than

induction heating coils.

1910.306(g)(1)(v)(B)

Induction heating coils shall be protected by insulation or refractory materials or both.

1910.306(g)(1)(v)(C)

Interlock switches shall be used on all hinged access doors, sliding panels, or other such

means of access to the applicator, unless the applicator is an induction heating coil at dc

ground potential or operating at less than 150 volts ac.

1910.306(g)(1)(v)(D)

Interlock switches shall be connected in such a manner as to remove all power from the

applicator when any one of the access doors or panels is open.

124

1910.306(g)(1)(vi)

A readily accessible disconnecting means shall be provided by which each heating

equipment can be isolated from its supply circuit. The ampere rating of this disconnecting

means may not be less than the nameplate current rating of the equipment. The supply

circuit disconnecting means is permitted as a heating equipment disconnecting means

where the circuit supplies only one piece of equipment.

1910.306(g)(2)

Remote control.

1910.306(g)(2)(i)

If remote controls are used for applying power, a selector switch shall be provided and

interlocked to provide power from only one control point at a time.

1910.306(g)(2)(ii)

Switches operated by foot pressure shall be provided with a shield over the contact

button to avoid accidental closing of the switch.

1910.306(h)

Electrolytic cells. This paragraph applies to the installation of the electrical components

and accessory equipment of electrolytic cells, electrolytic cell lines, and process power

supply for the production of aluminum, cadmium, chlorine, copper, fluorine, hydrogen

peroxide, magnesium, sodium, sodium chlorate, and zinc. Cells used as a source of

electric energy and for electroplating processes and cells used for production of hydrogen

are not covered by this paragraph.

1910.306(h)(1)

Application. Installations covered by paragraph (h) of this section shall comply with all

applicable provisions of this subpart, except as follows:

1910.306(h)(1)(i)

Overcurrent protection of electrolytic cell dc process power circuits need not comply with

the requirements of § 1910.304(f);

125

1910.306(h)(1)(ii)

Equipment located or used within the cell line working zone or associated with the cell

line dc power circuits need not comply with the provisions of § 1910.304(g); and

1910.306(h)(1)(iii)

Electrolytic cells, cell line conductors, cell line attachments, and the wiring of auxiliary

equipment and devices within the cell line working zone need not comply with the

provisions of § 1910.303 or § 1910.304(b) and (c).

1910.306(h)(2)

Disconnecting means. If more than one dc cell line process power supply serves the same

cell line, a disconnecting means shall be provided on the cell line circuit side of each

power supply to disconnect it from the cell line circuit. Removable links or removable

conductors may be used as the disconnecting means.

1910.306(h)(3)

Portable electric equipment.

1910.306(h)(3)(i)

The frames and enclosures of portable electric equipment used within the cell line

working zone may not be grounded, unless the cell line circuit voltage does not exceed

200 volts DC or the frames are guarded.

1910.306(h)(3)(ii)

Ungrounded portable electric equipment shall be distinctively marked and shall employ

plugs and receptacles of a configuration that prevents connection of this equipment to

grounding receptacles and that prevents inadvertent interchange of ungrounded and

grounded portable electric equipment.

1910.306(h)(4)

Power supply circuits and receptacles for portable electric equipment.

126

1910.306(h)(4)(i)

Circuits supplying power to ungrounded receptacles for hand-held, cord- and plug-

connected equipment shall meet the following requirements:

1910.306(h)(4)(i)(A)

The circuits shall be electrically isolated from any distribution system supplying areas

other than the cell line working zone and shall be ungrounded;

1910.306(h)(4)(i)(B)

The circuits shall be supplied through isolating transformers with primaries operating at

not more than 600 volts between conductors and protected with proper overcurrent

protection;

1910.306(h)(4)(i)(C)

The secondary voltage of the isolating transformers may not exceed 300 volts between

conductors; and

1910.306(h)(4)(i)(D)

All circuits supplied from the secondaries shall be ungrounded and shall have an

approved overcurrent device of proper rating in each conductor.

1910.306(h)(4)(ii)

Receptacles and their mating plugs for ungrounded equipment may not have provision for

a grounding conductor and shall be of a configuration that prevents their use for

equipment required to be grounded.

1910.306(h)(4)(iii)

Receptacles on circuits supplied by an isolating transformer with an ungrounded

secondary:

1910.306(h)(4)(iii)(A)

Shall have a distinctive configuration;

127

1910.306(h)(4)(iii)(B)

Shall be distinctively marked; and

1910.306(h)(4)(iii)(C)

May not be used in any other location in the facility.

1910.306(h)(5)

Fixed and portable electric equipment.

1910.306(h)(5)(i)

The following need not be grounded:

1910.306(h)(5)(i)(A)

AC systems supplying fixed and portable electric equipment within the cell line working

zone; and

1910.306(h)(5)(i)(B)

Exposed conductive surfaces, such as electric equipment housings, cabinets, boxes,

motors, raceways and the like that are within the cell line working zone.

1910.306(h)(5)(ii)

Auxiliary electric equipment, such as motors, transducers, sensors, control devices, and

alarms, mounted on an electrolytic cell or other energized surface shall be connected to

the premises wiring systems by any of the following means:

1910.306(h)(5)(ii)(A)

Multiconductor hard usage or extra hard usage flexible cord;

1910.306(h)(5)(ii)(B)

Wire or cable in suitable nonmetallic raceways or cable trays; or

128

1910.306(h)(5)(ii)(C)

Wire or cable in suitable metal raceways or metal cable trays installed with insulating

breaks such that they will not cause a potentially hazardous electrical condition.

1910.306(h)(5)(iii)

Fixed electric equipment may be bonded to the energized conductive surfaces of the cell

line, its attachments, or auxiliaries. if fixed electric equipment is mounted on an

energized conductive surface, it shall be bonded to that surface.

1910.306(h)(6)

Auxiliary nonelectrical connections. Auxiliary nonelectrical connections such as air hoses,

water hoses, and the like, to an electrolytic cell, its attachments, or auxiliary equipment

may not have continuous conductive reinforcing wire, armor, braids, or the like. Hoses

shall be of a nonconductive material.

1910.306(h)(7)

Cranes and hoists.

1910.306(h)(7)(i)

The conductive surfaces of cranes and hoists that enter the cell line working zone need

not be grounded. The portion of an overhead crane or hoist that contacts an energized

electrolytic cell or energized attachments shall be insulated from ground.

1910.306(h)(7)(ii)

Remote crane or hoist controls that may introduce hazardous electrical conditions into the

cell line working zone shall employ one or more of the following systems:

1910.306(h)(7)(ii)(A)

Isolated and ungrounded control circuit;

1910.306(h)(7)(ii)(B)

Nonconductive rope operator;

129

1910.306(h)(7)(ii)(C)

Pendant pushbutton with nonconductive supporting means and with nonconductive

surfaces or ungrounded exposed conductive surfaces; or

1910.306(h)(7)(ii)(D)

Radio.

1910.306(i)

Electrically driven or controlled irrigation machines --

1910.306(i)(1)

Lightning protection. If an irrigation machine has a stationary point, a grounding

electrode system shall be connected to the machine at the stationary point for lightning

protection.

1910.306(i)(2)


1910.306(i)(2)(i)

The main disconnecting means for a center pivot irrigation machine shall be located at

the point of connection of electrical power to the machine or shall be visible and not more

than 15.2 m (50 ft) from the machine.

1910.306(i)(2)(ii)

The disconnecting means shall be readily accessible and capable of being locked in the

open position.

1910.306(i)(2)(iii)

A disconnecting means shall be provided for each motor and controller.

130

1910.306(j)

Swimming pools, fountains, and similar installations. This paragraph applies to electric

wiring for and equipment in or adjacent to all swimming, wading, therapeutic, and

decorative pools and fountains; hydro-massage bathtubs, whether permanently installed

or storable; and metallic auxiliary equipment, such as pumps, filters, and similar

equipment. Therapeutic pools in health care facilities are exempt from these provisions.

1910.306(j)(1)

Receptacles.

1910.306(j)(1)(i)

A single receptacle of the locking and grounding type that provides power for a

permanently installed swimming pool recirculating pump motor may be located not less

than 1.52 m (5 ft) from the inside walls of a pool. All other receptacles on the property

shall be located at least 3.05 m (10 ft) from the inside walls of a pool.

1910.306(j)(1)(ii)

Receptacles that are located within 4.57 m (15 ft), or 6.08 m (20 ft) if the installation

was built after August 13, 2007, of the inside walls of the pool shall be protected by

ground-fault circuit interrupters.

1910.306(j)(1)(iii)

Where a pool is installed permanently at a dwelling unit, at least one 125-volt, 15- or 20-

ampere receptacle on a general-purpose branch circuit shall be located a minimum of

3.05 m (10 ft) and not more than 6.08 m (20 ft) from the inside wall of the pool. This

receptacle shall be located not more than 1.98 m (6.5 ft) above the floor, platform, or

grade level serving the pool.

Note to paragraph (j)(1) of this section: In determining these dimensions, the

distance to be measured is the shortest path the supply cord of an appliance connected

to the receptacle would follow without piercing a floor, wall, or ceiling of a building or

other effective permanent barrier.

131

1910.306(j)(2)

Lighting fixtures, lighting outlets, and ceiling suspended (paddle) fans.

1910.306(j)(2)(i)

In outdoor pool areas, lighting fixtures, lighting outlets, and ceiling-suspended (paddle)

fans may not be installed over the pool or over the area extending 1.52 m (5 ft)

horizontally from the inside walls of a pool unless no part of the lighting fixture of a

ceiling-suspended (paddle) fan is less than 3.66 m (12 ft) above the maximum water

level. However, a lighting fixture or lighting outlet that was installed before April 16,

1981, may be located less than 1.52 m (5 ft) measured horizontally from the inside walls

of a pool if it is at least 1.52 m (5 ft) above the surface of the maximum water level and

is rigidly attached to the existing structure. It shall also be protected by a ground-fault

circuit interrupter installed in the branch circuit supplying the fixture.

1910.306(j)(2)(ii)

Lighting fixtures and lighting outlets installed in the area extending between 1.52 m (5 ft)

and 3.05 m (10 ft) horizontally from the inside walls of a pool shall be protected by a

ground-fault circuit interrupter unless installed 1.52 m (5 ft) above the maximum water

level and rigidly attached to the structure adjacent to or enclosing the pool.

1910.306(j)(3)

Cord- and plug-connected equipment. Flexible cords used with the following equipment

may not exceed 0.9 m (3 ft) in length and shall have a copper equipment grounding

conductor with a grounding-type attachment plug:

1910.306(j)(3)(i)

Cord- and plug-connected lighting fixtures installed within 4.88 m (16 ft) of the water

surface of permanently installed pools; and

1910.306(j)(3)(ii)

Other cord- and plug-connected, fixed or stationary equipment used with permanently

installed pools.

132

1910.306(j)(4)

Underwater equipment.

1910.306(j)(4)(i)

A ground-fault circuit interrupter shall be installed in the branch circuit supplying

underwater fixtures operating at more than 15 volts. Equipment installed underwater

shall be identified for the purpose.

1910.306(j)(4)(ii)

No underwater lighting fixtures may be installed for operation at over 150 volts between

conductors.

1910.306(j)(4)(iii)

A lighting fixture facing upward shall have the lens adequately guarded to prevent

contact by any person.

1910.306(j)(5)

Fountains. All electric equipment, including power supply cords, operating at more than

15 volts and used with fountains shall be protected by ground-fault circuit interrupters.

1910.306(k)

Carnivals, circuses, fairs, and similar events. This paragraph covers the installation of

portable wiring and equipment, including wiring in or on all structures, for carnivals,

circuses, exhibitions, fairs, traveling attractions, and similar events.

1910.306(k)(1)

Protection of electric equipment. Electric equipment and wiring methods in or on rides,

concessions, or other units shall be provided with mechanical protection where such

equipment or wiring methods are subject to physical damage.

1910.306(k)(2)

Installation.

133

1910.306(k)(2)(i)

Services shall be installed in accordance with applicable requirements of this subpart,

and, in addition, shall comply with the following:

1910.306(k)(2)(i)(A)

Service equipment may not be installed in a location that is accessible to unqualified

persons, unless the equipment is lockable; and

1910.306(k)(2)(i)(B)

Service equipment shall be mounted on solid backing and installed so as to be protected

from the weather, unless the equipment is of weatherproof construction.

1910.306(k)(2)(ii)

Amusement rides and amusement attractions shall be maintained not less than 4.57 m

(15 ft) in any direction from overhead conductors operating at 600 volts or less, except

for the conductors supplying the amusement ride or attraction. Amusement rides or

attractions may not be located under or within 4.57 m (15 ft) horizontally of conductors

operating in excess of 600 volts.

1910.306(k)(2)(iii)

Flexible cords and cables shall be listed for extra-hard usage. When used outdoors,

flexible cords and cables shall also be listed for wet locations and shall be sunlight

resistant.

1910.306(k)(2)(iv)

Single conductor cable shall be size No. 2 or larger.

1910.306(k)(2)(iv)

Open conductors are prohibited except as part of a listed assembly or festoon lighting

installed in accordance with § 1910.304(c).

1910.306(k)(2)(vi)

134

Flexible cords and cables shall be continuous without splice or tap between boxes or

fittings. Cord connectors may not be laid on the ground unless listed for wet locations.

Connectors and cable connections may not be placed in audience traffic paths or within

areas accessible to the public unless guarded.

1910.306(k)(2)(vii)

Wiring for an amusement ride, attraction, tent, or similar structure may not be supported

by another ride or structure unless specifically identified for the purpose.

1910.306(k)(2)(viii)

Flexible cords and cables run on the ground, where accessible to the public, shall be

covered with approved nonconductive mats. Cables and mats shall be arranged so as not

to present a tripping hazard.

1910.306(k)(2)(ix)

A box or fitting shall be installed at each connection point, outlet, switch point, or

junction point.

1910.306(k)(3)

Inside tents and concessions. Electrical wiring for temporary lighting, where installed

inside of tents and concessions, shall be securely installed, and, where subject to physical

damage, shall be provided with mechanical protection. All temporary lamps for general

illumination shall be protected from accidental breakage by a suitable fixture or

lampholder with a guard.

1910.306(k)(4)

Portable distribution and termination boxes. Employers may only use portable distribution

and termination boxes that meet the following requirements:

1910.306(k)(4)(i)

Boxes shall be designed so that no live parts are exposed to accidental contact. Where

installed outdoors, the box shall be of weatherproof construction and mounted so that the

bottom of the enclosure is not less than 152 mm (6 in.) above the ground;

135

1910.306(k)(4)

Busbars shall have an ampere rating not less than the overcurrent device supplying the

feeder supplying the box. Busbar connectors shall be provided where conductors

terminate directly on busbars;

1910.306(k)(4)(iii)

Receptacles shall have overcurrent protection installed within the box. The overcurrent

protection may not exceed the ampere rating of the receptacle, except as permitted in §

1910.305(j)(4) for motor loads;

1910.306(k)(4)(iv)

Where single-pole connectors are used, they shall comply with the following:

1910.306(k)(4)(iv)(A)

Where ac single-pole portable cable connectors are used, they shall be listed and of the

locking type. Where paralleled sets of current-carrying single-pole separable connectors

are provided as input devices, they shall be prominently labeled with a warning indicating

the presence of internal parallel connections. The use of single-pole separable connectors

shall comply with at least one of the following conditions:

1910.306(k)(4)(iv)(A)(1)

Connection and disconnection of connectors are only possible where the supply

connectors are interlocked to the source and it is not possible to connect or disconnect

connectors when the supply is energized; or

1910.306(k)(4)(iv)(A)(2)

Line connectors are of the listed sequential-interlocking type so that load connectors are

connected in the following sequence:

1910.306(k)(4)(iv)(A)(2)(i)

Equipment grounding conductor connection;

1910.306(k)(4)(iv)(A)(2)(ii)

Grounded circuit-conductor connection, if provided; and

136

1910.306(k)(4)(iv)(A)(2)(iii)

Ungrounded conductor connection; and so that disconnection is in the reverse order; or

1910.306(k)(4)(iv)(A)(3)

A caution notice is provided adjacent to the line connectors indicating that plug

connection must be in the following sequence:

1910.306(k)(4)(iv)(A)(3)(i)

Equipment grounding conductor connection;

1910.306(k)(4)(iv)(A)(3)(ii)

Grounded circuit-conductor connection, if provided; and

1910.306(k)(4)(iv)(A)(3)(iii)

Ungrounded conductor connection; and indicating that disconnection is in the reverse

order; and

1910.306(k)(4)(iv)(B)

Single-pole separable connectors used in portable professional motion picture and

television equipment may be interchangeable for ac or dc use or for different current

ratings on the same premises only if they are listed for ac/dc use and marked to identify

the system to which they are connected;

1910.306(k)(4)(v)

Overcurrent protection of equipment and conductors shall be provided; and

1910.306(k)(4)(vi)

The following equipment connected to the same source shall be bonded:

1910.306(k)(4)(vi)(A)

Metal raceways and metal sheathed cable;

137

1910.306(k)(4)(vi)(B)

Metal enclosures of electrical equipment; and

1910.306(k)(4)(vi)(C)

Metal frames and metal parts of rides, concessions, trailers, trucks, or other equipment

that contain or support electrical equipment.

1910.306(k)(5)


1910.306(k)(5)(i)

Each ride and concession shall be provided with a fused disconnect switch or circuit

breaker located within sight and within 1.83 m (6 ft) of the operator's station.

1910.306(k)(5)(ii)

The disconnecting means shall be readily accessible to the operator, including when the

ride is in operation.

1910.306(k)(5)(iii)

Where accessible to unqualified persons, the enclosure for the switch or circuit breaker

shall be of the lockable type.

1910.306(k)(5)(iv)

A shunt trip device that opens the fused disconnect or circuit breaker when a switch

located in the ride operator's console is closed is a permissible method of opening the

circuit.


138


Hazardous (classified) locations. - 1910.307



• Subpart: S



• Title: Hazardous (classified) locations.

1910.307(a)

Scope --

1910.307(a)(1)

Applicability. This section covers the requirements for electric equipment and wiring in

locations that are classified depending on the properties of the flammable vapors, liquids

or gases, or combustible dusts or fibers that may be present therein and the likelihood

that a flammable or combustible concentration or quantity is present. Hazardous

(classified) locations may be found in occupancies such as, but not limited to, the

following: aircraft hangars, gasoline dispensing and service stations, bulk storage plants

for gasoline or other volatile flammable liquids, paint-finishing process plants, health care

facilities, agricultural or other facilities where excessive combustible dusts may be

present, marinas, boat yards, and petroleum and chemical processing plants. Each room,

section or area shall be considered individually in determining its classification.

1910.307(a)(2)

Classifications.

1910.307(a)(2)(i)

These hazardous (classified) locations are assigned the following designations:

139

1910.307(a)(2)(i)(A)

Class I, Division 1

1910.307(a)(2)(i)(B)

Class I, Division 2

1910.307(a)(2)(i)(C)

Class I, Zone 0

1910.307(a)(2)(i)(D)

Class I, Zone 1

1910.307(a)(2)(i)(E)

Class I, Zone 2

1910.307(a)(2)(i)(F)

Class II, Division 1

1910.307(a)(2)(i)(G)

Class II, Division 2

1910.307(a)(2)(i)(H)

Class III, Division 1

1910.307(a)(2)(i)(I)

Class III, Division 2

1910.307(a)(2)(ii)

For definitions of these locations, see § 1910.399.

140

1910.307(a)(3)

Other sections of this subpart. All applicable requirements in this subpart apply to

hazardous (classified) locations unless modified by provisions of this section.

1910.307(a)(4)

Division and zone classification. In Class I locations, an installation must be classified as

using the division classification system meeting paragraphs (c), (d), (e), and (f) of this

section or using the zone classification system meeting paragraph (g) of this section. In

Class II and Class III locations, an installation must be classified using the division

classification system meeting paragraphs (c), (d), (e), and (f) of this section.

1910.307(b)

Documentation. All areas designated as hazardous (classified) locations under the Class

and Zone system and areas designated under the Class and Division system established

after August 13, 2007 shall be properly documented. This documentation shall be

available to those authorized to design, install, inspect, maintain, or operate electric

equipment at the location.

1910.307(c)

Electrical installations. Equipment, wiring methods, and installations of equipment in

hazardous (classified) locations shall be intrinsically safe, approved for the hazardous

(classified) location, or safe for the hazardous (classified) location. Requirements for each

of these options are as follows:

1910.307(c)(1)

Intrinsically safe. Equipment and associated wiring approved as intrinsically safe is

permitted in any hazardous (classified) location for which it is approved;

1910.307(c)(2)

Approved for the hazardous (classified) location.

141

1910.307(c)(2)(i)

Equipment shall be approved not only for the class of location, but also for the ignitable

or combustible properties of the specific gas, vapor, dust, or fiber that will be present.

Note to paragraph (c)(2)(i) of this section: NFPA 70, the National Electrical Code,

lists or defines hazardous gases, vapors, and dusts by "Groups" characterized by their

ignitable or combustible properties.

1910.307(c)(2)(ii)

Equipment shall be marked to show the class, group, and operating temperature or

temperature range, based on operation in a 40-degree C ambient, for which it is

approved. The temperature marking may not exceed the ignition temperature of the

specific gas or vapor to be encountered. However, the following provisions modify this

marking requirement for specific equipment:

1910.307(c)(2)(ii)(A)

Equipment of the nonheat-producing type, such as junction boxes, conduit, and fittings,

and equipment of the heat-producing type having a maximum temperature not more

than 100º C (212º F) need not have a marked operating temperature or temperature

range;

1910.307(c)(2)(ii)(B)

Fixed lighting fixtures marked for use in Class I, Division 2 or Class II, Division 2

locations only need not be marked to indicate the group;

1910.307(c)(2)(ii)(C)

Fixed general-purpose equipment in Class I locations, other than lighting fixtures, that is

acceptable for use in Class I, Division 2 locations need not be marked with the class,

group, division, or operating temperature;

1910.307(c)(2)(ii)(D)

Fixed dust-tight equipment, other than lighting fixtures, that is acceptable for use in

Class II, Division 2 and Class III locations need not be marked with the class, group,

division, or operating temperature; and

142

1910.307(c)(2)(ii)(E)

Electric equipment suitable for ambient temperatures exceeding 40º C (104º F) shall be

marked with both the maximum ambient temperature and the operating temperature or

temperature range at that ambient temperature; and

1910.307(c)(3)

Safe for the hazardous (classified) location. Equipment that is safe for the location shall

be of a type and design that the employer demonstrates will provide protection from the

hazards arising from the combustibility and flammability of vapors, liquids, gases, dusts,

or fibers involved.

Note to paragraph (c)(3) of this section: The National Electrical Code, NFPA 70,

contains guidelines for determining the type and design of equipment and installations

that will meet this requirement. Those guidelines address electric wiring, equipment, and

systems installed in hazardous (classified) locations and contain specific provisions for the

following: wiring methods, wiring connections; conductor insulation, flexible cords,

sealing and drainage, transformers, capacitors, switches, circuit breakers, fuses, motor

controllers, receptacles, attachment plugs, meters, relays, instruments, resistors,

generators, motors, lighting fixtures, storage battery charging equipment, electric cranes,

electric hoists and similar equipment, utilization equipment, signaling systems, alarm

systems, remote control systems, local loud speaker and communication systems,

ventilation piping, live parts, lightning surge protection, and grounding.

1910.307(d)

Conduits. All conduits shall be threaded and shall be made wrench-tight. Where it is

impractical to make a threaded joint tight, a bonding jumper shall be utilized.

1910.307(e)

Equipment in Division 2 locations. Equipment that has been approved for a Division 1

location may be installed in a Division 2 location of the same class and group. General-

purpose equipment or equipment in general-purpose enclosures may be installed in

Division 2 locations if the employer can demonstrate that the equipment does not

constitute a source of ignition under normal operating conditions.

143

1910.307(f)

Protection techniques. The following are acceptable protection techniques for electric and

electronic equipment in hazardous (classified) locations.

1910.307(f)(1)

Explosionproof apparatus. This protection technique is permitted for equipment in the

Class I, Division 1 and 2 locations for which it is approved.

1910.307(f)(2)

Dust ignitionproof. This protection technique is permitted for equipment in the Class II,

Division 1 and 2 locations for which it is approved.

1910.307(f)(3)

Dust-tight. This protection technique is permitted for equipment in the Class II, Division 2

and Class III locations for which it is approved.

1910.307(f)(4)

Purged and pressurized. This protection technique is permitted for equipment in any

hazardous (classified) location for which it is approved.

1910.307(f)(5)

Nonincendive circuit. This protection technique is permitted for equipment in Class I,

Division 2; Class II, Division 2; or Class III, Division 1or 2 locations.

1910.307(f)(6)

Nonincendive equipment. This protection technique is permitted for equipment in Class I,

Division 2; Class II, Division 2; or Class III, Division 1 or 2 locations.

1910.307(f)(7)

Nonincendive component. This protection technique is permitted for equipment in Class I,

Division 2; Class II, Division 2; or Class III, Division 1 or 2 locations.

144

1910.307(f)(8)

Oil immersion. This protection technique is permitted for current-interrupting contacts in

Class I, Division 2 locations as described in the Subpart.

1910.307(f)(9)

Hermetically sealed. This protection technique is permitted for equipment in Class I,

Division 2; Class II, Division 2; and Class III, Division 1 or 2 locations.

1910.307(f)(10)

Other protection techniques. Any other protection technique that meets paragraph (c) of

this section is acceptable in any hazardous (classified) location.

1910.307(g)

Class I, Zone 0, 1, and 2 locations --

1910.307(g)(1)

Scope. Employers may use the zone classification system as an alternative to the division

classification system for electric and electronic equipment and wiring for all voltage in

Class I, Zone 0, Zone 1, and Zone 2 hazardous (classified) locations where fire or

explosion hazards may exist due to flammable gases, vapors, or liquids.

1910.307(g)(2)

Location and general requirements.

1910.307(g)(2)(i)

Locations shall be classified depending on the properties of the flammable vapors, liquids,

or gases that may be present and the likelihood that a flammable or combustible

concentration or quantity is present. Where pyrophoric materials are the only materials

used or handled, these locations need not be classified.

1910.307(g)(2)(ii)

Each room, section, or area shall be considered individually in determining its

classification.

145

1910.307(g)(2)(iii)

All threaded conduit shall be threaded with an NPT (National (American) Standard Pipe

Taper) standard conduit cutting die that provides 3/4-in. taper per foot. The conduit shall

be made wrench tight to prevent sparking when fault current flows through the conduit

system and to ensure the explosionproof or flameproof integrity of the conduit system

where applicable.

1910.307(g)(2)(iv)

Equipment provided with threaded entries for field wiring connection shall be installed in

accordance with paragraph (g)(2)(iv)(A) or (g)(2)(iv)(B) of this section.

1910.307(g)(2)(iv)(A)

For equipment provided with threaded entries for NPT threaded conduit or fittings, listed

conduit, conduit fittings, or cable fittings shall be used.

1910.307(g)(2)(iv)(B)

For equipment with metric threaded entries, such entries shall be identified as being

metric, or listed adaptors to permit connection to conduit of NPT-threaded fittings shall

be provided with the equipment. Adapters shall be used for connection to conduit or NPT-

threaded fittings.

1910.307(g)(3)

Protection techniques. One or more of the following protection techniques shall be used

for electric and electronic equipment in hazardous (classified) locations classified under

the zone classification system.

1910.307(g)(3)(i)

Flameproof "d" -- This protection technique is permitted for equipment in the Class I,

Zone 1 locations for which it is approved.

1910.307(g)(3)(ii)

Purged and pressurized -- This protection technique is permitted for equipment in the

Class I, Zone 1 or Zone 2 locations for which it is approved.

146

1910.307(g)(3)(iii)

Intrinsic safety -- This protection technique is permitted for equipment in the Class I,

Zone 0 or Zone 1 locations for which it is approved.

1910.307(g)(3)(iv)

Type of protection "n" -- This protection technique is permitted for equipment in the Class

I, Zone 2 locations for which it is approved. Type of protection "n" is further subdivided

into nA, nC, and nR.

1910.307(g)(3)(v)

Oil Immersion "o" -- This protection technique is permitted for equipment in the Class I,


1910.307(g)(3)(vi)

Increased safety "e" -- This protection technique is permitted for equipment in the Class

I, Zone 1 locations for which it is approved.

1910.307(g)(3)(vii)

Encapsulation "m" -- This protection technique is permitted for equipment in the Class I,


1910.307(g)(3)(viii)

Powder Filling "q" -- This protection technique is permitted for equipment in the Class I,


1910.307(g)(4)

Special precaution. Paragraph (g) of this section requires equipment construction and

installation that will ensure safe performance under conditions of proper use and

maintenance.

1910.307(g)(4)(i)

Classification of areas and selection of equipment and wiring methods shall be under the

supervision of a qualified registered professional engineer.

147

1910.307(g)(4)(ii)

In instances of areas within the same facility classified separately, Class I, Zone 2

locations may abut, but not overlap, Class I, Division 2 locations. Class I, Zone 0 or Zone

1 locations may not abut Class I, Division 1 or Division 2 locations.

1910.307(g)(4)(iii)

A Class I, Division 1 or Division 2 location may be reclassified as a Class I, Zone 0, Zone

1, or Zone 2 location only if all of the space that is classified because of a single

flammable gas or vapor source is reclassified.

Note to paragraph (g)(4) of this section: Low ambient conditions require special

consideration. Electric equipment depending on the protection techniques described by

paragraph (g)(3)(i) of this section may not be suitable for use at temperatures lower

than -20 ºC (-4 ºF) unless they are approved for use at lower temperatures. However, at

low ambient temperatures, flammable concentrations of vapors may not exist in a

location classified Class I, Zone 0, 1, or 2 at normal ambient temperature.

1910.307(g)(5)

Listing and marking.

1910.307(g)(5)(i)

Equipment that is listed for a Zone 0 location may be installed in a Zone 1 or Zone 2

location of the same gas or vapor. Equipment that is listed for a Zone 1 location may be

installed in a Zone 2 location of the same gas or vapor.

1910.307(g)(5)(ii)

Equipment shall be marked in accordance with paragraph (g)(5)(ii)(A) and (g)(5)(ii)(B)

of this section, except as provided in (g)(5)(ii)(C).

1910.307(g)(5)(ii)(A)

Equipment approved for Class I, Division 1 or Class 1, Division 2 shall, in addition to

being marked in accordance with (c)(2)(ii), be marked with the following:

148

1910.307(g)(5)(ii)(A)(1)

Class I, Zone 1 or Class I, Zone 2 (as applicable);

1910.307(g)(5)(ii)(A)(2)

Applicable gas classification groups; and

1910.307(g)(5)(ii)(A)(3)

Temperature classification; or

1910.307(g)(5)(ii)(B)

Equipment meeting one or more of the protection techniques described in paragraph

(g)(3) of this section shall be marked with the following in the order shown:

1910.307(g)(5)(ii)(B)(1)

Class, except for intrinsically safe apparatus;

1910.307(g)(5)(ii)(B)(2)

Zone, except for intrinsically safe apparatus;

1910.307(g)(5)(ii)(B)(3)

Symbol "AEx;"

1910.307(g)(5)(ii)(B)(4)

Protection techniques;

1910.307(g)(5)(ii)(B)(5)

Applicable gas classification groups; and

1910.307(g)(5)(ii)(B)(6)

Temperature classification, except for intrinsically safe apparatus.

Note to paragraph (g)(5)(ii)(B) of this section: An example of such a required

149

marking is "Class I, Zone 0, AEx ia IIC T6." See Figure S-1 for an explanation of this

marking.

1910.307(g)(5)(ii)(C)

Equipment that the employer demonstrates will provide protection from the hazards

arising from the flammability of the gas or vapor and the zone of location involved and

will be recognized as providing such protection by employees need not be marked.

Note to paragraph (g)(5)(ii)(C) of this section: The National Electrical Code, NFPA

70, contains guidelines for determining the type and design of equipment and

installations that will meet this provision.


150


Special systems. - 1910.308



• Subpart: S



• Title: Special systems.

1910.308(a)

Systems over 600 volts, nominal. This paragraph covers the general requirements for all

circuits and equipment operated at over 600 volts.

1910.308(a)(1)

Aboveground wiring methods.

1910.308(a)(1)(i)

Aboveground conductors shall be installed in rigid metal conduit, in intermediate metal

conduit, in electrical metallic tubing, in rigid nonmetallic conduit, in cable trays, as

busways, as cablebus, in other identified raceways, or as open runs of metal-clad cable

suitable for the use and purpose. In locations accessible to qualified persons only, open

runs of Type MV cables, bare conductors, and bare busbars are also permitted. Busbars

shall be either copper or aluminum. Open runs of insulated wires and cables having a

bare lead sheath or a braided outer covering shall be supported in a manner designed to

prevent physical damage to the braid or sheath.

1910.308(a)(1)(ii)

Conductors emerging from the ground shall be enclosed in approved raceways.

151

1910.308(a)(2)

Braid-covered insulated conductors -- open installations. The braid on open runs of braid-

covered insulated conductors shall be flame retardant or shall have a flame-retardant

saturant applied after installation. This treated braid covering shall be stripped back a

safe distance at conductor terminals, according to the operating voltage.

1910.308(a)(3)

Insulation shielding.

1910.308(a)(3)(i)

Metallic and semiconductor insulation shielding components of shielded cables shall be

removed for a distance dependent on the circuit voltage and insulation. Stress reduction

means shall be provided at all terminations of factory-applied shielding.

1910.308(a)(3)(ii)

Metallic shielding components such as tapes, wires, or braids, or combinations thereof,

and their associated conducting and semiconducting components shall be grounded.

1910.308(a)(4)

Moisture or mechanical protection for metal-sheathed cables. Where cable conductors

emerge from a metal sheath and where protection against moisture or physical damage

is necessary, the insulation of the conductors shall be protected by a cable sheath

terminating device.

1910.308(a)(5)

Interrupting and isolating devices.

1910.308(a)(5)(i)

Circuit breaker installations located indoors shall consist of metal-enclosed units or fire-

resistant cell-mounted units. In locations accessible only to qualified employees, open

mounting of circuit breakers is permitted. A means of indicating the open and closed

position of circuit breakers shall be provided.

152

1910.308(a)(5)(ii)

Where fuses are used to protect conductors and equipment, a fuse shall be placed in each

ungrounded conductor. Two power fuses may be used in parallel to protect the same

load, if both fuses have identical ratings, and if both fuses are installed in an identified

common mounting with electrical connections that will divide the current equally. Power

fuses of the vented type may not be used indoors, underground, or in metal enclosures

unless identified for the use.

1910.308(a)(5)(iii)

Fused cutouts installed in buildings or transformer vaults shall be of a type identified for

the purpose. Distribution cutouts may not be used indoors, underground, or in metal

enclosures. They shall be readily accessible for fuse replacement.

1910.308(a)(5)(iv)

Where fused cutouts are not suitable to interrupt the circuit manually while carrying full

load, an approved means shall be installed to interrupt the entire load. Unless the fused

cutouts are interlocked with the switch to prevent opening of the cutouts under load, a

conspicuous sign shall be placed at such cutouts reading: "WARNING -- DO NOT

OPERATE UNDER LOAD."

1910.308(a)(5)(v)

Suitable barriers or enclosures shall be provided to prevent contact with nonshielded

cables or energized parts of oil-filled cutouts.

1910.308(a)(5)(vi)

Load interrupter switches may be used only if suitable fuses or circuits are used in

conjunction with these devices to interrupt fault currents.

1910.308(a)(5)(vi)(A)

Where these devices are used in combination, they shall be coordinated electrically so

that they will safely withstand the effects of closing, carrying, or interrupting all possible

currents up to the assigned maximum short-circuit rating.

153

1910.308(a)(5)(vi)(B)

Where more than one switch is installed with interconnected load terminals to provide for

alternate connection to different supply conductors, each switch shall be provided with a

conspicuous sign reading: "WARNING -- SWITCH MAY BE ENERGIZED BY BACKFEED."

1910.308(a)(5)(vii)

A means (for example, a fuseholder and fuse designed for the purpose) shall be provided

to completely isolate equipment for inspection and repairs. Isolating means that are not

designed to interrupt the load current of the circuit shall be either interlocked with an

approved circuit interrupter or provided with a sign warning against opening them under

load.

1910.308(a)(6)

Mobile and portable equipment.

1910.308(a)(6)(i)

A metallic enclosure shall be provided on the mobile machine for enclosing the terminals

of the power cable. The enclosure shall include provisions for a solid connection for the

grounding terminal to effectively ground the machine frame. The method of cable

termination used shall prevent any strain or pull on the cable from stressing the electrical

connections. The enclosure shall have provision for locking so only authorized qualified

persons may open it and shall be marked with a sign warning of the presence of

energized parts.

1910.308(a)(6)(ii)

All energized switching and control parts shall be enclosed in effectively grounded metal

cabinets or enclosures. Circuit breakers and protective equipment shall have the

operating means projecting through the metal cabinet or enclosure so these units can be

reset without locked doors being opened. Enclosures and metal cabinets shall be locked

so that only authorized qualified persons have access and shall be marked with a sign

warning of the presence of energized parts. Collector ring assemblies on revolving-type

machines (shovels, draglines, etc.) shall be guarded.

154

1910.308(a)(7)

Tunnel installations. This paragraph applies to installation and use of high-voltage power

distribution and utilization equipment that is portable or mobile, such as substations,

trailers, cars, mobile shovels, draglines, hoists, drills, dredges, compressors, pumps,

conveyors, and underground excavators.

1910.308(a)(7)(i)

Conductors in tunnels shall be installed in one or more of the following:

1910.308(a)(7)(i)(A)

Metal conduit or other metal raceway;

1910.308(a)(7)(i)(B)

Type MC cable; or

1910.308(a)(7)(i)(C)

Other approved multiconductor cable.

1910.308(a)(7)(ii)

Multiconductor portable cable may supply mobile equipment.

1910.308(a)(7)(iii)

Conductors and cables shall also be so located or guarded as to protect them from

physical damage. An equipment grounding conductor shall be run with circuit conductors

inside the metal raceway or inside the multiconductor cable jacket. The equipment

grounding conductor may be insulated or bare.

1910.308(a)(7)(iv)

Bare terminals of transformers, switches, motor controllers, and other equipment shall be

enclosed to prevent accidental contact with energized parts.

155

1910.308(a)(7)(v)

Enclosures for use in tunnels shall be drip-proof, weatherproof, or submersible as

required by the environmental conditions.

1910.308(a)(7)(vi)

Switch or contactor enclosures may not be used as junction boxes or raceways for

conductors feeding through or tapping off to other switches, unless special designs are

used to provide adequate space for this purpose.

1910.308(a)(7)(vii)

A disconnecting means that simultaneously opens all ungrounded conductors shall be

installed at each transformer or motor location.

1910.308(a)(7)(viii)

All nonenergized metal parts of electric equipment and metal raceways and cable sheaths

shall be effectively grounded and bonded to all metal pipes and rails at the portal and at

intervals not exceeding 305 m (1000 ft) throughout the tunnel.

1910.308(b)

Emergency power systems. This paragraph applies to circuits, systems, and equipment

intended to supply power for illumination and special loads in the event of failure of the

normal supply.

1910.308(b)(1)

Wiring methods. Emergency circuit wiring shall be kept entirely independent of all other

wiring and equipment and may not enter the same raceway, cable, box, or cabinet or

other wiring except either where common circuit elements suitable for the purpose are

required, or for transferring power from the normal to the emergency source.

1910.308(b)(2)

Emergency illumination. Emergency illumination shall include all required means of

egress lighting, illuminated exit signs, and all other lights necessary to provide

illumination. Where emergency lighting is necessary, the system shall be so arranged

156

that the failure of any individual lighting element, such as the burning out of a light bulb,

cannot leave any space in total darkness.

1910.308(b)(3)

Signs.

1910.308(b)(3)(i)

A sign shall be placed at the service entrance equipment indicating the type and location

of on-site emergency power sources. However, a sign is not required for individual unit

equipment.

1910.308(b)(3)(ii)

Where the grounded circuit conductor connected to the emergency source is connected to

a grounding electrode conductor at a location remote from the emergency source, there

shall be a sign at the grounding location that shall identify all emergency and normal

sources connected at that location.

1910.308(c)

Class 1, Class 2, and Class 3 remote control, signaling, and power-limited circuits --

1910.308(c)(1)

Classification. Class 1, Class 2, and Class 3 remote control, signaling, or power-limited

circuits are characterized by their usage and electrical power limitation that differentiates

them from light and power circuits. These circuits are classified in accordance with their

respective voltage and power limitations as summarized in paragraphs (c)(1)(i) through

(c)(1)(iii) of this section.

1910.308(c)(1)(i)

A Class 1 power-limited circuit shall be supplied from a source having a rated output of

not more than 30 volts and 1000 volt-amperes.

1910.308(c)(1)(ii)

A Class 1 remote control circuit or a Class 1 signaling circuit shall have a voltage not

exceeding 600 volts; however, the power output of the source need not be limited.

157

1910.308(c)(1)(iii)

The power source for a Class 2 or Class 3 circuit shall be listed equipment marked as a

Class 2 or Class 3 power source, except as follows:

1910.308(c)(1)(iii)(A)

Thermocouples do not require listing as a Class 2 power source; and

1910.308(c)(1)(iii)(B)

A dry cell battery is considered an inherently limited Class 2 power source, provided the

voltage is 30 volts or less and the capacity is less than or equal to that available from

series-connected No. 6 carbon zinc cells.

1910.308(c)(2)

Marking. A Class 2 or Class 3 power supply unit shall be durably marked where plainly

visible to indicate the class of supply and its electrical rating.

1910.308(c)(3)

Separation from conductors of other circuits. Cables and conductors of Class 2 and Class

3 circuits may not be placed in any cable, cable tray, compartment, enclosure, manhole,

outlet box, device box, raceway, or similar fitting with conductors of electric light, power,

Class 1, nonpower-limited fire alarm circuits, and medium power network-powered

broadband communications cables unless a barrier or other equivalent form of protection

against contact is employed.

1910.308(d)

Fire alarm systems --

1910.308(d)(1)

Classifications. Fire alarm circuits shall be classified either as nonpower limited or power

limited.

158

1910.308(d)(2)

Power sources. The power sources for use with fire alarm circuits shall be either power

limited or nonpower limited as follows:

1910.308(d)(2)(i)

The power source of nonpower-limited fire alarm (NPLFA) circuits shall have an output

voltage of not more than 600 volts, nominal; and

1910.308(d)(2)(ii)

The power source for a power-limited fire alarm (PLFA) circuit shall be listed equipment

marked as a PLFA power source.

1910.308(d)(3)

Separation from conductors of other circuits.

1910.308(d)(3)(i)

Nonpower-limited fire alarm circuits and Class 1 circuits may occupy the same enclosure,

cable, or raceway provided all conductors are insulated for maximum voltage of any

conductor within the enclosure, cable, or raceway. Power supply and fire alarm circuit

conductors are permitted in the same enclosure, cable, or raceway only if connected to

the same equipment.

1910.308(d)(3)(ii)

Power-limited circuit cables and conductors may not be placed in any cable, cable tray,

compartment, enclosure, outlet box, raceway, or similar fitting with conductors of electric

light, power, Class 1, nonpower-limited fire alarm circuit conductors, or medium power

network-powered broadband communications circuits.

1910.308(d)(3)(iii)

Power-limited fire alarm circuit conductors shall be separated at least 50.8 mm (2 in.)

from conductors of any electric light, power, Class 1, nonpower-limited fire alarm, or

medium power network-powered broadband communications circuits unless a special and

equally protective method of conductor separation is employed.

159

1910.308(d)(3)(iv)

Conductors of one or more Class 2 circuits are permitted within the same cable,

enclosure, or raceway with conductors of power-limited fire alarm circuits provided that

the insulation of Class 2 circuit conductors in the cable, enclosure, or raceway is at least

that needed for the power-limited fire alarm circuits.

1910.308(d)(4)

Identification. Fire alarm circuits shall be identified at terminal and junction locations in a

manner that will prevent unintentional interference with the signaling circuit during

testing and servicing. Power-limited fire alarm circuits shall be durably marked as such

where plainly visible at terminations.

1910.308(e)

Communications systems. This paragraph applies to central-station-connected and non-

central-station-connected telephone circuits, radio and television receiving and

transmitting equipment, including community antenna television and radio distribution

systems, telegraph, district messenger, and outside wiring for fire and burglar alarm, and

similar central station systems. These installations need not comply with the provisions of

§ 1910.303 through § 1910.308(d), except for § 1910.304(c)(1) and § 1910.307.

1910.308(e)(1)

Protective devices.

1910.308(e)(1)(i)

A listed primary protector shall be provided on each circuit run partly or entirely in aerial

wire or aerial cable not confined within a block.

1910.308(e)(1)(ii)

A listed primary protector shall be also provided on each aerial or underground circuit

when the location of the circuit within the block containing the building served allows the

circuit to be exposed to accidental contact with electric light or power conductors

operating at over 300 volts to ground.

160

1910.308(e)(1)(iii)

In addition, where there exists a lightning exposure, each interbuilding circuit on

premises shall be protected by a listed primary protector at each end of the interbuilding

circuit.

1910.308(e)(2)

Conductor location.

1910.308(e)(2)(i)

Lead-in or aerial-drop cables from a pole or other support, including the point of initial

attachment to a building or structure, shall be kept away from electric light, power, Class

1, or nonpower-limited fire alarm circuit conductors so as to avoid the possibility of

accidental contact.

1910.308(e)(2)(ii)

A separation of at least 1.83 m (6 ft) shall be maintained between communications wires

and cables on buildings and lightning conductors.

1910.308(e)(2)(iii)

Where communications wires and cables and electric light or power conductors are

supported by the same pole or run parallel to each other in-span, the following conditions

shall be met:

1910.308(e)(2)(iii)(A)

Where practicable, communication wires and cables on poles shall be located below the

electric light or power conductors; and

1910.308(e)(2)(iii)(B)

Communications wires and cables may not be attached to a crossarm that carries electric

light or power conductors.

161

1910.308(e)(2)(iv)

Indoor communications wires and cables shall be separated at least 50.8 mm (2 in.) from

conductors of any electric light, power, Class 1, nonpower-limited fire alarm, or medium

power network-powered broadband communications circuits, unless a special and equally

protective method of conductor separation, identified for the purpose, is employed.

1910.308(e)(3)

Equipment location. Outdoor metal structures supporting antennas, as well as self-

supporting antennas such as vertical rods or dipole structures, shall be located as far

away from overhead conductors of electric light and power circuits of over 150 volts to

ground as necessary to prevent the antenna or structure from falling into or making

accidental contact with such circuits.

1910.308(e)(4)

Grounding.

1910.308(e)(4)(i)

If exposed to contact with electric light and power conductors, the metal sheath of aerial

cables entering buildings shall be grounded or shall be interrupted close to the entrance

to the building by an insulating joint or equivalent device. Where protective devices are

used, they shall be grounded in an approved manner.

1910.308(e)(4)(ii)

Masts and metal structures supporting antennas shall be permanently and effectively

grounded without splice or connection in the grounding conductor.

1910.308(e)(4)(iii)

Transmitters shall be enclosed in a metal frame or grill or separated from the operating

space by a barrier, all metallic parts of which are effectively connected to ground. All

external metal handles and controls accessible to the operating personnel shall be

effectively grounded. Unpowered equipment and enclosures are considered to be

grounded where connected to an attached coaxial cable with an effectively grounded

metallic shield.

162

1910.308(f)

Solar photovoltaic systems. This paragraph covers solar photovoltaic systems that can be

interactive with other electric power production sources or can stand alone with or

without electrical energy storage such as batteries. These systems may have ac or dc

output for utilization.

1910.308(f)(1)

Conductors of different systems. Photovoltaic source circuits and photovoltaic output

circuits may not be contained in the same raceway, cable tray, cable, outlet box, junction

box, or similar fitting as feeders or branch circuits of other systems, unless the

conductors of the different systems are separated by a partition or are connected

together.

1910.308(f)(2)

Disconnecting means. Means shall be provided to disconnect all current-carrying

conductors of a photovoltaic power source from all other conductors in a building or other

structure. Where a circuit grounding connection is not designed to be automatically

interrupted as part of the ground-fault protection system, a switch or circuit breaker used

as disconnecting means may not have a pole in the grounded conductor.

1910.308(g)

Integrated electrical systems --

1910.308(g)(1)

Scope. Paragraph (g) of this section covers integrated electrical systems, other than unit

equipment, in which orderly shutdown is necessary to ensure safe operation. An

integrated electrical system as used in this section shall be a unitized segment of an

industrial wiring system where all of the following conditions are met:

1910.308(g)(1)(i)

An orderly shutdown process minimizes employee hazard and equipment damage;

163

1910.308(g)(1)(ii)

The conditions of maintenance and supervision ensure that only qualified persons will

service the system; and

1910.308(g)(1)(ii)

The conditions of maintenance and supervision ensure that only qualified persons will

service the system; and

1910.308(g)(1)(iii)

Effective safeguards are established and maintained.

1910.308(g)(2)

Location of overcurrent devices in or on premises. Overcurrent devices that are critical to

integrated electrical systems need not be readily accessible to employees as required by

§ 1910.304(f)(1)(iv) if they are located with mounting heights to ensure security from

operation by nonqualified persons.


164


Scope - 1910.331



• Subpart: S



• Title: Scope

1910.331(a)

Covered work by both qualified and unqualified persons. The provisions of 1910.331

through 1910.335 cover electrical safety work practices for both qualified persons (those

who have training in avoiding the electrical hazards of working on or near exposed

energized parts) and unqualified persons (those with little or no such training) working

on, near, or with the following installations:

1910.331(a)(1)

Premises wiring. Installations of electric conductors and equipment within or on

buildings or other structures, and on other premises such as yards, carnival, parking, and

other lots, and industrial substations;

1910.331(a)(2)

Wiring for connection to supply. Installations of conductors that connect to the supply of

electricity; and

1910.331(a)(3)

Other wiring. Installations of other outside conductors on the premises.

1910.331(a)(4)

Optical fiber cable. Installations of optical fiber cable where such installations are made

along with electric conductors.

Note: See 1910.399 for the definition of "qualified person." See 1910.332 for training

requirements that apply to qualified and unqualified persons.

165

1910.331(b)

Other covered work by unqualified persons. The provisions of 1910.331 through

1910.335 also cover work performed by unqualified persons on, near, or with the

installations listed in paragraphs (c)(1) through (c)(4) of this section.

1910.331(c)

Excluded work by qualified persons. The provisions of 1910.331 through 1910.335 do

not apply to work performed by qualified persons on or directly associated with the

following installations:

1910.331(c)(1)

Generation, transmission, and distribution of electric energy (including communication

and metering) located in buildings used for such purposes or located outdoors.

Note 1: Work on or directly associated with installations of utilization equipment used for

purposes other than generating, transmitting, or distributing electric energy (such as

installations which are in office buildings, warehouses, garages, machine shops, or

recreational buildings, or other utilization installations which are not an integral part of a

generating installation, substation, or control center) is covered under paragraph (a)(1) of

this section.

Note 2: For work on or directly associated with utilization installations, an employer who

complies with the work practices of 1910.269 (electric power generation, transmission,

and distribution) will be deemed to be in compliance with 1910.333(c) and 1910.335.

However, the requirements of 1910.332, 1910.333(a), 1910.333(b), and 1910.334 apply

to all work on or directly associated with utilization installations, regardless of whether

the work is performed by qualified or unqualified persons.

Note 3: Work on or directly associated with generation, transmission, or distribution

installations includes:

{1} Work performed directly on such installations, such as repairing overhead or

underground distribution lines or repairing a feed-water pump for the boiler in a

generating plant.

{2} Work directly associated with such installations, such as line-clearance tree trimming

and replacing utility poles.

{3} Work on electric utilization circuits in a generating plant provided that:

{A} Such circuits are commingled with installations of power generation equipment or

circuits, and

166

{B} The generation equipment or circuits present greater electrical hazards than those

posed by the utilization equipment or circuits (such as exposure to higher voltages or lack

of overcurrent protection).

This work is covered by 1910.269 of this Part.

1910.331(c)(2)

Communications installations. Installations of communication equipment to the extent

that the work is covered under 1910.268.

1910.331(c)(3)

Installations in vehicles. Installations in ships, watercraft, railway rolling stock, aircraft or

automotive vehicles other than mobile homes and recreational vehicles.

1910.331(c)(4)

Railway installations. Installations of railways for generation, transformation,

transmission, or distribution of power used exclusively for operation of rolling stock or

installations of railways used exclusively for signaling and communication purposes.

[55 FR 32016, Aug. 6, 1990; 59 FR 4476, Jan. 31, 1994]

167

168


Training - 1910.332



• Subpart: S



• Title: Training

1910.332(a)

Scope. The training requirements contained in this section apply to employees who face a

risk of electric shock that is not reduced to a safe level by the electrical installation

requirements of 1910.303 through 1910.308.

Note: Employees in occupations listed in Table S-4 face such a risk and are required to be

trained. Other employees who also may reasonably be expected to face comparable risk

of injury due to electric shock or other electrical hazards must also be trained.

1910.332(b)

Content of training.

1910.332(b)(1)

Practices addressed in this standard. Employees shall be trained in and familiar with the

safety-related work practices required by 1910.331 through 1910.335 that pertain to

their respective job assignments.

1910.332(b)(2)

Additional requirements for unqualified persons. Employees who are covered by

paragraph (a) of this section but who are not qualified persons shall also be trained in

and familiar with any electrically related safety practices not specifically addressed by

1910.331 through 1910.335 but which are necessary for their safety.

169

1910.332(b)(3)

Additional requirements for qualified persons. Qualified persons (i.e. those permitted to

work on or near exposed energized parts) shall, at a minimum, be trained in and familiar

with the following:

1910.332(b)(3)(i)

The skills and techniques necessary to distinguish exposed live parts from other parts of

electric equipment.

1910.332(b)(3)(ii)

The skills and techniques necessary to determine the nominal voltage of exposed live

parts, and

1910.332(b)(3)(iii)

The clearance distances specified in 1910.333(c) and the corresponding voltages to which

the qualified person will be exposed.

Note 1: For the purposes of 1910.331 through 1910.335, a person must have the training

required by paragraph (b)(3) of this section in order to be considered a qualified person.

Note 2: Qualified persons whose work on energized equipment involves either direct

contact or contact by means of tools or materials must also have the training needed to

meet 1910.333(C)(2).

1910.332(c)

Type of training. The training required by this section shall be of the classroom or on-the-

job type. The degree of training provided shall be determined by the risk to the

employee.

170

TABLE S-4. -- Typical Occupational Categories of Employees

Facing a Higher Than Normal Risk of Electrical Accident

_______________________________________________________________________

__

Occupation

_______________________________________________________________________

__

Blue collar supervisors(1)

Electrical and electronic engineers(1)

Electrical and electronic equipment assemblers(1)

Electrical and electronic technicians(1)

Electricians

Industrial machine operators(1)

Material handling equipment operators(1)

Mechanics and repairers(1)

Painters(1)

Riggers and roustabouts(1)

Stationary engineers(1)

Welders

_______________________________________________________________________

__

Footnote(1) Workers in these groups do not need to be trained if their

work or the work of those they supervise does not bring them or the

employees they supervise close enough to exposed parts of electric

circuits

operating at 50 volts or more to ground for a hazard to exist.

[55 FR 32016, Aug. 6, 1990]

171

172


Selection and use of work practices - 1910.333



• Subpart: S



• Title: Selection and use of work practices

1910.333(a)

"General." Safety-related work practices shall be employed to prevent electric shock or

other injuries resulting from either direct or indirect electrical contacts, when work is

performed near or on equipment or circuits which are or may be energized. The specific

safety-related work practices shall be consistent with the nature and extent of the

associated electrical hazards.

1910.333(a)(1)

"Deenergized parts." Live parts to which an employee may be exposed shall be

deenergized before the employee works on or near them, unless the employer can

demonstrate that deenergizing introduces additional or increased hazards or is infeasible

due to equipment design or operational limitations. Live parts that operate at less than 50

volts to ground need not be deenergized if there will be no increased exposure to

electrical burns or to explosion due to electric arcs.

Note 1: Examples of increased or additional hazards include interruption of life support

equipment, deactivation of emergency alarm systems, shutdown of hazardous location

ventilation equipment, or removal of illumination for an area.

173

Note 2: Examples of work that may be performed on or near energized circuit parts

because of infeasibility due to equipment design or operational limitations include testing

of electric circuits that can only be performed with the circuit energized and work on

circuits that form an integral part of a continuous industrial process in a chemical plant

that would otherwise need to be completely shut down in order to permit work on one

circuit or piece of equipment.

Note 3: Work on or near deenergized parts is covered by paragraph (b) of this section.

1910.333(a)(2)

"Energized parts." If the exposed live parts are not deenergized (i.e., for reasons of

increased or additional hazards or infeasibility), other safety-related work practices shall

be used to protect employees who may be exposed to the electrical hazards involved.

Such work practices shall protect employees against contact with energized circuit parts

directly with any part of their body or indirectly through some other conductive object.

The work practices that are used shall be suitable for the conditions under which the work

is to be performed and for the voltage level of the exposed electric conductors or circuit

parts. Specific work practice requirements are detailed in paragraph (c) of this section.

1910.333(b)

"Working on or near exposed deenergized parts."

1910.333(b)(1)

"Application." This paragraph applies to work on exposed deenergized parts or near

enough to them to expose the employee to any electrical hazard they present. Conductors

and parts of electric equipment that have been deenergized but have not been locked out

or tagged in accordance with paragraph (b) of this section shall be treated as energized

parts, and paragraph (c) of this section applies to work on or near them.

174

1910.333(b)(2)

"Lockout and Tagging." While any employee is exposed to contact with parts of fixed

electric equipment or circuits which have been deenergized, the circuits energizing the

parts shall be locked out or tagged or both in accordance with the requirements of this

paragraph. The requirements shall be followed in the order in which they are presented

(i.e., paragraph (b)(2)(i) first, then paragraph (b)(2)(ii), etc.).

Note 1: As used in this section, fixed equipment refers to equipment fastened in place or

connected by permanent wiring methods.

Note 2: Lockout and tagging procedures that comply with paragraphs (c) through (f) of

1910.147 will also be deemed to comply with paragraph (b)(2) of this section provided

that:

[1] The procedures address the electrical safety hazards covered by this Subpart; and

[2] The procedures also incorporate the requirements of paragraphs (b)(2)(iii)(D) and

(b)(2)(iv)(B) of this section.

1910.333(b)(2)(i)

"Procedures." The employer shall maintain a written copy of the procedures outlined in

paragraph (b)(2) and shall make it available for inspection by employees and by the

Assistant Secretary of Labor and his or her authorized representatives.

Note: The written procedures may be in the form of a copy of paragraph (b) of this

section.

1910.333(b)(2)(ii)

"Deenergizing equipment."

1910.333(b)(2)(ii)(A)

175

Safe procedures for deenergizing circuits and equipment shall be determined before

circuits or equipment are deenergized.

1910.333(b)(2)(ii)(B)

The circuits and equipment to be worked on shall be disconnected from all electric

energy sources. Control circuit devices, such as push buttons, selector switches, and

interlocks, may not be used as the sole means for deenergizing circuits or equipment.

Interlocks for electric equipment may not be used as a substitute for lockout and tagging

procedures.

1910.333(b)(2)(ii)(C)

Stored electric energy which might endanger personnel shall be released. Capacitors shall

be discharged and high capacitance elements shall be short-circuited and grounded, if the

stored electric energy might endanger personnel.

Note: If the capacitors or associated equipment are handled in meeting this requirement,

they shall be treated as energized.

1910.333(b)(2)(ii)(D)

Stored non-electrical energy in devices that could reenergize electric circuit parts shall be

blocked or relieved to the extent that the circuit parts could not be accidentally energized

by the device.

1910.333(b)(2)(iii)

"Application of locks and tags."

1910.333(b)(2)(iii)(A)

A lock and a tag shall be placed on each disconnecting means used to deenergize circuits

and equipment on which work is to be performed, except as provided in paragraphs

(b)(2)(iii)(C) and (b)(2)(iii)(E) of this section. The lock shall be attached so as to prevent

176

persons from operating the disconnecting means unless they resort to undue force or the

use of tools.

1910.333(b)(2)(iii)(B)

Each tag shall contain a statement prohibiting unauthorized operation of the

disconnecting means and removal of the tag.

1910.333(b)(2)(iii)(C)

If a lock cannot be applied, or if the employer can demonstrate that tagging procedures

will provide a level of safety equivalent to that obtained by the use of a lock, a tag may be

used without a lock.

1910.333(b)(2)(iii)(D)

A tag used without a lock, as permitted by paragraph (b)(2)(iii)(C) of this section, shall

be supplemented by at least one additional safety measure that provides a level of safety

equivalent to that obtained by use of a lock. Examples of additional safety measures

include the removal of an isolating circuit element, blocking of a controlling switch, or

opening of an extra disconnecting device.

1910.333(b)(2)(iii)(E)

A lock may be placed without a tag only under the following conditions:

1910.333(b)(2)(iii)(E)(1)

Only one circuit or piece of equipment is deenergized, and

1910.333(b)(2)(iii)(E)(2)

The lockout period does not extend beyond the work shift, and

1910.333(b)(2)(iii)(E)(3)

177

Employees exposed to the hazards associated with reenergizing the circuit or equipment

are familiar with this procedure.

1910.333(b)(2)(iv)

Verification of deenergized condition. The requirements of this paragraph shall be met

before any circuits or equipment can be considered and worked as deenergized.

1910.333(b)(2)(iv)(A)

A qualified person shall operate the equipment operating controls or otherwise verify that

the equipment cannot be restarted.

1910.333(b)(2)(iv)(B)

A qualified person shall use test equipment to test the circuit elements and electrical parts

of equipment to which employees will be exposed and shall verify that the circuit

elements and equipment parts are deenergized. The test shall also determine if any

energized condition exists as a result of inadvertently induced voltage or unrelated

voltage backfeed even though specific parts of the circuit have been deenergized and

presumed to be safe. If the circuit to be tested is over 600 volts, nominal, the test

equipment shall be checked for proper operation immediately after this test.

1910.333(b)(2)(v)

"Reenergizing equipment." These requirements shall be met, in the order given, before

circuits or equipment are reenergized, even temporarily.

1910.333(b)(2)(v)(A)

A qualified person shall conduct tests and visual inspections, as necessary, to verify that

all tools, electrical jumpers, shorts, grounds, and other such devices have been removed,

so that the circuits and equipment can be safely energized.

178

1910.333(b)(2)(v)(B)

Employees exposed to the hazards associated with reenergizing the circuit or equipment

shall be warned to stay clear of circuits and equipment.

1910.333(b)(2)(v)(C)

Each lock and tag shall be removed by the employee who applied it or under his or her

direct supervision. However, if this employee is absent from the workplace, then the lock

or tag may be removed by a qualified person designated to perform this task provided

that:

1910.333(b)(2)(v)(C)(1)

The employer ensures that the employee who applied the lock or tag is not available at

the workplace, and

1910.333(b)(2)(v)(C)(2)

The employer ensures that the employee is aware that the lock or tag has been removed

before he or she resumes work at that workplace.

1910.333(b)(2)(v)(D)

There shall be a visual determination that all employees are clear of the circuits and

equipment.

1910.333(c)

"Working on or near exposed energized parts."

1910.333(c)(1)

"Application." This paragraph applies to work performed on exposed live parts

(involving either direct contact or by means of tools or materials) or near enough to them

for employees to be exposed to any hazard they present.

179

1910.333(c)(2)

"Work on energized equipment." Only qualified persons may work on electric circuit

parts or equipment that have not been deenergized under the procedures of paragraph (b)

of this section. Such persons shall be capable of working safely on energized circuits and

shall be familiar with the proper use of special precautionary techniques, personal

protective equipment, insulating and shielding materials, and insulated tools.

1910.333(c)(3)

"Overhead lines." if work is to be performed near overhead lines, the lines shall be

deenergized and grounded, or other protective measures shall be provided before work is

started. If the lines are to be deenergized, arrangements shall be made with the person or

organization that operates or controls the electric circuits involved to deenergize and

ground them. If protective measures, such as guarding, isolating, or insulating, are

provided, these precautions shall prevent employees from contacting such lines directly

with any part of their body or indirectly through conductive materials, tools, or

equipment.

Note: The work practices used by qualified persons installing insulating devices on

overhead power transmission or distribution lines are covered by 1910.269 of this Part,

not by 1910.332 through 1910.335 of this Part. Under paragraph (c)(2) of this section,

unqualified persons are prohibited from performing this type of work.

1910.333(c)(3)(i)

"Unqualified persons."

1910.333(c)(3)(i)(A)

When an unqualified person is working in an elevated position near overhead lines, the

location shall be such that the person and the longest conductive object he or she may

contact cannot come closer to any unguarded, energized overhead line than the following

distances:

180

1910.333(c)(3)(i)(A)(1)

For voltages to ground 50kV or below - 10 feet (305 cm);

1910.333(c)(3)(i)(A)(2)

For voltages to ground over 50kV - 10 feet (305 cm) plus 4 inches (10 cm) for every

10kV over 50kV.

1910.333(c)(3)(i)(B)

When an unqualified person is working on the ground in the vicinity of overhead lines,

the person may not bring any conductive object closer to unguarded, energized overhead

lines than the distances given in paragraph (c)(3)(i)(A) of this section.

Note: For voltages normally encountered with overhead power line, objects which do not

have an insulating rating for the voltage involved are considered to be conductive.

1910.333(c)(3)(ii)

"Qualified persons." When a qualified person is working in the vicinity of overhead lines,

whether in an elevated position or on the ground, the person may not approach or take

any conductive object without an approved insulating handle closer to exposed energized

parts than shown in Table S-5 unless:

1910.333(c)(3)(ii)(A)

The person is insulated from the energized part (gloves, with sleeves if necessary, rated

for the voltage involved are considered to be insulation of the person from the energized

part on which work is performed), or

1910.333(c)(3)(ii)(B)

The energized part is insulated both from all other conductive objects at a different

potential and from the person, or

181

1910.333(c)(3)(ii)(C)

The person is insulated from all conductive objects at a potential different from that of

the energized part.

TABLE S-5 - APPROACH DISTANCES FOR QUALIFIED

EMPLOYEES - ALTERNATING CURRENT

______________________________________________________________

|

Voltage range (phase to phase) | Minimum approach distance

__________________________________|___________________________

|

300V and less ....................| Avoid Contact

Over 300V, not over 750V .........| 1 ft. 0 in. (30.5 cm).

Over 750V, not over 2kV ..........| 1 ft. 6 in. (46 cm).

Over 2kV, not over 15kV ..........| 2 ft. 0 in. (61 cm).

Over 15kV, not over 37kV .........| 3 ft. 0 in. (91 cm).

Over 37kV, not over 87.5kV .......| 3 ft. 6 in. (107 cm).

Over 87.5kV, not over 121kV ......| 4 ft. 0 in. (122 cm).

Over 121kV, not over 140kV .......| 4 ft. 6 in. (137 cm).

__________________________________|___________________________

1910.333(c)(3)(iii)

"Vehicular and mechanical equipment."

1910.333(c)(3)(iii)(A)

Any vehicle or mechanical equipment capable of having parts of its structure elevated

near energized overhead lines shall be operated so that a clearance of 10 ft. (305 cm) is

maintained. If the voltage is higher than 50kV, the clearance shall be increased 4 in. (10

cm) for every 10kV over that voltage. However, under any of the following conditions,

the clearance may be reduced:

182

1910.333(c)(3)(iii)(A)(1)

If the vehicle is in transit with its structure lowered, the clearance may be reduced to 4 ft.

(122 cm). If the voltage is higher than 50kV, the clearance shall be increased 4 in. (10

cm) for every 10 kV over that voltage.

1910.333(c)(3)(iii)(A)(2)

If insulating barriers are installed to prevent contact with the lines, and if the barriers are

rated for the voltage of the line being guarded and are not a part of or an attachment to

the the vehicle or its raised structure, the clearance may be reduced to a distance within

the designed working dimensions of the insulating barrier.

1910.333(c)(3)(iii)(A)(3)

If the equipment is an aerial lift insulated for the voltage involved, and if the work is

performed by a qualified person, the clearance (between the uninsulated portion of the

aerial lift and the power line) may be reduced to the distance given in Table S-5.

1910.333(c)(3)(iii)(B)

Employees standing on the ground may not contact the vehicle or mechanical equipment

or any of its attachments, unless:

1910.333(c)(3)(iii)(B)(1)

The employee is using protective equipment rated for the voltage; or

1910.333(c)(3)(iii)(B)(2)

The equipment is located so that no uninsulated part of its structure (that portion of the

structure that provides a conductive path to employees on the ground) can come closer to

the line than permitted in paragraph (c)(3)(iii) of this section.

183

1910.333(c)(3)(iii)(C)

If any vehicle or mechanical equipment capable of having parts of its structure elevated

near energized overhead lines is intentionally grounded, employees working on the

ground near the point of grounding may not stand at the grounding location whenever

there is a possibility of overhead line contact. Additional precautions, such as the use of

barricades or insulation, shall be taken to protect employees from hazardous ground

potentials, depending on earth resistivity and fault currents, which can develop within the

first few feet or more outward from the grounding point.

1910.333(c)(4)

"Illumination."

1910.333(c)(4)(i)

Employees may not enter spaces containing exposed energized parts, unless illumination

is provided that enables the employees to perform the work safely.

1910.333(c)(4)(ii)

Where lack of illumination or an obstruction precludes observation of the work to be

performed, employees may not perform tasks near exposed energized parts. Employees

may not reach blindly into areas which may contain energized parts.

1910.333(c)(5)

"Confined or enclosed work spaces." When an employee works in a confined or enclosed

space (such as a manhole or vault) that contains exposed energized parts, the employer

shall provide, and the employee shall use, protective shields, protective barriers, or

insulating materials as necessary to avoid inadvertent contact with these parts. Doors,

hinged panels, and the like shall be secured to prevent their swinging into an employee

and causing the employee to contact exposed energized parts.

184

1910.333(c)(6)

"Conductive materials and equipment." Conductive materials and equipment that are in

contact with any part of an employee's body shall be handled in a manner that will

prevent them from contacting exposed energized conductors or circuit parts. If an

employee must handle long dimensional conductive objects (such as ducts and pipes) in

areas with exposed live parts, the employer shall institute work practices (such as the use

of insulation, guarding, and material handling techniques) which will minimize the

hazard.

1910.333(c)(7)

"Portable ladders." Portable ladders shall have nonconductive siderails if they are used

where the employee or the ladder could contact exposed energized parts.

1910.333(c)(8)

"Conductive apparel." Conductive articles of jewelry and clothing (such a watch bands,

bracelets, rings, key chains, necklaces, metalized aprons, cloth with conductive thread, or

metal headgear) may not be worn if they might contact exposed energized parts.

However, such articles may be worn if they are rendered nonconductive by covering,

wrapping, or other insulating means.

1910.333(c)(9)

"Housekeeping duties." Where live parts present an electrical contact hazard, employees

may not perform housekeeping duties at such close distances to the parts that there is a

possibility of contact, unless adequate safeguards (such as insulating equipment or

barriers) are provided. Electrically conductive cleaning materials (including conductive

solids such as steel wool, metalized cloth, and silicon carbide, as well as conductive

liquid solutions) may not be used in proximity to energized parts unless procedures are

followed which will prevent electrical contact.

185

1910.333(c)(10)

"Interlocks." Only a qualified person following the requirements of paragraph (c) of this

section may defeat an electrical safety interlock, and then only temporarily while he or

she is working on the equipment. The interlock system shall be returned to its operable

condition when this work is completed.

[55 FR 32016, Aug. 6, 1990; 55 FR 42053, Nov. 1, 1990; as amended at 59 FR 4476, Jan.

31, 1994]

186


Use of equipment. - 1910.334



• Subpart: S



• Title: Use of equipment.

1910.334(a)

"Portable electric equipment." This paragraph applies to the use of cord and plug

connected equipment, including flexible cord sets (extension cords).

1910.334(a)(1)

"Handling." Portable equipment shall be handled in a manner which will not cause

damage. Flexible electric cords connected to equipment may not be used for raising or

lowering the equipment. Flexible cords may not be fastened with staples or otherwise

hung in such a fashion as could damage the outer jacket or insulation.

1910.334(a)(2)

"Visual inspection."

1910.334(a)(2)(i)

Portable cord and plug connected equipment and flexible cord sets (extension cords) shall

be visually inspected before use on any shift for external defects (such as loose parts,

deformed and missing pins, or damage to outer jacket or insulation) and for evidence of

possible internal damage (such as pinched or crushed outer jacket). Cord and plug

connected equipment and flexible cord sets (extension cords) which remain connected

187

once they are put in place and are not exposed to damage need not be visually inspected

until they are relocated.

1910.334(a)(2)(ii)

If there is a defect or evidence of damage that might expose an employee to injury, the

defective or damaged item shall be removed from service, and no employee may use it

until repairs and tests necessary to render the equipment safe have been made.

1910.334(a)(2)(iii)

When an attachment plug is to be connected to a receptacle (including an on a cord set),

the relationship of the plug and receptacle contacts shall first be checked to ensure that

they are of proper mating configurations.

1910.334(a)(3)

"Grounding type equipment."

1910.334(a)(3)(i)

A flexible cord used with grounding type equipment shall contain an equipment

grounding conductor.

1910.334(a)(3)(ii)

Attachment plugs and receptacles may not be connected or altered in a manner which

would prevent proper continuity of the equipment grounding conductor at the point where

plugs are attached to receptacles. Additionally, these devices may not be altered to allow

the grounding pole of a plug to be inserted into slots intended for connection to the

current-carrying conductors.

1910.334(a)(3)(iii)

Adapters which interrupt the continuity of the equipment grounding connection may not

be used.

188

1910.334(a)(4)

"Conductive work locations." Portable electric equipment and flexible cords used in

highly conductive work locations (such a those inundated with water or other conductive

liquids), or in job locations where employees are likely to contact water or conductive

liquids,shall be approved for those locations.

1910.334(a)(5)

"Connecting attachment plugs."

1910.334(a)(5)(i)

Employees' hands may not be wet when plugging and unplugging flexible cords and cord

and plug connected equipment, if energized equipment is involved.

1910.334(a)(5)(ii)

Energized plug and receptacle connections may be handled only with insulating

protective equipment if the condition of the connection could provide a conducting path

to the employee's hand (if, for example, a cord connector is wet from being immersed in

water).

1910.334(a)(5)(iii)

Locking type connectors shall be properly secured after connection.

1910.334(b)

"Electric power and lighting circuits."

1910.334(b)(1)

"Routine opening and closing of circuits." Load rated switches, circuit breakers, or other

devices specifically designed as disconnecting means shall be used for the opening,

reversing, or closing of circuits under load conditions. Cable connectors not of the load

189

break type, fuses, terminal lugs, and cable splice connections may not be used for such

purposes, except in an emergency.

1910.334(b)(2)

"Reclosing circuits after protective device operation." After a circuit is deenergized by a

circuit protective device, the circuit protective device, the circuit may not be manually

reenergized until it has been determined that the equipment and circuit can be safely

energized. The repetitive manual reclosing of circuit breakers or reenergizing circuits

through replaced fuses is prohibited.

Note: When it can be determined from the design of the circuit and the overcurrent

devices involved that the automatic operation of a device was caused by an overload

rather than a fault condition, no examination of the circuit or connected equipment is

needed before the circuit is reenergized.

1910.334(b)(3)

"Overcurrent protection modification." Overcurrent protection of circuits and conductors

may not be modified, even on a temporary basis, beyond that allowed by 1910.304(e), the

installation safety requirements for overcurrent protection.

1910.334(c)

"Test instruments and equipment."

1910.334(c)(1)

"Use." Only qualified persons may perform testing work on electric circuits or

equipment.

1910.334(c)(2)

"Visual inspection." Test instruments and equipment and all associated test leads, cables,

power cords, probes, and connectors shall be visually inspected for external defects and

damage before the equipment is used. If there is a defect or evidence of damage that

190

might expose an employee to injury, the defective or damaged item shall be removed

from service, and no employee may use it until repairs and tests necessary to render the

equipment safe have been made.

1910.334(c)(3)

"Rating of equipment." Test instruments and equipment and their accessories shall be

rated for the circuits and equipment to which they will be connected and shall be

designed for the environment in which they will be used.

1910.334(d)

"Occasional use of flammable or ignitable materials." Where flammable materials are

present only occasionally, electric equipment capable of igniting them shall not be used,

unless measures are taken to prevent hazardous conditions from developing. Such

materials include, but are not limited to: flammable gases, vapors, or liquids; combustible

dust; and ignitable fibers or flyings.

Note: Electrical installation requirements for locations where flammable materials are

present on a regular basis are contained in 1910.307.

[55 FR 32016, Aug. 6, 1990; 55 FR 46054, Nov. 1, 1990]

191

192


Safeguards for personnel protection. - 1910.335



• Subpart: S



• Title: Safeguards for personnel protection.

1910.335(a)

Use of protective equipment.

1910.335(a)(1)

Personal protective equipment.

1910.335(a)(1)(i)

Employees working in areas where there are potential electrical hazards shall be provided

with, and shall use, electrical protective equipment that is appropriate for the specific

parts of the body to be protected and for the work to be performed.

Note: Personal protective equipment requirements are contained in subpart I of this part.

1910.335(a)(1)(ii)

Protective equipment shall be maintained in a safe, reliable condition and shall be

periodically inspected or tested, as required by 1910.137.

193

1910.335(a)(1)(iii)

If the insulating capability of protective equipment may be subject to damage during use,

the insulating material shall be protected. (For example, an outer covering of leather is

sometimes used for the protection of rubber insulating material.)

1910.335(a)(1)(iv)

Employees shall wear nonconductive head protection wherever there is a danger of head

injury from electric shock or burns due to contact with exposed energized parts.

1910.335(a)(1)(v)

Employees shall wear protective equipment for the eyes or face wherever there is danger

of injury to the eyes or face from electric arcs or flashes or from flying objects resulting

from electrical explosion.

1910.335(a)(2)

General protective equipment and tools.

1910.335(a)(2)(i)

When working near exposed energized conductors or circuit parts, each employee shall

use insulated tools or handling equipment if the tools or handling equipment might make

contact with such conductors or parts. If the insulating capability of insulated tools or

handling equipment is subject to damage, the insulating material shall be protected.

1910.335(a)(2)(i)(A)

Fuse handling equipment, insulated for the circuit voltage, shall be used to remove or

install fuses when the fuse terminals are energized.

1910.335(a)(2)(i)(B)

Ropes and handlines used near exposed energized parts shall be nonconductive.

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1910.335(a)(2)(ii)

Protective shields, protective barriers, or insulating materials shall be used to protect each

employee from shock, burns, or other electrically related injuries while that employee is

working near exposed energized parts which might be accidentally contacted or where

dangerous electric heating or arcing might occur. When normally enclosed live parts are

exposed for maintenance or repair, they shall be guarded to protect unqualified persons

from contact with the live parts.

1910.335(b)

Alerting techniques. The following alerting techniques. The following alerting techniques

shall be used to warn and protect employees from hazards which could cause injury due

to electric shock, burns, or failure of electric equipment parts:

1910.335(b)(1)

Safety signs and tags. Safety signs, safety symbols, or accident prevention tags shall be

used where necessary to warn employees about electrical hazards which may endanger

them, as required by 1910.145.

1910.335(b)(2)

Barricades. Barricades shall be used in conjunction with safety signs where it is necessary

to prevent or limit employee access to work areas exposing employees to uninsulated

energized conductors or circuit parts. Conductive barricades may not be used where they

might cause an electrical contact hazard.

1910.335(b)(3)

Attendants. If signs and barricades do not provide sufficient warning and protection from

electrical hazards, an attendant shall be stationed to warn and protect employees.

[55 FR 32016, Aug. 6, 1990]

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196


Definitions applicable to this subpart. - 1910.399



• Subpart: S



• Title: Definitions applicable to this subpart.

Acceptable. An installation or equipment is acceptable to the Assistant Secretary of Labor,

and approved within the meaning of this Subpart S:

(1) If it is accepted, or certified, or listed, or labeled, or otherwise determined to be safe

by a nationally recognized testing laboratory recognized pursuant to § 1910.7; or

(2) With respect to an installation or equipment of a kind that no nationally recognized

testing laboratory accepts, certifies, lists, labels, or determines to be safe, if it is

inspected or tested by another Federal agency, or by a State, municipal, or other local

authority responsible for enforcing occupational safety provisions of the National Electrical

Code, and found in compliance with the provisions of the National Electrical Code as

applied in this subpart; or

(3) With respect to custom-made equipment or related installations that are designed,

fabricated for, and intended for use by a particular customer, if it is determined to be

safe for its intended use by its manufacturer on the basis of test data which the employer

keeps and makes available for inspection to the Assistant Secretary and his authorized

representatives.

Accepted. An installation is "accepted" if it has been inspected and found by a nationally

recognized testing laboratory to conform to specified plans or to procedures of applicable

codes.

Accessible. (As applied to wiring methods.) Capable of being removed or exposed without

damaging the building structure or finish, or not permanently closed in by the structure

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or finish of the building. (See "concealed" and "exposed.")

Accessible. (As applied to equipment.) Admitting close approach; not guarded by locked

doors, elevation, or other effective means. (See "Readily accessible.")

Ampacity. The current, in amperes, that a conductor can carry continuously under the

conditions of use without exceeding its temperature rating.

Appliances. Utilization equipment, generally other than industrial, normally built in

standardized sizes or types, that is installed or connected as a unit to perform one or

more functions.

Approved. Acceptable to the authority enforcing this subpart. The authority enforcing this

subpart is the Assistant Secretary of Labor for Occupational Safety and Health. The

definition of "acceptable" indicates what is acceptable to the Assistant Secretary of Labor,

and therefore approved within the meaning of this subpart.

Armored cable (Type AC). A fabricated assembly of insulated conductors in a flexible

metallic enclosure.

Askarel. A generic term for a group of nonflammable synthetic chlorinated hydrocarbons

used as electrical insulating media. Askarels of various compositional types are used.

Under arcing conditions, the gases produced, while consisting predominantly of

noncombustible hydrogen chloride, can include varying amounts of combustible gases

depending upon the askarel type.

Attachment plug (Plug cap)(Cap). A device that, by insertion in a receptacle, establishes

a connection between the conductors of the attached flexible cord and the conductors

connected permanently to the receptacle.

Automatic. Self-acting, operating by its own mechanism when actuated by some

impersonal influence, as, for example, a change in current strength, pressure,

temperature, or mechanical configuration.

Bare conductor. See Conductor.

Barrier. A physical obstruction that is intended to prevent contact with equipment or live

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parts or to prevent unauthorized access to a work area.

Bathroom. An area including a basin with one or more of the following: a toilet, a tub, or

a shower.

Bonding (Bonded). The permanent joining of metallic parts to form an electrically

conductive path that ensures electrical continuity and the capacity to conduct safely any

current likely to be imposed.

Bonding jumper. A conductor that assures the necessary electrical conductivity between

metal parts required to be electrically connected.

Branch circuit. The circuit conductors between the final overcurrent device protecting the

circuit and the outlets.

Building. A structure that stands alone or is cut off from adjoining structures by fire walls

with all openings therein protected by approved fire doors.

Cabinet. An enclosure designed either for surface or flush mounting, and provided with a

frame, mat, or trim in which a swinging door or doors are or can be hung.

Cable tray system. A unit or assembly of units or sections and associated fittings forming

a rigid structural system used to securely fasten or support cables and raceways. Cable

tray systems include ladders, troughs, channels, solid bottom trays, and other similar

structures.

Cablebus. An assembly of insulated conductors with fittings and conductor terminations in

a completely enclosed, ventilated, protective metal housing.

Cell line. An assembly of electrically interconnected electrolytic cells supplied by a source

of direct current power.

Cell line attachments and auxiliary equipment. Cell line attachments and auxiliary

equipment include, but are not limited to, auxiliary tanks, process piping, ductwork,

structural supports, exposed cell line conductors, conduits and other raceways, pumps,

positioning equipment, and cell cutout or bypass electrical devices. Auxiliary equipment

also includes tools, welding machines, crucibles, and other portable equipment used for

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operation and maintenance within the electrolytic cell line working zone. In the cell line

working zone, auxiliary equipment includes the exposed conductive surfaces of

ungrounded cranes and crane-mounted cell-servicing equipment.

Center pivot irrigation machine. A multi-motored irrigation machine that revolves around

a central pivot and employs alignment switches or similar devices to control individual

motors.

Certified. Equipment is "certified" if it bears a label, tag, or other record of certification

that the equipment:

(1) Has been tested and found by a nationally recognized testing laboratory to meet

nationally recognized standards or to be safe for use in a specified manner; or

(2) Is of a kind whose production is periodically inspected by a nationally recognized

testing laboratory and is accepted by the laboratory as safe for its intended use.

Circuit breaker. A device designed to open and close a circuit by nonautomatic means

and to open the circuit automatically on a predetermined overcurrent without damage to

itself when properly applied within its rating.

Class I locations. Class I locations are those in which flammable gases or vapors are or

may be present in the air in quantities sufficient to produce explosive or ignitable

mixtures. Class I locations include the following:

(1) Class I, Division 1. A Class I, Division 1 location is a location:

(i) In which ignitable concentrations of flammable gases or vapors may exist under

normal operating conditions; or

(ii) In which ignitable concentrations of such gases or vapors may exist frequently

because of repair or maintenance operations or because of leakage; or

(iii) In which breakdown or faulty operation of equipment or processes might release

ignitable concentrations of flammable gases or vapors, and might also cause

simultaneous failure of electric equipment.

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Note to the definition of "Class I, Division 1:" This classification usually includes

locations where volatile flammable liquids or liquefied flammable gases are transferred

from one container to another; interiors of spray booths and areas in the vicinity of

spraying and painting operations where volatile flammable solvents are used; locations

containing open tanks or vats of volatile flammable liquids; drying rooms or

compartments for the evaporation of flammable solvents; locations containing fat and oil

extraction equipment using volatile flammable solvents; portions of cleaning and dyeing

plants where flammable liquids are used; gas generator rooms and other portions of gas

manufacturing plants where flammable gas may escape; inadequately ventilated pump

rooms for flammable gas or for volatile flammable liquids; the interiors of refrigerators

and freezers in which volatile flammable materials are stored in open, lightly stoppered,

or easily ruptured containers; and all other locations where ignitable concentrations of

flammable vapors or gases are likely to occur in the course of normal operations.

(2) Class I, Division 2. A Class I, Division 2 location is a location:

(i) In which volatile flammable liquids or flammable gases are handled, processed, or

used, but in which the hazardous liquids, vapors, or gases will normally be confined

within closed containers or closed systems from which they can escape only in the event

of accidental rupture or breakdown of such containers or systems, or as a result of

abnormal operation of equipment; or

(ii) In which ignitable concentrations of gases or vapors are normally prevented by

positive mechanical ventilation, and which might become hazardous through failure or

abnormal operations of the ventilating equipment; or

(iii) That is adjacent to a Class I, Division 1 location, and to which ignitable

concentrations of gases or vapors might occasionally be communicated unless such

communication is prevented by adequate positive-pressure ventilation from a source of

clean air, and effective safeguards against ventilation failure are provided.

Note to the definition of "Class I, Division 2:" This classification usually includes

locations where volatile flammable liquids or flammable gases or vapors are used, but

which would become hazardous only in case of an accident or of some unusual operating

condition. The quantity of flammable material that might escape in case of accident, the

adequacy of ventilating equipment, the total area involved, and the record of the industry

or business with respect to explosions or fires are all factors that merit consideration in

201

determining the classification and extent of each location.

Piping without valves, checks, meters, and similar devices would not ordinarily introduce

a hazardous condition even though used for flammable liquids or gases. Locations used

for the storage of flammable liquids or liquefied or compressed gases in sealed containers

would not normally be considered hazardous unless also subject to other hazardous

conditions.

Electrical conduits and their associated enclosures separated from process fluids by a

single seal or barrier are classed as a Division 2 location if the outside of the conduit and

enclosures is a nonhazardous location.

(3) Class I, Zone 0. A Class I, Zone 0 location is a location in which one of the following

conditions exists:

(i) Ignitable concentrations of flammable gases or vapors are present continuously; or

(ii) Ignitable concentrations of flammable gases or vapors are present for long periods of

time.

Note to the definition of "Class I, Zone 0:" As a guide in determining when

flammable gases or vapors are present continuously or for long periods of time, refer to

Recommended Practice for Classification of Locations for Electrical Installations of

Petroleum Facilities Classified as Class I, Zone 0, Zone 1 or Zone 2, API RP 505-1997;

Electrical Apparatus for Explosive Gas Atmospheres, Classifications of Hazardous Areas,

IEC 79-10-1995; Area Classification Code for Petroleum Installations, Model Code -- Part

15, Institute for Petroleum; and Electrical Apparatus for Explosive Gas Atmospheres,

Classifications of Hazardous (Classified) Locations, ISA S12.24.01-1997.


conditions exists:

(i) Ignitable concentrations of flammable gases or vapors are likely to exist under normal

operating conditions; or

(ii) Ignitable concentrations of flammable gases or vapors may exist frequently because

of repair or maintenance operations or because of leakage; or

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(iii) Equipment is operated or processes are carried on of such a nature that equipment

breakdown or faulty operations could result in the release of ignitable concentrations of

flammable gases or vapors and also cause simultaneous failure of electric equipment in a

manner that would cause the electric equipment to become a source of ignition; or

(iv) A location that is adjacent to a Class I, Zone 0 location from which ignitable

concentrations of vapors could be communicated, unless communication is prevented by

adequate positive pressure ventilation from a source of clean air and effective safeguards

against ventilation failure are provided.


conditions exists:

(i) Ignitable concentrations of flammable gases or vapors are not likely to occur in normal

operation and if they do occur will exist only for a short period; or

(ii) Volatile flammable liquids, flammable gases, or flammable vapors are handled,

processed, or used, but in which the liquids, gases, or vapors are normally confined

within closed containers or closed systems from which they can escape only as a result of

accidental rupture or breakdown of the containers or system or as the result of the

abnormal operation of the equipment with which the liquids or gases are handled,

processed, or used; or

(iii) Ignitable concentrations of flammable gases or vapors normally are prevented by

positive mechanical ventilation, but which may become hazardous as the result of failure

or abnormal operation of the ventilation equipment; or

(iv) A location that is adjacent to a Class I, Zone 1 location, from which ignitable

concentrations of flammable gases or vapors could be communicated, unless such

communication is prevented by adequate positive-pressure ventilation from a source of

clean air, and effective safeguards against ventilation failure are provided.

Class II locations. Class II locations are those that are hazardous because of the presence

of combustible dust. Class II locations include the following:

(1) Class II, Division 1. A Class II, Division 1 location is a location:

203

(i) In which combustible dust is or may be in suspension in the air under normal

operating conditions, in quantities sufficient to produce explosive or ignitable mixtures; or

(ii) Where mechanical failure or abnormal operation of machinery or equipment might

cause such explosive or ignitable mixtures to be produced, and might also provide a

source of ignition through simultaneous failure of electric equipment, through operation

of protection devices, or from other causes; or

(iii) In which combustible dusts of an electrically conductive nature may be present.

Note to the definition of "Class II, Division 1:" This classification may include areas

of grain handling and processing plants, starch plants, sugar-pulverizing plants,

maltingplants, hay-grinding plants, coal pulverizing plants, areas where metal dusts and

powders are produced or processed, and other similar locations that contain dust

producing machinery and equipment (except where the equipment is dust-tight or vented

to the outside). These areas would have combustible dust in the air, under normal

operating conditions, in quantities sufficient to produce explosive or ignitable mixtures.

Combustible dusts that are electrically nonconductive include dusts produced in the

handling and processing of grain and grain products, pulverized sugar and cocoa, dried

egg and milk powders, pulverized spices, starch and pastes, potato and wood flour, oil

meal from beans and seed, dried hay, and other organic materials which may produce

combustible dusts when processed or handled. Dusts containing magnesium or aluminum

are particularly hazardous, and the use of extreme caution is necessary to avoid ignition

and explosion.

(2) Class II, Division 2. A Class II, Division 2 location is a location where:

(i) Combustible dust will not normally be in suspension in the air in quantities sufficient to

produce explosive or ignitable mixtures, and dust accumulations will normally be

insufficient to interfere with the normal operation of electric equipment or other

apparatus, but combustible dust may be in suspension in the air as a result of infrequent

malfunctioning of handling or processing equipment; and

(ii) Resulting combustible dust accumulations on, in, or in the vicinity of the electric

equipment may be sufficient to interfere with the safe dissipation of heat from electric

equipment or may be ignitable by abnormal operation or failure of electric equipment.

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Note to the definition of "Class II, Division 2:" This classification includes locations

where dangerous concentrations of suspended dust would not be likely, but where dust

accumulations might form on or in the vicinity of electric equipment. These areas may

contain equipment from which appreciable quantities of dust would escape under

abnormal operating conditions or be adjacent to a Class II Division 1 location, as

described above, into which an explosive or ignitable concentration of dust may be put

into suspension under abnormal operating conditions.

Class III locations. Class III locations are those that are hazardous because of the

presence of easily ignitable fibers or flyings, but in which such fibers or flyings are not

likely to be in suspension in the air in quantities sufficient to produce ignitable mixtures.

Class III locations include the following:

(1) Class III, Division 1. A Class III, Division 1 location is a location in which easily

ignitable fibers or materials producing combustible flyings are handled, manufactured, or

used.

Note to the definition of "Class III, Division 1:" Such locations usually include some

parts of rayon, cotton, and other textile mills; combustible fiber manufacturing and

processing plants; cotton gins and cotton-seed mills; flax-processing plants; clothing

manufacturing plants; woodworking plants, and establishments; and industries involving

similar hazardous processes or conditions.

Easily ignitable fibers and flyings include rayon, cotton (including cotton linters and

cotton waste), sisal or henequen, istle, jute, hemp, tow, cocoa fiber, oakum, baled waste

kapok, Spanish moss, excelsior, and other materials of similar nature.

(2) Class III, Division 2. A Class III, Division 2 location is a location in which easily

ignitable fibers are stored or handled, other than in the process of manufacture.

Collector ring. An assembly of slip rings for transferring electric energy from a stationary

to a rotating member.

Competent Person. One who is capable of identifying existing and predictable hazards in

the surroundings or working conditions that are unsanitary, hazardous, or dangerous to

employees and who has authorization to take prompt corrective measures to eliminate

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them.

Concealed. Rendered inaccessible by the structure or finish of the building. Wires in

concealed raceways are considered concealed, even though they may become accessible

by withdrawing them. (See Accessible. (As applied to wiring methods.))

Conductor --

(1) Bare. A conductor having no covering or electrical insulation whatsoever.

(2) Covered. A conductor encased within material of composition or thickness that is not

recognized by this subpart as electrical insulation.

(3) Insulated. A conductor encased within material of composition and thickness that is

recognized by this subpart as electrical insulation.

Conduit body. A separate portion of a conduit or tubing system that provides access

through one or more removable covers to the interior of the system at a junction of two

or more sections of the system or at a terminal point of the system. Boxes such as FS

and FD or larger cast or sheet metal boxes are not classified as conduit bodies.

Controller. A device or group of devices that serves to govern, in some predetermined

manner, the electric power delivered to the apparatus to which it is connected.

Covered conductor. See Conductor.

Cutout. (Over 600 volts, nominal.) An assembly of a fuse support with either a

fuseholder, fuse carrier, or disconnecting blade. The fuseholder or fuse carrier may

include a conducting element (fuse link), or may act as the disconnecting blade by the

inclusion of a nonfusible member.

Cutout box. An enclosure designed for surface mounting and having swinging doors or

covers secured directly to and telescoping with the walls of the box proper. (See

Cabinet.)

Damp location. See Location.

206

Dead front. Without live parts exposed to a person on the operating side of the

equipment

Deenergized. Free from any electrical connection to a source of potential difference and

from electrical charge; not having a potential different from that of the earth.

Device. A unit of an electrical system that is intended to carry but not utilize electric

energy.

Dielectric heating. The heating of a nominally insulating material due to its own dielectric

losses when the material is placed in a varying electric field.

Disconnecting means. A device, or group of devices, or other means by which the

conductors of a circuit can be disconnected from their source of supply.

Disconnecting (or Isolating) switch. (Over 600 volts, nominal.) A mechanical switching

device used for isolating a circuit or equipment from a source of power.

Electrolytic cell line working zone. The cell line working zone is the space envelope

wherein operation or maintenance is normally performed on or in the vicinity of exposed

energized surfaces of electrolytic cell lines or their attachments.

Electrolytic cells. A tank or vat in which electrochemical reactions are caused by applying

energy for the purpose of refining or producing usable materials.

Enclosed. Surrounded by a case, housing, fence, or walls that will prevent persons from

accidentally contacting energized parts.

Enclosure. The case or housing of apparatus, or the fence or walls surrounding an

installation to prevent personnel from accidentally contacting energized parts, or to

protect the equipment from physical damage.

Energized. Electrically connected to a source of potential difference.

Equipment. A general term including material, fittings, devices, appliances, fixtures,

apparatus, and the like, used as a part of, or in connection with, an electrical installation.

207

Equipment grounding conductor. See Grounding conductor, equipment.

Explosion-proof apparatus. Apparatus enclosed in a case that is capable of withstanding

an explosion of a specified gas or vapor that may occur within it and of preventing the

ignition of a specified gas or vapor surrounding the enclosure by sparks, flashes, or

explosion of the gas or vapor within, and that operates at such an external temperature

that it will not ignite a surrounding flammable atmosphere.

Exposed. (As applied to live parts.) Capable of being inadvertently touched or approached

nearer than a safe distance by a person. It is applied to parts not suitably guarded,

isolated, or insulated. (See Accessible and Concealed.)

Exposed. (As applied to wiring methods.) On or attached to the surface, or behind panels

designed to allow access. (See Accessible. (As applied to wiring methods.))

Exposed. (For the purposes of § 1910.308(e).) Where the circuit is in such a position that

in case of failure of supports or insulation, contact with another circuit may result.

Externally operable. Capable of being operated without exposing the operator to contact

with live parts.

Feeder. All circuit conductors between the service equipment, the source of a separate

derived system, or other power supply source and the final branch-circuit overcurrent

device.

Fitting. An accessory such as a locknut, bushing, or other part of a wiring system that is

intended primarily to perform a mechanical rather than an electrical function.

Fountain. Fountains, ornamental pools, display pools, and reflection pools.

Note to the definition of "fountain:" This definition does not include drinking

fountains.

Fuse. (Over 600 volts, nominal.) An overcurrent protective device with a circuit opening

fusible part that is heated and severed by the passage of overcurrent through it. A fuse

comprises all the parts that form a unit capable of performing the prescribed functions. It

may or may not be the complete device necessary to connect it into an electrical circuit.

208

Ground. A conducting connection, whether intentional or accidental, between an electric

circuit or equipment and the earth, or to some conducting body that serves in place of

the earth.

Grounded. Connected to the earth or to some conducting body that serves in place of the

earth.

Grounded, effectively. Intentionally connected to earth through a ground connection or

connections of sufficiently low impedance and having sufficient current-carrying capacity

to prevent the buildup of voltages that may result in undue hazards to connected

equipment or to persons.

Grounded conductor. A system or circuit conductor that is intentionally grounded.

Grounding conductor. A conductor used to connect equipment or the grounded circuit of a

wiring system to a grounding electrode or electrodes.

Grounding conductor, equipment. The conductor used to connect the noncurrent-carrying

metal parts of equipment, raceways, and other enclosures to the system grounded

conductor, the grounding electrode conductor, or both, at the service equipment or at the

source of a separately derived system.

Grounding electrode conductor. The conductor used to connect the grounding electrode

to the equipment grounding conductor, to the grounded conductor, or to both, of the

circuits at the service equipment or at the source of a separately derived system.

Ground-fault circuit-interrupter. A device intended for the protection of personnel that

functions to deenergize a circuit or a portion of a circuit within an established period of

time when a current to ground exceeds some predetermined value that is less than that

required to operate the overcurrent protective device of the supply circuit.

Guarded. Covered, shielded, fenced, enclosed, or otherwise protected by means of

suitable covers, casings, barriers, rails, screens, mats, or platforms to remove the

likelihood of approach to a point of danger or contact by persons or objects.

Health care facilities. Buildings or portions of buildings in which medical, dental,

209

psychiatric, nursing, obstetrical, or surgical care are provided.

Note to the definition of "health care facilities:" Health care facilities include, but

are not limited to, hospitals, nursing homes, limited care facilities, clinics, medical and

dental offices, and ambulatory care centers, whether permanent or movable.

Heating equipment. For the purposes of § 1910.306(g), the term "heating equipment"

includes any equipment used for heating purposes if heat is generated by induction or

dielectric methods.

Hoistway. Any shaftway, hatchway, well hole, or other vertical opening or space that is

designed for the operation of an elevator or dumbwaiter.

Identified (as applied to equipment). Approved as suitable for the specific purpose,

function, use, environment, or application, where described in a particular requirement.

Note to the definition of "identified:" Some examples of ways to determine suitability

of equipment for a specific purpose, environment, or application include investigations by

a nationally recognized testing laboratory (through listing and labeling), inspection

agency, or other organization recognized under the definition of "acceptable."

Induction heating. The heating of a nominally conductive material due to its own I\2\R

losses when the material is placed in a varying electromagnetic field.

Insulated. Separated from other conducting surfaces by a dielectric (including air space)

offering a high resistance to the passage of current.

Insulated conductor. See Conductor, Insulated.

Interrupter switch. (Over 600 volts, nominal.) A switch capable of making, carrying, and

interrupting specified currents.

Irrigation Machine. An electrically driven or controlled machine, with one or more motors,

not hand portable, and used primarily to transport and distribute water for agricultural

purposes.

Isolated. (As applied to location.) Not readily accessible to persons unless special means

210

for access are used.

Isolated power system. A system comprising an isolating transformer or its equivalent, a

line isolation monitor, and its ungrounded circuit conductors.

Labeled. Equipment is "labeled" if there is attached to it a label, symbol, or other

identifying mark of a nationally recognized testing laboratory:

(1) That makes periodic inspections of the production of such equipment, and

(2) Whose labeling indicates compliance with nationally recognized standards or tests to

determine safe use in a specified manner.

Lighting outlet. An outlet intended for the direct connection of a lampholder, a lighting

fixture, or a pendant cord terminating in a lampholder.

Line-clearance tree trimming. The pruning, trimming, repairing, maintaining, removing,

or clearing of trees or cutting of brush that is within 305 cm (10 ft) of electric supply lines

and equipment.

Listed. Equipment is "listed" if it is of a kind mentioned in a list that:

(1) Is published by a nationally recognized laboratory that makes periodic inspection of

the production of such equipment, and

(2) States that such equipment meets nationally recognized standards or has been tested

and found safe for use in a specified manner.

Live parts. Energized conductive components.

Location --

(1) Damp location. Partially protected locations under canopies, marquees, roofed open

porches, and like locations, and interior locations subject to moderate degrees of

moisture, such as some basements, some barns, and some cold-storage warehouses.

(2) Dry location. A location not normally subject to dampness or wetness. A location

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classified as dry may be temporarily subject to dampness or wetness, as in the case of a

building under construction.

(3) Wet location. Installations underground or in concrete slabs or masonry in direct

contact with the earth, and locations subject to saturation with water or other liquids,

such as vehicle-washing areas, and locations unprotected and exposed to weather.

Medium voltage cable (Type MV). A single or multiconductor solid dielectric insulated

cable rated 2001 volts or higher.

Metal-clad cable (Type MC). A factory assembly of one or more insulated circuit

conductors with or without optical fiber members enclosed in an armor of interlocking

metal tape, or a smooth or corrugated metallic sheath.

Mineral-insulated metal-sheathed cable (Type MI). Type MI, mineral-insulated metal-

sheathed, cable is a factory assembly of one or more conductors insulated with a highly

compressed refractory mineral insulation and enclosed in a liquidtight and gastight

continuous copper or alloy steel sheath.

Mobile X-ray. X-ray equipment mounted on a permanent base with wheels or casters or

both for moving while completely assembled.

Motor control center. An assembly of one or more enclosed sections having a common

power bus and principally containing motor control units.

Nonmetallic-sheathed cable (Types NM, NMC, and NMS). A factory assembly of two or

more insulated conductors having an outer sheath of moisture resistant, flame-retardant,

nonmetallic material.

Oil (filled) cutout. (Over 600 volts, nominal.) A cutout in which all or part of the fuse

support and its fuse link or disconnecting blade are mounted in oil with complete

immersion of the contacts and the fusible portion of the conducting element (fuse link),

so that arc interruption by severing of the fuse link or by opening of the contacts will

occur under oil.

Open wiring on insulators. Open wiring on insulators is an exposed wiring method using

cleats, knobs, tubes, and flexible tubing for the protection and support of single insulated

212

conductors run in or on buildings, and not concealed by the building structure.

Outlet. A point on the wiring system at which current is taken to supply utilization

equipment.

Outline lighting. An arrangement of incandescent lamps or electric discharge lighting to

outline or call attention to certain features, such as the shape of a building or the

decoration of a window.

Overcurrent. Any current in excess of the rated current of equipment or the ampacity of a

conductor. It may result from overload, short circuit, or ground fault.

Overhaul means to perform a major replacement, modification, repair, or rehabilitation

similar to that involved when a new building or facility is built, a new wing is added, or an

entire floor is renovated.

Overload. Operation of equipment in excess of normal, full-load rating, or of a conductor

in excess of rated ampacity that, when it persists for a sufficient length of time, would

cause damage or dangerous overheating. A fault, such as a short circuit or ground fault,

is not an overload. (See Overcurrent.)

Panelboard. A single panel or group of panel units designed for assembly in the form of a

single panel; including buses, automatic overcurrent devices, and with or without

switches for the control of light, heat, or power circuits; designed to be placed in a

cabinet or cutout box placed in or against a wall or partition and accessible only from the

front. (See Switchboard.)

Permanently installed decorative fountains and reflection pools. Pools that are

constructed in the ground, on the ground, or in a building in such a manner that the

fountain or pool cannot be readily disassembled for storage, whether or not served by

electrical circuits of any nature. These units are primarily constructed for their aesthetic

value and are not intended for swimming or wading.

Permanently installed swimming, wading, and therapeutic pools. Pools that are

constructed in the ground or partially in the ground, and all other capable of holding

water in a depth greater than 1.07 m (42 in.). The definition also applies to all pools

installed inside of a building, regardless of water depth, whether or not served by electric

213

circuits of any nature.

Portable X-ray. X-ray equipment designed to be hand-carried.

Power and control tray cable (Type TC). A factory assembly of two or more insulated

conductors, with or without associated bare or covered grounding conductors under a

nonmetallic sheath, approved for installation in cable trays, in raceways, or where

supported by a messenger wire.

Power fuse. (Over 600 volts, nominal.) See Fuse.

Power-limited tray cable (Type PLTC). A factory assembly of two or more insulated

conductors under a nonmetallic jacket.

Power outlet. An enclosed assembly, which may include receptacles, circuit breakers,

fuseholders, fused switches, buses, and watt-hour meter mounting means, that is

intended to supply and control power to mobile homes, recreational vehicles, or boats or

to serve as a means for distributing power needed to operate mobile or temporarily

installed equipment.

Premises wiring. (Premises wiring system.) The interior and exterior wiring, including

power, lighting, control, and signal circuit wiring together with all of their associated

hardware, fittings, and wiring devices, both permanently and temporarily installed, that

extends from the service point of utility conductors or source of power (such as a battery,

a solar photovoltaic system, or a generator, transformer, or converter) to the outlets.

Such wiring does not include wiring internal to appliances, fixtures, motors, controllers,

motor control centers, and similar equipment.

Qualified person. One who has received training in and has demonstrated skills and

knowledge in the construction and operation of electric equipment and installations and

the hazards involved.

Note 1 to the definition of "qualified person:" Whether an employee is considered to

be a "qualified person" will depend upon various circumstances in the workplace. For

example, it is possible and, in fact, likely for an individual to be considered "qualified"

with regard to certain equipment in the workplace, but "unqualified" as to other

equipment. (See 1910.332(b)(3) for training requirements that specifically apply to

214

qualified persons.)

Note 2 to the definition of "qualified person:" An employee who is undergoing on-

the-job training and who, in the course of such training, has demonstrated an ability to

perform duties safely at his or her level of training and who is under the direct

supervision of a qualified person is considered to be a qualified person for the

performance of those duties.

Raceway. An enclosed channel of metal or nonmetallic materials designed expressly for

holding wires, cables, or busbars, with additional functions as permitted in this standard.

Raceways include, but are not limited to, rigid metal conduit, rigid nonmetallic conduit,

intermediate metal conduit, liquidtight flexible conduit, flexible metallic tubing, flexible

metal conduit, electrical metallic tubing, electrical nonmetallic tubing, underfloor

raceways, cellular concrete floor raceways, cellular metal floor raceways, surface

raceways, wireways, and busways.

Readily accessible. Capable of being reached quickly for operation, renewal, or

inspections, so that those needing ready access do not have to climb over or remove

obstacles or to resort to portable ladders, chairs, etc. (See Accessible.)

Receptacle. A receptacle is a contact device installed at the outlet for the connection of

an attachment plug. A single receptacle is a single contact device with no other contact

device on the same yoke. A multiple receptacle is two or more contact devices on the

same yoke.

Receptacle outlet. An outlet where one or more receptacles are installed.

Remote-control circuit. Any electric circuit that controls any other circuit through a relay

or an equivalent device.

Sealable equipment. Equipment enclosed in a case or cabinet that is provided with a

means of sealing or locking so that live parts cannot be made accessible without opening

the enclosure. The equipment may or may not be operable without opening the

enclosure.

Separately derived system. A premises wiring system whose power is derived from a

battery, a solar photovoltaic system, or from a generator, transformer, or converter

215

windings, and that has no direct electrical connection, including a solidly connected

grounded circuit conductor, to supply conductors originating in another system.

Service. The conductors and equipment for delivering electric energy from the serving

utility to the wiring system of the premises served.

Service cable. Service conductors made up in the form of a cable.

Service conductors. The conductors from the service point to the service disconnecting

means.

Service drop. The overhead service conductors from the last pole or other aerial support

to and including the splices, if any, connecting to the service-entrance conductors at the

building or other structure.

Service-entrance cable. A single conductor or multiconductor assembly provided with or

without an overall covering, primarily used for services, and is of the following types:

(1) Type SE. Type SE, having a flame-retardant, moisture resistant covering; and

(2) Type USE. Type USE, identified for underground use, having a moisture-resistant

covering, but not required to have a flame-retardant covering. Cabled, single-conductor,

Type USE constructions recognized for underground use may have a bare copper

conductor cabled with the assembly. Type USE single, parallel, or cable conductor

assemblies recognized for underground use may have a bare copper concentric conductor

applied. These constructions do not require an outer overall covering.

Service-entrance conductors, overhead system. The service conductors between the

terminals of the service equipment and a point usually outside the building, clear of

building walls, where joined by tap or splice to the service drop.

Service entrance conductors, underground system. The service conductors between the

terminals of the service equipment and the point of connection to the service lateral.

Service equipment. The necessary equipment, usually consisting of one or more circuit

breakers or switches and fuses, and their accessories, connected to the load end of

service conductors to a building or other structure, or an otherwise designated area, and

216

intended to constitute the main control and cutoff of the supply.

Service point. The point of connection between the facilities of the serving utility and the

premises wiring.

Shielded nonmetallic-sheathed cable (Type SNM). A factory assembly of two or more

insulated conductors in an extruded core of moisture-resistant, flame-resistant

nonmetallic material, covered with an overlapping spiral metal tape and wire shield and

jacketed with an extruded moisture-, flame-, oil-, corrosion-, fungus-, and sunlight-

resistant nonmetallic material.

Show window. Any window used or designed to be used for the display of goods or

advertising material, whether it is fully or partly enclosed or entirely open at the rear and

whether or not it has a platform raised higher than the street floor level.

Signaling circuit. Any electric circuit that energizes signaling equipment.

Storable swimming or wading pool. A pool that is constructed on or above the ground and

is capable of holding water to a maximum depth of 1.07 m (42 in.), or a pool with

nonmetallic, molded polymeric walls or inflatable fabric walls regardless of dimension.

Switchboard. A large single panel, frame, or assembly of panels on which are mounted,

on the face or back, or both, switches, overcurrent and other protective devices, buses,

and (usually) instruments. Switchboards are generally accessible from the rear as well as

from the front and are not intended to be installed in cabinets. (See Panelboard.)

Switch --

(1) General-use switch. A switch intended for use in general distribution and branch

circuits. It is rated in amperes, and it is capable of interrupting its rated current at its

rated voltage.

(2) General-use snap switch. A form of general-use switch constructed so that it can be

installed in device boxes or on box covers, or otherwise used in conjunction with wiring

systems recognized by this subpart.

(3) Isolating switch. A switch intended for isolating an electric circuit from the source of

217

power. It has no interrupting rating, and it is intended to be operated only after the

circuit has been opened by some other means.

(4) Motor-circuit switch. A switch, rated in horsepower, capable of interrupting the

maximum operating overload current of a motor of the same horsepower rating as the

switch at the rated voltage.

Switching devices. (Over 600 volts, nominal.) Devices designed to close and open one or

more electric circuits. Included in this category are circuit breakers, cutouts,

disconnecting (or isolating) switches, disconnecting means, interrupter switches, and oil

(filled) cutouts.

Transportable X-ray. X-ray equipment installed in a vehicle or that may readily be

disassembled for transport in a vehicle.

Utilization equipment. Equipment that utilizes electric energy for electronic,

electromechanical, chemical, heating, lighting, or similar purposes.

Ventilated. Provided with a means to permit circulation of air sufficient to remove an

excess of heat, fumes, or vapors.

Volatile flammable liquid. A flammable liquid having a flash point below 38 ºC (100 ºF),

or a flammable liquid whose temperature is above its flash point, or a Class II

combustible liquid having a vapor pressure not exceeding 276 kPa (40 psia) at 38 ºC

(100 ºF) and whose temperature is above its flash point.

Voltage (of a circuit). The greatest root-mean-square (rms) (effective) difference of

potential between any two conductors of the circuit concerned.

Voltage, nominal. A nominal value assigned to a circuit or system for the purpose of

conveniently designating its voltage class (as 120/240 volts, 480Y/277 volts, 600 volts).

The actual voltage at which a circuit operates can vary from the nominal within a range

that permits satisfactory operation of equipment.

Voltage to ground. For grounded circuits, the voltage between the given conductor and

that point or conductor of the circuit that is grounded; for ungrounded circuits, the

greatest voltage between the given conductor and any other conductor of the circuit.

218

Watertight. So constructed that moisture will not enter the enclosure.

Weatherproof. So constructed or protected that exposure to the weather will not interfere

with successful operation. Rainproof, raintight, or watertight equipment can fulfill the

requirements for weatherproof where varying weather conditions other than wetness,

such as snow, ice, dust, or temperature extremes, are not a factor.

Wireways. Sheet-metal troughs with hinged or removable covers for housing and

protecting electric wires and cable and in which conductors are laid in place after the

wireway has been installed as a complete system.

[46 FR 4056, Jan. 16, 1981; 46 FR 40185, Aug. 7, 1981; as amended at 53 FR 12123,

Apr. 12, 1988; 55 FR 32020, Aug. 6, 1990; 55 FR 46054, Nov. 1, 1990; 72 7215, Feb.

14, 2007]

219

220


Reference Documents - 1910 Subpart S App A



• Subpart: S


• Standard Number: 1910 Subpart S App A

• Title: Reference Documents

The references contained in this appendix provide nonmandatory information that can be

helpful in understanding and complying with Subpart S of this Part. However, compliance

with these standards is not a substitute for compliance with Subpart S of this Part.

ANSI/API RP 500-1998 (2002) Recommended Practice for Classification of Locations for

Electrical Installations at Petroleum Facilities Classified as Class I Division 1 and Division

2.

ANSI/API RP 505-1997 (2002) Recommended Practice for Classification of Locations for

Electrical Installations at Petroleum Facilities Classified as Class I, Zone 0, Zone 1 and

Zone 2.

ANSI/ASME A17.1-2004 Safety Code for Elevators and Escalators.

ANSI/ASME B30.2-2005 Overhead and Gantry Cranes (Top Running Bridge, Single or

Multiple Girder, Top Running Trolley Hoist).

ANSI/ASME B30.3-2004 Construction Tower Cranes.

ANSI/ASME B30.4-2003 Portal, Tower, and Pedestal Cranes.

ANSI/ASME B30.5-2004 Mobile And Locomotive Cranes.

ANSI/ASME B30.6-2003 Derricks.

221

ANSI/ASME B30.7-2001 Base Mounted Drum Hoists.

ANSI/ASME B30.8-2004 Floating Cranes And Floating Derricks.

ANSI/ASME B30.11-2004 Monorails And Underhung Cranes.

ANSI/ASME B30.12-2001 Handling Loads Suspended from Rotorcraft.

ANSI/ASME B30.13-2003 Storage/Retrieval (S/R) Machines and Associated Equipment.

ANSI/ASME B30.16-2003 Overhead Hoists (Underhung).

ANSI/ASME B30.22-2005 Articulating Boom Cranes.

ANSI/ASSE Z244.1-2003 Control of Hazardous Energy Lockout/Tagout and Alternative

Methods.

ANSI/ASSE Z490.1-2001 Criteria for Accepted Practices in Safety, Health, and

Environmental Training.

ANSI/IEEE C2-2002 National Electrical Safety Code.

ANSI K61.1-1999 Safety Requirements for the Storage and Handling of Anhydrous

Ammonia.

ANSI/UL 913-2003 Intrinsically Safe Apparatus and Associated Apparatus for Use in Class

I, II, and III, Division 1, Hazardous (Classified) Locations.

ASTM D3176-1989 (2002) Standard Practice for Ultimate Analysis of Coal and Coke.

ASTM D3180-1989 (2002) Standard Practice for Calculating Coal and Coke Analyses from

As-Determined to Different Bases.

NFPA 20-2003 Standard for the Installation of Stationary Pumps for Fire Protection.

NFPA 30-2003 Flammable and Combustible Liquids Code.

222

NFPA 32-2004 Standard for Drycleaning Plants.

NFPA 33-2003 Standard for Spray Application Using Flammable or Combustible Materials.

NFPA 34-2003 Standard for Dipping and Coating Processes Using Flammable or

Combustible Liquids.

NFPA 35-2005 Standard for the Manufacture of Organic Coatings.

NFPA 36-2004 Standard for Solvent Extraction Plants.

NFPA 40-2001 Standard for the Storage and Handling of Cellulose Nitrate Film.

NFPA 58-2004 Liquefied Petroleum Gas Code.

NFPA 59-2004 Utility LP-Gas Plant Code.

NFPA 70-2002 National Electrical Code. (See also NFPA 70-2005.)

NFPA 70E-2000 Standard for Electrical Safety Requirements for Employee Workplaces.

(See also NFPA 70E-2004.)

NFPA 77-2000 Recommended Practice on Static Electricity.

NFPA 80-1999 Standard for Fire Doors and Fire Windows.

NFPA 88A-2002 Standard for Parking Structures.

NFPA 91-2004 Standard for Exhaust Systems for Air Conveying of Vapors, Gases, Mists,

and Noncombustible Particulate Solids.

NFPA 101-2006 Life Safety Code.

NFPA 496-2003 Standard for Purged and Pressurized Enclosures for Electrical Equipment.

NFPA 497-2004 Recommended Practice for the Classification of Flammable Liquids,

223

Gases, or Vapors and of Hazardous (Classified) Locations for Electrical Installations in

Chemical Process Areas.

NFPA 505-2006 Fire Safety Standard for Powered Industrial Trucks Including Type

Designations, Areas of Use, Conversions, Maintenance, and Operation.

NFPA 820-2003 Standard for Fire Protection in Wastewater Treatment and Collection

Facilities.

NMAB 353-1-1979 Matrix of Combustion-Relevant Properties and Classification of Gases,

Vapors, and Selected Solids.

NMAB 353-2-1979 Test Equipment for Use in Determining Classifications of Combustible

Dusts.

NMAB 353-3-1980 Classification of Combustible Dust in Accordance with the National

Electrical Code.

[46 FR 4056, Jan. 16, 1981; 46 FR 40185, Aug. 7, 1981; 55 FR 32020, Aug. 6, 1990; 72

FR 7221, Feb. 14, 2007]

224

225

U.S. Department of LaborElaine L. Chao, Secretary

Occupational Safety and Health AdministrationJohn L. Henshaw, Assistant Secretary

OSHA 31202002 (Revised)

Control ofHazardous EnergyLockout/Tagout

226

Contents i

Contents

Page

Background ............................................................................... 1

How should I use this booklet? ............................................ 1

What is “lockout/tagout”? .................................................... 1

Why do I need to be concernedabout lockout/tagout? ........................................................... 2

OSHA Coverage ........................................................................ 3

How do I know if the OSHA standardapplies to me? ....................................................................... 3

When does the standard not apply toservice and maintenance activities performedin industries covered by Part 1910? ..................................... 3

How does the standard apply to generalindustry service and maintenance operations? .................... 4

Requirements of the Standard ................................................. 6

What are OSHA’s requirements? ......................................... 6

What must an energy-control procedure include? ............... 7

What must workers do before theybegin service or maintenance activities? ............................. 8

What must workers do before theyremove their lockout or tagout deviceand reenergize the machine? ................................................ 8

When do I use lockout and how do I do it? ......................... 9

How can I determine if the energy-isolatingdevice can be locked out? .................................................. 10

What do I do if I cannot lock outthe equipment? ................................................................... 10

227

Control of Hazardous Energy (Lockout/Tagout)ii

What other options do I have? ............................................11

When can tagout devices be usedinstead of lockout devices? .................................................11

What are the limitations of tagout devices? ....................... 12

What are the requirements forlockout/tagout devices? ...................................................... 12

What do employees need to knowabout lockout/tagout programs? ......................................... 13

When is training necessary? ............................................... 14

What if I need power to test or positionmachines, equipment, or components? .............................. 15

What if I use outside contractors forservice or maintenance procedures? .................................. 16

What if a group performs serviceor maintenance activities? .................................................. 16

What if a shift changes duringmachine service or maintenance? ...................................... 16

How often do I need to reviewmy lockout/tagout procedures? .......................................... 17

What does a review entail? ................................................ 17

What additional information does OSHAprovide about lockout/tagout? ............................................ 18

Commonly Used Terms .......................................................... 20

OSHA Assistance, Programs, and Services .......................... 22

How can OSHA help me? .................................................. 22

How does safety and health program managementassistance help employers and employees? ....................... 22

228

Contents iii

What are state plans? .......................................................... 23

How can consultation assistancehelp employers? ................................................................. 23

Who can get consultation assistanceand what does it cost? ........................................................ 24

Can OSHA assure privacy to an employerwho asks for consultation assistance? ................................ 24

Can an employer be cited for violationsafter receiving consultation assistance? ............................. 24

What incentives does OSHA provide forseeking consultation assistance? ........................................ 24

What are the Voluntary Protection Programs? ................... 25

How does the VPP work? ................................................... 25

How does VPP help employers and employees? ............... 26

How does OSHA monitor VPP sites? ................................ 26

Can OSHA inspect an employerwho is participating in the VPP? ........................................ 26

How can a partnership with OSHAimprove worker safety and health? .................................... 27

What is OSHA’s Strategic PartnershipProgram (OSPP)? ............................................................... 27

What do OSPPs do? ........................................................... 27

What are the different kinds of OSPPs? ............................ 28

What are the benefits of participation in the OSPP? ......... 28

Does OSHA have occupational safety andhealth training for employers and employees? .................. 29

Does OSHA give money to organizationsfor training and education? ................................................ 29

229

Control of Hazardous Energy (Lockout/Tagout)iv

Does OSHA have other assistancematerials available? ............................................................ 30

What do I do in case of an emergencyor to file a complaint? ........................................................ 31

OSHA Regional and Area Offices ......................................... 32

OSHA Consultation Projects ................................................. 36

OSHA-Approved Safety and Health Plans .......................... 38

230

1How should I use this booklet?

How should I use this booklet?This booklet presents OSHA’s general requirements for

controlling hazardous energy during service or maintenanceof machines or equipment. It is not intended to replace or tosupplement OSHA standards regarding the control of hazardousenergy. After reading this booklet, employers and otherinterested parties are urged to review the OSHA standardson the control of hazardous energy to gain a completeunderstanding of the requirements regarding the control ofhazardous energy. These standards, as well as other relevantresources, are identified throughout this publication.

What is �lockout/tagout�?“Lockout/tagout” refers to specific practices and procedures

to safeguard employees from the unexpected energization orstartup of machinery and equipment, or the release of hazardousenergy during service or maintenance activities.1 This requires,in part, that a designated individual turns off and disconnectsthe machinery or equipment from its energy source(s) beforeperforming service or maintenance and that the authorizedemployee(s) either lock or tag the energy-isolating device(s) toprevent the release of hazardous energy and take steps to verifythat the energy has been isolated effectively. If the potentialexists for the release of hazardous stored energy or for thereaccumulation of stored energy to a hazardous level, theemployer must ensure that the employee(s) take steps to preventinjury that may result from the release of the stored energy.

Lockout devices hold energy-isolation devices in a safe or“off” position. They provide protection by preventing machinesor equipment from becoming energized because they are

Background

1 The standard refers to servicing and maintaining “machines orequipment.” Although the terms “machine” and “equipment” havedistinct meanings, this booklet uses the term “machines” to refer bothto machines and equipment. This is done for purposes of brevity only,and readers should not infer that it is intended to limit the scope of thestandard. The term “equipment” is broad in scope and encompasses alltypes of equipment, including process equipment such as piping systems.

231

Control of Hazardous Energy (Lockout/Tagout)2

positive restraints that no one can remove without a key or otherunlocking mechanism, or through extraordinary means, such asbolt cutters. Tagout devices, by contrast, are prominent warningdevices that an authorized employee fastens to energy-isolatingdevices to warn employees not to reenergize the machine whilehe or she services or maintains it. Tagout devices are easier toremove and, by themselves, provide employees with lessprotection than do lockout devices.

Why do I need to be concerned about lockout/tagout?Employees can be seriously or fatally injured if machinery

they service or maintain unexpectedly energizes, starts up, orreleases stored energy. OSHA’s standard on the Control ofHazardous Energy (Lockout/Tagout), found in Title 29 of theCode of Federal Regulations (CFR) Part 1910.147, spells outthe steps employers must take to prevent accidents associatedwith hazardous energy. The standard addresses practices andprocedures necessary to disable machinery and prevent therelease of potentially hazardous energy while maintenance orservicing activities are performed.

Two other OSHA standards also contain energy controlprovisions: 29 CFR 1910.269 and 1910.333. In addition,some standards relating to specific types of machinery containdeenergization requirements—such as 29 CFR 1910.179(l)(2)(i)(c)(requiring the switches to be “open and locked in the open position”before performing preventive maintenance on overhead and gantrycranes).2 The provisions of Part 1910.147 apply in conjunctionwith these machine-specific standards to assure that employees willbe adequately protected against hazardous energy.

2 The standard provides a limited exception to the requirement that energycontrol procedures be documented. If an employer can demonstrate theexistence of EACH of the eight elements listed in 1910.147(c)(4)(i),the employer is not required to document the energy control procedure.However, the exception terminates if circumstances change and ANYof the elements no longer exist.

232

3

How do I know if the OSHA standard applies to me?If your employees service or maintain machines where

the unexpected startup, energization, or the release of storedenergy could cause injury, the standard likely applies to you.The standard applies to all sources of energy, including, butnot limited to: mechanical, electrical, hydraulic, pneumatic,chemical, and thermal energy.

The standard does not cover electrical hazards from workon, near, or with conductors or equipment in electric utilization(premise wiring) installations, which are outlined by Subpart Sof 29 CFR Part 1910. You can find the specific lockout andtagout provisions for electrical shock and burn hazards in29 CFR Part 1910.333. Controlling hazardous energy ininstallations for the exclusive purpose of power generation,transmission, and distribution, including related equipment forcommunication or metering, is covered by 29 CFR 1910.269.

The standard also does not cover the agriculture, construction,and maritime industries or oil and gas well drilling and servicing.Other standards concerning the control of hazardous energy,however, apply in many of these industries/situations.

When does the standard not apply to service and maintenanceactivities performed in industries covered by Part 1910?

The standard does not apply to general industry serviceand maintenance activities in the following situations, when:

• Exposure to hazardous energy is controlled completelyby unplugging the equipment from an electric outlet andwhere the employee doing the service or maintenance hasexclusive control of the plug. This applies only if electricityis the only form of hazardous energy to which employeesmay be exposed. This exception encompasses manyportable hand tools and some cord and plug connectedmachinery and equipment.

How do I know if the OSHA standard applies to me?

OSHA Coverage

233


• An employee performs hot-tap operations on pressurizedpipelines that distribute gas, steam, water, or petroleumproducts, for which the employer shows the following: – Continuity of service is essential; – Shutdown of the system is impractical; and – The employee follows documented procedures and

uses special equipment that provides proven, effectiveemployee protection.

• The employee is performing minor tool changes or otherminor servicing activities that are routine, repetitive, andintegral to production, and that occur during normalproduction operations. In these cases, employees musthave effective, alternative protection.

How does the standard apply to general industry serviceand maintenance operations?

The standard applies to the control of hazardous energy whenemployees are involved in service or maintenance activitiessuch as constructing, installing, setting up, adjusting, inspecting,modifying, and maintaining or servicing machines or equipment.These activities include lubricating, cleaning or unjammingmachines, and making adjustments or tool changes, wherethe employees may be exposed to hazardous energy.

If a service or maintenance activity is part of the normalproduction operation, the employee performing the servicingmay be subjected to hazards not normally associated withthe production operation itself. Although machine guardingprovisions in Subpart O of 29 CFR 1910 cover most normalproduction operations, workers doing service or maintenanceactivities during normal production operations must followlockout/tagout procedures if they:

• Remove or bypass machine guards or other safety devices,

• Place any part of their bodies in or near a machine’s pointof operation, or

234

5

• Place any part of their bodies in a danger zone associatedwith machine operations.

Work involving minor tool changes and adjustments orother minor servicing activities that are routine, repetitive, andintegral to the use of the production equipment and that occurduring normal production operations are not covered by thelockout/tagout standard. This exception is limited, however, andapplies only when economic considerations prevent the use ofprescribed energy-isolation measures and when the employerprovides and requires alternative measures to ensure effective,alternative protection.

Whenever the standard is applicable, the machinery mustbe shut off and isolated from its energy sources, and lockout ortagout devices must be applied to the energy-isolation devices.In addition, the authorized employee(s) must take steps to verifythat he or she has effectively isolated the energy. When thereis stored or residual energy, the authorized employee(s) musttake steps to render that energy safe. If the possibility existsfor reaccumulation of stored energy to hazardous levels, theemployer must ensure that the worker(s) perform verificationsteps regularly to detect such reaccumulation before it has thepotential to cause injury.

How does the standard apply to general industry operations?

235


What are OSHA�s requirements?OSHA’s standard establishes minimum performance

requirements for controlling hazardous energy. The standardspecifies that employers must establish an energy-controlprogram to ensure that employees isolate machines fromtheir energy sources and render them inoperative beforeany employee services or maintains them.

As part of an energy-control program, employers must:

• Establish energy-control procedures for removing theenergy supply from machines and for putting appropriatelockout or tagout devices on the energy-isolating devicesto prevent unexpected reenergization. When appropriate,the procedure also must address stored or potentiallyreaccumulated energy;

• Train employees on the energy-control program, includingthe safe application, use, and removal of energy controls;and

• Inspect these procedures periodically (at least annually)to ensure that they are being followed and that they remaineffective in preventing employee exposure to hazardousenergy.

If employers use tagout devices on machinery that can belocked out, they must adopt additional measures to provide thesame level of employee protection that lockout devices wouldprovide. Within the broad boundaries of the standard, employershave the flexibility to develop programs and procedures thatmeet the needs of their individual workplaces and the particulartypes of machines being maintained or serviced.

Requirements of the Standard

236

7

What must an energy-control procedure include?Employers must develop, document, and use procedures

to control potentially hazardous energy.3 The proceduresexplain what employees must know and do to control hazardousenergy effectively when they service or maintain machinery.If this information is the same for the various machines used ata workplace, then a single energy-control procedure may suffice.For example, similar machines (those using the same type andmagnitude of energy) that have the same or similar types ofcontrol measures can be covered by a single procedure.Employers must develop separate energy-control proceduresif their workplaces have more variable conditions such asmultiple energy sources, different power connections, ordifferent control sequences that workers must follow to shutdown various pieces of machinery.

The energy-control procedures must outline the scope,purpose, authorization, rules, and techniques that employeeswill use to control hazardous energy sources, as well asthe means that will be used to enforce compliance. Theseprocedures must provide employees at least the followinginformation:

• A statement on how to use the procedures;

• Specific procedural steps to shut down, isolate, block,and secure machines;

• Specific steps designating the safe placement, removal,and transfer of lockout/tagout devices and identifyingwho has responsibility for the lockout/tagout devices; and

• Specific requirements for testing machines to determineand verify the effectiveness of lockout devices, tagoutdevices, and other energy-control measures.

What must an energy-control procedure include?

3 The standard provides a limited exception to the requirement that energycontrol procedures be documented. If an employer can demonstrate theexistence of EACH of the eight elements listed in 1910.147(c)(4)(i),the employer is not required to document the energy control procedure.However, the exception terminates if circumstances change and ANYof the elements no longer exist.

237


In Appendix A to 1910.147, OSHA provides a TypicalMinimal Lockout Procedure for employers to consult whenpreparing their own specific energy-control procedures. Theoutline is a nonmandatory guideline to help employers andemployees comply with the standard. Nothing in the appendixadds to or detracts from any of the requirements in the standard.

What must workers do before they begin serviceor maintenance activities?

Before beginning service or maintenance, the followingsteps must be accomplished in sequence and according to thespecific provisions of the employer’s energy-control procedure:

(1) Prepare for shutdown;

(2) Shut down the machine;

(3) Disconnect or isolate the machine from the energysource(s);

(4) Apply the lockout or tagout device(s) to theenergy-isolating device(s);

(5) Release, restrain, or otherwise render safe all potentialhazardous stored or residual energy. If a possibilityexists for reaccumulation of hazardous energy, regularlyverify during the service and maintenance that suchenergy has not reaccumulated to hazardous levels; and

(6) Verify the isolation and deenergization of the machine.

What must workers do before they remove theirlockout or tagout device and reenergize the machine?

Employees who work on deenergized machinery maybe seriously injured or killed if someone removes lockout/tagoutdevices and reenergizes machinery without their knowledge.Thus, it is extremely important that all employees respect lockoutand tagout devices and that only the person(s) who applied thesedevices remove them.

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Before removing lockout or tagout devices, the employeesmust take the following steps in accordance with the specificprovisions of the employer’s energy-control procedure:

• Inspect machines or their components to assure that theyare operationally intact and that nonessential items areremoved from the area; and

• Check to assure that everyone is positioned safely andaway from machines.

After removing the lockout or tagout devices but beforereenergizing the machine, the employer must assure that allemployees who operate or work with the machine, as well asthose in the area where service or maintenance is performed,know that the devices have been removed and that the machineis capable of being reenergized. (See Sections 6(e) and (f) of29 CFR Part 1910.147 for specific requirements.) In the raresituation in which the employee who placed the lockout/tagoutdevice is unable to remove that device, another person mayremove it under the direction of the employer, provided that theemployer strictly adheres to the specific procedures outlined inthe standard. (See 29 CFR 1910.147(e)(3).)

When do I use lockout and how do I do it?You must use a lockout program (or tagout program that

provides a level of protection equal to that achieved throughlockout) whenever your employees engage in service ormaintenance operations on machines that are capable of beinglocked out and that expose them to hazardous energy fromunexpected energization, startup, or release of stored energy.

The primary way to prevent the release of hazardousenergy during service and maintenance activities is by usingenergy-isolating devices such as manually operated circuitbreakers, disconnect switches, and line valves and safetyblocks. Lockout requires use of a lock or other lockout deviceto hold the energy-isolating device in a safe position to preventmachinery from becoming reenergized. Lockout also requires

What must workers do before they remove their lockout or tagout device?

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employees to follow an established procedure to ensure thatmachinery will not be reenergized until the same employeewho placed the lockout device on the energy-isolating deviceremoves it.

How can I determine if the energy-isolating devicecan be locked out?

An energy-isolating device is considered “capable of beinglocked out” if it meets one of the following requirements:

• Is designed with a hasp or other part to which you canattach a lock such as a lockable electric disconnect switch;

• Has a locking mechanism built into it; or

• Can be locked without dismantling, rebuilding, or replacingthe energy-isolating device or permanently altering itsenergy-control capability, such as a lockable valve coveror circuit breaker blockout.

What do I do if I cannot lock out the equipment?Sometimes it is not possible to lock out the energy-isolating

device associated with the machinery. In that case, you mustsecurely fasten a tagout device as close as safely possible to theenergy-isolating device in a position where it will be immediatelyobvious to anyone attempting to operate the device. You alsomust meet all of the tagout provisions of the standard. The tagalerts employees to the hazard of reenergization and states thatemployees may not operate the machinery to which it is attacheduntil the tag is removed in accordance with an establishedprocedure.

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11What other options do I have?

What other options do I have?If it is possible to lock out an energy-isolating device,

employers must use lockout devices unless they develop,document, and use a tagout procedure that providesemployees with a level of protection equal to that providedby a lockout device. In a tagout program, an employer canattain an equal level of protection by complying with alltagout-related provisions of the standard and using at least oneadded safety measure that prevents unexpected reenergization.Such measures might include removing an isolating circuitelement, blocking a controlling switch, opening an extradisconnecting device, or removing a valve handle to minimizethe possibility that machines might inadvertently be reenergizedwhile employees perform service and maintenance activities.

When can tagout devices be used instead of lockout devices?When an energy-isolating device cannot be locked out, the

employer must modify or replace the energy-isolating deviceto make it capable of being locked out or use a tagout system.Whenever employers significantly repair, renovate, or modifymachinery or install new or replacement machinery, however,they must ensure that the energy-isolating devices for themachinery are capable of being locked out.

Tagout devices may be used on energy-isolating devicesthat are capable of being locked out if the employer developsand implements the tagout in a way that provides employeeswith a level of protection equal to that achieved through alockout system.

When using a tagout system, the employer must complywith all tagout-related provisions of the standard and trainemployees in the limitations of tags, in addition to providingnormal hazardous energy control training for all employees.

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What are the limitations of tagout devices?A tagout device is a prominent warning that clearly states

that the machinery being controlled must not be operated untilthe tag is removed in accordance with an established procedure.Tags are essentially warning devices and do not provide thephysical restraint of a lock. Tags may evoke a false sense ofsecurity. For these reasons, OSHA considers lockout devicesto be more secure and more effective than tagout devices inprotecting employees from hazardous energy.

What are the requirements for lockout/tagout devices?Whether lockout or tagout devices are used, they must

be the only devices the employer uses in conjunction withenergy-isolating devices to control hazardous energy.The employer must provide these devices and they mustbe singularly identified and not used for other purposes.In addition, they must have the following characteristics:

• Durable enough to withstand workplace conditions.Tagout devices must not deteriorate or become illegibleeven when used with corrosive components such as acidor alkali chemicals or in wet environments.

• Standardized according to color, shape, or size. Tagoutdevices also must be standardized according to print andformat. Tags must be legible and understandable by allemployees. They must warn employees about the hazardsif the machine is energized, and offer employees clearinstruction such as: “Do Not Start,” “Do Not Open,”“Do Not Close,” “Do Not Energize,” or “Do Not Operate.”

• Substantial enough to minimize the likelihood ofpremature or accidental removal. Employees should beable to remove locks only by using excessive force withspecial tools such as bolt cutters or other metal-cuttingtools. Tag attachments must be non-reusable, self-locking,and non-releasable, with a minimum unlocking strength

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of 50 pounds. Tags must be attachable by hand, andthe device for attaching the tag should be a one-piecenylon cable tie or its equivalent so it can withstand allenvironments and conditions.

• Labeled to identify the specific employees authorized toapply and remove them.

What do employees need to know about lockout/tagout programs?Training must ensure that employees understand the

purpose, function, and restrictions of the energy-controlprogram. Employers must provide training specific to theneeds of “authorized,” “affected,” and “other” employees.

“Authorized” employees are those responsible forimplementing the energy-control procedures or performingthe service or maintenance activities. They need theknowledge and skills necessary for the safe application,use, and removal of energy-isolating devices. They alsoneed training in the following:

• Hazardous energy source recognition;

• The type and magnitude of the hazardous energysources in the workplace; and

• Energy-control procedures, including the methods andmeans to isolate and control those energy sources.

“Affected” employees (usually machine operators or users)are employees who operate the relevant machinery or whosejobs require them to be in the area where service or maintenanceis performed. These employees do not service or maintainmachinery or perform lockout/tagout activities. Affectedemployees must receive training in the purpose and use ofenergy-control procedures. They also need to be able to dothe following:

• Recognize when the energy-control procedure is beingused,

What are the requirements for lockout/tagout devices?

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• Understand the purpose of the procedure, and

• Understand the importance of not tampering with lockoutor tagout devices and not starting or using equipmentthat has been locked or tagged out.

All other employees whose work operations are or maybe in an area where energy-control procedures are used mustreceive instruction regarding the energy-control procedureand the prohibition against removing a lockout or tagoutdevice and attempting to restart, reenergize, or operatethe machinery.

In addition, if tagout devices are used, all employeesmust receive training regarding the limitations of tags.(See 29 CFR 1910.147(c)(7)(ii).)

When is training necessary?The employer must provide initial training before starting

service and maintenance activities and must provide retrainingas necessary. In addition, the employer must certify thatthe training has been given to all employees covered by thestandard. The certification must contain each employee’s nameand dates of training.

Employers must provide retraining for all authorized andaffected employees whenever there is a change in the following:

• Job assignments,

• Machinery or processes that present a new hazard, or

• Energy-control procedures.

Retraining also is necessary whenever a periodic inspectionreveals, or an employer has reason to believe, that shortcomingsexist in an employee’s knowledge or use of the energy-controlprocedure.

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What if I need power to test or position machines, equipment,or components?

OSHA allows the temporary removal of lockout or tagoutdevices and the reenergization of the machine only in limitedsituations for particular tasks that require energization—forexample, when power is needed to test or position machines,equipment, or components. However, this temporary exceptionapplies only for the limited time required to perform theparticular task requiring energization. Employers must provideeffective protection from hazardous energy when employeesperform these operations. The following steps must beperformed in sequence before reenergization:

1. Clear tools and materials from machines.

2. Clear employees from the area around the machines.

3. Remove the lockout or tagout devices as specified inthe standard.

4. Energize the machine and proceed with testing orpositioning.

5. Deenergize all systems, isolate the machine from theenergy source, and reapply energy-control measuresif additional service or maintenance is required.

The employer must develop, document, and use energy-controlprocedures that establish a sequence of actions to follow wheneverreenergization is required as a part of a service or maintenanceactivity, since employees may be exposed to significant risksduring these transition periods.

What if I need power to test or position machines?

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What if I use outside contractors for serviceor maintenance procedures?

If an outside contractor services or maintains machinery,the onsite employer and the contractor must inform each otherof their respective lockout or tagout procedures. The onsiteemployer also must ensure that employees understand andcomply with all requirements of the contractor’s energy-controlprogram(s).

What if a group performs service or maintenance activities?When a crew, department, or other group performs service

or maintenance, they must use a procedure that provides allemployees a level of protection equal to that provided bya personal lockout or tagout device. Each employee in thegroup must have control over the sources of hazardous energywhile he or she is involved in service and maintenance activitiescovered by the standard. Personal control is achieved when eachauthorized employee affixes a personal lockout/tagout device toa group lockout mechanism instead of relying on a supervisoror other person to provide protection against hazardous energy.Detailed requirements of individual responsibilities are providedin 29 CFR 1910.147(f)(3)(ii)(A) through (D). Appendix C ofOSHA Directive STD 1-7.3, 29 CFR 1910.147, the Control ofHazardous Energy (Lockout/Tagout)-Inspection Proceduresand Interpretive Guidance, (September 11, 1990), providesadditional guidance.

What if a shift changes during machine service or maintenance?Employers must make sure that there is a continuity of

lockout or tagout protection. This includes the orderly transferof lockout or tagout device protection between outgoing andincoming shifts to control hazardous energy. When lockoutor tagout devices remain on energy-isolation devices froma previous shift, the incoming shift members must verifyfor themselves that the machinery is effectively isolatedand deenergized.

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How often do I need to review my lockout/tagout procedures?Employees are required to review their procedures at least

once a year to ensure that they provide adequate workerprotection. As part of the review, employers must correct anydeviations and inadequacies identified in the energy-controlprocedure or its application.

What does a review entail?The periodic inspection is intended to assure that employees

are familiar with their responsibilities under the procedure andcontinue to implement energy-control procedures properly.The inspector, who must be an authorized person not involvedin using the particular control procedure being inspected, mustbe able to determine the following:

• Employees are following steps in the energy-controlprocedure;

• Employees involved know their responsibilities underthe procedure; and

• The procedure is adequate to provide the necessaryprotection, and what changes, if any, are needed.

For a lockout procedure, the periodic inspection mustinclude a review of each authorized employee’s responsibilitiesunder the energy-control procedure being inspected. Wheretagout is used, the inspector’s review also extends to affectedemployees because of the increased importance of their role inavoiding accidental or inadvertent activation of the machinery.In addition, the employer must certify that the designatedinspectors perform periodic inspections. The certificationmust specify the following:

• Machine or equipment on which the energy-controlprocedure was used,

• Date of the inspection,

• Names of employees included in the inspection, and

• Name of the person who performed the inspection.

How often do I need to review my lockout/tagout procedures?

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What additional information does OSHA provideabout lockout/tagout?

To gain a more comprehensive understanding of therequirements for controlling hazardous energy, employersand other interested persons should review the following:

• OSHA standards with provisions regarding the control ofhazardous energy such as 29 CFR 1910.147, The controlof hazardous energy (lockout/tagout); 29 CFR 1910.269,Electric power generation, transmission, and distribution;and 29 CFR 1910.333, Selection and use of work practices.Employers in the maritime, agriculture, and constructionindustries are urged to review the provisions for the controlof hazardous energy contained in 29 CFR Parts 1915, 1917,1918, 1925, and 1926.

• The regulatory preambles to 29 CFR 1910.147(54 Federal Register 36644 (September 1, 1989)) and1910.269 (59 Federal Register 4320 (January 31, 1994)),which contain comments from interested parties andOSHA’s explanation for the provisions of the standards.

• OSHA instructions concerning the control of hazardousenergy—Directive CPL 2-1.18A, Enforcement of theElectrical Power Generation, Transmission, and DistributionStandard (October 20, 1997) and OSHA DirectiveSTD 1-7.3, 29 CFR 1910.147, the Control of HazardousEnergy (Lockout/Tagout) -Inspection Procedures andInterpretive Guidance, (September 11, 1990).

• OSHA letters of interpretation regarding the applicationof standards concerning the control of hazardous energy.

Most of these documents are available on the OSHAwebsite at www.osha.gov.

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Additionally, OSHA offers a variety of web-based tools tohelp educate employers and employees about the lockout/tagoutstandard and how to apply it in their workplace. These includethe following:

• The Lockout/Tagout Interactive Training Program, whichincludes a tutorial, five abstracts with a detailed discussionof major lockout/tagout issues involved, and interactivecase studies;

• The Lockout/Tagout Plus Expert Advisor, an interactive,expert, diagnostic software package to help usersunderstand and apply OSHA standards that protect workersfrom the release of hazardous energy; and

• The Lockout/Tagout electronic Compliance Assistant Tool(eCAT), an illustrated tool to help businesses identify andcorrect workplace hazards.

These tools are available on the OSHA website atwww.osha.gov. For the Lockout/Tagout Interactive TrainingProgram, click on Technical Links. For the Expert Advisor andeCAT, click on eTools.

What additional information does OSHA provide about lockout/tagout?

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Affected employee. An employee whose job requireshim/her to operate or use a machine or equipment on whichservicing or maintenance is being performed under lockoutor tagout, or whose job requires him/her to work in an areain which such servicing or maintenance is being performed.

Authorized employee. A person who locks out or tagsout machines or equipment in order to perform servicingor maintenance on that machine or equipment. An affectedemployee becomes an authorized employee when thatemployee’s duties include performing servicing ormaintenance covered under the standard.

Capable of being locked out. An energy-isolating device iscapable of being locked out if it has a hasp or other means ofattachment to which, or through which, a lock can be affixed, orit has a locking mechanism built into it. Other energy-isolatingdevices are capable of being locked out, if lockout can be achieved,without the need to dismantle, rebuild, or replace the energy-isolating device or permanently alter its energy control capability.

Energized. Connected to an energy source or containingresidual or stored energy.

Energy-isolating device. A mechanical device that physicallyprevents the transmission or release of energy, including but notlimited to the following: a manually operated electrical circuitbreaker; a disconnect switch; a manually operated switch bywhich the conductors of a circuit can be disconnected fromall ungrounded supply conductors, and in addition, no polecan be operated independently; a line valve; a block; and anysimilar device used to block or isolate energy. Push buttons,selector switches and other control circuit-type devices arenot energy-isolating devices.

Energy source. Any source of electrical, mechanical,hydraulic, pneumatic, chemical, thermal, or other energy.

Hot tap. A procedure used in the repair, maintenance,and services activities, which involve welding on a piece ofequipment (pipelines, vessels, or tanks) under pressure, in orderto install connections or appurtenances. It is commonly used

Commonly Used Terms

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21Commonly Used Terms

to replace or add sections of pipeline without the interruptionof service for air, gas, water, steam, and petrochemicaldistribution systems.

Lockout. The placement of a lockout device on anenergy-isolating device, in accordance with an establishedprocedure, ensuring that the energy-isolating device and theequipment being controlled cannot be operated until thelockout device is removed.

Lockout device. A device that uses a positive means suchas a lock, either key or combination type, to hold an energy-isolating device in the safe position and prevent the energizingof a machine or equipment. Included are blank flanges andbolted slip blinds.

Normal production operations. The utilization of a machineor equipment to perform its intended production function.

Servicing and/or maintenance. Workplace activities suchas constructing, installing, setting up, adjusting, inspecting,modifying, and maintaining and/or servicing machines orequipment. These activities include lubricating, cleaning orunjamming machines or equipment and making adjustmentsor tool changes where the employee may be exposed to theunexpected energization or startup of the equipment or releaseof hazardous energy.

Setting up. Any work performed to prepare a machine orequipment to perform its normal production operation.

Tagout. The placement of a tagout device on an energy-isolating device, in accordance with an established procedure,to indicate that the energy-isolating device and the equipmentbeing controlled may not be operated until the tagout deviceis removed.

Tagout device. A prominent warning device, such as a tagand a means of attachment, which can be securely fastened toan energy-isolating device in accordance with an establishedprocedure, to indicate that the energy-isolating device andthe equipment being controlled may not be operated until thetagout device is removed.

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The control of hazardous energy (lockout/tagout). - 1910.147



• Subpart: J

• Subpart Title: General Environmental Controls


• Title: The control of hazardous energy (lockout/tagout).

• Appendix: A

1910.147(a)

Scope, application and purpose -

1910.147(a)(1)

Scope

1910.147(a)(1)(i)

This standard covers the servicing and maintenance of machines and equipment in which

the unexpected energization or start up of the machines or equipment, or release of

stored energy could cause injury to employees. This standard establishes minimum

performance requirements for the control of such hazardous energy.

1910.147(a)(1)(ii)

This standard does not cover the following:

1910.147(a)(1)(ii)(A)

Construction, agriculture and maritime employment;

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1910.147(a)(1)(ii)(B)

Installations under the exclusive control of electric utilities for the purpose of power

generation, transmission and distribution, including related equipment for communication

or metering; and

1910.147(a)(1)(ii)(C)

Exposure to electrical hazards from work on, near, or with conductors or equipment in

electric utilization installations, which is covered by Subpart S of this part; and

..1910.147(a)(1)(ii)(D)

1910.147(a)(1)(ii)(D)

Oil and gas well drilling and servicing.

1910.147(a)(2)

Application.

1910.147(a)(2)(i)

This standard applies to the control of energy during servicing and/or maintenance of

machines and equipment.

1910.147(a)(2)(ii)

Normal production operations are not covered by this standard (See Subpart O of this

Part). Servicing and/or maintenance which takes place during normal production

operations is covered by this standard only if:

1910.147(a)(2)(ii)(A)

An employee is required to remove or bypass a guard or other safety device; or

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1910.147(a)(2)(ii)(B)

An employee is required to place any part of his or her body into an area on a machine or

piece of equipment where work is actually performed upon the material being processed

(point of operation) or where an associated danger zone exists during a machine

operating cycle.

Note: Exception to paragraph (a)(2)(ii): Minor tool changes and adjustments, and other

minor servicing activities, which take place during normal production operations, are not

covered by this standard if they are routine, repetitive, and integral to the use of the

equipment for production, provided that the work is performed using alternative measures

which provide effective protection (See Subpart O of this Part).

1910.147(a)(2)(iii)

This standard does not apply to the following:

..1910.147(a)(2)(iii)(A)

1910.147(a)(2)(iii)(A)

Work on cord and plug connected electric equipment for which exposure to the hazards

of unexpected energization or start up of the equipment is controlled by the unplugging of

the equipment from the energy source and by the plug being under the exclusive control

of the employee performing the servicing or maintenance.

1910.147(a)(2)(iii)(B)

Hot tap operations involving transmission and distribution systems for substances such as

gas, steam, water or petroleum products when they are performed on pressurized

pipelines, provided that the employer demonstrates that-

1910.147(a)(2)(iii)(B)(1)

continuity of service is essential;

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1910.147(a)(2)(iii)(B)(2)

shutdown of the system is impractical; and

1910.147(a)(2)(iii)(B)(3)

documented procedures are followed, and special equipment is used which will provide

proven effective protection for employees.

1910.147(a)(3)

Purpose.

1910.147(a)(3)(i)

This section requires employers to establish a program and utilize procedures for affixing

appropriate lockout devices or tagout devices to energy isolating devices, and to

otherwise disable machines or equipment to prevent unexpected energization, start up or

release of stored energy in order to prevent injury to employees.

1910.147(a)(3)(ii)

When other standards in this part require the use of lockout or tagout, they shall be used

and supplemented by the procedural and training requirements of this section.

1910.147(b)

Definitions applicable to this section.

Affected employee. An employee whose job requires him/her to operate or use a

machine or equipment on which servicing or maintenance is being performed under

lockout or tagout, or whose job requires him/her to work in an area in which such

servicing or maintenance is being performed.

Authorized employee. A person who locks out or tags out machines or equipment in

order to perform servicing or maintenance on that machine or equipment. An affected

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employee becomes an authorized employee when that employee's duties include

performing servicing or maintenance covered under this section.

Capable of being locked out. An energy isolating device is capable of being locked out

if it has a hasp or other means of attachment to which, or through which, a lock can be

affixed, or it has a locking mechanism built into it. Other energy isolating devices are

capable of being locked out, if lockout can be achieved without the need to dismantle,

rebuild, or replace the energy isolating device or permanently alter its energy control

capability.

Energized. Connected to an energy source or containing residual or stored energy.

Energy isolating device. A mechanical device that physically prevents the transmission

or release of energy, including but not limited to the following: A manually operated

electrical circuit breaker; a disconnect switch; a manually operated switch by which the

conductors of a circuit can be disconnected from all ungrounded supply conductors, and,

in addition, no pole can be operated independently; a line valve; a block; and any similar

device used to block or isolate energy. Push buttons, selector switches and other control

circuit type devices are not energy isolating devices.

Energy source. Any source of electrical, mechanical, hydraulic, pneumatic, chemical,

thermal, or other energy.

Hot tap. A procedure used in the repair, maintenance and services activities which

involves welding on a piece of equipment (pipelines, vessels or tanks) under pressure, in

order to install connections or appurtenances. it is commonly used to replace or add

sections of pipeline without the interruption of service for air, gas, water, steam, and

petrochemical distribution systems.

Lockout. The placement of a lockout device on an energy isolating device, in accordance

with an established procedure, ensuring that the energy isolating device and the

equipment being controlled cannot be operated until the lockout device is removed.

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Lockout device. A device that utilizes a positive means such as a lock, either key or

combination type, to hold an energy isolating device in the safe position and prevent the

energizing of a machine or equipment. Included are blank flanges and bolted slip blinds.

Normal production operations. The utilization of a machine or equipment to perform

its intended production function.

Servicing and/or maintenance. Workplace activities such as constructing, installing,

setting up, adjusting, inspecting, modifying, and maintaining and/or servicing machines

or equipment. These activities include lubrication, cleaning or unjamming of machines or

equipment and making adjustments or tool changes, where the employee may be exposed

to the unexpected energization or startup of the equipment or release of hazardous

energy.

Setting up. Any work performed to prepare a machine or equipment to perform its

normal production operation.

Tagout. The placement of a tagout device on an energy isolating device, in accordance

with an established procedure, to indicate that the energy isolating device and the

equipment being controlled may not be operated until the tagout device is removed.

Tagout device. A prominent warning device, such as a tag and a means of attachment,

which can be securely fastened to an energy isolating device in accordance with an

established procedure, to indicate that the energy isolating device and the equipment

being controlled may not be operated until the tagout device is removed.

..1910.147(c)

1910.147(c)

General -

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1910.147(c)(1)

Energy control program. The employer shall establish a program consisting of energy

control procedures, employee training and periodic inspections to ensure that before any

employee performs any servicing or maintenance on a machine or equipment where the

unexpected energizing, startup or release of stored energy could occur and cause injury,

the machine or equipment shall be isolated from the energy source and rendered

inoperative.

1910.147(c)(2)

Lockout/tagout.

1910.147(c)(2)(i)

If an energy isolating device is not capable of being locked out, the employer's energy

control program under paragraph (c)(1) of this section shall utilize a tagout system.

1910.147(c)(2)(ii)

If an energy isolating device is capable of being locked out, the employer's energy control

program under paragraph (c)(1) of this section shall utilize lockout, unless the employer

can demonstrate that the utilization of a tagout system will provide full employee

protection as set forth in paragraph (c)(3) of this section.

1910.147(c)(2)(iii)

After January 2, 1990, whenever replacement or major repair, renovation or modification

of a machine or equipment is performed, and whenever new machines or equipment are

installed, energy isolating devices for such machine or equipment shall be designed to

accept a lockout device.

1910.147(c)(3)

Full employee protection.

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1910.147(c)(3)(i)

When a tagout device is used on an energy isolating device which is capable of being

locked out, the tagout device shall be attached at the same location that the lockout device

would have been attached, and the employer shall demonstrate that the tagout program

will provide a level of safety equivalent to that obtained by using a lockout program.

..1910.147(c)(3)(ii)

1910.147(c)(3)(ii)

In demonstrating that a level of safety is achieved in the tagout program which is

equivalent to the level of safety obtained by using a lockout program, the employer shall

demonstrate full compliance with all tagout-related provisions of this standard together

with such additional elements as are necessary to provide the equivalent safety available

from the use of a lockout device. Additional means to be considered as part of the

demonstration of full employee protection shall include the implementation of additional

safety measures such as the removal of an isolating circuit element, blocking of a

controlling switch, opening of an extra disconnecting device, or the removal of a valve

handle to reduce the likelihood of inadvertent energization.

1910.147(c)(4)

Energy control procedure.

1910.147(c)(4)(i)

Procedures shall be developed, documented and utilized for the control of potentially

hazardous energy when employees are engaged in the activities covered by this section.

Note: Exception: The employer need not document the required procedure for a

particular machine or equipment, when all of the following elements exist: (1) The

machine or equipment has no potential for stored or residual energy or reaccumulation of

stored energy after shut down which could endanger employees; (2) the machine or

equipment has a single energy source which can be readily identified and isolated; (3) the

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isolation and locking out of that energy source will completely deenergize and deactivate

the machine or equipment; (4) the machine or equipment is isolated from that energy

source and locked out during servicing or maintenance; (5) a single lockout device will

achieve a locker-out condition; (6) the lockout device is under the exclusive control of the

authorized employee performing the servicing or maintenance; (7) the servicing or

maintenance does not create hazards for other employees; and (8) the employer, in

utilizing this exception, has had no accidents involving the unexpected activation or

reenergization of the machine or equipment during servicing or maintenance.

1910.147(c)(4)(ii)

The procedures shall clearly and specifically outline the scope, purpose, authorization,

rules, and techniques to be utilized for the control of hazardous energy, and the means to

enforce compliance including, but not limited to, the following:

1910.147(c)(4)(ii)(A)

A specific statement of the intended use of the procedure;

1910.147(c)(4)(ii)(B)

Specific procedural steps for shutting down, isolating, blocking and securing machines or

equipment to control hazardous energy;

1910.147(c)(4)(ii)(C)

Specific procedural steps for the placement, removal and transfer of lockout devices or

tagout devices and the responsibility for them; and

..1910.147(c)(4)(ii)(D)

1910.147(c)(4)(ii)(D)

Specific requirements for testing a machine or equipment to determine and verify the

effectiveness of lockout devices, tagout devices, and other energy control measures.

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1910.147(c)(5)

Protective materials and hardware.

1910.147(c)(5)(i)

Locks, tags, chains, wedges, key blocks, adapter pins, self-locking fasteners, or other

hardware shall be provided by the employer for isolating, securing or blocking of

machines or equipment from energy sources.

1910.147(c)(5)(ii)

Lockout devices and tagout devices shall be singularly identified; shall be the only

devices(s) used for controlling energy; shall not be used for other purposes; and shall

meet the following requirements:

1910.147(c)(5)(ii)(A)

Durable.

1910.147(c)(5)(ii)(A)(1)

Lockout and tagout devices shall be capable of withstanding the environment to which

they are exposed for the maximum period of time that exposure is expected.

1910.147(c)(5)(ii)(A)(2)

Tagout devices shall be constructed and printed so that exposure to weather conditions or

wet and damp locations will not cause the tag to deteriorate or the message on the tag to

become illegible.

1910.147(c)(5)(ii)(A)(3)

Tags shall not deteriorate when used in corrosive environments such as areas where acid

and alkali chemicals are handled and stored.

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1910.147(c)(5)(ii)(B)

Standardized. Lockout and tagout devices shall be standardized within the facility in at

least one of the following criteria: Color; shape; or size; and additionally, in the case of

tagout devices, print and format shall be standardized.

1910.147(c)(5)(ii)(C)

Substantial -

1910.147(c)(5)(ii)(C)(1)

Lockout devices. Lockout devices shall be substantial enough to prevent removal

without the use of excessive force or unusual techniques, such as with the use of bolt

cutters or other metal cutting tools.

1910.147(c)(5)(ii)(C)(2)

Tagout devices. Tagout devices, including their means of attachment, shall be substantial

enough to prevent inadvertent or accidental removal. Tagout device attachment means

shall be of a non-reusable type, attachable by hand, self-locking, and non-releasable with

a minimum unlocking strength of no less than 50 pounds and having the general design

and basic characteristics of being at least equivalent to a one-piece, all environment-

tolerant nylon cable tie.

1910.147(c)(5)(ii)(D)

Identifiable. Lockout devices and tagout devices shall indicate the identity of the

employee applying the device(s).

1910.147(c)(5)(iii)

Tagout devices shall warn against hazardous conditions if the machine or equipment is

energized and shall include a legend such as the following: Do Not Start. Do Not Open.

Do Not Close. Do Not Energize. Do Not Operate.

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1910.147(c)(6)

Periodic inspection.

1910.147(c)(6)(i)

The employer shall conduct a periodic inspection of the energy control procedure at least

annually to ensure that the procedure and the requirements of this standard are being

followed.

1910.147(c)(6)(i)(A)

The periodic inspection shall be performed by an authorized employee other than the

ones(s) utilizing the energy control procedure being inspected.

1910.147(c)(6)(i)(B)

The periodic inspection shall be conducted to correct any deviations or inadequacies

identified.

1910.147(c)(6)(i)(C)

Where lockout is used for energy control, the periodic inspection shall include a review,

between the inspector and each authorized employee, of that employee's responsibilities

under the energy control procedure being inspected.

1910.147(c)(6)(i)(D)

Where tagout is used for energy control, the periodic inspection shall include a review,

between the inspector and each authorized and affected employee, of that employee's

responsibilities under the energy control procedure being inspected, and the elements set

forth in paragraph (c)(7)(ii) of this section.

..1910.147(c)(6)(ii)

The employer shall certify that the periodic inspections have been performed. The

certification shall identify the machine or equipment on which the energy control

264

procedure was being utilized, the date of the inspection, the employees included in the

inspection, and the person performing the inspection.

1910.147(c)(7)

Training and communication.

1910.147(c)(7)(i)

The employer shall provide training to ensure that the purpose and function of the energy

control program are understood by employees and that the knowledge and skills required

for the safe application, usage, and removal of the energy controls are acquired by

employees. The training shall include the following:

1910.147(c)(7)(i)(A)

Each authorized employee shall receive training in the recognition of applicable

hazardous energy sources, the type and magnitude of the energy available in the

workplace, and the methods and means necessary for energy isolation and control.

1910.147(c)(7)(i)(B)

Each affected employee shall be instructed in the purpose and use of the energy control

procedure.

1910.147(c)(7)(i)(C)

All other employees whose work operations are or may be in an area where energy

control procedures may be utilized, shall be instructed about the procedure, and about the

prohibition relating to attempts to restart or reenergize machines or equipment which are

locked out or tagged out.

1910.147(c)(7)(ii)

When tagout systems are used, employees shall also be trained in the following

limitations of tags:

265

1910.147(c)(7)(ii)(A)

Tags are essentially warning devices affixed to energy isolating devices, and do not

provide the physical restraint on those devices that is provided by a lock.

1910.147(c)(7)(ii)(B)

When a tag is attached to an energy isolating means, it is not to be removed without

authorization of the authorized person responsible for it, and it is never to be bypassed,

ignored, or otherwise defeated.

1910.147(c)(7)(ii)(C)

Tags must be legible and understandable by all authorized employees, affected

employees, and all other employees whose work operations are or may be in the area, in

order to be effective.

1910.147(c)(7)(ii)(D)

Tags and their means of attachment must be made of materials which will withstand the

environmental conditions encountered in the workplace.

1910.147(c)(7)(ii)(E)

Tags may evoke a false sense of security, and their meaning needs to be understood as

part of the overall energy control program.

1910.147(c)(7)(ii)(F)

Tags must be securely attached to energy isolating devices so that they cannot be

inadvertently or accidentally detached during use.

1910.147(c)(7)(iii)

Employee retraining.

266

1910.147(c)(7)(iii)(A)

Retraining shall be provided for all authorized and affected employees whenever there is

a change in their job assignments, a change in machines, equipment or processes that

present a new hazard, or when there is a change in the energy control procedures.

1910.147(c)(7)(iii)(B)

Additional retraining shall also be conducted whenever a periodic inspection under

paragraph (c)(6) of this section reveals, or whenever the employer has reason to believe

that there are deviations from or inadequacies in the employee's knowledge or use of the

energy control procedures.

1910.147(c)(7)(iii)(C)

The retraining shall reestablish employee proficiency and introduce new or revised

control methods and procedures, as necessary.

1910.147(c)(7)(iv)

The employer shall certify that employee training has been accomplished and is being

kept up to date. The certification shall contain each employee's name and dates of

training.

1910.147(c)(8)

Energy isolation. Lockout or tagout shall be performed only by the authorized

employees who are performing the servicing or maintenance.

1910.147(c)(9)

Notification of employees. Affected employees shall be notified by the employer or

authorized employee of the application and removal of lockout devices or tagout devices.

Notification shall be given before the controls are applied, and after they are removed

from the machine or equipment.

267

1910.147(d)

Application of control. The established procedures for the application of energy control

(the lockout or tagout procedures) shall cover the following elements and actions and

shall be done in the following sequence:

1910.147(d)(1)

Preparation for shutdown. Before an authorized or affected employee turns off a

machine or equipment, the authorized employee shall have knowledge of the type and

magnitude of the energy, the hazards of the energy to be controlled, and the method or

means to control the energy.

1910.147(d)(2)

Machine or equipment shutdown. The machine or equipment shall be turned off or shut

down using the procedures established for the machine or equipment. An orderly

shutdown must be utilized to avoid any additional or increased hazard(s) to employees as

a result of the equipment stoppage.

1910.147(d)(3)

Machine or equipment isolation. All energy isolating devices that are needed to control

the energy to the machine or equipment shall be physically located and operated in such a

manner as to isolate the machine or equipment from the energy source(s).

1910.147(d)(4)

Lockout or tagout device application.

1910.147(d)(4)(i)

Lockout or tagout devices shall be affixed to each energy isolating device by authorized

employees.

268

1910.147(d)(4)(ii)

Lockout devices, where used, shall be affixed in a manner to that will hold the energy

isolating devices in a "safe" or "off" position.

1910.147(d)(4)(iii)

Tagout devices, where used, shall be affixed in such a manner as will clearly indicate that

the operation or movement of energy isolating devices from the "safe" or "off" position is

prohibited.

1910.147(d)(4)(iii)(A)

Where tagout devices are used with energy isolating devices designed with the capability

of being locked, the tag attachment shall be fastened at the same point at which the lock

would have been attached.

1910.147(d)(4)(iii)(B)

Where a tag cannot be affixed directly to the energy isolating device, the tag shall be

located as close as safely possible to the device, in a position that will be immediately

obvious to anyone attempting to operate the device.

1910.147(d)(5)

Stored energy.

1910.147(d)(5)(i)

Following the application of lockout or tagout devices to energy isolating devices, all

potentially hazardous stored or residual energy shall be relieved, disconnected, restrained,

and otherwise rendered safe.

269

1910.147(d)(5)(ii)

If there is a possibility of reaccumulation of stored energy to a hazardous level,

verification of isolation shall be continued until the servicing or maintenance is

completed, or until the possibility of such accumulation no longer exists.

1910.147(d)(6)

Verification of isolation. Prior to starting work on machines or equipment that have been

locked out or tagged out, the authorized employee shall verify that isolation and

deenergization of the machine or equipment have been accomplished.

1910.147(e)

Release from lockout or tagout. Before lockout or tagout devices are removed and

energy is restored to the machine or equipment, procedures shall be followed and actions

taken by the authorized employee(s) to ensure the following:

1910.147(e)(1)

The machine or equipment. The work area shall be inspected to ensure that nonessential

items have been removed and to ensure that machine or equipment components are

operationally intact.

1910.147(e)(2)

Employees.

1910.147(e)(2)(i)

The work area shall be checked to ensure that all employees have been safely positioned

or removed.

270

1910.147(e)(2)(ii)

After lockout or tagout devices have been removed and before a machine or equipment is

started, affected employees shall be notified that the lockout or tagout device(s) have

been removed.

1910.147(e)(3)

Lockout or tagout devices removal. Each lockout or tagout device shall be removed

from each energy isolating device by the employee who applied the device. Exception to

paragraph (e)(3): When the authorized employee who applied the lockout or tagout

device is not available to remove it, that device may be removed under the direction of

the employer, provided that specific procedures and training for such removal have been

developed, documented and incorporated into the employer's energy control program.

The employer shall demonstrate that the specific procedure provides equivalent safety to

the removal of the device by the authorized employee who applied it. The specific

procedure shall include at least the following elements:

1910.147(e)(3)(i)

Verification by the employer that the authorized employee who applied the device is not

at the facility:

1910.147(e)(3)(ii)

Making all reasonable efforts to contact the authorized employee to inform him/her that

his/her lockout or tagout device has been removed; and

1910.147(e)(3)(iii)

Ensuring that the authorized employee has this knowledge before he/she resumes work at

that facility.

1910.147(f)

Additional requirements.

271

1910.147(f)(1)

Testing or positioning of machines, equipment or components thereof. In situations

in which lockout or tagout devices must be temporarily removed from the energy

isolating device and the machine or equipment energized to test or position the machine,

equipment or component thereof, the following sequence of actions shall be followed:

1910.147(f)(1)(i)

Clear the machine or equipment of tools and materials in accordance with paragraph

(e)(1) of this section;

1910.147(f)(1)(ii)

Remove employees from the machine or equipment area in accordance with paragraph

(e)(2) of this section;

1910.147(f)(1)(iii)

Remove the lockout or tagout devices as specified in paragraph (e)(3) of this section;

1910.147(f)(1)(iv)

Energize and proceed with testing or positioning;

1910.147(f)(1)(v)

Deenergize all systems and reapply energy control measures in accordance with

paragraph (d) of this section to continue the servicing and/or maintenance.

1910.147(f)(2)

Outside personnel (contractors, etc.).

272

1910.147(f)(2)(i)

Whenever outside servicing personnel are to be engaged in activities covered by the

scope and application of this standard, the on-site employer and the outside employer

shall inform each other of their respective lockout or tagout procedures.

1910.147(f)(2)(ii)

The on-site employer shall ensure that his/her employees understand and comply with the

restrictions and prohibitions of the outside employer's energy control program.

1910.147(f)(3)

Group lockout or tagout.

1910.147(f)(3)(i)

When servicing and/or maintenance is performed by a crew, craft, department or other

group, they shall utilize a procedure which affords the employees a level of protection

equivalent to that provided by the implementation of a personal lockout or tagout device.

1910.147(f)(3)(ii)

Group lockout or tagout devices shall be used in accordance with the procedures required

by paragraph (c)(4) of this section including, but not necessarily limited to, the following

specific requirements:

1910.147(f)(3)(ii)(A)

Primary responsibility is vested in an authorized employee for a set number of employees

working under the protection of a group lockout or tagout device (such as an operations

lock);

1910.147(f)(3)(ii)(B)

Provision for the authorized employee to ascertain the exposure status of individual group

members with regard to the lockout or tagout of the machine or equipment and

273

1910.147(f)(3)(ii)(C)

When more than one crew, craft, department, etc. is involved, assignment of overall job-

associated lockout or tagout control responsibility to an authorized employee designated

to coordinate affected work forces and ensure continuity of protection; and

1910.147(f)(3)(ii)(D)

Each authorized employee shall affix a personal lockout or tagout device to the group

lockout device, group lockbox, or comparable mechanism when he or she begins work,

and shall remove those devices when he or she stops working on the machine or

equipment being serviced or maintained.

1910.147(f)(4)

Shift or personnel changes. Specific procedures shall be utilized during shift or

personnel changes to ensure the continuity of lockout or tagout protection, including

provision for the orderly transfer of lockout or tagout device protection between off-

going and oncoming employees, to minimize exposure to hazards from the unexpected

energization or start-up of the machine or equipment, or the release of stored energy.

Note: The following appendix to §1910.147 services as a non-mandatory guideline to

assist employers and employees in complying with the requirements of this section, as

well as to provide other helpful information. Nothing in the appendix adds to or detracts

from any of the requirements of this section.

[54 FR 36687, Sept. 1, 1989, as amended at 54 FR 42498, Oct. 17, 1989; 55 FR 38685,

38686, Sept. 20, 1990; 61 FR 5507, Feb. 13, 1996]

274


Typical minimal lockout procedures - 1910.147 App A



• Subpart: J

• Subpart Title: General Environmental Controls

• Standard Number: 1910.147 App A

• Title: Typical minimal lockout procedures

General

The following simple lockout procedure is provided to assist employers in developing

their procedures so they meet the requirements of this standard. When the energy

isolating devices are not lockable, tagout may be used, provided the employer complies

with the provisions of the standard which require additional training and more rigorous

periodic inspections. When tagout is used and the energy isolating devices are lockable,

the employer must provide full employee protection (see paragraph (c)(3)) and additional

training and more rigorous periodic inspections are required. For more complex systems,

more comprehensive procedures may need to be developed, documented, and utilized.

Lockout Procedure

Lockout Procedure for

_____________________________________________________________________

(Name of Company for single procedure or identification of equipment

if multiple procedures are used).

275

Purpose

This procedure establishes the minimum requirements for the lockout of energy isolating

devices whenever maintenance or servicing is done on machines or equipment. It shall be

used to ensure that the machine or equipment is stopped, isolated from all potentially

hazardous energy sources and locked out before employees perform any servicing or

maintenance where the unexpected energization or start-up of the machine or equipment

or release of stored energy could cause injury.

Compliance With This Program

All employees are required to comply with the restrictions and limitations imposed upon

them during the use of lockout. The authorized employees are required to perform the

lockout in accordance with this procedure. All employees, upon observing a machine or

piece of equipment which is locked out to perform servicing or maintenance shall not

attempt to start, energize, or use that machine or equipment.

_____________________________________________________________________

Type of compliance enforcement to be taken for violation of the above.

Sequence of Lockout

(1) Notify all affected employees that servicing or maintenance is required on a machine

or equipment and that the machine or equipment must be shut down and locked out to

perform the servicing or maintenance.

___________________________________________________________________

276

Name(s)/Job Title(s) of affected employees and how to notify.

(2) The authorized employee shall refer to the company procedure to identify the type

and magnitude of the energy that the machine or equipment utilizes, shall understand the

hazards of the energy, and shall know the methods to control the energy.

_____________________________________________________________________

Type(s) and magnitude(s) of energy, its hazards and the methods to

control the energy.

(3) If the machine or equipment is operating, shut it down by the normal stopping

procedure (depress the stop button, open switch, close valve, etc.).

_____________________________________________________________________

Type(s) and location(s) of machine or equipment operating controls.

(4) De-activate the energy isolating device(s) so that the machine or equipment is isolated

from the energy source(s).

_____________________________________________________________________

Type(s) and location(s) of energy isolating devices.

(5) Lock out the energy isolating device(s) with assigned individual lock(s).

(6) Stored or residual energy (such as that in capacitors, springs, elevated machine

members, rotating flywheels, hydraulic systems, and air, gas, steam, or water pressure,

277

etc.) must be dissipated or restrained by methods such as grounding, repositioning,

blocking, bleeding down, etc.

_____________________________________________________________________

Type(s) of stored energy - methods to dissipate or restrain.

(7) Ensure that the equipment is disconnected from the energy source(s) by first checking

that no personnel are exposed, then verify the isolation of the equipment by operating the

push button or other normal operating control(s) or by testing to make certain the

equipment will not operate.

Caution: Return operating control(s) to neutral or "off" position after verifying the

isolation of the equipment.

_____________________________________________________________________

Method of verifying the isolation of the equipment.

(8) The machine or equipment is now locked out.

"Restoring Equipment to Service." When the servicing or maintenance is completed and

the machine or equipment is ready to return to normal operating condition, the following

steps shall be taken.

(1) Check the machine or equipment and the immediate area around the machine to

ensure that nonessential items have been removed and that the machine or equipment

components are operationally intact.

(2) Check the work area to ensure that all employees have been safely positioned or

removed from the area.

278

(3) Verify that the controls are in neutral.

(4) Remove the lockout devices and reenergize the machine or equipment. Note: The

removal of some forms of blocking may require reenergization of of the machine before

safe removal.

(5) Notify affected employees that the servicing or maintenance is completed and the

machine or equipment is ready for used.

[54 FR 36687, Sept. 1, 1989 as amended at 54 FR 42498, Oct. 17, 1989; 55 FR 38685,

Sept. 20, 1990; 61 FR 5507, Feb. 13, 1996]

279

280

Standard Interpretations

12/21/1999 - Grounding requirements for equipment

connected by cord and plug.

• Standard Number: 1910.304(f)(5)(v) ; 1910.304(a)(3)

December 21, 1999

MEMORANDUM FOR: CINDY COE, ACTING REGIONAL ADMINISTRATOR

ATLANTA REGIONAL OFFICE

ATTENTION:

BENJAMIN ROSS, ASSISTANT REGIONAL

ADMINISTRATOR

FOR TECHNICAL SUPPORT

LUIS R. SANTIAGO, AREA DIRECTOR

SAVANNAH AREA OFFICE

FROM: RICHARD E. FAIRFAX, DIRECTOR

DIRECTORATE OF COMPLIANCE PROGRAMS

SUBJECT: INTERPRETATION OF ELECTRICAL STANDARDS

Thank you for your December 2, 1999 memorandum requesting an interpretation on the

electrical grounding requirements for a nursing home. Your scenario, questions, and our

reply follow.

Scenario: A nursing home was cited under the Electrical Standards, 29 CFR

§1910.304(f)(5)(v) requirements for the failure to provide a ground for equipment (i.e.,

refrigerators; microwaves ovens; water fountains) connected by cord and plug. The building

was built circa 1958, had a two wire electrical system, and, according to the employer, had

not been altered or remodeled. The receptacle boxes had receptacles that would accept a

three-wire attachment plug and the employer used the receptacles to power grounding-type

equipment. The employer is not disputing the merits of the electrical grounding citation.

However, he wishes to install ground fault circuit interrupters (GFCI) to abate the electrical

shock hazard in lieu of expensive system grounding rewiring.

281

Question #1: Is it acceptable to install GFCI protection instead of rewiring the facility with

an electrical grounding conductor system?

Reply: The answer to your question, with respect to the cord- and plug-connected equipment

that requires grounding, is "No." (1)

The described existing condition at the nursing home was

properly cited as the grounding type receptacles, which replaced the previous nongrounding-

type receptacles, were only permitted to be installed if a grounding means existed in the

receptacle enclosure. The equipment grounding conductor grounds the noncurrent-carrying,

metal parts of tools or equipment and carries off the leakage current thus limiting the voltage

on the tool or equipment frame by providing a low resistance path to ground. When the

leakage current increases beyond the setting of the over-current device protecting the circuit

(usually 15 or 20 amperes), the device trips and interrupts the current.

The ground-fault circuit interrupter, on the other hand, is a fast-acting device which senses

small current leakage to ground and, in a fraction of a second, shuts off the electricity and

interrupts its faulty flow to ground. The rapid response of the GFCI is fast enough to prevent

electrocution and this protection is independent of the condition of the grounding conductor.

A GFCI can prevent an electrocution; however, it cannot by itself prevent an initial electric

shock to an employee before it interrupts the circuit. This initial shock could lead to injuries

of an indirect or secondary nature in which involuntary muscular reaction could cause

bruises, bone fractures, and even death resulting from collisions or falls. Therefore, GFCIs

are in addition to, and not in lieu of, equipment grounding conductor requirements.

In A.L. Baumgartner Construction, Inc., 16 BNA OSHC 1995 (No. 92-1022, 1994), the

Review Commission affirmed a decision by an Administrative Law Judge regarding GFCI

protection and a damaged power cord. The Commission held that the violation was "serious"

since the employees were also exposed to a fall hazard and a slight shock may cause them to

fall and sustain serious injuries. Even though the GFCI is designed to protect against

electrocution, the Commission ruled other hazards exist due to the involuntary muscular

contractions which may cause a startled employee reaction to the shock.

282

OSHA is not allowing the use of a GFCI alone to protect employees using cord and plug

connected equipment when such equipment is required to be grounded. Paragraph

1910.304(f)(5)(v)(a) through (c), describes the types of cord and plug connected equipment,

such as refrigerators and microwave ovens, that is required to be grounded with an

equipment grounding conductor.

Question #2: The company contacted a member of the National Electrical Code (NEC)

Committee and they were told, that according to the 1999 code, it was acceptable to use a

GFCI instead of a grounding wire. Is this interpretation correct and would it be considered

compliant to meet this NEC provision in lieu of §1910.304(f)(5)(v)?

Reply: The company interpretation is incorrect. The equipment grounding requirements for

cord and plug connected equipment, contained in Section 250-114 of the 1999 NEC, does not

provide an exception that permits the use of a GFCI in lieu of equipment grounding. The

GFCI provisions, contained in Section 210-7(d), pertain to the requirements for receptacle

replacement and not to the grounding of equipment. (2)

The use of a GFCI-type receptacle or GFCI-type circuit breaker in lieu of an equipment

grounding conductor run to the receptacle outlet is permitted by the 1999 NEC, Section 210-

7, on branch circuits. However, all of the listed conditions must be met to meet this code

exception. Section 210-7(d)(3) contains additional marking and wiring requirements that

must be met when GFCI-type receptacle(s) or circuit breaker(s) are used when a grounding

means is not available. Strict compliance with these NEC requirements would constitute a de

minimis violation of OSHA electrical standard §1910.304(a)(3) as the GFCI-type receptacles

would provide additional personnel protection and would not be used in lieu of equipment

grounding.

For example, if a GFCI-type receptacle is used, it must be visibly marked "No Equipment

Ground," and equipment required to be grounded may not be used in the ungrounded, GFCI-

type receptacle. However, many appliances (i.e., lamps; toasters; televisions; double

insulated appliances) and tools (i.e., double insulated tools; tools supplied with a low voltage

isolating transformer) are not required to be grounded and they may be used in an

283

ungrounded, GFCI-type receptacle. The GFCI feature of these GFCI-type receptacles

provides additional electrocution protection in the event of misuse (i.e., a floor buffing

machine is powered by a 3-prong plug from a properly marked and wired ungrounded,

GFCI-type receptacle).

We hope you find this information helpful. If you have any further questions, please feel free

to contact the Office of General Industry Compliance Assistance at (202) 693-1850.

FOOTNOTE (1)The §1910.304(f)(5)(v) grounding provisions were contained in the former

§1910.309(a) which incorporated by reference Section 250-45(a) through (d) of the 1971

National Electrical Code. Therefore, all general industry employers have been required to be

in compliance with these "retroactive" grounding requirements since March 15, 1972.

Additionally, OSHA considered the issue, during the Electrical Standards rulemaking

process (Federal Register, 46(11), Friday, January 16, 1981, p. 4043), of whether to change

the existing §1910.309(a) application paragraph. It was decided that these application

"retroactive" provisions were reasonably necessary for employee safety and had not been

shown to be an unwarranted or extreme cost burden on employers.

FOOTNOTE (2)Also, the provisions of Article 517 of the 1999 NEC apply to electrical

construction and installation criteria and are nevertheless intended to apply in a very specific

manner. Part B of this Section applies to the patient care areas of the health care facility and

section 517-13 covers the grounding of receptacles and fixed electrical equipment. It should

be clearly understood that Section 517-13(a) requires (with three exceptions) grounding by

means of an insulated copper conductor installed with the branch-circuit conductors.

284


03/31/2004 - Fixed Wiring in Research Facilities and High

Voltage Cable Tray Systems at Department of Energy (DOE) Research Laboratories

• Standard Number: 1910.305(a); 1910.305(a)(2); 1910.305(a)(2)(iii)(B) ;

1910.305(a)(3); 1910.305(b); 1910.305(g)(1);

1910.305(g)(1)(i); 1910.305(g)(1)(iii); 1910.399

March 31, 2004

MEMORANDUM FOR: RUTH MCCULLY

Director, Directorate of Science, Technology, and Medicine

FROM: RICHARD E. FAIRFAX, CIH, DIRECTOR

DIRECTORATE OF ENFORCEMENT PROGRAMS

SUBJECT: Fixed Wiring in Research Facilities and High-Voltage Cable Tray

Systems at Department of Energy (DOE) Research Laboratories

Thank you for your March 4, 2004 memorandum regarding the compliance audits at the DOE

research laboratories and our Electrical, Subpart S, standards contained in 29 CFR Part 1910.

Your paraphrased questions and our replies follow:

Question 1: Six of the research laboratories have accelerators, which have substantial electrical

requirements and are used for physics research. At times, when the accelerator is shut down,

some of the wiring must be moved or changed; but wiring often may be in place for years. Also,

with respect to other large research equipment, such as particle detectors, there are a large

number of devices that are not hard-wired and instead use flexible cords equipped with

attachment plugs. Typically, the equipment is upgraded to seek continually higher levels of

performance, or, in some cases, items are inserted, tested, modified, removed, re-modified,

reinstalled, etc. This occurs during downtime periods, where the accelerator is brought down

and new equipment is installed. This may be over a period of months or years.

285

Your Directorate's October 12, 1995 interpretation letter, regarding flexible cord use for

research projects, to the Department of Navy was reviewed, and it does not appear to address

our situation.1

The impact of OSHA requiring fixed (permanent) wiring will have substantial financial

implications for the DOE laboratories. What is the length of time or the criteria to determine

when fixed (permanent) wiring is required in lieu of flexible wiring?

Reply: Both permanent wiring and temporary wiring may be either fixed (that is, fastened in

place) or moveable (that is, connected by flexible cords or cables). Because your scenario

involves the use of flexible cords, we explain when flexible cords or cables are permitted as a

temporary wiring method and when they are permitted with permanent wiring.

29 CFR §1910.305(a)(2)(iii)(B) requires temporary branch circuits to be run as multiconductor

cord or cable assemblies or as open conductors. Thus, flexible cords and cables are permitted to

be used as branch circuit conductors whenever temporary wiring is permitted and is actually

being used. The Temporary wiring requirements, which are contained in §1910.305(a)(2), lists

permitted uses for temporary wiring, permits temporary wiring of 600 volts or less to be used

for experimental work, and permits temporary wiring of more than 600 volts to be used during

periods of tests and experiments. No specific time limit, in terms of days, weeks, or months, has

been established for temporary wiring used in experimental work. Rather, for this type of work,

temporary wiring is only permitted during the duration of an experiment.

In your scenario, it appears that the accelerator and other referenced research equipment are

permanently-installed, and the research laboratories have chosen not to temporarily install the

accelerators, other large equipment, and their supply wiring. Rather, the research laboratories

have selected a temporary wiring method and installed it permanently. The research equipment

wiring remains in place for years; thus, the wiring is permanent wiring. It should be noted,

however, that any wiring that is added to or removed from permanently-installed research

equipment to accommodate the running of specific experiments can be run as temporary wiring.

In contrast to the permanently-installed equipment, this wiring would be installed temporarily

and would need to be removed when the experiments calling for its use are concluded.2

Even though the supply wiring for accelerators and other permanently-installed equipment must

meet the requirements for permanent wiring methods, it may still be permissible to use flexible

cords or cables. Paragraph (g)(1) of §1910.305 lists nine specific situations in which flexible

cords may be used.3 (Even in these situations, flexible cords and cables must be approved and

286

suitable for the conditions of use and location.4) The following provides a partial listing of the

circumstances in which flexible cords and cables may be permitted for use at a research

laboratory. While §1910.305(g)(1)(i) lists several additional circumstances, those listed below

are the most likely to be applicable at a research laboratory:

1. pendants (typically, a lampholder or cord-connector body suspended by a length of cord

properly secured and terminated directly above the suspended device);

2. wiring of fixtures;

3. connection of portable lamps or appliances;

4. connection of stationary equipment to facilitate their frequent interchange; and

5. prevention of the transmission of noise or vibration (in some cases vibration may fatigue

fixed wiring and result in a situation more hazardous than flexible cord).

Unless flexible cords and cables are specifically permitted for use in situations detailed in

§1910.305(g)(1)(i), they must not be used. Furthermore, unless specifically permitted otherwise

by any of the nine permitted conditions, §1910.305(g)(1)(iii) requires that flexible cords and

cables may not be used:

1. as a substitute for the fixed wiring of a structure;

2. where run through holes in walls, ceiling, or floors;

3. where run through doorways, windows, or similar openings;

4. where attached to building surfaces; or

5. where concealed behind building walls, ceilings, or floors.

Question 2: What are the OSHA requirements for the type and quantity of cable (weight

loading) for cable trays, including the cable spacing requirements?

Reply: The Cable Trays requirements, contained in §1910.305(a)(3), address the general

installation and use requirements, including the types of cable permitted to be installed in cable

tray systems. In terms of the quantity (fill requirements) and weight (load requirements) of

cable(s) permitted in a tray and the spacing requirements between cables, these installation

specifications would be determined through the instruction included in the listing or labeling

associated with the particular cable tray system. As mentioned above, electrical equipment must

be approved and suitable for the conditions of use and location and used/installed in accordance

with general requirements for all conductors and equipment contained in §§1910.303(a) and

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(b).

This installation and use information should be included in the manufacturer's instructions.

Manufacturers typically incorporate recognized good engineering practice into their instructions,

such as including references to the National Electrical Code (NEC) and National Electrical

Manufacturers Association (NEMA) standards.5

In summary, the OSHA electrical standards require electrical equipment to be approved and

used/installed in accordance with any instructions included in the listing or labeling.

Manufacturers generally will provide this information on their product specifications to ensure

that their equipment and conductors are installed and used in accordance with the listing and

labeling requirements.

We hope you find this information helpful. If you have any further questions, please feel free to

contact the Office of General Industry Enforcement at (202) 693-1850.

1 The Department of Navy letter synonymizes the terms temporary wiring and flexible cords and

cables within the context of the response. As noted in the response below, these terms are not

synonymous, and there are separate and distinct requirements for temporary wiring and flexible

cords and cables, which are contained in §§1910.305(a)(2) and 1910.305(g), respectively.

[back to text]

2 This is further clarified in the Section 527.3(D) of the 2002 National Electrical Code, which

requires temporary wiring to be removed upon completion of the purpose for which the wiring

was installed. [back to text]

3 There is a definite need and place for flexible cords, but there also may be a temptation to

misuse them because they are perceived to offer a quick and easy way to carry electricity. The

basic problem with flexible cords is that they generally are more vulnerable than fixed wiring. In

many cases in which flexible cord is used, the protection associated with a recognized

permanent wiring method is diminished. Flexible cords may be used only when permitted by the

standard.

Furthermore, the provisions contained in the Electrical Safety-Related Work Practices standards

288

contain important safety requirements regarding the safe use of cord- and plug-connected

equipment, including flexible cord sets and extension cords. Specifically, some of the

requirements contained in the Use of equipment paragraph, 1910.334(a), address common safe

work practices for portable electric equipment. [back to text]

4 See §§1910.303(a) and (b) and §1910.305(g)(1) and also the definitions of approved,

acceptable, certified and listed contained in 1910.399. [back to text]

5 For your information, the Metal Cable Tray Systems (NEMA VE 1) standard contains maximum

allowable load specifications, and the Cable Tray Installation Guidelines (NEMA VE 2) require

cable trays to be installed in accordance with the NEC. For example, section 392.6(E) of the NEC

(2002) permits multiconductor cable rated at 600 volts or less (low-voltage) to be placed in the

same cable tray. The high-voltage multiconductor cable requirements are contained in section

392.6(F), and high-voltage multiconductor cable is required to be 1) type MC (metal-clad cable)

or 2) to be separated from low-voltage cable by a fixed barrier of a material compatible with the

cable tray. [back to text]

289

290

Small Business Handbook

www.osha.gov

Small Business Safety and

Health Management Series

OSHA 2209-02R 2005

291

Employers are responsible for providing a safe and

healthful workplace for their employees. OSHA’s

role is to assure the safety and health of America’s

workers by setting and enforcing standards; provid-

ing training, outreach and education; establishing

partnerships; and encouraging continual improve-

ment in workplace safety and health.

About this Handbook

This handbook is provided to owners, propri-etors and managers of small businesses by theOccupational Safety and Health Administration(OSHA), an agency of the U.S. Department ofLabor. For additional copies of this publication,write to the U.S. Government Printing Office,(GPO), Superintendent of Documents, Mail StopSDE, 732 N. Capitol Street, NW, Washington, DC20401, or call the OSHA Publications Office at (202)693-1888, or fax (202) 693-2498 for ordering infor-mation. Please note that the entire text of theSmall Business Handbook is available on OSHA’swebsite at http://www.osha.gov/Publications/osha2209.pdf.

The handbook should help small business em-ployers meet the legal requirements imposed bythe Occupational Safety and Health Act of 1970 (theAct), and achieve an in-compliance status before anOSHA inspection. An excellent resource to accom-pany this information is OSHA’s Safety and HealthProgram Management Guidelines, (54 FederalRegister 3904-3916, January 26, 1989), also avail-able on OSHA’s website.

This handbook is not a legal interpretation of theprovisions of the Act and does not place any addi-tional requirements on employers or employees.Employers cannot be cited under the General Duty

Clause in Section 5(a)(1) of the Act for failure to fol-low recommendations in this handbook.

The materials in this handbook are based uponFederal OSHA standards and other requirements ineffect at the time of publication and upon generallyaccepted principles and activities within the jobsafety and health field. They should be useful tosmall business owners or managers and can beadapted easily to individual establishments.

It is important to point out that 24 states, PuertoRico and the Virgin Islands operate their ownOSHA-approved safety and health programs underSection 18 of the Act. While the programs in theseState Plan States may differ in some respects fromFederal OSHA, this handbook can be used byemployers in any state because the standardsimposed by State Plan States must be at least aseffective as Federal OSHA standards. A list ofstates that operate their own safety and health pro-grams can be found on OSHA’s website atwww.osha.gov.

Material in this publication is in the publicdomain and may be reproduced, fully or partially,without permission. Source credit is requested butnot required.

This information will be made available to sen-sory impaired individuals upon request by voicephone (202) 693-1999 or teletypewriter (TTY) (877)889-5627.

Please Note: The small business employer seekinginformation on procurement or contracting with theDepartment of Labor or OSHA should contact theDepartment of Labor’s Office of Small BusinessPrograms, 200 Constitution Avenue, NW, Room C-2318, Washington, DC 20210.

292

Small Business HandbookOccupational Safety and Health AdministrationU.S. Department of Labor

OSHA 2209-02R2005

U.S. Department of Labor

www.osha.gov

293

PREFACE 4

Office of Small Business Assistance 4

Cooperative Programs 4

State Plans 4

Office of Training and Education 4

OSHA’s Website 5

Safety and Health Add Value 5

INTRODUCTION: The Value of a Safety and Health Management System 6

A Profit and Loss Statement 6

Developing a Profitable Strategy for Handling Occupational Safety and Health 6

A FOUR-POINT WORKPLACE PROGRAM: The Basis of a Plan 8

Using the Four-Point Program 8

MANAGEMENT COMMITMENT AND EMPLOYEE INVOLVEMENT 8

WORKSITE ANALYSIS 9

HAZARD PREVENTION AND CONTROL 9

TRAINING FOR EMPLOYEES, SUPERVISORS AND MANAGERS 10

Documenting Your Activities 11

Safety and Health Recordkeeping 11

INJURY/ILLNESS RECORDS 11

EXPOSURE RECORDS AND OTHERS 12

STARTING A SAFETY AND HEALTH MANAGEMENT SYSTEM: Creating a Plan 13

Decide to Start Now 13

Designating Responsibility 13

Ask for Help 13

Organize the Workplace 14

Start Gathering Specific Facts About Your Situation 14

Establish a Four-Point Safety and Health Program 15

Develop and Implement Your Action Plan 15

SELF-INSPECTION 17

Self-Inspection Scope 17

Self-Inspection Checklists 18

EMPLOYER POSTING 18

RECORDKEEPING 18

SAFETY AND HEALTH PROGRAM 18

MEDICAL SERVICES AND FIRST AID 19

FIRE PROTECTION 19

PERSONAL PROTECTIVE EQUIPMENT AND CLOTHING 20

GENERAL WORK ENVIRONMENT 20

WALKWAYS 21

FLOOR AND WALL OPENINGS 21

STAIRS AND STAIRWAYS 22

ELEVATED SURFACES 22

EXITING OR EGRESS - EVACUATION 22

EXIT DOORS 23

PORTABLE LADDERS 23

HAND TOOLS AND EQUIPMENT 24

PORTABLE (POWER OPERATED) TOOLS AND EQUIPMENT 24

ABRASIVE WHEEL EQUIPMENT GRINDERS 24

POWER-ACTUATED TOOLS 25

MACHINE GUARDING 25

LOCKOUT/TAGOUT PROCEDURES 26

WELDING, CUTTING AND BRAZING 27

COMPRESSORS AND COMPRESSED AIR 28

Contents

294

COMPRESSORS/AIR RECEIVERS 28

COMPRESSED GAS CYLINDERS 29

HOIST AND AUXILIARY EQUIPMENT 29

INDUSTRIAL TRUCKS - FORKLIFTS 29

SPRAYING OPERATIONS 30

ENTERING CONFINED SPACES 30

ENVIRONMENTAL CONTROLS 31

FLAMMABLE AND COMBUSTIBLE MATERIALS 32

HAZARDOUS CHEMICAL EXPOSURE 33

HAZARDOUS SUBSTANCES COMMUNICATION 34

ELECTRICAL 35

NOISE 37

FUELING 37

IDENTIFICATION OF PIPING SYSTEMS 37

MATERIALS HANDLING 38

TRANSPORTING EMPLOYEES AND MATERIALS 38

CONTROL OF HARMFUL SUBSTANCES BY VENTILATION 38

SANITIZING EQUIPMENT AND CLOTHING 39

TIRE INFLATION 39

ASSISTANCE IN SAFETY AND HEALTH FOR SMALL BUSINESSES 40

OSHA Assistance 40

OSHA’S OFFICE OF SMALL BUSINESS ASSISTANCE 40

ON-SITE CONSULTATION 40

OTHER COOPERATIVE PROGRAMS 41

VOLUNTARY PROTECTION PROGRAMS (VPP) 42

OSHA STRATEGIC PARTNERSHIP PROGRAM (OSPP) 42

OSHA ALLIANCE PROGRAM 42

States with Approved Plans 42

OSHA Publications 42

Other Sources of Assistance 43

VOLUNTARY PROTECTION PROGRAMS PARTICIPANTS’ ASSOCIATION (VPPPA) 43

SMALL BUSINESS DEVELOPMENT CENTERS 43

NATIONAL INSTITUTE FOR OCCUPATIONAL SAFETY AND HEALTH (NIOSH) 44

WORKERS’ COMPENSATION CARRIERS AND OTHER INSURANCE COMPANIES 44

TRADE ASSOCIATIONS AND EMPLOYER GROUPS 44

TRADE UNIONS AND EMPLOYEE GROUPS 44

THE NATIONAL SAFETY COUNCIL AND LOCAL CHAPTERS 44

PROFESSIONAL ASSOCIATIONS 44

SPECIFIC MEDICAL CONSULTATION 44

YOUR LOCAL LIBRARY 45

FINANCING WORKPLACE IMPROVEMENT 45

ADDITIONAL WEB PAGES OF INTEREST TO SMALL BUSINESSES 45

Appendix A: Overall Action Plan Worksheet 46

Appendix B: Model Policy Statements 48

Appendix C: Codes of Safe Practices 49

Appendix D: OSHA Job Safety and Health Standards, Regulations

and Requirements 50

Appendix E: Small Business Regulatory Enforcement Fairness Act of 1996 (SBREFA) 51

OSHA Regional Offices 52

OSHA’s Non-Retaliation Policy 53

295

OSHA HANDBOOK FOR SMALL BUSINESSES

PREFACE4

American employers and workers want safeand healthful places in which to work. They wanteveryone on the job to go home whole and healthyeach day. Determined to make that dream possi-ble, OSHA is committed to assuring – so far as pos-sible – that every working man and woman in thenation has safe and healthful working conditions.OSHA believes that providing workers with a safeworkplace is central to their ability to enjoy health,security and the opportunity to achieve theAmerican dream.

OSHA seeks to cut unnecessary rules, regula-tions and red tape. It is eliminating thousands ofpages of outdated regulations and continues torewrite standards in plain English. OSHA is paringdown its regulatory agenda so that it more accu-rately reflects realistic goals that best serve theneeds of American employers and employees.

Confronted by the realities and demands tokeep pace with the workforce and problems of thefuture, OSHA is developing new strategies toreduce occupational fatalities, injuries and illness-es. Coupled with strong, effective and fair enforce-ment, OSHA strives to provide improved outreach,education and compliance assistance to America’semployers and employees.

Office of Small Business Assistance

OSHA wants to provide quality service to oursmall business customers. In October 2002, OSHAcreated the Office of Small Business Assistance toprovide small business direction, to facilitate infor-mation sharing and to help in finding and achiev-ing regulatory compliance. The office also works toeducate small businesses on using up-to-date toolsand materials, and facilitates opportunities to com-ment on OSHA’s regulatory agenda. The Office ofSmall Business Assistance maintains OSHA’s spe-cialized small business web pages found at http://www.osha.gov/dcsp/smallbusiness/index.html.

The Office of Small Business Assistance can becontacted by telephone at (202) 693-2220 or bywriting to: Director, Office of Small BusinessAssistance, 200 Constitution Avenue, N.W., RoomN-3700, Washington, DC 20210.

Cooperative Programs

Years of experience show us that voluntary col-laborative relationships between OSHA, the private

sector and other government entities lead toimproved safety and health. As a result, OSHAcontinues to expand its cooperative programswhich currently include the free and confidentialConsultation Program, the Voluntary ProtectionPrograms, the Strategic Partnership Program andOSHA’s newest addition, Alliances. For a moredetailed description of each of these programs,please see pages 40- 42.

Small businesses are encouraged to investigatethe full array of cooperative programs offered byOSHA. Participation can be on an individual com-pany basis or through an industry association.Detailed information on each program is also avail-able on OSHA’s website at www.osha.gov, by con-tacting any OSHA office, or by calling (800) 321-OSHA.

State Plans

OSHA has important partnerships with the 24states, Puerto Rico and the Virgin Islands that oper-ate their own OSHA-approved safety and healthprograms. State workplace safety and health pro-grams frequently lead the way in developing inno-vative approaches to making America’s workplacessafer and healthier.

States that operate their own worker safety andhealth plans must provide worker protection that is“at least as effective as” the Federal program.However, because their standards and other proce-dures may vary, businesses should become famil-iar with their state regulations and agencies. SeeOSHA’s website for a list of State Plan States.

Office of Training and Education

OSHA’s Office of Training and Education provides training and instruction in all facets ofoccupational safety and health. OSHA’s TrainingInstitute, located in Arlington Heights, IL, providestraining for OSHA compliance safety and healthofficers as well as for the general public and safetyand health staff from other Federal agencies. Inaddition to OSHA’s Training Institute, there are 32additional education sites located throughout thecountry. These OSHA education centers operate inconjunction with universities, colleges and learningcenters to conduct OSHA courses for the privatesector and other Federal agencies, making safetyand health training and education more accessible

296

Occupational Safety and Health Administration

5

to those who need it. There are tuition fees for pri-vate sector students. For more information aboutOSHA’s Training Institute, OSHA’s education cen-ters, or to obtain training catalogs with courseschedules, write the OSHA Training Institute, 2020South Arlington Heights Road, Arlington Heights, IL60005 or call (847) 297-4810. The information isalso fully accessible on the Internet atwww.osha.gov.

OSHA’s Website

OSHA has made every effort to continuouslyexpand and improve its website. OSHA’s extensivewebsite provides employers and employees withpractical, easy-to-understand and up-to-date guid-ance on regulations, compliance assistance andlearning how to identify and control hazards. EachOSHA cooperative program has individual webpages describing program elements and highlight-ing successes of the participants. Several pagesare devoted to small business, technical links, newsitems, publication lists and an inventory of compli-ance assistance tools, including expert advisorsand e-tools. E-tools are “stand-alone” interactive,web-based training tools on occupational safetyand health topics. Regulations, standards, direc-tives and interpretations relating to OSHA can befound as well. There is a Spanish version of theOSHA website, and many posters and some publi-cations are also available in Spanish.

OSHA’s web pages include MyOSHA, whichallows users to create their own personalizedOSHA web page with customized content andlinks. Quick Start is another tool on OSHA’sCompliance Assistance web page that allows theuser to identify many of the major OSHA require-ments and guidance materials that apply to theirindividual workplaces or industry sectors.

Through its website, OSHA invites citizens to e-mail questions that can be routed to appropriateagency officials for response. Any communicationconducted via the “Contact Us” link on the OSHAwebsite is considered an informational exchangerather than an official communication with theDepartment of Labor. For an official response to aquestion or concern, inquiries should be submittedin writing.

If you would like to receive regular updatesfrom OSHA about new programs, tools, best prac-tices and other useful information, subscribe to theagency’s e-news memo, QuickTakes. QuickTakes isissued twice monthly to subscribers and is alwaysavailable online. You can subscribe to OSHA’sQuickTakes at www.osha.gov.

Safety and Health Add Value

Addressing safety and health issues in the work-place saves the employer money and adds value tothe business. Recent estimates place the businesscosts associated with occupational injuries at closeto $170 billion–expenditures that come straight outof company profits.

When workers stay whole and healthy, thedirect cost-savings to businesses include:

■ lower workers’ compensation insurance costs;■ reduced medical expenditures;■ smaller expenditures for return-to-work

programs;■ fewer faulty products;■ lower costs for job accommodations for

injured workers;■ less money spent for overtime benefits.

Safety and health also make big reductions inindirect costs, due to:

■ increased productivity;■ higher quality products;■ increased morale;■ better labor/management relations;■ reduced turnover;■ better use of human resources.

Employees and their families benefit from safety and health because:

■ their incomes are protected;■ their family lives are not hindered by injury;■ their stress is not increased.

Simply put, protecting people on the job is ineveryone’s best interest–our economy, our commu-nities, our fellow workers and our families. Safetyand health add value to businesses, workplacesand lives.

297

A Profit and Loss Statement

As a small business owner, you are, by nature, a risk taker. You wager your business acumenagainst larger, perhaps more heavily financed cor-porate groups and other free-spirited, self-employ-ed individuals like yourself. There is excitementand challenge in such a venture, but to succeedyou need good management information, an abili-ty to be a good manager of people and the intelli-gence and inner strength to make the right deci-sions.

Thousands of workers die each year and many,many more suffer injury or illness from conditionsat work. But how often does an owner or managerlike you actually see or even hear about work-relat-ed deaths, serious injuries or illnesses in the busi-nesses with which you are familiar? How often hasyour business actually sustained this type of loss?

In most small businesses, the answer is rarely.For this reason, many owners or managers do notunderstand why there is controversy about theOccupational Safety and Health Administration(OSHA), job safety and health standards, inspec-tions, citations, etc.

But others have learned why. Unfortunately,they have experienced a loss. These owner/man-agers will tell you that it is too late to do anythingonce a serious accident happens. They have learn-ed that prevention is the only real way to avoid thisloss.

Reducing losses is a goal that you as an owneror manager share with us in OSHA. While we maysee this goal in a slightly different light, it remainsa common bond.

We have learned from small employers, likeyou, that you place a high value on the well-beingof your employees. Like many small businesses,you may employ family members and personalacquaintances. And, if you don’t know your em-ployees before they are hired, then chances arethat the very size of your workplace will promotethe closeness and concern for one another thatsmall businesses value.

Assuming that you are committed to safe andhealthful work practices, OSHA wants to work withyou to prevent all losses. We believe that, when youmake job safety and health a real part of your every-day operations, you will not lose in the long run.Investing in safety and health activity now will betterenable you to avoid possible losses in the future.

Developing a Profitable Strategy forHandling Occupational Safety and Health

Nobody wants accidents to happen in his or herbusiness. A serious fire, a permanent injury, or thedeath of an employee or owner can cause the lossof profit or even an entire business. To preventsuch losses, you don’t have to turn your businessupside down. You may not have to spend a lot ofmoney, either. You do need to use good businesssense and apply recognized prevention principles.

There are reasons why accidents happen.Something goes wrong somewhere. It may takesome thought, and maybe the help of friends orother trained people, to figure out what wentwrong, but an accident always has a cause–a rea-son why. Once you know why an accident hap-pened, it is possible to prevent future incidents.You need some basic facts and perhaps some helpfrom others who already know some of the an-swers. You also need a plan–a plan to prevent acci-dents.

Not all dangers at your worksite depend on anaccident to cause harm, of course. Worker expo-sure to toxic chemicals or harmful levels of noiseor radiation may happen in conjunction with rou-

tine work as well as by accident. You may not real-ize the extent of the exposure or harm that you andyour employees face. The effect may not be imme-diate. You need a plan that includes prevention ofthese health hazard exposures and accidents. Youneed a safety and health management system.

It is not difficult to develop such a plan. Basi-cally, your plan should address the types of acci-dents and health hazard exposures that could hap-pen in your workplace. Because each workplace isdifferent, your program should address your spe-cific needs and requirements.

There are four basic elements to all good safetyand health programs. These are as follows:

1. Management Commitment and Employee

Involvement. The manager or management teamleads the way, by setting policy, assigning and sup-porting responsibility, setting an example and in-volving employees.

2.Worksite Analysis. The worksite is continually ana-lyzed to identify all existing and potential hazards.

3. Hazard Prevention and Control. Methods to pre-

INTRODUCTION: The Value of a Safety and Health Management System6


298

7


It will certainly give you a way to express and doc-ument your good faith and commitment to protect-ing your workers’ health and safety.

This approach usually does not involve largecosts. Developing a health and safety protectionplan does not have to be expensive and generallydoes not require additional employees, especiallyin smaller businesses. Safety and health can beintegrated into your other business functions withmodest effort on your part.

The key to the success of a safety and healthplan is to see it as a part of your business opera-tion and to see it reflected in your day-to-day oper-ations. As you implement the plan and incorporateit into your business culture, safety and healthawareness will become second nature to you andyour employees.

The next section provides short descriptionsand illustrations of each element. Since mostemployers, like you, are pressed for time, thesedescriptions will assist you in getting started onyour own approach.

vent or control existing or potential hazards are putin place and maintained.

4.Training for Employees, Supervisors and

Managers. Managers, supervisors and employeesare trained to understand and deal with worksitehazards.

Regardless of the size of your business, youshould use each of these elements to prevent work-place accidents and possible injuries and illnesses.

Developing a workplace program followingthese four points is a key step in protecting youand your workers’ safety and health. If you alreadyhave a program, reviewing it in relation to theseelements should help you improve what you have.

Following this four-point approach to safety andhealth in your business may also improve efficien-cy. It may help you reduce insurance claims andother costs. While having a safety and health planbased on these four elements does not guaranteecompliance with OSHA standards, the approachwill help you toward full compliance and beyond.

299

The Four-Point Workplace Program describedhere is based upon the Safety and Health ProgramManagement Guidelines issued by OSHA inJanuary 1989. (For a free copy of the guidelines,go to OSHA’s website at www.osha.gov, write toOSHA Publications, U.S. Department of Labor, P.O.Box 37535, Washington, DC 200013-7535, or call(202) 693-1888.) Although voluntary, these guide-lines represent OSHA’s policy on what every work-site should have in place to protect workers fromoccupational hazards. The guidelines are basedheavily on OSHA’s experience with its VoluntaryProtection Programs (VPP), which recognize excel-lence in workplace safety and health management.For more information on these guidelines andOSHA’s cooperative programs, contact OSHA’sOffice of Small Business Assistance, U.S.Department of Labor, 200 Constitution Avenue,NW, Room N-3700, Washington, DC 20210, (202)693-2220.

Using the Four-Point Program

As you review this publication, we encourageyou to use the Action Plan Worksheet in AppendixA to jot down the things you want to do to makeyour workplace safe for your employees. Notingthose actions as you go along will make it easier to assemble the total plan you need.

MANAGEMENT COMMITMENT AND

EMPLOYEE INVOLVEMENT

As the owner or manager of a small business,your attitude toward job safety and health will bereflected by your employees. If you are not inter-ested in preventing employee injury and illness,your employees will probably not give safety andhealth much thought either.

Therefore, it is essential that you demonstrate atall times your personal concern for employee safetyand health, and the priority you place on them inyour workplace. Your policy must be clear. Only youcan show its importance through your own actions.

You can demonstrate the depth of your commit-ment by involving your employees in planning andcarrying out your efforts. If you seriously involveyour employees in identifying and resolving safetyand health problems, they will bring their uniqueinsights and energy to achieving the goals andobjectives of your program. The men and womenwho work for you are among the most valuable

assets you have. Their safety, health and goodwillare essential to the success of your business. Hav-ing them cooperate with you in protecting theirsafety and health not only helps to keep themhealthy–it makes your job easier.

Here are some actions to consider:

■ Post your policy on worker safety and healthnext to the OSHA Workplace Poster where all employees can see it. (See Appendix B,Model Policy Statements.)

■ Hold a meeting with all employees to commu-nicate your safety and health policy, and dis-cuss your objectives for safety and health.

■ Make sure that your support is visible by get-ting personally involved in the activities thatare part of your safety and health program.For example, personally review all inspectionand accident reports and ensure that follow-up occurs when needed.

■ Ensure that you, your managers and yoursupervisors follow all safety requirements thatapply to all employees, even if you are only inan area briefly. If, for instance, you require ahard hat, safety glasses and/or safety shoes inan area, wear them yourself when you are inthat area.

■ Take advantage of your employees’ special-ized knowledge and encourage them to buyinto the program by having them make in-spections, conduct safety training, or investi-gate accidents.

■ Make clear assignments of responsibility forevery part of your safety and health program,and make sure everyone understands them.The more people who are involved, the better.A good rule of thumb is to assign safety andhealth responsibilities in the same way youassign production responsibilities. Make it aspecial part of everyone’s job to work safely.

■ Give those with safety and health responsibili-ty enough people, time, training, money andauthority to get the job done.

■ Don’t forget your safety and health program

8


A FOUR-POINT WORKPLACE PROGRAM: The Basis of a Plan

300

9


ards. The checklists (at pages 18-39) provide astarting point. Your state consultant can assistyou in establishing an effective system.

■ Make sure your employees feel comfortable inalerting you or another member of manage-ment when they see things that look danger-ous or out of place.

■ Learn how to conduct a thorough investiga-tion when things go wrong. This will help youdevelop ways to prevent recurrences. Exten-sive information can be found on OSHA’swebsite under “Accident Investigation” in theindex.

■ Review several years of injury or illness rec-ords to identify patterns that can help youdevise strategies to improve your safety andhealth program. Periodically review severalmonths of experience to determine if any newpatterns are developing.

HAZARD PREVENTION AND CONTROL

Once you have identified your existing andpotential hazards, you are ready to implement thesystems that prevent or control those hazards.Your state Consultation Program can help you dothis. Whenever possible, hazards should be elimi-nated. Sometimes that can be done through sub-stitution of a less toxic material or engineering con-trols. When you cannot eliminate hazards, systemsshould be established to control them.


■ Set up safe work procedures based on ananalysis of the hazards in your workplace andensure that employees understand and followthem. It is a good idea to involve employeesin the analysis that results in those procedures.(See Appendix C, Codes of Safe Practices.)

■ Be ready to enforce the rules for safe workprocedures. Ask your employees to help youestablish a disciplinary system that will be fairand understood by everyone.

■ Where necessary, ensure that personal protec-tive equipment (PPE) is used and that your em-ployees know why they need it, how to use itand how to maintain it.

after you make assignments; make sure thejob gets done. Recognize and reward thosewho do well and correct those who don’t.

■ At least once a year, review what you haveaccomplished in meeting your objectives andre-evaluate whether you need new objectivesor program revisions.

■ Institute an accountability system where allpersonnel will be held accountable for not fol-lowing work rules designed to promote work-place safety and health.

WORKSITE ANALYSIS

It is your responsibility to know what items orsubstances you have in your workplace that couldhurt your workers. Worksite analysis is a group ofprocesses that helps you make sure that you knowwhat you need to keep your workers safe. For helpin getting started with these processes, you can callon your state on-site Consultation Program andhave an experienced health and safety professionalvisit your workplace for free and confidentially.Locations for each state are listed on OSHA’s web-site. Also, OSHA’s booklet, Job Hazard Analysis,may be helpful. (See OSHA Publications at page42 for ordering information.)


■ Request a consultation visit from your stateon-site Consultation Program covering bothsafety and health to get a full survey of thehazards that exist in your workplace and thosethat could develop. You can also contract forsuch services from expert private consultantsif you prefer.

■ Establish a way to get professional advicewhen you make changes to procedures orequipment, to ensure that the changes are notintroducing new hazards into your workplace.Find ways to keep current on newly recog-nized hazards in your industry.

■ Periodically review with employees each job,analyzing it step-by-step to see if there are anyhidden hazards in the equipment or procedures.

■ Set up a self-inspection system to check yourhazard controls and evaluate any new haz-

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■ Provide for regular equipment maintenance toprevent breakdowns that can create hazards.Ensure that preventive and regular mainte-nance are tracked to completion.

■ Plan for emergencies, including fire and natu-ral disasters. Conduct frequent drills to en-sure that all employees know what to dounder stressful conditions.

■ Ask your state consultant to help develop amedical program that fits your worksite. In-volve nearby doctors and emergency facilitiesby inviting them to visit your workplace andhelp you plan the best way to avoid injuriesand illness during emergency situations.

■ Ensure the ready availability of medical per-sonnel for advice and consultation on mattersof employee health. This does not mean that

you must provide health care, but you mustbe prepared to deal with medical emergenciesor health problems connected to your work-place.

To fulfill the above requirements, consider thefollowing:

■ Develop an emergency medical procedure tohandle injuries, transport ill or injured workersand notify medical facilities. Posting emer-gency numbers is a good idea.

■ Survey the medical facilities near your placeof business and make arrangements for themto handle routine and emergency cases. Co-operative agreements may be possible withnearby larger workplaces that have on-sitemedical personnel and/or facilities.

■ Ensure that your procedure for reportinginjuries and illnesses is understood by allemployees.

■ Perform routine walkthroughs of the worksiteto identify hazards and to track identified haz-ards until they are corrected.

■ If your business is remote from medical facili-ties, you are required to ensure that adequate-ly trained personnel are available to render

first aid. First aid supplies must be readilyavailable for emergency use. Arrangementsfor this training can be made through yourlocal Red Cross chapter, your insurance carri-er, your local safety council, and others.

■ Check battery charging stations, maintenanceoperations, laboratories, heating and ventilat-ing operations and any corrosive materialsareas to make sure the required eye-washfacilities and showers are operational.

■ Consider retaining a local doctor or an occu-pational health nurse on a part-time or as-needed basis for advice on medical and firstaid planning.

TRAINING FOR EMPLOYEES, SUPERVISORS

AND MANAGERS

An effective accident prevention program re-quires proper job performance from everyone inthe workplace.

As an owner or manager, you must ensure thatall employees know about the materials and equip-ment they work with, known hazards and how tocontrol the hazards.

Each employee needs to know that:• no employee is expected to undertake a job until he or she has received job instructions on how to do it properly and is authorized to perform that job. Also,

• no employee should undertake a job that appears unsafe.

You may be able to combine safety and healthtraining with other training, depending upon thetypes of hazards in your workplace.


■ Ask your state consultant to recommend train-ing for your worksite. The consultant may beable to conduct training while he or she isthere.

■ Make sure you have trained your employeeson every potential hazard that they could beexposed to and how to protect themselves.Then verify that they really understand whatyou taught them.

■ Pay particular attention to your new employ-ees and to employees who are moving to new

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INJURY/ILLNESS RECORDS

OSHA rules for recording and reporting occupa-tional injuries and illnesses affect 1.4 million estab-lishments. Small businesses with 10 or feweremployees throughout the year are exempt frommost of the requirements of the OSHA recordkeep-ing rules, as are a number of specific industries in the retail, service, finance, insurance and realestate sectors that are classified as low-hazard.Detailed information about OSHA recordkeepingrules can be found at http://www.osha.gov/record-keeping/index.html or refer to 29 Code of FederalRegulations (CFR) 1904 for the specific exceptions.

OSHA recordkeeping can help the small busi-ness employer evaluate the success of safety andhealth activities. Success can be measured by areduction or elimination of employee injuries andillnesses during a calendar year.

The OSHA recordkeeping system has five steps:

1. Obtain a report on every injury or job-related ill-ness requiring medical treatment (other than basicfirst aid).

2. Record each injury or job-related illness onOSHA Form 300 (Log of Work-Related Injuries andIllnesses) using the instructions provided.

3. Prepare a supplementary record of occupationalinjuries and illnesses for recordable cases onOSHA Form 301 (Injury and Illness Incident Report).

4. Every year, prepare an annual summary usingOSHA Form 300A (Summary of Work-RelatedInjuries and Illnesses). Post it no later thanFebruary 1, and keep it posted until May 1. A goodplace to post it is next to the OSHA WorkplacePoster.

5. Retain these records for at least five years.

Periodically review these records to look for anypatterns or repeat situations. These records canhelp you to identify high-risk areas that requireyour immediate attention.

Basic OSHA recordkeeping requirementsaddress only injuries and illnesses, so you mightconsider expanding your own records to include all

jobs. Because they are learning new opera-tions, they are more likely to get hurt.

■ Train your supervisors to understand all thehazards faced by the employees and how toreinforce training with quick reminders andrefreshers, or with disciplinary action if neces-sary.

■ Make sure that your top management staffunderstand their safety and health responsi-bilities and how to hold subordinate supervi-sory employees accountable for theirs.

Documenting Your Activities

Document your activities in all elements of theFour-Point Workplace Program. Essential records,including those legally required for workers’ com-pensation, insurance audits and government in-spections must be maintained as long as the actualneed exists or as required by law. Keeping recordsof your activities, such as policy statements, train-ing sessions, safety and health meetings, informa-tion distributed to employees, and medicalarrangements made, is greatly encouraged.Maintaining essential records also will demonstratesound business management as supporting prooffor credit applications, for showing “good faith” inreducing any proposed penalties from OSHAinspections, for insurance and other audits, and aidefficient review of your current safety and healthactivities for better control of your operations andto plan improvements.

Safety and Health Recordkeeping

Records of sales, costs, profits and losses areessential to all successful businesses. They enablethe owner or manager to learn from experienceand to make corrections for future operations.Records of accidents, related injuries, illnesses andproperty losses can serve the same purpose, if theyare used in the same way. The primary purpose ofOSHA-required recordkeeping is to retain informa-tion about accidents that have happened to helpdetermine the causes and develop procedures toprevent a recurrence.

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incidents, including those where no injury or illnessresulted. This information may assist you in pin-pointing unsafe conditions and/or procedures.Safety councils, insurance carriers and others canassist you in instituting such a system.

The employer is required to report to OSHAwithin eight hours of the accident, all work-relatedfatalities or multiple hospitalizations that involvethree or more employees.

Even if your business is exempt from routinerecordkeeping requirements, you may be selectedby the Federal Bureau of Labor Statistics (BLS) or a related state agency for inclusion in an annualsample survey. You will receive a letter directly fromthe agency with instructions, if you are selected.

EXPOSURE RECORDS AND OTHERS

In addition to injury/illness records, certainOSHA standards require records on the exposureof employees to toxic substances and hazardousexposures, physical examination reports andemployment records.

As you identify hazards, you will be able todetermine whether these requirements apply toyour workplace. Your records should be used inconjunction with your control procedures and withyour self-inspection activity. They should not beconsidered merely as bookkeeping.

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Designating Responsibility

You must decide who in your company is themost appropriate person to manage your safetyand health system. Who can ensure that the pro-gram will become an integral part of your busi-ness? In many cases it will be you, the owner.Sometimes it will be a plant manager or key super-visor. It could even be an engineer, personnel spe-cialist, or other staff member.

Whoever you choose should be committed toworkplace safety and health, have the time to de-velop and manage the program, and be willing totake on the responsibility and accountability thatgoes with operating an effective program. The indi-vidual will need your full cooperation and support,but the ultimate responsibility for safety and healthin your workplace rests on you.

Ask for Help

Federal occupational safety and health lawallows a state to develop and operate its own occu-pational safety and health program in place of theFederal OSHA program. It is possible that the reg-ulatory aspect of the law (setting of mandatoryminimum standards and conducting inspections ofworkplaces) is being operated by your state gov-ernment as opposed to Federal OSHA.

One of the first things to learn is which branchof government, Federal or state, has current juris-diction over your business. If you are not surewhat agency is responsible for administering work-place safety and health in your state, contact thenearest OSHA Area Office to find out. (Seewww.osha.gov). You will need certain FederalOSHA publications (or comparable state publica-tions) for use in your safety and health activities,such as:

■ OSHA Workplace Poster (Job Safety andHealth Protection - OSHA 3165). You must dis-play the Federal or state OSHA poster in yourworkplace. This poster is also available inSpanish (Job Safety and Health ProtectionOSHA-3167).

■ OSHA standards that apply to your business.You need to have a copy of all OSHA stan-dards that apply to your type of businessavailable for reference. (See Appendix D.)

You can use this handbook to create a basicplan of action for starting a safety and healthmanagement system at your business. The actionplan described in this section provides the mostdirect route to getting yourself organized to com-plete the Four-Point Program outlined in the previ-ous section.

Decide to Start Now

The time to start your safety and health man-agement system is now. You have a better pictureof what constitutes a good safety and health pro-gram. Now you can address the practical concernsof putting these elements together and coming upwith a program to suit your workplace.

Hopefully, you have been taking notes for youraction plan as you reviewed the preceding de-scription of the Four-Point Program. You shouldnow be ready to decide what you want to accom-plish and to determine what steps are necessaryto achieve your goals. Next you need to deter-mine how and when each step will be done andwho will do it.

Your plan should consider your company’simmediate needs and provide for ongoing, long-lasting worker protection. Once your plan isdesigned, it is important to follow through anduse it in the workplace. You will then have a pro-gram to anticipate, identify and eliminate condi-tions or practices that could result in injuries andillnesses.

If you have difficulty deciding where to begin, aphone call to your state Consultation Program willhelp get you started. A state consultant will surveyyour workplace for existing or potential hazards.Then, if you request it, he or she will determinewhat you need to make your safety and health pro-gram effective. The consultant will work with youto develop a plan for making these improvementsand to keep your program effective.

Whether you choose to work with a consultantor to develop your program yourself, many publi-cations are available from your state on-site Con-sultation Program or from OSHA that spell out ingreater detail the steps you can take to create aneffective safety and health program for your work-place. The rewards for your efforts will be an effi-cient and productive workplace with a low level ofloss and injury.

STARTING A SAFETY AND HEALTH MANAGEMENT SYSTEM: Creating a Plan

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Standards are the regulations that OSHA usesto inspect for compliance and should be thebaseline for your inspections in determiningwhat to do when hazards are identified. Mostbusinesses fall under OSHA’s General IndustryStandards. If you are involved with construc-tion or maritime operations, you will need thestandards that apply to these classifications.(In states with state-run occupational safetyand health programs, use the appropriatestate standards.)

■ Recordkeeping requirements and the neces-sary forms.

■ Occupational Safety and Health Act of 1970.You may want a copy of this legislation forreference.

Organize the Workplace

Poor housekeeping can contribute to lowmorale and sloppy work. Most safety action pro-grams start with an intensive cleanup campaign inall areas of the workplace.

Get rid of unecessary items; provide properwaste containers; store flammables properly; makesure exits are not blocked; mark aisles and pas-sageways; provide adequate lighting, etc.

Get everyone involved and impress upon em-ployees that you want to make your workplacesafer, more healthful and more efficient.

Start Gathering Specific Facts About Your Situation

Before making changes in your safety andhealth operations, you should gather informationabout the current conditions and business practicesthat comprise your safety and health program.This information can help you identify problemsand determine what is needed to solve them.

Your workplace assessment should be conduct-ed by the person responsible for your safety andhealth management system and/or a professionalsafety and health consultant. The assessment con-sists of two major activities:

1. A comprehensive safety and health survey ofyour entire facility will identify any existing orpotential safety and health hazards. This initial sur-

vey should focus on evaluating workplace condi-tions with respect to safety and health regulationsand generally recognized safe and healthful workpractices. It should include checking on the use ofany hazardous materials, observing employee workhabits and practices, and discussing safety andhealth problems with employees. See the Self-Inspection Checklists (at pages 18-39), to help youget a good start on creating this initial survey.

2. The second major activity is to assess your exist-ing safety and health program and identify areasthat work well and those that need improvement.You should gather as much information as you canthat relates to safety and health management inyour workplace. You should include the followingin this review:

■ Safety and health activities. Examine ongo-ing activities as well as those tried previously,company policy statements, rules (both workand safety), guidelines for proper work prac-tices and procedures, and records of trainingprograms.

■ Equipment. List your major equipment, whatit is used for and where it is located. Specialattention should be given to inspection sched-ules, maintenance activities, and plant andoffice layouts.

■ Employee capabilities. Make an alphabeticallist of all employees, showing the date hired,their job descriptions, and experience andtraining.

■ Accident and injury/illness history. Reviewfirst aid cases and workers’ compensationinsurance payments and awards, and reviewyour losses. Compare your insurance ratewith others in your group. Give special atten-tion to recurring accidents, types of injuries,etc.

After gathering facts, see if any major problemareas emerge such as interruptions in your normaloperations, too many employees taking too muchtime off due to illness or injury, too many damagedproducts, etc. General help with this kind of prob-lem identification can often be obtained from com-pensation carriers, local safety councils, trade asso-

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Establish and regularly conduct a worksite

analysis. A successful safety and health programdepends on an accurate identification of all the haz-ards and potential hazards in your workplace. Thisis an ongoing process that includes routine self-inspections.

Create systems and procedures to prevent and

control hazards identified through your worksiteanalysis. OSHA standards can be helpful becausethey address controls in order of effectiveness andpreference. The hierarchy of controls is engineer-ing, administrative, work practice and PPE. When-ever feasible, engineering, administrative or workpractice controls should be instituted even if theydo not eliminate the hazard or reduce exposure.Use of such controls in conjunction with PPE willhelp reduce the hazard or exposure to the lowestpractical level. Where no standard exists, creativeproblem-solving and consultant resources mayhelp you create effective controls. The basic formu-la for controlling workplace hazards, in order ofpreference, includes:

■ Eliminating the hazard from the machine, themethod, the material or the facility.

■ Abating the hazard by limiting exposure orcontrolling it at its source.

■ Training personnel to be aware of the hazardand to follow safe work procedures to avoid it.

■ Prescribing PPE for protecting employeesagainst the hazard and ensuring that they notonly use it, but that they know how to use itcorrectly.

Establish and provide ongoing training for

employees, supervisors and managers to ensurethat everyone at your worksite can recognize haz-ards and how to control them.

These points are crucial to a safe and healthfulworkplace for you and your employees, making itmore difficult for accidents to occur and for work-related health problems to develop.

Develop and Implement Your Action Plan

Developing an action plan to build a safety andhealth program around the four points can serve asa “road map” to take your program to where you

ciations, state agencies, major suppliers or similar-ly situated businesses in the same industry.

If you discover a major problem, see what canbe done to solve it. Once a problem is identified,you can work on the corrective action or a plan tocontrol the problem. Take immediate action andmake a record of what you have done. Even if youfind no major problems, don’t stop there. Now it istime to develop a comprehensive safety and healthprogram to avoid any major problems in the future.

Establish a Four-Point Safety and Health Program

The success of any workplace safety and healthprogram depends on careful planning. This meansthat you must take the time to analyze what youwant to accomplish and develop an action plan inorder to attain your goals. From this standpoint,you can design a step-by-step process to take youfrom the idea stage to an effective safety andhealth management system.

The best way to create a safe and healthfulworkplace is to institute the Four-Point Programdiscussed at page 8 of this handbook.

Establish your management commitment andinvolve your employees. No safety and health program will work without this commitment andinvolvement. The first step is to designate a person tobe responsible for your safety and health program.

Involve your employees as widely as possiblefrom the beginning. They are most in contact withthe potential and actual safety and health hazardsat your worksite and will have constructive inputon the development of your program. The ultimatesuccess of your safety and health program willdepend on their support.

Make sure your program assigns responsibilityand accountability to all employees in your organi-zation. A good safety and health program makes itclear that each and every employee, from youthrough the supervisory levels to the line worker,carries responsibility for his or her part of the pro-gram. Make safety and health duties clear andhold every individual accountable for his or hersafety- and health-related duties.

Refer to the recommended actions to take in theWorksite Analysis paragraph at page 9. These willhelp start your program off on the right track. Youwill be building the foundation for a successfulsafety and health program.

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want it to be. An action plan tells you what has tobe done, the logical order in which to do it, who isresponsible and where you want to be when youfinish. It describes problems and solutions, but isnot ironclad. An action plan can and should bechanged to correspond with changes in the work-place.

A good action plan has two parts:

1. A list of major changes or improvements to makeyour safety and health program effective. Eachitem should be prioritized, have a target date forcompletion and identify who is responsible forimplementation.

2. A specific plan to implement each major changeor improvement, including what you want toaccomplish, the steps required, who will beassigned to do what and a schedule for comple-tion.

A worksheet to help you design an overallaction plan and describe specific action stepsappears in Appendix A.

Once a plan is established, put it into action,beginning with the highest priority item. Ensurethat it is realistic, manageable and addresses thesteps you have planned for that item. A detaileddescription of the steps required will help you keeptrack of your progress. Keep in mind that you canwork on more than one item at a time and that pri-orities may change as other needs are identified oras your company’s resources change.

Open communication with your employees iscrucial to the success of your efforts. Their cooper-ation depends on them understanding what thesafety and health program is all about, why it isimportant to them and how it affects their work.The more you do to involve them in the changes youare making, the smoother your transition will be.

Putting your action plan into operation at yourworkplace will be a major step toward implement-ing an effective safety and health program.

Remember, a safety and health program is a plan

put into practice. Keep your program on track byperiodically checking its progress and by calling ona state consultant when you need assistance.

Any good management system requires period-ic review. Take a careful look at each component ofyour safety and health program to determine whatis working well and what changes are needed.Once again, a state consultant can assist you in thisarea. Any necessary improvements can be turnedinto new safety and health objectives for the com-ing year. Developing new action plans to imple-ment these improvements will continue progresstoward an effective safety and health program,reduce your safety and health risks, and increaseefficiency and profit.

Remember that it is important to documentyour activities. The best way to evaluate the suc-cess of your safety and health program is to havedocumentation of what you have done, which pro-vides guidance on how you can make it work evenbetter.

Technical assistance may be available to you asa small business owner or manager through yourinsurance carrier; your fellow business-people; sup-pliers of your durable equipment and raw materi-als; the local safety council; and many local, stateand Federal agencies, including the state on-siteConsultation Programs and closest OSHA AreaOffice.

Establishing a quality safety and health man-agement system will take time and involve someresources, but you should be pleased with theresults. Employees will feel reassured because ofyour commitment to their safety and health on thejob. You may save money through increased pro-ductivity and reduced workers’ compensation in-surance costs. You may gain increased respect inyour community. The tangible and intangible re-wards for a solid safety and health program faroutweigh the cost of an accident, injury or work-place fatality.

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■ Building and Grounds Conditions – floors,walls, ceilings, exits, stairs, walkways, ramps,platforms, driveways, aisles.

■ Housekeeping Program – waste disposal,tools, objects, materials, leakage and spillage,cleaning methods, schedules, work areas,remote areas, storage areas.

■ Electricity – equipment, switches, breakers,fuses, switch-boxes, junctions, special fixtures,circuits, insulation, extensions, tools, motors,grounding, national electric code compliance.

■ Lighting – type, intensity, controls, conditions,diffusion, location, glare and shadow control.

■ Heating and Ventilation – type, effectiveness,temperature, humidity, controls, natural andartificial ventilation and exhausting.

■ Machinery – points of operation, flywheels,gears, shafts, pulleys, key ways, belts, cou-plings, sprockets, chains, frames, controls,lighting for tools and equipment, brakes, ex-hausting, feeding, oiling, adjusting, mainte-nance, lockout/tagout, grounding, work space,location, purchasing standards.

■ Personnel – training, including hazard identifi-cation training; experience; methods of check-ing machines before use; type of clothing;PPE; use of guards; tool storage; work prac-tices; methods for cleaning, oiling, or adjust-ing machinery.

■ Hand and Power Tools – purchasing stan-dards, inspection, storage, repair, types, main-tenance, grounding, use and handling.

■ Chemicals – storage, handling, transportation,spills, disposals, amounts used, labeling, toxi-city or other harmful effects, warning signs,supervision, training, protective clothing andequipment, hazard communication require-ments.

■ Fire Prevention – extinguishers, alarms, sprin-klers, smoking rules, exits, personnel assign-ed, separation of flammable materials anddangerous operations, explosion-proof fix-

The most widely accepted way to identify haz-ards is to conduct safety and health inspectionsbecause the only way to be certain of an actual sit-uation is to look at it directly from time to time.

Begin a program of self-inspection in your ownworkplace. Self-inspection is essential if you are toknow where probable hazards exist and whetherthey are under control.

This section includes checklists designed toassist you in self-inspection fact-finding. The check-lists can give you some indication of where tobegin taking action to make your business saferand more healthful for all of your employees.

These checklists are by no means all-inclusive

and not all of the checklists will apply to your busi-ness. You might want to start by selecting theareas that are most critical to your business, thenexpanding your self-inspection checklists over timeto fully cover all areas that pertain to your busi-ness. Remember that a checklist is a tool to help,not a definitive statement of what is mandatory.Use checklists only for guidance.

Don’t spend time with items that have no appli-

cation to your business. Make sure that each itemis seen by you or your designee and leave nothingto memory or chance. Write down what you see ordon’t see and what you think you should do about it.

Add information from your completed checkliststo injury information, employee information, andprocess and equipment information to build afoundation to help you determine what problemsexist. Then, as you use the OSHA standards inyour problem-solving process, it will be easier foryou to determine the actions needed to solve theseproblems.

Once the hazards have been identified, insti-tute the control procedures described at page 9and establish your four-point safety and healthprogram.

Self-Inspection Scope

Your self-inspections should cover safety andhealth issues in the following areas:

■ Processing, Receiving, Shipping and Storage –equipment, job planning, layout, heights, floorloads, projection of materials, material han-dling and storage methods, training for mate-rial handling equipment.

SELF-INSPECTION

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tures in hazardous locations, waste disposaland training of personnel.

■ Maintenance – provide regular and preventivemaintenance on all equipment used at theworksite, recording all work performed on themachinery and by training personnel on theproper care and servicing of the equipment.

■ PPE – type, size, maintenance, repair, age, stor-age, assignment of responsibility, purchasingmethods, standards observed, training in careand use, rules of use, method of assignment.

■ Transportation – motor vehicle safety, seat belts,vehicle maintenance, safe driver programs.

■ First Aid Program/Supplies – medical carefacilities locations, posted emergency phonenumbers, accessible first aid kits.

■ Evacuation Plan – establish and practice pro-cedures for an emergency evacuation, e.g.,fire, chemical/biological incidents, bombthreat; include escape procedures and routes,critical plant operations, employee accountingfollowing an evacuation, rescue and medicalduties and ways to report emergencies.

Self-Inspection Checklists

These checklists are by no means all-inclusive.You should add to them or delete items that do notapply to your business; however, carefully considereach item and then make your decision. You shouldrefer to OSHA standards for specific guidance thatmay apply to your work situation. (Note: Thesechecklists are typical for general industry but not forconstruction or maritime industries.)

EMPLOYER POSTING

❏ Is the required OSHA Job Safety and HealthProtection Poster displayed in a prominent loca-tion where all employees are likely to see it?

❏ Are emergency telephone numbers postedwhere they can be readily found in case ofemergency?

❏ Where employees may be exposed to toxicsubstances or harmful physical agents, has

appropriate information concerning employeeaccess to medical and exposure records andMaterial Safety Data Sheets (MSDSs) beenposted or otherwise made readily available toaffected employees?

❏ Are signs concerning exit routes, room capaci-ties, floor loading, biohazards, exposures to x-ray, microwave, or other harmful radiation orsubstances posted where appropriate?

❏ Is the Summary of Work-Related Injuries andIllnesses (OSHA Form 300A) posted during themonths of February, March and April?

RECORDKEEPING

❏ Are occupational injuries or illnesses, exceptminor injuries requiring only first aid, recordedas required on the OSHA 300 log?

❏ Are employee medical records and records ofemployee exposure to hazardous substancesor harmful physical agents up-to-date and incompliance with current OSHA standards?

❏ Are employee training records kept and acces-sible for review by employees, as required byOSHA standards?

❏ Have arrangements been made to retainrecords for the time period required for eachspecific type of record? (Some records mustbe maintained for at least 40 years.)

❏ Are operating permits and records up-to-datefor items such as elevators, air pressure tanks,liquefied petroleum gas tanks, etc.?

SAFETY AND HEALTH PROGRAM

❏ Do you have an active safety and health pro-gram in operation that includes general safetyand health program elements as well as themanagement of hazards specific to your work-site?

❏ Is one person clearly responsible for the safetyand health program?

❏ Do you have a safety committee or groupmade up of management and labor represen-tatives that meets regularly and reports inwriting on its activities?

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❏ If employees have had an exposure incidentinvolving bloodborne pathogens, was an im-mediate post-exposure medical evaluation andfollow-up provided?

❏ Are medical personnel readily available foradvice and consultation on matters of employ-ees’ health?

❏ Are emergency phone numbers posted?

❏ Are fully supplied first aid kits easily accessibleto each work area, periodically inspected andreplenished as needed?

❏ Have first aid kits and supplies been approvedby a physician, indicating that they are ade-quate for a particular area or operation?

❏ Is there an eye-wash station or sink availablefor quick drenching or flushing of the eyes andbody in areas where corrosive liquids or mate-rials are handled?

FIRE PROTECTION

❏ Is your local fire department familiar with yourfacility, its location and specific hazards?

❏ If you have a fire alarm system, is it certifiedas required and tested annually?

❏ If you have interior standpipes and valves, arethey inspected regularly?

❏ If you have outside private fire hydrants, arethey flushed at least once a year and on a rou-tine preventive maintenance schedule?

❏ Are fire doors and shutters in good operatingcondition?

❏ Are fire doors and shutters unobstructed andprotected against obstructions, including theircounterweights?

❏ Are fire door and shutter fusible links in place?

❏ Are automatic sprinkler system water controlvalves, air and water pressure checked periodi-cally as required?

❏ Is the maintenance of automatic sprinkler sys-tems assigned to responsible persons or to asprinkler contractor?

❏ Are sprinkler heads protected by metal guardsif exposed to potential physical damage?

❏ Do you have a working procedure to handlein-house employee complaints regarding safe-ty and health?

❏ Are your employees advised of efforts andaccomplishments of the safety and health pro-gram made to ensure they will have a work-place that is safe and healthful?

❏ Have you considered incentives for employeesor workgroups who excel in reducing work-place injury/illnesses?

MEDICAL SERVICES AND FIRST AID

❏ Is there a hospital, clinic, or infirmary for med-ical care near your workplace or is at least oneemployee on each shift currently qualified torender first aid?

❏ Have all employees who are expected torespond to medical emergencies as part oftheir job responsibilities received first aidtraining; had hepatitis B vaccination madeavailable to them; had appropriate training onprocedures to protect them from bloodbornepathogens, including universal precautions;and have available and understand how to useappropriate PPE to protect against exposure tobloodborne diseases?*

*Pursuant to an OSHA memorandum of July 1,1992, employees who render first aid only as a col-lateral duty do not have to be offered pre-exposurehepatitis B vaccine only if the employer includesand implements the following requirements inhis/her exposure control plan: (1) the employermust record all first aid incidents involving thepresence of blood or other potentially infectiousmaterials before the end of the work shift duringwhich the first aid incident occurred; (2) the em-ployer must comply with post-exposure evaluation,prophylaxis and follow-up requirements of theBloodborne Pathogens standard with respect to“exposure incidents,” as defined by the standard;(3) the employer must train designated first aidproviders about the reporting procedure; (4) theemployer must offer to initiate the hepatitis B vac-cination series within 24 hours to all unvaccinatedfirst aid providers who have rendered assistance inany situation involving the presence of blood orother potentially infectious materials.

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❏ Is proper clearance maintained below sprinklerheads?

❏ Are portable fire extinguishers provided inadequate number and type and mounted inreadily accessible locations?

❏ Are fire extinguishers recharged regularly withthis noted on the inspection tag?

❏ Are employees periodically instructed in theuse of fire extinguishers and fire protectionprocedures?

PERSONAL PROTECTIVE EQUIPMENT

AND CLOTHING

❏ Has the employer determined whether hazardsthat require the use of PPE (e.g., head, eye,face, hand, or foot protection) are present orare likely to be present?

❏ If hazards or the likelihood of hazards arefound, are employers selecting appropriateand properly fitted PPE suitable for protectionfrom these hazards and ensuring that affectedemployees use it?

❏ Have both the employer and the employeesbeen trained on PPE procedures, i.e., what PPEis necessary for job tasks, when workers needit, and how to properly wear and adjust it?

❏ Are protective goggles or face shields provid-ed and worn where there is any danger of fly-ing particles or corrosive materials?

❏ Are approved safety glasses required to beworn at all times in areas where there is a riskof eye injuries such as punctures, abrasions,contusions, or burns?

❏ Are employees who wear corrective lenses(glasses or contacts) in workplaces with harm-ful exposures required to wear only approvedsafety glasses, protective goggles, or useother medically approved precautionary proce-dures?

❏ Are protective gloves, aprons, shields, or othermeans provided and required where employ-ees could be cut or where there is reasonablyanticipated exposure to corrosive liquids,chemicals, blood, or other potentially infec-tious materials? See the OSHA Bloodborne

Pathogens standard, 29 CFR 1910.1030(b), forthe definition of “other potentially infectiousmaterials.”

❏ Are hard hats required, provided and wornwhere danger of falling objects exists?

❏ Are hard hats periodically inspected for dam-age to the shell and suspension system?

❏ Is appropriate foot protection required wherethere is the risk of foot injuries from hot, corro-sive, or poisonous substances, falling objects,crushing, or penetrating actions?

❏ Are approved respirators provided when need-ed? (See 29 CFR 1910.134 for detailed infor-mation on respirators or check OSHA’s websiteat www.osha.gov).

❏ Is all PPE maintained in a sanitary conditionand ready for use?

❏ Are food or beverages consumed only in areaswhere there is no exposure to toxic material,blood, or other potentially infectious materials?

❏ Is protection against the effects of occupation-al noise provided when sound levels exceedthose of the OSHA Noise standard?

❏ Are adequate work procedures, PPE and otherequipment provided and used when cleaningup spilled hazardous materials?

❏ Are appropriate procedures in place to disposeof or decontaminate PPE contaminated with,or reasonably anticipated to be contaminatedwith, blood or other potentially infectiousmaterials?

GENERAL WORK ENVIRONMENT

❏ Are all worksites clean, sanitary and orderly?

❏ Are work surfaces kept dry and appropriatemeans taken to assure the surfaces are slip-resistant?

❏ Are all spilled hazardous materials or liquids,including blood and other potentially infec-tious materials, cleaned up immediately andaccording to proper procedures?

❏ Is combustible scrap, debris and wastestored safely and removed from the worksitepromptly?

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❏ Are spilled materials cleaned up immediately?

❏ Are changes of direction or elevations readilyidentifiable?

❏ Are aisles or walkways that pass near movingor operating machinery, welding operations,or similar operations arranged so employeeswill not be subjected to potential hazards?

❏ Is adequate headroom provided for the entirelength of any aisle or walkway?

❏ Are standard guardrails provided whereveraisle or walkway surfaces are elevated morethan 30 inches (76.20 centimeters) above anyadjacent floor or the ground?

❏ Are bridges provided over conveyors and sim-ilar hazards?

FLOOR AND WALL OPENINGS

❏ Are floor openings guarded by a cover, aguardrail, or equivalent on all sides (except atstairways or ladder entrances)?

❏ Are toeboards installed around the edges ofpermanent floor openings where persons maypass below the opening?

❏ Are skylight screens able to withstand a loadof at least 200 pounds (90.7 kilograms)?

❏ Is the glass in windows, doors, glass walls,etc., subject to possible human impact, of suf-ficient thickness and type for the condition ofuse?

❏ Are grates or similar type covers over flooropenings such as floor drains designed toallow unimpeded foot traffic or rolling equip-ment?

❏ Are unused portions of service pits and pitsnot in use either covered or protected byguardrails or equivalent?

❏ Are manhole covers, trench covers and similarcovers, and their supports designed to carry atruck rear axle load of at least 20,000 pounds(9,072 kilograms) when located in roadwaysand subject to vehicle traffic?

❏ Are floor or wall openings in fire-resistant con-struction provided with doors or covers com-patible with the fire rating of the structure and

❏ Is all regulated waste, as defined in the OSHABloodborne Pathogens standard (29 CFR1910.1030), discarded according to Federal,state and local regulations?

❏ Are accumulations of combustible dust rou-tinely removed from elevated surfaces includ-ing the overhead structure of buildings, etc.?

❏ Is combustible dust cleaned up with a vacuumsystem to prevent suspension of dust particlesin the environment?

❏ Is metallic or conductive dust prevented fromentering or accumulating on or around electri-cal enclosures or equipment?

❏ Are covered metal waste cans used for oily orpaint-soaked waste?

❏ Are all oil and gas-fired devices equipped withflame failure controls to prevent flow of fuel ifpilots or main burners are not working?

❏ Are paint spray booths, dip tanks, etc., cleanedregularly?

❏ Are the minimum number of toilets and wash-ing facilities provided and maintained in aclean and sanitary fashion?

❏ Are all work areas adequately illuminated?

❏ Are pits and floor openings covered or other-wise guarded?

❏ Have all confined spaces been evaluated forcompliance with 29 CFR 1910.146? (Permit-required confined spaces.)

WALKWAYS

❏ Are aisles and passageways kept clear andmarked as appropriate?

❏ Are wet surfaces covered with non-slip mate-rials?

❏ Are holes in the floor, sidewalk, or other walk-ing surface repaired properly, covered, or oth-erwise made safe?

❏ Is there safe clearance for walking in aisleswhere motorized or mechanical handlingequipment is operating?

❏ Are materials or equipment stored in such away that sharp projections will not interferewith the walkway?

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provided with a self-closing feature whenappropriate?

STAIRS AND STAIRWAYS

❏ Do standard stair rails or handrails on all stair-ways have at least four risers?

❏ Are all stairways at least 22 inches (55.88 cen-timeters) wide?

❏ Do stairs have landing platforms not less than30 inches (76.20 centimeters) in the directionof travel and extend 22 inches (55.88 centime-ters) in width at every 12 feet (3.6576 meters)or less of vertical rise?

❏ Do stairs angle no more than 50 and no lessthan 30 degrees?

❏ Are stairs of hollow-pan type treads and land-ings filled to the top edge of the pan with solidmaterial?

❏ Are step risers on stairs uniform from top tobottom?

❏ Are steps slip-resistant?

❏ Are stairway handrails located between 30inches (76.20 centimeters) and 34 inches (86.36centimeters) above the leading edge of stairtreads?

❏ Do stairway handrails have at least 3 inches(7.62 centimeters) of clearance between thehandrails and the wall or surface they aremounted on?

❏ Where doors or gates open directly on a stair-way, is a platform provided so the swing ofthe door does not reduce the width of the plat-form to less than 21 inches (53.34 centime-ters)?

❏ Are stairway handrails capable of withstandinga load of 200 pounds (90.7 kilograms), appliedwithin 2 inches (5.08 centimeters) of the topedge in any downward or outward direction?

❏ Where stairs or stairways exit directly into anyarea where vehicles may be operated, are ade-quate barriers and warnings provided to pre-vent employees from stepping into the path oftraffic?

❏ Do stairway landings have a dimension meas-ured in the direction of travel at least equal tothe width of the stairway?

❏ Is the vertical distance between stairway land-ings limited to 12 feet (3.6576 meters) or less?

ELEVATED SURFACES

❏ Are signs posted, when appropriate, showingthe elevated surface load capacity?

❏ Are surfaces that are elevated more than 30inches (76.20 centimeters) provided with stan-dard guardrails?

❏ Are all elevated surfaces beneath which peo-ple or machinery could be exposed to fallingobjects provided with standard 4-inch (10.16-centimeter) toeboards?

❏ Is a permanent means of access and egressprovided to elevated storage and work sur-faces?

❏ Is required headroom provided where neces-sary?

❏ Is material on elevated surfaces piled, stacked,or racked in a manner to prevent it from tip-ping, falling, collapsing, rolling, or spreading?

❏ Are dock boards or bridge plates used whentransferring materials between docks andtrucks or railcars?

EXITING OR EGRESS - EVACUATION

❏ Are all exits marked with an exit sign and illu-minated by a reliable light source?

❏ Are the directions to exits, when not immedi-ately apparent, marked with visible signs?

❏ Are doors, passageways or stairways that areneither exits nor access to exits, but could bemistaken for exits, appropriately marked “NOTAN EXIT,” “TO BASEMENT,” “STOREROOM,”etc.?

❏ Are exit signs labeled with the word “EXIT” inlettering at least 5 inches (12.70 centimeters)high and the stroke of the lettering at least l/2-inch (1.2700 centimeters) wide?

❏ Are exit doors side-hinged?

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❏ Where panic hardware is installed on arequired exit door, will it allow the door toopen by applying a force of 15 pounds (6.80kilograms) or less in the direction of the exittraffic?

❏ Are doors on cold storage rooms providedwith an inside release mechanism that willrelease the latch and open the door even if thedoor is padlocked or otherwise locked on theoutside?

❏ Where exit doors open directly onto anystreet, alley, or other area where vehicles maybe operated, are adequate barriers and warn-ings provided to prevent employees fromstepping into the path of traffic?

❏ Are doors that swing in both directions andare located between rooms where there is fre-quent traffic provided with viewing panels ineach door?

PORTABLE LADDERS

❏ Are all ladders maintained in good condition,joints between steps and side rails tight, allhardware and fittings securely attached, andmoveable parts operating freely without bind-ing or undue play?

❏ Are non-slip safety feet provided on each metalor rung ladder, and are ladder rungs and stepsfree of grease and oil?

❏ Are employees prohibited from placing a lad-der in front of doors opening toward the lad-der unless the door is blocked open, locked, orguarded?

❏ Are employees prohibited from placing lad-ders on boxes, barrels, or other unstable basesto obtain additional height?

❏ Are employees required to face the ladderwhen ascending or descending?

❏ Are employees prohibited from using laddersthat are broken, have missing steps, rungs, orcleats, broken side rails, or other faulty equip-ment?

❏ Are employees instructed not to use the topstep of ordinary stepladders as a step?

❏ Are all exits kept free of obstructions?

❏ Are at least two means of egress providedfrom elevated platforms, pits, or rooms wherethe absence of a second exit would increasethe risk of injury from hot, poisonous, corro-sive, suffocating, flammable, or explosive sub-stances?

❏ Are there sufficient exits to permit promptescape in case of emergency?

❏ Are special precautions taken to protectemployees during construction and repairoperations?

❏ Is the number of exits from each floor of abuilding and the number of exits from thebuilding itself appropriate for the buildingoccupancy load?

❏ Are exit stairways that are required to be sepa-rated from other parts of a building enclosedby at least 2-hour fire-resistive construction inbuildings more than four stories in height, andnot less than 1-hour fire-resistive constructionelsewhere?

❏ Where ramps are used as part of required exit-ing from a building, is the ramp slope limitedto 1 foot (0.3048 meter) vertical and 12 feet(3.6576 meters) horizontal?

❏ Where exiting will be through frameless glassdoors, glass exit doors, storm doors, etc., arethe doors fully tempered and meet the safetyrequirements for human impact?

EXIT DOORS

❏ Are doors that are required to serve as exitsdesigned and constructed so that the path ofexit travel is obvious and direct?

❏ Are windows that could be mistaken for exitdoors made inaccessible by means of barriersor railings?

❏ Are exit doors able to be opened from thedirection of exit travel without the use of a keyor any special knowledge or effort when thebuilding is occupied?

❏ Is a revolving, sliding, or overhead door pro-hibited from serving as a required exit door?

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❏ When portable rung ladders are used to gainaccess to elevated platforms, roofs, etc., doesthe ladder always extend at least 3 feet (0.9144meters) above the elevated surface?

❏ Are employees required to secure the base ofa portable rung or cleat type ladder to preventslipping, or otherwise lash or hold it in place?

❏ Are portable metal ladders legibly markedwith signs reading “CAUTION - Do Not UseAround Electrical Equipment” or equivalentwording?

❏ Are employees prohibited from using laddersas guys, braces, skids, gin poles, or for otherthan their intended purposes?

❏ Are employees instructed to only adjust exten-sion ladders while standing at a base (notwhile standing on the ladder or from a posi-tion above the ladder)?

❏ Are metal ladders inspected for damage?

❏ Are the rungs of ladders uniformly spaced at12 inches (30.48 centimeters) center to center?

HAND TOOLS AND EQUIPMENT

❏ Are all tools and equipment (both companyand employee-owned) used at the workplacein good condition?

❏ Are hand tools, such as chisels, punches, etc.,which develop mushroomed heads duringuse, reconditioned or replaced as necessary?

❏ Are broken or fractured handles on hammers,axes and similar equipment replaced promptly?

❏ Are worn or bent wrenches replaced?

❏ Are appropriate handles used on files and sim-ilar tools?

❏ Are employees aware of hazards caused byfaulty or improperly used hand tools?

❏ Are appropriate safety glasses, face shields,etc., used while using hand tools or equip-ment that might produce flying materials or besubject to breakage?

❏ Are jacks checked periodically to ensure theyare in good operating condition?

❏ Are tool handles wedged tightly into the headsof all tools?

❏ Are tool cutting edges kept sharp so the toolwill move smoothly without binding or skip-ping?

❏ Are tools stored in a dry, secure locationwhere they cannot be tampered with?

❏ Is eye and face protection used when drivinghardened or tempered studs or nails?

PORTABLE (POWER OPERATED) TOOLS

AND EQUIPMENT

❏ Are grinders, saws and similar equipment pro-vided with appropriate safety guards?

❏ Are power tools used with proper shields,guards, or attachments, as recommended bythe manufacturer?

❏ Are portable circular saws equipped withguards above and below the base shoe?

❏ Are circular saw guards checked to ensure thatthey are not wedged up, leaving the lowerportion of the blade unguarded?

❏ Are rotating or moving parts of equipmentguarded to prevent physical contact?

❏ Are all cord-connected, electrically operatedtools and equipment effectively grounded orof the approved double insulated type?

❏ Are effective guards in place over belts, pul-leys, chains and sprockets on equipment suchas concrete mixers, air compressors, etc.?

❏ Are portable fans provided with full guards orscreens having openings 1/2 inch (1.2700 cen-timeters) or less?

❏ Is hoisting equipment available and used forlifting heavy objects, and are hoist ratings andcharacteristics appropriate for the task?

❏ Are ground-fault circuit interrupters providedon all temporary electrical 15 and 20 amperecircuits used during periods of construction?

❏ Are pneumatic and hydraulic hoses on power-operated tools checked regularly for deteriora-tion or damage?

ABRASIVE WHEEL EQUIPMENT GRINDERS

❏ Is the work rest used and kept adjusted to within1/8 inch (0.3175 centimeter) of the wheel?

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❏ Are power-actuated tools inspected for ob-structions or defects each day before use?

❏ Do power-actuated tool operators have anduse appropriate PPE such as hard hats, safetygoggles, safety shoes and ear protectors?

MACHINE GUARDING

❏ Is there a training program to instruct employ-ees on safe methods of machine operation?

❏ Is there adequate supervision to ensure thatemployees are following safe machine operat-ing procedures?

❏ Is there a regular program of safety inspectionof machinery and equipment?

❏ Is all machinery and equipment kept clean andproperly maintained?

❏ Is sufficient clearance provided around andbetween machines to allow for safe opera-tions, set up and servicing, material handlingand waste removal?

❏ Is equipment and machinery securely placedand anchored to prevent tipping or othermovement that could result in personal injury?

❏ Is there a power shut-off switch within reach ofthe operator’s position at each machine?

❏ Can electric power to each machine be lockedout for maintenance, repair, or security?

❏ Are the noncurrent-carrying metal parts ofelectrically operated machines bonded andgrounded?

❏ Are foot-operated switches guarded or ar-ranged to prevent accidental actuation by per-sonnel or falling objects?

❏ Are manually operated valves and switchescontrolling the operation of equipment andmachines clearly identified and readily acces-sible?

❏ Are all emergency stop buttons colored red?

❏ Are all pulleys and belts within 7 feet (2.1336meters) of the floor or working level properlyguarded?

❏ Are all moving chains and gears properlyguarded?

❏ Is the adjustable tongue on the top side of thegrinder used and kept adjusted to within 1/4inch (0.6350 centimeters) of the wheel?

❏ Do side guards cover the spindle, nut andflange and 75 percent of the wheel diameter?

❏ Are bench and pedestal grinders permanentlymounted?

❏ Are goggles or face shields always worn whengrinding?

❏ Is the maximum revolutions per minute (rpm)rating of each abrasive wheel compatible withthe rpm rating of the grinder motor?

❏ Are fixed or permanently mounted grindersconnected to their electrical supply systemwith metallic conduit or other permanentwiring method?

❏ Does each grinder have an individual on andoff control switch?

❏ Is each electrically operated grinder effectivelygrounded?

❏ Are new abrasive wheels visually inspectedand ring tested before they are mounted?

❏ Are dust collectors and powered exhausts pro-vided on grinders used in operations that pro-duce large amounts of dust?

❏ Are splash guards mounted on grinders thatuse coolant to prevent the coolant from reach-ing employees?

❏ Is cleanliness maintained around grinders?

POWER-ACTUATED TOOLS

❏ Are employees who operate power-actuatedtools trained in their use and required to carrya valid operator’s card?

❏ Is each power-actuated tool stored in its ownlocked container when not being used?

❏ Is a sign at least 7 inches (17.78 centimeters)by 10 inches (25.40 centimeters) with bold facetype reading “POWER-ACTUATED TOOL INUSE” conspicuously posted when the tool isbeing used?

❏ Are power-actuated tools left unloaded untilthey are ready to be used?

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❏ Are splash guards mounted on machines thatuse coolant to prevent the coolant from reach-ing employees?

❏ Are methods provided to protect the operatorand other employees in the machine areafrom hazards created at the point of operation,ingoing nip points, rotating parts, flying chipsand sparks?

❏ Are machine guards secure and arranged sothey do not cause a hazard while in use?

❏ If special hand tools are used for placing andremoving material, do they protect the opera-tor’s hands?

❏ Are revolving drums, barrels and containersguarded by an enclosure that is interlockedwith the drive mechanism so that revolutioncannot occur unless the guard enclosure is inplace?

❏ Do arbors and mandrels have firm and securebearings, and are they free from play?

❏ Are provisions made to prevent machinesfrom automatically starting when power isrestored after a power failure or shutdown?

❏ Are machines constructed so as to be freefrom excessive vibration when the largest sizetool is mounted and run at full speed?

❏ If machinery is cleaned with compressed air, isair pressure controlled and PPE or other safe-guards utilized to protect operators and otherworkers from eye and body injury?

❏ Are fan blades protected with a guard havingopenings no larger than l/2 inch (1.2700 cen-timeters) when operating within 7 feet (2.1336meters) of the floor?

❏ Are saws used for ripping equipped with anti-kickback devices and spreaders?

❏ Are radial arm saws so arranged that the cut-ting head will gently return to the back of thetable when released?

LOCKOUT/TAGOUT PROCEDURES

❏ Is all machinery or equipment capable of move-ment required to be de-energized or disengagedand blocked or locked out during cleaning, serv-icing, adjusting, or setting up operations?

❏ If the power disconnect for equipment doesnot also disconnect the electrical control cir-cuit, are the appropriate electrical enclosuresidentified and is a means provided to ensurethat the control circuit can also be disconnect-ed and locked out?

❏ Is the locking out of control circuits instead oflocking out main power disconnects prohibited?

❏ Are all equipment control valve handles pro-vided with a means for locking out?

❏ Does the lockout procedure require that storedenergy (mechanical, hydraulic, air, etc.) be re-leased or blocked before equipment is lockedout for repairs?

❏ Are appropriate employees provided with indi-vidually keyed personal safety locks?

❏ Are employees required to keep personal con-trol of their key(s) while they have safety locksin use?

❏ Is it required that only the employee exposedto the hazard can place or remove the safetylock?

❏ Is it required that employees check the safetyof the lockout by attempting a startup aftermaking sure no one is exposed?

❏ Are employees instructed to always push thecontrol circuit stop button prior to re-energiz-ing the main power switch?

❏ Is there a means provided to identify any or allemployees who are working on locked-outequipment by their locks or accompanyingtags?

❏ Are a sufficient number of accident preventionsigns or tags and safety padlocks provided forany reasonably foreseeable repair emergency?

❏ When machine operations, configuration, orsize require an operator to leave the controlstation and part of the machine could move ifaccidentally activated, is the part required tobe separately locked out or blocked?

❏ If equipment or lines cannot be shut down,locked out and tagged, is a safe job procedureestablished and rigidly followed?

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❏ Is red used to identify the acetylene (and otherfuel-gas) hose, green for the oxygen hose andblack for inert gas and air hoses?

❏ Are pressure-reducing regulators used only forthe gas and pressures for which they are in-tended?

❏ Is open circuit (no-load) voltage of arc weldingand cutting machines as low as possible andnot in excess of the recommended limits?

❏ Under wet conditions, are automatic controlsfor reducing no-load voltage used?

❏ Is grounding of the machine frame and safetyground connections of portable machineschecked periodically?

❏ Are electrodes removed from the holderswhen not in use?

❏ Is it required that electric power to the welderbe shut off when no one is in attendance?

❏ Is suitable fire extinguishing equipment avail-able for immediate use?

❏ Is the welder forbidden to coil or loop weldingelectrode cable around his body?

❏ Are wet machines thoroughly dried and testedbefore use?

❏ Are work and electrode lead cables frequentlyinspected for wear and damage, and replacedwhen needed?

❏ Are cable connectors adequately insulated?

❏ When the object to be welded cannot bemoved and fire hazards cannot be removed,are shields used to confine heat, sparks andslag?

❏ Are fire watchers assigned when welding orcutting is performed in locations where a seri-ous fire might develop?

❏ Are combustible floors kept wet, covered withdamp sand, or protected by fire-resistantshields?

❏ Are personnel protected from possible electri-cal shock when floors are wet?

❏ Are precautions taken to protect combustibleson the other side of metal walls when weldingis underway?

WELDING, CUTTING AND BRAZING

❏ Are only authorized and trained personnel per-mitted to use welding, cutting, or brazingequipment?

❏ Does each operator have a copy of and followthe appropriate operating instructions?

❏ Are compressed gas cylinders regularly exam-ined for obvious signs of defects, deep rusting,or leakage?

❏ Is care used in handling and storage of cylin-ders, safety valves, relief valves, etc., to pre-vent damage?

❏ Are precautions taken to prevent the mixtureof air or oxygen with flammable gases, exceptat a burner or in a standard torch?

❏ Are only approved apparatuses (torches, regu-lators, pressure reducing valves, acetylenegenerators, manifolds) used?

❏ Are cylinders kept away from sources of heatand elevators, stairs, or gangways?

❏ Is it prohibited to use cylinders as rollers orsupports?

❏ Are empty cylinders appropriately marked andtheir valves closed?

❏ Are signs posted reading “DANGER, NOSMOKING, MATCHES, OR OPEN LIGHTS,” orthe equivalent?

❏ Are cylinders, cylinder valves, couplings, regu-lators, hoses and apparatuses kept free of oilyor greasy substances?

❏ Is care taken not to drop or strike cylinders?

❏ Are regulators removed and valve-protectioncaps put in place before moving cylinders,unless they are secured on special trucks?

❏ Do cylinders without fixed wheels have keys,handles, or non-adjustable wrenches on stemvalves when in service?

❏ Are liquefied gases stored and shipped valve-end up with valve covers in place?

❏ Are employees trained never to crack a fuelgas cylinder valve near sources of ignition?

❏ Before a regulator is removed, is the valveclosed and gas released?

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❏ Are used drums, barrels, tanks and other con-tainers thoroughly cleaned of substances thatcould explode, ignite, or produce toxic vaporsbefore hot work begins?

❏ Do eye protection, helmets, hand shields andgoggles meet appropriate standards?

❏ Are employees exposed to the hazards createdby welding, cutting, or brazing operations pro-tected with PPE and clothing?

❏ Is a check made for adequate ventilation inand where welding or cutting is performed?

❏ When working in confined places, are environ-mental monitoring tests done and means pro-vided for quick removal of welders in case ofan emergency?

COMPRESSORS AND COMPRESSED AIR

❏ Are compressors equipped with pressure reliefvalves and pressure gauges?

❏ Are compressor air intakes installed andequipped so as to ensure that only clean,uncontaminated air enters the compressor?

❏ Are air filters installed on the compressorintake?

❏ Are compressors operated and lubricated inaccordance with the manufacturer’s recom-mendations?

❏ Are safety devices on compressed air systemschecked frequently?

❏ Before a compressor’s pressure system is re-paired, is the pressure bled off and the systemlocked out?

❏ Are signs posted to warn of the automaticstarting feature of the compressors?

❏ Is the belt drive system totally enclosed to pro-vide protection for the front, back, top andsides?

❏ Are employees strictly prohibited from direct-ing compressed air towards a person?

❏ Are employees prohibited from using highlycompressed air for cleaning purposes?

❏ When compressed air is used to clean clothing,are employees trained to reduce the pressure toless than 10 pounds per square inch (psi)?

❏ When using compressed air for cleaning, doemployees wear protective chip guarding andPPE?

❏ Are safety chains or other suitable lockingdevices used at couplings of high-pressurehose lines where a connection failure wouldcreate a hazard?

❏ Before compressed air is used to empty con-tainers of liquid, is the safe working pressureof the container checked?

❏ When compressed air is used with abrasiveblast cleaning equipment, is the operatingvalve a type that must be held open manually?

❏ When compressed air is used to inflate autotires, are a clip-on chuck and an inline regula-tor preset to 40 psi required?

❏ Are employees prohibited from using com-pressed air to clean up or move combustibledust if such action could cause the dust to besuspended in the air and cause a fire or explo-sion hazard?

COMPRESSORS/AIR RECEIVERS

❏ Is every receiver equipped with a pressuregauge and one or more automatic, spring-loaded safety valves?

❏ Is the total relieving capacity of the safetyvalve able to prevent pressure in the receiverfrom exceeding the maximum allowable work-ing pressure of the receiver by more than 10percent?

❏ Is every air receiver provided with a drain pipeand valve at the lowest point for the removalof accumulated oil and water?

❏ Are compressed air receivers periodicallydrained of moisture and oil?

❏ Are all safety valves tested at regular intervalsto determine whether they are in good operat-ing condition?

❏ Is there a current operating permit?

❏ Is the inlet of air receivers and piping systemskept free of accumulated oil and carbonaceousmaterials?

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❏ Is the rated load of each hoist legibly markedand visible to the operator?

❏ Are stops provided at the safe limits of travelfor trolley hoists?

❏ Are the controls of hoists plainly marked toindicate the direction of travel or motion?

❏ Is each cage-controlled hoist equipped with aneffective warning device?

❏ Are close-fitting guards or other suitable de-vices installed on each hoist to ensure thathoist ropes will be maintained in the sheavegrooves?

❏ Are all hoist chains or ropes long enough tohandle the full range of movement of theapplication while maintaining two full wrapsaround the drum at all times?

❏ Are guards provided for nip points or contactpoints between hoist ropes and sheaves per-manently located within 7 feet (2.1336 meters)of the floor, ground, or working platform?

❏ Are employees prohibited from using chains orrope slings that are kinked or twisted and pro-hibited from using the hoist rope or chain wrap-ped around the load as a substitute for a sling?

❏ Is the operator instructed to avoid carryingloads above people?

INDUSTRIAL TRUCKS - FORKLIFTS

❏ Are employees properly trained in the use ofthe type of industrial truck they operate?

❏ Are only trained personnel allowed to operateindustrial trucks?

❏ Is substantial overhead protective equipmentprovided on high lift rider equipment?

❏ Are the required lift truck operating rules post-ed and enforced?

❏ Is directional lighting provided on each indus-trial truck that operates in an area with lessthan 2 footcandles per square foot of generallighting?

❏ Does each industrial truck have a warninghorn, whistle, gong, or other device that canbe clearly heard above normal noise in theareas where it is operated?

COMPRESSED GAS CYLINDERS

❏ Are cylinders with a water weight capacityover 30 pounds (13.6 kilograms) equippedwith a means to connect a valve protectordevice, or with a collar or recess to protect the valve?

❏ Are cylinders legibly marked to clearly identifythe type of gas?

❏ Are compressed gas cylinders stored in areasprotected from external heat sources such asflame impingement, intense radiant heat, elec-tric arcs, or high-temperature lines?

❏ Are cylinders located or stored in areas wherethey will not be damaged by passing or fallingobjects or subject to tampering by unautho-rized persons?

❏ Are cylinders stored or transported in a man-ner to prevent them from creating a hazard bytipping, falling, or rolling?

❏ Are cylinders containing liquefied fuel gasstored or transported in a position so that thesafety relief device is always in direct contactwith the vapor space in the cylinder?

❏ Are valve protectors always placed on cylin-ders when the cylinders are not in use or con-nected for use?

❏ Are all valves closed off before a cylinder ismoved, when the cylinder is empty and at thecompletion of each job?

❏ Are low-pressure fuel gas cylinders checkedperiodically for corrosion, general distortion,cracks, or any other defect that might indicatea weakness or render them unfit for service?

❏ Does the periodic check of low-pressure fuelgas cylinders include a close inspection of thecylinders’ bottoms?

HOIST AND AUXILIARY EQUIPMENT

❏ Is each overhead electric hoist equipped with alimit device to stop the hook at its highest andlowest point of safe travel?

❏ Will each hoist automatically stop and holdany load up to 125 percent of its rated load ifits actuating force is removed?

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❏ Are the brakes on each industrial truck capableof bringing the vehicle to a complete and safestop when fully loaded?

❏ Does the parking brake of the industrial truckprevent the vehicle from moving when unat-tended?

❏ Are industrial trucks that operate where flam-mable gases, vapors, combustible dust, orignitable fibers may be present approved forsuch locations?

❏ Are motorized hand and hand/rider trucksdesigned so that the brakes are applied andpower to the drive motor shuts off when theoperator releases his or her grip on the devicethat controls the truck’s travel?

❏ Are industrial trucks with internal combustionengines that are operated in buildings orenclosed areas carefully checked to ensurethat such operations do not cause harmfulconcentrations of dangerous gases or fumes?

❏ Are safe distances maintained from the edgesof elevated ramps and platforms?

❏ Are employees prohibited from standing orpassing under elevated portions of trucks,whether loaded or empty?

❏ Are unauthorized employees prohibited fromriding on trucks?

❏ Are operators prohibited from driving up toanyone standing in front of a fixed object?

❏ Are arms and legs kept inside the runninglines of the truck?

❏ Are loads handled only within the rated capac-ity of the truck?

❏ Are trucks in need of repair removed fromservice immediately?

SPRAYING OPERATIONS

❏ Is adequate ventilation provided before spray-ing operations are started?

❏ Is mechanical ventilation provided when spray-ing operations are performed in enclosed areas?

❏ When mechanical ventilation is provided dur-ing spraying operations, is it so arranged thatit will not circulate the contaminated air?

❏ Is the spray area free of hot surfaces and atleast 20 feet (6.096 meters) from flames,sparks, operating electrical motors and otherignition sources?

❏ Are portable lamps used to illuminate sprayareas suitable for use in a hazardous location?

❏ Is approved respiratory equipment providedand used when appropriate during sprayingoperations?

❏ Do solvents used for cleaning have a flashpoint to 100 degrees Fahrenheit (deg. F) ormore?

❏ Are fire control sprinkler heads kept clean?

❏ Are “NO SMOKING” signs posted in sprayareas, paint rooms, paint booths and paintstorage areas?

❏ Is the spray area kept clean of combustibleresidue?

❏ Are spray booths constructed of metal,masonry, or other substantial noncombusti-ble material?

❏ Are spray booth floors and baffles noncom-bustible and easily cleaned?

❏ Is infrared drying apparatus kept out of thespray area during spraying operations and isthe spray booth completely ventilated beforeusing the drying apparatus?

❏ Is the electric drying apparatus properlygrounded?

❏ Are lighting fixtures for spray booths locatedoutside the booth with the interior lightedthrough sealed clear panels?

❏ Are the electric motors for exhaust fans placedoutside booths or ducts?

❏ Are belts and pulleys inside the booth fullyenclosed?

❏ Do ducts have access doors to allow cleaning?

❏ Do all drying spaces have adequate ventilation?

ENTERING CONFINED SPACES

❏ Are confined spaces thoroughly emptied ofany corrosive or hazardous substances, suchas acids or caustics, before entry?

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equipment such as salamanders, torches, fur-naces, etc., in a confined space, is sufficient airprovided to assure combustion without reduc-ing the oxygen concentration of the atmos-phere below 19.5 percent by volume?

❏ Whenever combustion-type equipment is usedin a confined space, are provisions made toensure the exhaust gases are vented outsideof the enclosure?

❏ Is each confined space checked for decayingvegetation or animal matter which may pro-duce methane?

❏ Is the confined space checked for possibleindustrial waste which could contain toxicproperties?

❏ If the confined space is below ground andnear areas where motor vehicles will be oper-ating, is it possible for vehicle exhaust or car-bon monoxide to enter the space?

ENVIRONMENTAL CONTROLS

❏ Are all work areas properly illuminated?

❏ Are employees instructed in proper first aidand other emergency procedures?

❏ Are hazardous substances, blood and otherpotentially infectious materials, which maycause harm by inhalation, ingestion, or skinabsorption or contact, identified?

❏ Are employees aware of the hazards involvedwith the various chemicals they may be ex-posed to in their work environment, such asammonia, chlorine, epoxies, caustics, etc.?

❏ Is employee exposure to chemicals in theworkplace kept within acceptable levels?

❏ Can a less harmful method or product beused?

❏ Is the work area ventilation system appropri-ate for the work performed?

❏ Are spray painting operations performed inspray rooms or booths equipped with anappropriate exhaust system?

❏ Is employee exposure to welding fumes con-trolled by ventilation, use of respirators, expo-sure time limits, or other means?

❏ Are all lines to a confined space that containinert, toxic, flammable, or corrosive materialsvalved off and blanked or disconnected andseparated before entry?

❏ Are all impellers, agitators, or other movingparts and equipment inside confined spaceslocked out if they present a hazard?

❏ Is either natural or mechanical ventilation pro-vided prior to confined space entry?

❏ Are appropriate atmospheric tests performedto check for oxygen deficiency, toxic sub-stances and explosive concentrations in theconfined space before entry?

❏ Is adequate illumination provided for the workto be performed in the confined space?

❏ Is the atmosphere inside the confined spacefrequently tested or continuously monitoredduring work?

❏ Is there a trained and equipped standbyemployee positioned outside the confinedspace, whose sole responsibility is to watchthe work in progress, sound an alarm if neces-sary and render assistance?

❏ Is the standby employee appropriately trainedand equipped to handle an emergency?

❏ Are employees prohibited from entering theconfined space without lifelines and respira-tory equipment if there is any question as tothe cause of an emergency?

❏ Is approved respiratory equipment required ifthe atmosphere inside the confined space can-not be made acceptable?

❏ Is all portable electrical equipment used insideconfined spaces either grounded and insulatedor equipped with ground fault protection?

❏ Are compressed gas bottles forbidden insidethe confined space?

❏ Before gas welding or burning is started in aconfined space, are hoses checked for leaks,torches lighted only outside the confined areaand the confined area tested for an explosiveatmosphere each time before a lighted torch istaken into the confined space?

❏ If employees will be using oxygen-consuming

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❏ Are welders and other nearby workers provid-ed with flash shields during welding opera-tions?

❏ If forklifts and other vehicles are used in build-ings or other enclosed areas, are the carbonmonoxide levels kept below maximum accept-able concentration?

❏ Has there been a determination that noise lev-els in the facilities are within acceptable lev-els?

❏ Are steps being taken to use engineering con-trols to reduce excessive noise levels?

❏ Are proper precautions being taken when han-dling asbestos and other fibrous materials?

❏ Are caution labels and signs used to warn ofhazardous substances (e.g., asbestos) and bio-hazards (e.g., bloodborne pathogens)?

❏ Are wet methods used, when practicable, toprevent the emission of airborne asbestosfibers, silica dust and similar hazardous mate-rials?

❏ Are engineering controls examined and main-tained or replaced on a scheduled basis?

❏ Is vacuuming with appropriate equipmentused whenever possible rather than blowingor sweeping dust?

❏ Are grinders, saws and other machines thatproduce respirable dusts vented to an industri-al collector or central exhaust system?

❏ Are all local exhaust ventilation systems de-signed to provide sufficient air flow and vol-ume for the application, and are ducts notplugged and belts not slipping?

❏ Is PPE provided, used and maintained wherev-er required?

❏ Are there written standard operating proce-dures for the selection and use of respiratorswhere needed?

❏ Are restrooms and washrooms kept clean andsanitary?

❏ Is all water provided for drinking, washing andcooking potable?

❏ Are all outlets for water that is not suitable fordrinking clearly identified?

❏ Are employees’ physical capacities assessedbefore they are assigned to jobs requiringheavy work?

❏ Are employees instructed in the proper man-ner for lifting heavy objects?

❏ Where heat is a problem, have all fixed workareas been provided with spot cooling or airconditioning?

❏ Are employees screened before assignment toareas of high heat to determine if their healthmight make them more susceptible to havingan adverse reaction?

❏ Are employees working on streets and road-ways who are exposed to the hazards of trafficrequired to wear bright colored (traffic orange)warning vests?

❏ Are exhaust stacks and air intakes located sothat nearby contaminated air will not be re-circulated within a building or other enclos-ed area?

❏ Is equipment producing ultraviolet radiationproperly shielded?

❏ Are universal precautions observed whereoccupational exposure to blood or other po-tentially infectious materials can occur and inall instances where differentiation of types ofbody fluids or potentially infectious materialsis difficult or impossible?

FLAMMABLE AND COMBUSTIBLE MATERIALS

❏ Are combustible scrap, debris and wastematerials (oily rags, etc.) stored in coveredmetal receptacles and promptly removed fromthe worksite?

❏ Is proper storage practiced to minimize the riskof fire, including spontaneous combustion?

❏ Are approved containers and tanks used tostore and handle flammable and combustibleliquids?

❏ Are all connections on drums and combustibleliquid piping, vapor and liquid tight?

❏ Are all flammable liquids kept in closed con-tainers when not in use (e.g., parts cleaningtanks, pans, etc.)?

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❏ Where sprinkler systems are permanentlyinstalled, are the nozzle heads so directed orarranged that water will not be sprayed intooperating electrical switchboards and equip-ment?

❏ Are safety cans used for dispensing flammableor combustible liquids at the point of use?

❏ Are all spills of flammable or combustible liq-uids cleaned up promptly?

❏ Are storage tanks adequately vented to pre-vent the development of excessive vacuum orpressure as a result of filling, emptying, oratmosphere temperature changes?

❏ Are storage tanks equipped with emergencyventing that will relieve excessive internalpressure caused by fire exposure?

❏ Are rules enforced in areas involving storageand use of hazardous materials?

HAZARDOUS CHEMICAL EXPOSURE

❏ Are employees aware of the potential hazardsand trained in safe handling practices for situ-ations involving various chemicals stored orused in the workplace such as acids, bases,caustics, epoxies, phenols, etc.?

❏ Is employee exposure to chemicals kept withinacceptable levels?

❏ Are eye-wash fountains and safety showersprovided in areas where corrosive chemicalsare handled?

❏ Are all containers, such as vats, storage tanks,etc., labeled as to their contents, e.g., “CAUS-TICS”?

❏ Are all employees required to use personalprotective clothing and equipment when han-dling chemicals (gloves, eye protection, respi-rators, etc.)?

❏ Are flammable or toxic chemicals kept inclosed containers when not in use?

❏ Are chemical piping systems clearly marked asto their content?

❏ Where corrosive liquids are frequently handledin open containers or drawn from storage ves-sels or pipelines, are adequate means readily

❏ Are bulk drums of flammable liquids groundedand bonded to containers during dispensing?

❏ Do storage rooms for flammable and com-bustible liquids have explosion-proof lightsand mechanical or gravity ventilation?

❏ Is liquefied petroleum gas stored, handled and used in accordance with safe practicesand standards?

❏ Are “NO SMOKING” signs posted on liquefiedpetroleum gas tanks and in areas where flam-mable or combustible materials are used orstored?

❏ Are liquefied petroleum storage tanks guardedto prevent damage from vehicles?

❏ Are all solvent wastes and flammable liquidskept in fire-resistant, covered containers untilthey are removed from the worksite?

❏ Is vacuuming used whenever possible ratherthan blowing or sweeping combustible dust?

❏ Are firm separators placed between containersof combustibles or flammables that are stack-ed one upon another to ensure their supportand stability?

❏ Are fuel gas cylinders and oxygen cylindersseparated by distance and fire-resistant barri-ers while in storage?

❏ Are fire extinguishers selected and providedfor the types of materials in the areas wherethey are to be used?

Class A - Ordinary combustible material fires.

Class B - Flammable liquid, gas or grease fires.

Class C - Energized-electrical equipment fires.

❏ Are appropriate fire extinguishers mountedwithin 75 feet (22.86 meters) of outside areascontaining flammable liquids and within 10feet (3.048 meters) of any inside storage areafor such materials?

❏ Are extinguishers free from obstructions orblockage?

❏ Are all extinguishers serviced, maintained andtagged at intervals not to exceed one year?

❏ Are all extinguishers fully charged and in theirdesignated places?

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available for neutralizing or disposing of spills oroverflows and performed properly and safely?

❏ Are standard operating procedures establishedand are they being followed when cleaning upchemical spills?

❏ Are respirators stored in a convenient, cleanand sanitary location, and are they adequatefor emergencies?

❏ Are employees prohibited from eating in areaswhere hazardous chemicals are present?

❏ Is PPE used and maintained whenever neces-sary?

❏ Are there written standard operating proce-dures for the selection and use of respiratorswhere needed?

❏ If you have a respirator protection program,are your employees instructed on the correctusage and limitations of the respirators? Are the respirators National Institute forOccupational Safety and Health (NIOSH)-approved for this particular application? Are they regularly inspected, cleaned, sani-tized and maintained?

❏ If hazardous substances are used in your pro-cesses, do you have a medical or biologicalmonitoring system in operation?

❏ Are you familiar with the threshold limit val-ues or permissible exposure limits of airbornecontaminants and physical agents used inyour workplace?

❏ Have appropriate control procedures beeninstituted for hazardous materials, includingsafe handling practices and the use of respira-tors and ventilation systems?

❏ Whenever possible, are hazardous substanceshandled in properly designed and exhaustedbooths or similar locations?

❏ Do you use general dilution or local exhaustventilation systems to control dusts, vapors,gases, fumes, smoke, solvents, or mists thatmay be generated in your workplace?

❏ Is operational ventilation equipment providedfor removal of contaminants from productiongrinding, buffing, spray painting, and/or vapordegreasing?

❏ Do employees complain about dizziness,headaches, nausea, irritation, or other factorsof discomfort when they use solvents or otherchemicals?

❏ Is there a dermatitis problem? Do employeescomplain about dryness, irritation, or sensitiza-tion of the skin?

❏ Have you considered having an industrialhygienist or environmental health specialistevaluate your operation?

❏ If internal combustion engines are used, is car-bon monoxide kept within acceptable levels?

❏ Is vacuuming used rather than blowing orsweeping dust whenever possible forcleanup?

❏ Are materials that give off toxic, asphyxiant,suffocating, or anesthetic fumes stored inremote or isolated locations when not in use?

HAZARDOUS SUBSTANCES COMMUNICATION

❏ Is there a list of hazardous substances used inyour workplace and an MSDS readily availablefor each hazardous substance used?

❏ Is there a current written exposure control planfor occupational exposure to bloodbornepathogens and other potentially infectiousmaterials, where applicable?

❏ Is there a written hazard communication pro-gram dealing with MSDSs, labeling andemployee training?

❏ Is each container for a hazardous substance(i.e., vats, bottles, storage tanks, etc.) labeledwith product identity and a hazard warning(communication of the specific health hazardsand physical hazards)?

❏ Is there an employee training program for haz-ardous substances that includes:

■ an explanation of what an MSDS is and howto use and obtain one;

■ MSDS contents for each hazardous substanceor class of substances;

■ explanation of “A Right to Know”;

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follow-up that will be made available;

■ information on post-exposure evaluations andfollow-up; and

■ an explanation of signs, labels and color coding.

❏ Are employees trained in:

■ how to recognize tasks that might result inoccupational exposure;

■ how to use work practice, engineering con-trols and PPE, and their limitations;

■ how to obtain information on the types, selec-tion, proper use, location, removal, handling,decontamination and disposal of PPE; and

■ who to contact and what to do in an emer-gency.

ELECTRICAL

❏ Do you require compliance with OSHA stan-dards for all contract electrical work?

❏ Are all employees required to report any obvi-ous hazard to life or property in connectionwith electrical equipment or lines as soon aspossible?

❏ Are employees instructed to make preliminaryinspections and/or appropriate tests to deter-mine conditions before starting work on elec-trical equipment or lines?

❏ When electrical equipment or lines are to beserviced, maintained, or adjusted, are neces-sary switches opened, locked out or tagged,whenever possible?

❏ Are portable electrical tools and equipmentgrounded or of the double insulated type?

❏ Are electrical appliances such as vacuumcleaners, polishers, vending machines, etc.,grounded?

❏ Do extension cords have a grounding con-ductor?

❏ Are multiple plug adaptors prohibited?

❏ Are ground-fault circuit interrupters installedon each temporary 15 or 20 ampere, 120 voltalternating current (AC) circuit at locations

■ identification of where an employee can seethe written hazard communication program;

■ location of physical and health hazards in par-ticular work areas and the specific protectivemeasures to be used; and

■ details of the hazard communication program,including how to use the labeling system andMSDSs.

❏ Does the employee training program on thebloodborne pathogens standard contain thefollowing elements:

■ an accessible copy of the standard and anexplanation of its contents;

■ a general explanation of the epidemiologyand symptoms of bloodborne diseases;

■ an explanation of the modes of transmissionof Bloodborne Pathogens;

■ an explanation of the employer’s exposurecontrol plan and the means by which employ-ees can obtain a copy of the written plan;

■ an explanation of the appropriate methods forrecognizing tasks and the other activities thatmay involve exposure to blood and otherpotentially infectious materials;

■ an explanation of the use and limitations ofmethods that will prevent or reduce exposure,including appropriate engineering controls,work practices and PPE;

■ information on the types, proper use, location,removal, handling, decontamination and dis-posal of PPE;

■ an explanation of the basis for selection ofPPE;

■ information on the hepatitis B vaccine;

■ information on the appropriate actions to takeand persons to contact in an emergency in-volving blood or other potentially infectiousmaterials;

■ an explanation of the procedure to follow if anexposure incident occurs, including the meth-ods of reporting the incident and the medical

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where construction, demolition, modifications,alterations, or excavations are being per-formed?

❏ Are all temporary circuits protected by suitabledisconnecting switches or plug connectors atthe junction with permanent wiring?

❏ Do you have electrical installations in haz-ardous dust or vapor areas? If so, do theymeet the National Electrical Code (NEC) forhazardous locations?

❏ Are exposed wiring and cords with frayed ordeteriorated insulation repaired or replacedpromptly?

❏ Are flexible cords and cables free of splices ortaps?

❏ Are clamps or other securing means providedon flexible cords or cables at plugs, recepta-cles, tools, equipment, etc., and is the cordjacket securely held in place?

❏ Are all cord, cable and raceway connectionsintact and secure?

❏ In wet or damp locations, are electrical toolsand equipment appropriate for the use or loca-tion or otherwise protected?

❏ Is the location of electrical power lines andcables (overhead, underground, under floor,other side of walls, etc.) determined beforedigging, drilling, or similar work is begun?

❏ Are metal measuring tapes, ropes, hand-linesor similar devices with metallic thread woveninto the fabric prohibited where they couldcome in contact with energized parts of equip-ment or circuit conductors?

❏ Is the use of metal ladders prohibited wherethe ladder or the person using the laddercould come in contact with energized parts ofequipment, fixtures, or circuit conductors?

❏ Are all disconnecting switches and circuitbreakers labeled to indicate their use or equip-ment served?

❏ Are disconnecting means always openedbefore fuses are replaced?

❏ Do all interior wiring systems include provi-sions for grounding metal parts of electricalraceways, equipment and enclosures?

❏ Are all electrical raceways and enclosuressecurely fastened in place?

❏ Are all energized parts of electrical circuits andequipment guarded against accidental contactby approved cabinets or enclosures?

❏ Is sufficient access and working space provid-ed and maintained around all electrical equip-ment to permit ready and safe operations andmaintenance?

❏ Are all unused openings (including conduitknockouts) in electrical enclosures and fittingsclosed with appropriate covers, plugs, orplates?

❏ Are electrical enclosures such as switches, re-ceptacles, junction boxes, etc., provided withtight-fitting covers or plates?

❏ Are disconnecting switches for electricalmotors in excess of two horsepower able toopen the circuit when the motor is stalledwithout exploding? (Switches must be horse-power rated equal to or in excess of the motorrating.)

❏ Is low voltage protection provided in the con-trol device of motors driving machines orequipment that could cause injury from inad-vertent starting?

❏ Is each motor disconnecting switch or circuitbreaker located within sight of the motor con-trol device?

❏ Is each motor located within sight of its con-troller or is the controller disconnecting meansable to be locked open or is a separate discon-necting means installed in the circuit withinsight of the motor?

❏ Is the controller for each motor that exceedstwo horsepower rated equal to or above therating of the motor it serves?

❏ Are employees who regularly work on oraround energized electrical equipment or linesinstructed in cardiopulmonary resuscitation(CPR)?

❏ Are employees prohibited from working aloneon energized lines or equipment over 600volts?

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❏ In fueling operations, is there always metalcontact between the container and the fueltank?

❏ Are fueling hoses designed to handle the spe-cific type of fuel?

❏ Are employees prohibited from handling ortransferring gasoline in open containers?

❏ Are open lights, open flames, sparking, or arc-ing equipment prohibited near fueling ortransfer of fuel operations?

❏ Is smoking prohibited in the vicinity of fuelingoperations?

❏ Are fueling operations prohibited in buildingsor other enclosed areas that are not specifical-ly ventilated for this purpose?

❏ Where fueling or transfer of fuel is donethrough a gravity flow system, are the nozzlesself-closing?

IDENTIFICATION OF PIPING SYSTEMS

❏ When nonpotable water is piped through afacility, are outlets or taps posted to alertemployees that the water is unsafe and not tobe used for drinking, washing, or other per-sonal use?

❏ When hazardous substances are transportedthrough above-ground piping, is each pipelineidentified at points where confusion couldintroduce hazards to employees?

❏ When pipelines are identified by color paintedbands or tapes, are the bands or tapes locatedat reasonable intervals and at each outlet,valve, or connection, and are all visible partsof the line so identified?

❏ When pipelines are identified by color, is thecolor code posted at all locations where confu-sion could introduce hazards to employees?

❏ When the contents of pipelines are identifiedby name or name abbreviation, is the informa-tion readily visible on the pipe near each valveor outlet?

❏ When pipelines carrying hazardous substancesare identified by tags, are the tags constructedof durable materials, the message printed

NOISE

❏ Are there areas in the workplace where contin-uous noise levels exceed 85 decibels?

❏ Is there an ongoing preventive health programto educate employees in safe levels of noise,exposures, effects of noise on their health andthe use of personal protection?

❏ Have work areas where noise levels makevoice communication between employees dif-ficult been identified and posted?

❏ Are noise levels measured with a sound levelmeter or an octave band analyzer and arerecords being kept?

❏ Have engineering controls been used toreduce excessive noise levels? Where engi-neering controls are determined to be infeasi-ble, are administrative controls (i.e., workerrotation) being used to minimize individualemployee exposure to noise?

❏ Is approved hearing protective equipment(noise attenuating devices) available to everyemployee working in noisy areas?

❏ Have you tried isolating noisy machinery fromthe rest of your operation?

❏ If you use ear protectors, are employees prop-erly fitted and instructed in their use?

❏ Are employees in high noise areas given peri-odic audiometric testing to ensure that youhave an effective hearing protection system?

FUELING

❏ Are employees prohibited from fueling aninternal combustion engine with a flammableliquid while the engine is running?

❏ Are fueling operations performed to minimizespillage?

❏ When spillage occurs during fueling opera-tions, is the spilled fuel washed away com-pletely, evaporated, or are other measurestaken to control vapors before restarting theengine?

❏ Are fuel tank caps replaced and securedbefore starting the engine?

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clearly and permanently, and are tags installedat each valve or outlet?

❏ When pipelines are heated by electricity,steam, or other external source, are suitablewarning signs or tags placed at unions, valves,or other serviceable parts of the system?

MATERIALS HANDLING

❏ Is there safe clearance for equipment throughaisles and doorways?

❏ Are aisleways permanently marked and keptclear to allow unhindered passage?

❏ Are motorized vehicles and mechanized equip-ment inspected daily or prior to use?

❏ Are vehicles shut off and brakes set prior toloading or unloading?

❏ Are containers of liquid combustibles or flam-mables, when stacked while being moved,always protected by dunnage (packing materi-al) sufficient to provide stability?

❏ Are dock boards (bridge plates) used whenloading or unloading operations are takingplace between vehicles and docks?

❏ Are trucks and trailers secured from move-ment during loading and unloading opera-tions?

❏ Are dock plates and loading ramps construct-ed and maintained with sufficient strength tosupport imposed loading?

❏ Are hand trucks maintained in safe operatingcondition?

❏ Are chutes equipped with sideboards of suffi-cient height to prevent the materials beinghandled from falling off?

❏ Are chutes and gravity roller sections firmlyplaced or secured to prevent displacement?

❏ Are provisions made to brake the movementof the handled materials at the delivery end ofrollers or chutes?

❏ Are pallets usually inspected before beingloaded or moved?

❏ Are safety latches and other devices beingused to prevent slippage of materials off ofhoisting hooks?

❏ Are securing chains, ropes, chockers, or slingsadequate for the job?

❏ Are provisions made to ensure that no one isbelow when hoisting material or equipment?

❏ Are MSDSs available to employees handlinghazardous substances?

TRANSPORTING EMPLOYEES AND MATERIALS

❏ Do employees who operate vehicles on publicthoroughfares have valid operator’s licenses?

❏ When seven or more employees are regularlytransported in a van, bus, or truck, is the oper-ator’s license appropriate for the class of vehi-cle being driven and are there enough seats?

❏ Are vehicles used to transport employeesequipped with lamps, brakes, horns, mirrors,windshields and turn signals, and are they ingood repair?

❏ Are transport vehicles provided with handrails,steps, stirrups, or similar devices, placed andarranged to allow employees to safely mountor dismount?

❏ Are employee transport vehicles equipped atall times with at least two reflective-typeflares?

❏ Is a fully charged fire extinguisher, in goodcondition, with at least a 4 B:C rating main-tained in each employee transport vehicle?

❏ When cutting tools or tools with sharp edgesare carried in passenger compartments ofemployee transport vehicles, are they placedin closed boxes or containers that are securedin place?

❏ Are employees prohibited from riding on topof any load that could shift, topple, or other-wise become unstable?

CONTROL OF HARMFUL SUBSTANCES

BY VENTILATION

❏ Is the volume and velocity of air in each ex-haust system sufficient to gather the dusts,fumes, mists, vapors, or gases to be controll-ed, and to convey them to a suitable point ofdisposal?

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❏ When employees are required to change fromstreet clothing into protective clothing, is aclean change room with a separate storagefacility for street and protective clothing pro-vided?

❏ Are employees required to shower and washtheir hair as soon as possible after a knowncontact with a carcinogen has occurred?

❏ When equipment, materials, or other items aretaken into or removed from a carcinogen-reg-ulated area, is it done in a manner that will notcontaminate non-regulated areas or the exter-nal environment?

TIRE INFLATION

❏ Where tires are mounted and/or inflated ondrop center wheels or on wheels with splitrims and/or retainer rings, is a safe practiceprocedure posted and enforced?

❏ Does each tire inflation hose have a clip-onchuck with at least 2.54 inches (6.45 centime-ters) of hose between the chuck and an in-linehand valve and gauge?

❏ Does the tire inflation control valve automati-cally shut off the air flow when the valve isreleased?

❏ Is a tire restraining device such as a cage, rack,or other effective means used while inflatingtires mounted on split rims or rims usingretainer rings?

❏ Are employees prohibited from standingdirectly over or in front of a tire while it isbeing inflated?

❏ Are exhaust inlets, ducts and plenums de-signed, constructed and supported to preventcollapse or failure of any part of the system?

❏ Are clean-out ports or doors provided at inter-vals not to exceed 12 feet (3.6576 meters) in allhorizontal runs of exhaust ducts?

❏ Where two or more different operations arebeing controlled through the same exhaustsystem, could the combination of substancesinvolved create a fire, explosion, or chemicalreaction hazard in the duct?

❏ Is adequate makeup air provided to areaswhere exhaust systems are operating?

❏ Is the source point for makeup air located sothat only clean, fresh air, free of contaminantswill enter the work environment?

❏ Where two or more ventilation systems servea work area, is their operation such that onewill not offset the functions of the other?

SANITIZING EQUIPMENT AND CLOTHING

❏ Is required personal protective clothing orequipment able to be cleaned and disinfectedeasily?

❏ Are employees prohibited from interchangingpersonal protective clothing or equipment,unless it has been properly cleaned?

❏ Are machines and equipment that process,handle, or apply materials that could injureemployees cleaned and/or decontaminatedbefore being overhauled or placed in storage?

❏ Are employees prohibited from smoking oreating in any area where contaminants arepresent that could be injurious if ingested?

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OSHA Assistance

OSHA’S OFFICE OF SMALL BUSINESS ASSISTANCE

OSHA created the Office of Small BusinessAssistance to help small business employersunderstand their safety and health obligations,access compliance information, provide guidanceon regulatory standards, and to educate themabout cost-effective means for ensuring the safetyand health of worksites.

OSHA’s Office of Small Business Assistance canbe contacted by telephone at (202) 693-2220 or bywriting to the U.S. Department of Labor, 200Constitution Avenue, NW, Room N-3700,Washington, DC 20210.

ON-SITE CONSULTATION

Using the free and confidential on-site consulta-tion service largely funded by the Federal OSHA,employers can find out about potential hazards attheir worksites, improve their occupational safetyand health management systems, and even qualifyfor a one-year exemption from routine OSHA in-spections.

The service is delivered at your workplace bystate governments using well-trained professionalstaff. Most consultations take place on-site, thoughlimited services away from the worksite are avail-able.

Primarily targeted for smaller businesses, thissafety and health Consultation Program is com-pletely separate from OSHA’s enforcement efforts.It is also confidential. No inspections are triggeredby using the Consultation Program and no citationsare issued or penalties proposed.

Your name, your firm’s name and any informa-tion you provide about your workplace, plus anyunsafe or unhealthful working conditions that theconsultant uncovers, will not routinely be reportedto the OSHA enforcement staff.

Your only obligation will be to commit to cor-recting serious job safety and health hazards dis-covered -- a commitment that you are expected tomake prior to the actual consultation visit. If haz-ards are discovered, the consultant will work withyou to ensure they are corrected in a reasonabletimeframe agreed upon by all parties.

Getting Started. Since consultation is a volun-tary activity, you must request it. Your telephonecall or letter sets the consulting machinery inmotion. The consultant will discuss your specific

needs and set up a visit date based on the priorityassigned to your request, your work schedule andthe time needed for the consultant to prepare ade-quately to serve you. OSHA encourages a com-plete review of your firm’s safety and health situa-tion; however, if you wish, you may limit the visitto one or more specific problems.

Opening Conference. When the consultantarrives at your worksite for the scheduled visit, heor she will first meet with you in an opening con-ference to briefly review the consultant’s role andthe obligations you incur as an employer.

Walk-through. Together, you and the consultantwill examine conditions in your workplace. OSHAstrongly encourages maximum employee partici-pation in the walk-through. Better informed andalert employees can help you identify and correctpotential injury and illness hazards in your work-place. Talking with employees during the walk-through helps the consultant identify and judge thenature and extent of specific hazards.

The consultant will study your entire workplace,or only those specific operations you designate,and discuss applicable OSHA standards. The con-sultant also will point out other safety or healthrisks which might not be cited under OSHA stan-dards, but which nevertheless may pose safety orhealth risks to your employees. He or she maysuggest and even provide measures such as self-inspection and safety and health training that youand your employees can apply to prevent futurehazardous situations.

A comprehensive consultation also includes: (1)appraisal of all mechanical and environmental haz-ards and physical work practices; (2) appraisal ofthe present job safety and health program or helpin establishing one; (3) a conference with manage-ment on findings; (4) a written report of recommen-dations and agreements; and (5) training and assis-tance with implementing recommendations.

Closing Conference. The consultant will thenreview detailed findings with you in a closing con-ference. You will learn not only what you need toimprove but what you are doing right, as well. Atthat time you can discuss problems, possible solu-tions and abatement periods to eliminate or controlany serious hazards identified during the walk-through.

In rare instances, the consultant may find an“imminent danger” situation during the walk-through. In that case, you must take immediate

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ASSISTANCE IN SAFETY AND HEALTH FOR SMALL BUSINESSES

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changes in working conditions or processes occurthat may introduce new hazards. Employers whomeet these specific SHARP requirements may beremoved from OSHA’s programmed inspection listfor one year.

The on-site consultants will:

■ help you recognize hazards in your workplace,

■ suggest general approaches or options forsolving a safety or health problem,

■ identify kinds of help available if you need fur-ther assistance,

■ provide you with a written report summarizingfindings,

■ assist you in developing or maintaining aneffective safety and health program,

■ provide training and education for you andyour employees,

■ recommend you for a one-year exclusion fromOSHA programmed inspections, once pro-gram criteria are met.

The on-site consultants will not:

■ issue citations or propose penalties for viola-tions of OSHA standards,

■ report possible violations to OSHA enforce-ment staff,

■ guarantee that your workplace will “pass” anOSHA inspection.

For a list of consultation projects in each state,see the OSHA website at www.osha.gov/dcsp/smallbusiness/consult_directory.html

OTHER COOPERATIVE PROGRAMS

Information about OSHA’s different cooperativeprograms is available from any OSHA RegionalOffice, OSHA Area Office, or by contacting OSHA’sDirectorate of Cooperative and State Programs atthe U.S. Department of Labor, Occupational Safetyand Health Administration, 200 ConstitutionAvenue, NW, Room N-3700, Washington, DC 20210,phone (202) 693-2200.

action to protect employees. In certain other situa-tions–those that would be judged a “serious viola-tion” under OSHA criteria–you and the consultantmust develop and agree to a reasonable plan andschedule to eliminate or control that hazard. Theconsultant will offer general approaches and op-tions to you. He or she may also suggest othersources for technical help.

Abatement and Follow-through. Following theclosing conference, the consultant will send you adetailed written report explaining the findings andconfirming any abatement periods agreed upon.The consultant may also contact you from time totime to check your progress. You, of course, mayalways contact him or her for assistance.

Ultimately, OSHA does require hazard abate-ment so that each consultation visit achieves itsobjective–effective employee protection. If you failto eliminate or control identified serious hazards(or an imminent danger) according to the plan andwithin the limits agreed upon or an agreed-uponextension, the situation must be referred from con-sultation to an OSHA enforcement office for appro-priate action. This type of referral is extremely rare.

Benefits. Knowledge of your workplace hazardsand ways to eliminate them can only improve yourown operations–and the management of your firm.You will get professional advice and assistance onthe correction of workplace hazards and benefitfrom on-site training and assistance provided. Theconsultant can help you establish or strengthen anemployee safety and health program, making safe-ty and health activities routine rather than crisis-oriented responses.

In many states, employers may participate inOSHA’s Safety and Health AchievementRecognition Program (SHARP). This program isdesigned to provide incentives and support tosmaller, high-hazard employers to develop, imple-ment and continuously improve effective safetyand health programs at their worksite(s). SHARPprovides recognition of employers who havedemonstrated exemplary achievements in work-place safety and health, beginning with a compre-hensive safety and health consultation visit, correc-tion of all workplace safety and health hazards,adoption and implementation of effective safetyand health management systems, and agreementto request further consultative visits if major

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VOLUNTARY PROTECTION PROGRAMS (VPP)

OSHA’s VPP provide an opportunity for labor,management and government to work togethercooperatively to further the goal of providing effec-tive safety and health protection in the workplace.The VPP grant recognition to worksites that provideor are committed to providing effective protectionfor their employees through implementation ofsystematically managed safety and health pro-grams. The Star Program is for worksites that haveat least one year’s experience with an effectivelyimplemented safety and health program. The MeritProgram is for worksites working toward an effec-tively implemented program. The DemonstrationProgram is for worksites with programs at Starquality but with some aspect of their program thatrequires further study by OSHA. All participantswork in partnership with OSHA and provide mod-els for OSHA and for their industries.

OSHA STRATEGIC PARTNERSHIP PROGRAM (OSPP)

OSPP is designed to enable groups of employ-ers, employees and employee representatives topartner with OSHA and enter into an extended, vol-untary, cooperative relationship in order to encour-age, assist and recognize efforts to eliminate seri-ous hazards and achieve a high level of workersafety and health.

OSHA ALLIANCE PROGRAM

Alliances are goal-oriented written agreementsbetween OSHA and organizations to work togetherto prevent workplace injuries and illnesses. Organ-izations include employers, employees, labor unions,trade or professional groups, educational institu-tions and government agencies. Alliances focus onone or more of the following goals: training andeducation, outreach and communications, and pro-moting the national dialogue on occupational safe-ty and health.

States with Approved PlansThe Occupational Safety and Health Act of 1970

encourages states to develop and operate theirown job safety and health programs. OSHAapproves and monitors state plans and provides upto 50 percent of an approved plan’s operating costs.

Twenty-four states, Puerto Rico and the VirginIslands currently operate approved state plans.

These state plans operate under authority of statelaw and are required to be, in structure and per-formance, “at least as effective as” the FederalOSHA Program. Although many states have adopt-ed standards and procedures identical to Federalstandards, states may have different or additionalrequirements parallel to those described in theFederal program.

To determine which set of standards and regula-tions apply to you, you need to know whether youare covered by a state plan or subject to FederalOSHA. Please visit http://www.oshaslc.gov/fso/osp/index.html, call the OSHA Area Office nearest you,or (800) 321-OSHA to obtain this information.

If you are subject to state enforcement, theOSHA Area Office will refer you to your state officewhich can provide all relevant information, such aswhether the state is using the Federal standards,information on the poster and recordkeepingrequirements, and special services available tosmall businesses. The state office also can provideyou with further assistance, including directing youto the free, on-site consultation services describedabove.

See the list of OSHA-approved state plans atwww.osha.gov.

OSHA Publications

A single free copy of the following materials can beobtained from the OSHA Area or Regional Office,or contact the OSHA Publications Office, U.S.Department of Labor, 200 Constitution Avenue,NW, N-3101, Washington, DC 20210, or call (202)693-1888, or fax (202) 693-2498.

Access to Medical and Exposure Records – OSHA 3110

All About OSHA – OSHA 2056 (Spanish version 3173)

Asbestos Standard for General Industry – OSHA 3095

Consultation Services for the Employer – OSHA 3047

Control of Hazardous Energy (Lockout/Tagout) –OSHA 3120

Emergency Exit Routes Quick Card – OSHA 3183

Employee Workplace Rights – OSHA 3021 (Spanish version 3049)

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Government Printing Office, Superintendent ofDocuments, phone toll-free (866) 512-1800.

Emergencies—For life-threatening situations, call(800) 321-OSHA. Your call will be directed to thenearest OSHA Area or state office for help.

For further information on any OSHA program,contact your nearest OSHA Area or Regional Officeor call (800) 321-OSHA.

Other Sources of Assistance

VOLUNTARY PROTECTION PROGRAMS

PARTICIPANTS’ ASSOCIATION (VPPPA)

The VPPPA is a private organization made up ofVPP participant companies. The VPPPA has mem-bers in most states where the Federal OSHA pro-gram operates and in many states where stateplans are in force. The VPPPA is willing to provideinformation, outreach, and mentoring to help work-sites improve their safety and health programs.Chapters of the national association have beenformed in most OSHA regions. Members of thesechapters also are willing to provide the kind ofassistance provided by the national organization.To contact your regional chapter of the VPPPA, callor write the OSHA Regional Office listed in the backof this publication for the address and telephonenumber of the chapter in your region. To contactthe VPPPA national organization, please call (703)761-1146 or write to the following address:

Voluntary Protection Programs Participants’Association7600 East Leesburg Pike, Suite 440Falls Church, VA 22043(703) 761-1146

SMALL BUSINESS DEVELOPMENT CENTERS

The U.S. Small Business Administration (SBA)administers the Small Business DevelopmentCenter Program to provide management and tech-nical assistance to current and prospective smallbusiness owners. There is a Small BusinessDevelopment Center (SBDC) in every state, theDistrict of Columbia, Puerto Rico, Guam, Samoa,and the U.S. Virgin Islands, with more than 1,000service centers across the country. SBDC assis-tance is tailored to the local community and the

Employer Rights and Responsibilities Following

an OSHA Inspection – OSHA 3000 (Spanish version 3195)

Hand and Power Tools – OSHA 3080

How to Plan for Workplace Emergencies and

Evacuations – OSHA 3088

It’s the Law Poster – OSHA 3165 (Spanish version 3167)

Job Hazard Analysis – OSHA 3071

Model Plans & Programs for the OSHA Bloodborne

Pathogens and Hazard Communications Standard

– OSHA 3186

Occupational Safety and Health Act – OSHA 2001

OSHA Inspections – OSHA 2098

Personal Protective Equipment – OSHA 3151

Servicing Single-Piece and Multi-Piece Rim Wheels –OSHA 3086

The following publications are available fromthe U.S. Government Printing Office (GPO),Superintendent of Documents, Washington, DC20402, phone toll-free (866) 512-1800, fax (202) 512-2250. Include GPO Order Number and makechecks payable to Superintendent of Documents.All prices are subject to change by GPO.

Hazard Communication: A Compliance Kit – OSHA3111Order No. 029-016-00200-6. Cost: $21.00

Construction Industry Digest – OSHA 2202Order No. 029-016-00212-0. Cost: $8.00

Materials Handling and Storing – OSHA 2236Order No. 029-016-00215-4. Cost: $3.75

Internet—There is an enormous amount of compli-ance assistance information on OSHA’s websitethat can be useful to the small business owner,found at http://www.osha.gov/dcsp/compliance_assistance/index.html. OSHA standards, interpreta-tions, directives and additional information are also available at http://www.osha.gov/ andhttp://www.osha-slc.gov/.

CD-ROM—A wide variety of OSHA materials,including standards, interpretations, directives, andmore, can be purchased on CD-ROM from the U.S.

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needs of individual clients and designed to deliverup-to-date counseling, training, and technical assis-tance. Services could include helping small busi-nesses with financial, marketing, production,organization, engineering, and technical problems.

NATIONAL INSTITUTE FOR OCCUPATIONAL

SAFETY AND HEALTH (NIOSH)

NIOSH is a research agency in the U.S.Department of Health and Human Services. (OSHAis a regulatory agency in the U.S. Department ofLabor). NIOSH conducts research and makes rec-ommendations to prevent work-related illness andinjury. NIOSH has produced a useful guide, Safetyand Health Resource Guide for Small Businesses,with telephone numbers, e-mail and Internet ad-dresses, and mailing information to enable smallbusinesses to contact government agencies, pri-vate organizations, consultants, and others whocan help with occupational safety and health is-sues. The NIOSH toll-free phone number is (800)356-4674, and its website address is www.cdc.gov/niosh.

WORKERS’ COMPENSATION CARRIERS AND

OTHER INSURANCE COMPANIES

Many workers’ compensation carriers, as wellas many liability and fire insurance companies,conduct periodic inspections and visits to evaluatesafety and health hazards. Managers of small andmedium-sized businesses need to know what serv-ices are available from these sources. Contact yourcarrier and see what it has to offer.

TRADE ASSOCIATIONS AND EMPLOYER GROUPS

Because of the increase in job safety and healthawareness resulting from OSHA activities, manytrade associations and employer groups have put anew emphasis on safety and health matters to bet-ter serve their members. If you are a member ofsuch a group, find out how it is assisting its mem-bers. If you are not a member, find out if thesegroups are circulating their materials to nonmem-bers, as many do.

TRADE UNIONS AND EMPLOYEE GROUPS

If your employees are organized, set up somecommunications, as you do in normal labor rela-tions, to get coordinated action on hazards in yourbusiness. Safety and health is one area where

advance planning will produce action on commongoals. Many trade unions have safety and healthexpertise that they are willing to share.

THE NATIONAL SAFETY COUNCIL AND

LOCAL CHAPTERS

The National Safety Council (NSC) has a broadrange of information services available. If youhave a local chapter of the NSC in your area, youcan call or visit to see how you can use materialspertaining to your business. If there is no chapternearby, you can write to:

National Safety Council1121 Spring Lake DriveItasca, IL 60143-3201

PROFESSIONAL ASSOCIATIONS

The following professional associations are anadditional resource that may be able to provideassistance to you:

American Society of Safety Engineers1800 East Oakton StreetDes Plaines, IL 60018-2187

American Industrial Hygiene Association2700 Prosperity AvenueSuite 250Fairfax, VA 22031-4319

American Conference of Governmental Industrial Hygienists1330 Kemper Meadow DriveCincinnati, OH 45240

SPECIFIC MEDICAL CONSULTATION

Talk to your local doctors or clinics for advice onworkplace medical matters on a consulting basis.Contact your local Red Cross chapter for assistancein first aid training. If you cannot identify a localchapter, call (800) 667-2968 or write to:

American National Red CrossNational HeadquartersSafety Programs2025 E Street, NWWashington, DC 20006

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Interest rate information on SBA loans may beobtained from any SBA office. They fluctuate butare generally lower than you can obtain elsewhere.You may wish to consult your own bank. It pays toshop around for loans.

Don’t forget to check with your accountant atincome tax time, since safety and health improve-ments can often be expensed or depreciated.

ADDITIONAL WEB PAGES OF INTEREST

TO SMALL BUSINESSES

(Internet websites change frequently; these list-ings may not be current.)

http://www.firstgov.govA website for all agencies of the Federal govern-ment.

http://www.sba.govThe U.S. Small Business Administration’s homepage.

http://www.businesslaw.govLegal and regulatory information for small busi-nesses by state.

http://www.regulations.govA site to enable small business owners to find allFederal regulations that are open for comment, toread them and to submit their views.

http://www.assistancecenters.net/For help with understanding environmental regula-tions that relate to the operation of your business.

http://www.irs.gov/businesses/small/index.htmlThis Internal Revenue Service website offers indus-try- and profession-specific tax information andguidelines.

YOUR LOCAL LIBRARY

Many local or university libraries contain infor-mation on specific safety and health subjects per-taining to your business. These materials are usu-ally in reference rooms or technical subject areas.Ask your librarian what is available. The librarymay be able to obtain materials for you throughinter-library loan, purchase, etc.

Two basic publications of the National SafetyCouncil will give you many sources of technicalinformation. The Accident Prevention Manual forIndustrial Operations is a basic reference book for all safety and health work. The second book,Fundamentals of Industrial Hygiene, contains excel-lent information on toxic materials and recom-mended health and hygiene practices. Both ofthese references list other sources at the end ofeach chapter that may help you in solving specificproblems.

FINANCING WORKPLACE IMPROVEMENT

The SBA is authorized to make loans to assistsmall businesses with meeting OSHA standards.Because SBA’s definition of a “small” businessvaries from industry to industry, contact your localSBA field office to determine whether you qualify.

A helpful hint: if you decide to apply for an SBAloan, experience indicates that most delays in pro-cessing SBA/OSHA loans are because applications(1) do not adequately describe each workplace con-dition to be corrected and identify one or moreOSHA standards applicable to the condition to becorrected, or (2) do not provide a reasonable esti-mate of the cost to correct each condition.

In most cases, safety hazards can be correctedwithout financial assistance. Health hazards maybe more costly to correct. The age and condition ofthe building and equipment are major factors to beconsidered.

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Major Action Steps to be Taken

1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

Priority Projected Actual(Assign each Completion CompletionStep a Number) Date Date

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Appendix A: Overall Action Plan Worksheet

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Specific Steps Required

1.

2.

3.

4.

5.

Persons Projected Problems/ ActualAssigned Completion Delays Completion

Date Encountered Date

Description of Action to be Taken:

Action Steps

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The following statements provide examples thatcan be used or modified by employers to help pre-vent employee injury and illness.

“The Occupational Safety and Health Act of 1970clearly states our common goal of safe and health-ful working conditions. The safety and health ofour employees continues to be the first considera-tion in the operation of this business.”

“Safety and health in our business must be a partof every operation. Without question it is everyemployee’s responsibility at all levels.”

“It is the intent of this company to comply with alllaws. To do this we must constantly be aware ofconditions in all work areas that can produce in-juries. No employee is required to work at a job heor she knows is not safe or healthful. Your cooper-ation in detecting hazards and, in turn, controllingthem is a condition of your employment. Informyour supervisor immediately of any situationbeyond your ability or authority to correct.”

“The personal safety and health of each employeeof this company is of primary importance. The pre-vention of occupationally-induced injuries and ill-nesses is of such consequence that it will be givenprecedence over operating productivity whenevernecessary. To the greatest degree possible, man-agement will provide all mechanical and physicalfacilities required for personal safety and health inkeeping with the highest standards.”

“We will maintain a safety and health program con-forming to the best practices of organizations ofthis type. To be successful, such a program mustembody the proper attitudes toward injury and ill-ness prevention on the part of supervisors andemployees. It also requires cooperation in all safe-ty and health matters, not only between supervisorand employee, but also between each employeeand his or her co-workers. Only through such acooperative effort can a safety program in the bestinterest of all be established and preserved.”

“Our objective is a safety and health program thatwill reduce the number of injuries and illnesses toan absolute minimum, not merely in keeping with,but surpassing, the best experience of operationssimilar to ours. Our goal is zero accidents and in-juries.”

“Our safety and health program will include:

■ Providing mechanical and physical safeguardsto the maximum extent possible.

■ A program of safety and health inspections toidentify and eliminate unsafe working condi-tions or practices, to control health hazards,and to comply fully with the safety and healthstandards for every job.

■ Training all employees in good safety andhealth practices.

■ Providing necessary personal protectiveequipment and instructions for its use andcare.

■ Developing and enforcing safety and healthrules and requiring that employees cooperatewith these rules as a condition of employ-ment.

■ Investigating, promptly and thoroughly, everyaccident to find out what caused it and to cor-rect the problem so that it won’t happen again.

■ Setting up a system of recognition and awardsfor outstanding safety service or performance.”

“We recognize that the responsibilities for safetyand health are shared:

■ The employer accepts responsibility for lead-ership of the safety and health program, forits effectiveness and improvement, and forproviding safe conditions.

■ Supervisors are responsible for developingthe proper attitudes toward safety and healthin themselves and in those they supervise,and for ensuring that all operations are per-formed with the utmost regard for the safetyand health of all personnel involved, includingthemselves.

■ Employees are responsible for compliancewith all rules and regulations and for continu-ously practicing safety while performing theirduties.”

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Appendix B: Model Policy Statements

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lines in a manner not within the scope of theirduties, unless they have received instructions fromtheir supervisor/employer.

10. All injuries shall be reported promptly to thesupervisor/employer so that arrangements can bemade for medical and/or first aid treatment. Firstaid materials are located in ____________; emer-gency, fire, ambulance, rescue squad, and doctors’telephone numbers are located ___________; andfire extinguishers are located at ___________.

Suggested Safety Rules

■ Do not throw material, tools, or other objectsfrom heights (whether structures or buildings)until proper precautions are taken to protectothers from the falling object hazard.

■ Wash thoroughly after handling injurious orpoisonous substances.

■ Gasoline shall not be used for cleaning purposes.

■ When using a ladder, always face the stepsand use both hands while climbing.

Use of Tools and Equipment

■ Keep faces of hammers in good condition toavoid flying nails and bruised fingers.

■ Files shall be equipped with handles; neveruse a file as a punch or pry.

■ Do not use a screwdriver as a chisel.

■ Do not lift or lower portable electric tools bythe power cords; use a rope.

■ Do not leave the cords of tools where cars ortrucks will run over them.

Machinery and Vehicles

■ Do not attempt to operate machinery or equip-ment without special permission unless it ispart of your regular duties.

■ Loose or frayed clothing, dangling ties, fingerrings, etc., must not be worn around movingmachinery or other places where they can getcaught.

■ Machinery shall not be repaired or adjustedwhile in operation.

This is a suggested code. It is general in natureand includes many types of small business activi-ties. It is intended only as a model that you cancustomize to describe your own work environment.

General Policy

1. All employees of this firm shall follow these safepractice rules, render every possible aid to safeoperations, and report all unsafe conditions orpractices to the supervisor/employer.

2. Supervisors shall insist that employees observeand obey every rule, regulation, and order neces-sary to the safe conduct of the work and take suchaction necessary to obtain compliance.

3. All employees shall be given frequent accidentprevention instructions. Instructions, practice drills,and articles concerning workplace safety andhealth shall be given at least once every _____working days.

4. Anyone known to be under the influence of alco-hol and/or drugs shall not be allowed on the jobwhile in that condition. Persons with symptoms ofalcohol and/or drug abuse are encouraged to dis-cuss personal or work-related problems with thesupervisor/employer.

5. No one shall knowingly be permitted or requiredto work while his or her ability or alertness is im-paired by fatigue, illness, or other causes thatmight expose the individual or others to injury.

6. Employees should be alert to see that all guardsand other protective devices are in proper placesand adjusted, and they shall report deficiencies.Approved protective equipment shall be worn inspecified work areas.

7. Horseplay, scuffling, and other acts that tend toendanger the safety or well-being of employees areprohibited.

8. Work shall be well planned and supervised toprevent injuries when working with equipment andhandling heavy materials. When lifting heavyobjects, employees should bend their knees anduse the large muscles of the legs instead of thesmaller muscles of the back. Back injuries are themost frequent and often the most persistent andpainful type of workplace injury.

9. Workers shall not handle or tamper with anyelectrical equipment, machinery, or air or water

Appendix C: Codes of Safe Practices

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OSHA has four separate sets of standards: GeneralIndustry (29 Code of Federal Regulations [CFR]1910), Construction (29 CFR 1926), MaritimeEmployment (29 CFR 1915-1919), and Agriculture(29 CFR 1928). OSHA has regulations on postingand other administrative matters in 29 CFR 1903and on recording and reporting of injuries and ill-nesses in 29 CFR 1904.

The OSH Act also has a general duty clause, sec-tion 5(a)(1), 29 U.S.C. 654(b)(1), which providesthat:

(a) Each employer – –

(1) shall furnish to each of his employees employ-ment and a place of employment which are freefrom recognized hazards that are causing or arelikely to cause death or serious physical harm tohis employees.

A recognized hazard is a danger recognized by theemployer’s industry or industry in general, by theemployer, or by common sense. The general dutyclause does not apply if there is an OSHA standarddealing with the hazard, unless the employer

knows that the standard does not adequatelyaddress the hazard.

General Industry, Maritime, and ConstructionOSHA standards are available at www.osha.gov.

After you have obtained a copy of the current stan-dards, identify those that apply to your business bya process of elimination. Read the introduction tothe subpart heading, and then analyze the possiblehazards in terms of your workplace, your equip-ment, your materials and of your employees. Forexample, if you are engaged in retail trade or serv-ice and you do not have compressed gases, flam-mables, or explosives on your premises, you caneliminate Hazardous Materials (Subpart H) as notapplying to your business.

If you have any questions in determining whether astandard is applicable to your workplace, you maycontact the nearest OSHA Area Office for assis-tance. Staff there should be able to answer anyquestions you may have about standards and pro-vide general guidelines on methods of implemen-tation in your workplace. Small businesses areencouraged to participate in the development ofstandards.

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Appendix D: OSHA Job Safety and Health Standards,Regulations and Requirements

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In 1996, Congress passed the Small BusinessRegulatory Enforcement Fairness Act, or SBREFA,in response to concerns expressed by the smallbusiness community that Federal regulations weretoo numerous, too complex and too expensive toimplement. SBREFA was designed to give smallbusinesses assistance in understanding and com-plying with regulations and more of a voice in thedevelopment of new regulations. Under SBREFA,the Occupational Safety and Health Administration(OSHA) and other Federal agencies must:

■ Produce Small Entity Compliance Guides forsome rules;

■ Be responsive to small business inquiriesabout compliance with the agency’s regula-tions;

■ Submit final rules to Congress for review;

■ Have a penalty reduction policy for small busi-nesses; and

■ Involve small businesses in the developmentof some proposed rules through SmallBusiness Advocacy Review Panels.

Commenting on Enforcement Actions

Under a law passed by Congress in 1996, the SmallBusiness Administration (SBA) has established anSBA Ombudsman and SBA Regional FairnessBoards to investigate small business complaintsabout Federal agency enforcement actions.If you are a small business and believe that youhave been treated unfairly by OSHA, you may file

an electronic comment/complaint with the SBAOmbudsman over the Internet at:http://www.sba.gov/ombudsman/comments/com-mentform1.htmlOr you may contact the SBA's Office of theNational Ombudsman by:

■ Toll Free Phone: (888) REG-FAIR (734-3247)

■ Fax: (202) 481-5719

■ E-mail: [email protected]

■ Mail: Office of the National Ombudsman U.S. Small Business Administration 409 3rd Street, S.W., MC2120 Washington, DC 20416-0005

To view the SBREFA Act in its entirety, please visit the following web link: http://www.sba.gov/advo/laws/sbrefa.html

For more information on SBREFA the followingweb links may prove helpful: http://www.sba.gov/ombudsman/http://www.sba.gov/ombudsman/dsp_overview.htmlhttp://www.sba.gov/ombudsman/dsp_faq.html http://www.sba.gov/advo/ http://www.sba.gov/advo/laws/is_oshapanel.html

NOTE: Filing a complaint with the SBAOmbudsman does not affect any obligation thatyou may have to comply with an OSHA citation orother enforcement action. Nor does it mean thatyou need not take other available legal steps toprotect your interests.

Appendix E: Small Business Regulatory Enforcement Fairness Act of 1996 (SBREFA)

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Region VIII

(CO, MT, ND, SD, UT,* WY*) 1999 Broadway, Suite 1690 PO Box 46550 Denver, CO 80201-6550 (303) 844–1600

Region IX

(American Samoa, AZ,* CA,* HI,* NV,* Northern Mariana Islands) 71 Stevenson Street, Room 420 San Francisco, CA 94105 (415) 975–4310

Region X

(AK,* ID, OR,* WA*) 1111 Third Avenue, Suite 715 Seattle, WA 98101-3212 (206) 553–5930

*These states and territories operate their ownOSHA-approved job safety and health programs(Connecticut, New Jersey, New York and PuertoRico plans cover public employees only). Stateswith approved programs must have a standard thatis identical to, or at least as effective as, the Federalstandard. Note: To get contact information for OSHA AreaOffices, OSHA-approved State Plans, and OSHAConsultation Projects, please visit us online atwww.osha.gov or call us at (800) 321-OSHA (6742).

Contact Information

The most complete and current information and e-mail addresses for OSHA Regional and Area Officesand the state Consultation Projects can be foundon OSHA’s website at www.osha.gov/html/oshdir.html or by contacting:

U.S. Department of LaborOccupational Safety and Health Administration Directorate of Cooperative and State ProgramsOffice of Small Business Assistance200 Constitution Ave., NWWashington, DC 20210(800) 321-OSHA

OSHA Regional Offices

Region I

(CT,* ME, MA, NH, RI, VT*) JFK Federal Building, Room E340 Boston, MA 02203 (617) 565–9860

Region II

(NJ,* NY,* PR,* VI*) 201 Varick Street, Room 670 New York, NY 10014 (212) 337–2378

Region III

(DE, DC, MD,* PA, VA,* WV) The Curtis Center 170 S. Independence Mall West Suite 740 West Philadelphia, PA 19106-3309 (215) 861–4900

Region IV

(AL, FL, GA, KY,* MS, NC,* SC,* TN*) SNAF 61 Forsyth Street SW, Room 6T50 Atlanta, GA 30303 (404) 562–2300

Region V

(IL, IN,* MI,* MN,* OH, WI) 230 South Dearborn Street, Room 3244 Chicago, IL 60604 (312) 353–2220

Region VI

(AR, LA, NM,* OK, TX) 525 Griffin Street, Room 602 Dallas, TX 75202 (214) 767–4731 or 4736 x224

Region VII

(IA,* KS, MO, NE) City Center Square 1100 Main Street, Suite 800 Kansas City, MO 64105 (816) 426–5861

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OSHA’s Non-Retaliation Policy

The Occupational Safety and Health Administration(OSHA) has a long-established policy that informa-tion inquiries received by the agency regardingsafety and health regulations or other safety-relatedsubjects shall not trigger an inspection. This policyis outlined in OSHA Instruction CPL 02-00-103 (CPL2.103), Field Inspection Reference Manual, Section5 - Chapter I, B.4.b. The exact wording is:

Employer Contacts. Contacts for information initiat-ed by employers or their representatives shall nottrigger an inspection, nor shall such employerinquiries protect them against regular inspectionsconducted pursuant to guidelines established bythe agency. Further, if an employer or its represen-tatives indicates that an imminent danger exists orthat a fatality or catastrophe has occurred, the AreaDirector shall act in accordance with establishedinspection priority procedures.

While exceptions to this policy exist, such as thepresence of an imminent danger or the occurrenceof a fatality, OSHA policy is to provide assistance tohelp employers prevent and reduce workplacefatalities, illnesses and injuries.

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www.osha.gov

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Personal ProtectiveEquipment

OSHA 3151-12R 2003

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This informational booklet provides a general overview of a particular topic related to OSHA standards. It does not alteror determine compliance responsibilities inOSHA standards or the Occupational Safetyand Health Act of 1970. Because interpreta-tions and enforcement policy may changeover time, you should consult current OSHAadministrative interpretations and decisionsby the Occupational Safety and HealthReview Commission and the Courts for additional guidance on OSHA compliancerequirements.

This publication is in the public domain and may be reproduced, fully or partially,without permission. Source credit is requested but not required.

This information is available to sensoryimpaired individuals upon request.Voice phone: (202) 693-1999; teletypewriter(TTY) number: (877) 889-5627.

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OSHA 3151-12R2003

Personal ProtectiveEquipment

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ContentsIntroduction...4

The Requirement for PPE...5

The Hazard Assessment...6

Selecting PPE...8

Training Employees in the Proper Use of PPE...9

Eye and Face Protection...9

Prescription Lenses...10

Eye Protection for Exposed Workers...10

Types of Eye Protection...11

Welding Operations...12

Laser Operations...16

Head Protection...16

Types of Hard Hats...18

Size and Care Considerations...18

Foot and Leg Protection...19

Special Purpose Shoes...21

Foundry Shoes...22

Care of Protective Footwear...22

Hand and Arm Protection...22

Types of Protective Gloves...23

Leather, Canvas or Metal Mesh Gloves...23

Fabric and Coated Fabric Gloves...24

Chemical- and Liquid-Resistant Gloves...24

Care of Protective Gloves...29

Body Protection...29

Hearing Protection...30

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OSHA Assistance...32

Safety and Health Program Management Guidelines...33

State Programs...33

Consultation Services...34

Voluntary Protection Programs (VPP)...34

Strategic Partnership Program...35

Alliance Programs...35

OSHA Training and Education...36

Information Available Electronically...36

OSHA Publications...37

Contacting OSHA...37

OSHA Regional Offices...38

List of TablesTable 1:

Filter Lenses for Protection Against Radiant Energy...13

Table 2:

Construction Industry Requirements for Filter Lens Shade

Numbers for Protection Against Radiant Energy...15

Table 3:

Selecting Laser Safety Glass...16

Table 4:

Chemical Resistance Selection Chart for Protective

Gloves...26

Table 5:

Permissible Noise Exposures...31

Appendix A: OSHA Standards that Require PPE...40

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Introduction

Hazards exist in every workplace in many different forms: sharpedges, falling objects, flying sparks, chemicals, noise and a myriadof other potentially dangerous situations. The Occupational Safetyand Health Administration (OSHA) requires that employers protecttheir employees from workplace hazards that can cause injury.

Controlling a hazard at its source is the best way to protectemployees. Depending on the hazard or workplace conditions,OSHA recommends the use of engineering or work practicecontrols to manage or eliminate hazards to the greatest extentpossible. For example, building a barrier between the hazard andthe employees is an engineering control; changing the way in whichemployees perform their work is a work practice control.

When engineering, work practice and administrative controls arenot feasible or do not provide sufficient protection, employers mustprovide personal protective equipment (PPE) to their employeesand ensure its use. Personal protective equipment, commonlyreferred to as "PPE", is equipment worn to minimize exposure to avariety of hazards. Examples of PPE include such items as gloves,foot and eye protection, protective hearing devices (earplugs,muffs) hard hats, respirators and full body suits.

This guide will help both employers and employees do thefollowing:� Understand the types of PPE. � Know the basics of conducting a "hazard assessment" of the

workplace.� Select appropriate PPE for a variety of circumstances.� Understand what kind of training is needed in the proper use

and care of PPE.

The information in this guide is general in nature and does notaddress all workplace hazards or PPE requirements. Theinformation, methods and procedures in this guide are based onthe OSHA requirements for PPE as set forth in the Code of FederalRegulations (CFR) at 29 CFR 1910.132 (General requirements); 29CFR 1910.133 (Eye and face protection); 29 CFR 1910.135 (Headprotection); 29 CFR 1910.136 (Foot protection); 29 CFR 1910. 137(Electrical protective equipment); 29 CFR 1910.138 (Handprotection); and regulations that cover the construction industry, at

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29 CFR 1926.95 (Criteria for personal protective equipment); 29 CFR1926.96 (Occupational foot protection); 29 CFR 1926.100 (Headprotection); 29 CFR 1926.101 (Hearing protection); and 29 CFR1926.102 (Eye and face protection); and for the maritime industry at29 CFR 1915.152 (General requirements); 29 CFR 1915.153 (Eye andface protection); 29 CFR 1915.155 (Head protection); 29 CFR1915.156 (Foot protection); and 29 CFR 1915.157 (Hand and bodyprotection).

This guide does not address PPE requirements related torespiratory protection (29 CFR 1910.134) as this information iscovered in detail in OSHA Publication 3079, "RespiratoryProtection". There is a brief discussion of hearing protection in thispublication but users should refer to OSHA Publication 3074,"Hearing Conservation" for more detailed information on therequirements to protect employees’ hearing in the workplace.

The Requirement for PPE

To ensure the greatest possible protection for employees in theworkplace, the cooperative efforts of both employers andemployees will help in establishing and maintaining a safe andhealthful work environment.

In general, employers are responsible for:� Performing a "hazard assessment" of the workplace to identify

and control physical and health hazards.� Identifying and providing appropriate PPE for employees.� Training employees in the use and care of the PPE.� Maintaining PPE, including replacing worn or damaged PPE.� Periodically reviewing, updating and evaluating the effectiveness

of the PPE program.

In general, employees should:� Properly wear PPE, � Attend training sessions on PPE,� Care for, clean and maintain PPE, and� Inform a supervisor of the need to repair or replace PPE.

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Specific requirements for PPE are presented in many differentOSHA standards, published in 29 CFR. Some standards require thatemployers provide PPE at no cost to the employee while otherssimply state that the employer must provide PPE. Appendix A atpage 40 lists those standards that require the employer to providePPE and those that require the employer to provide PPE at no costto the employee.

The Hazard Assessment

A first critical step in developing a comprehensive safety andhealth program is to identify physical and health hazards in theworkplace. This process is known as a "hazard assessment."Potential hazards may be physical or health-related and a compre-hensive hazard assessment should identify hazards in bothcategories. Examples of physical hazards include moving objects,fluctuating temperatures, high intensity lighting, rolling or pinchingobjects, electrical connections and sharp edges. Examples of healthhazards include overexposure to harmful dusts, chemicals orradiation.

The hazard assessment should begin with a walk-throughsurvey of the facility to develop a list of potential hazards in thefollowing basic hazard categories:� Impact,� Penetration,� Compression (roll-over),� Chemical,� Heat/cold,� Harmful dust,� Light (optical) radiation, and� Biologic.

In addition to noting the basic layout of the facility andreviewing any history of occupational illnesses or injuries, things to look for during the walk-through survey include:� Sources of electricity.� Sources of motion such as machines or processes where

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movement may exist that could result in an impact betweenpersonnel and equipment.

� Sources of high temperatures that could result in burns, eyeinjuries or fire.

� Types of chemicals used in the workplace.� Sources of harmful dusts.� Sources of light radiation, such as welding, brazing, cutting,

furnaces, heat treating, high intensity lights, etc.� The potential for falling or dropping objects.� Sharp objects that could poke, cut, stab or puncture.� Biologic hazards such as blood or other potentially infected

material.

When the walk-through is complete, the employer shouldorganize and analyze the data so that it may be efficiently used indetermining the proper types of PPE required at the worksite. Theemployer should become aware of the different types of PPEavailable and the levels of protection offered. It is definitely a goodidea to select PPE that will provide a level of protection greater thanthe minimum required to protect employees from hazards.

The workplace should be periodically reassessed for anychanges in conditions, equipment or operating procedures thatcould affect occupational hazards. This periodic reassessmentshould also include a review of injury and illness records to spotany trends or areas of concern and taking appropriate correctiveaction. The suitability of existing PPE, including an evaluation of itscondition and age, should be included in the reassessment.

Documentation of the hazard assessment is required through awritten certification that includes the following information:� Identification of the workplace evaluated;� Name of the person conducting the assessment;� Date of the assessment; and� Identification of the document certifying completion of the

hazard assessment.

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Selecting PPE

All PPE clothing and equipment should be of safe design andconstruction, and should be maintained in a clean and reliablefashion. Employers should take the fit and comfort of PPE into con-sideration when selecting appropriate items for their workplace.PPE that fits well and is comfortable to wear will encourageemployee use of PPE. Most protective devices are available inmultiple sizes and care should be taken to select the proper size foreach employee. If several different types of PPE are worn together,make sure they are compatible. If PPE does not fit properly, it canmake the difference between being safely covered or dangerouslyexposed. It may not provide the level of protection desired and maydiscourage employee use.

OSHA requires that many categories of PPE meet or be equivalentto standards developed by the American National Standards Institute(ANSI). ANSI has been preparing safety standards since the 1920s,when the first safety standard was approved to protect the heads andeyes of industrial workers. Employers who need to provide PPE inthe categories listed below must make certain that any newequipment procured meets the cited ANSI standard. Existing PPEstocks must meet the ANSI standard in effect at the time of itsmanufacture or provide protection equivalent to PPE manufacturedto the ANSI criteria. Employers should inform employees whoprovide their own PPE of the employer’s selection decisions andensure that any employee-owned PPE used in the workplaceconforms to the employer’s criteria, based on the hazard assessment,OSHA requirements and ANSI standards. OSHA requires PPE tomeet the following ANSI standards:� Eye and Face Protection: ANSI Z87.1-1989 (USA Standard for

Occupational and Educational Eye and Face Protection).� Head Protection: ANSI Z89.1-1986.� Foot Protection: ANSI Z41.1-1991.

For hand protection, there is no ANSI standard for gloves butOSHA recommends that selection be based upon the tasks to beperformed and the performance and construction characteristics ofthe glove material. For protection against chemicals, glove selection

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must be based on the chemicals encountered, the chemicalresistance and the physical properties of the glove material.

Training Employees in the Proper Use of PPE

Employers are required to train each employee who must usePPE. Employees must be trained to know at least the following:� When PPE is necessary.� What PPE is necessary.� How to properly put on, take off, adjust and wear the PPE.� The limitations of the PPE.� Proper care, maintenance, useful life and disposal of PPE.

Employers should make sure that each employee demonstratesan understanding of the PPE training as well as the ability toproperly wear and use PPE before they are allowed to performwork requiring the use of the PPE. If an employer believes that apreviously trained employee is not demonstrating the properunderstanding and skill level in the use of PPE, that employeeshould receive retraining. Other situations that require additional orretraining of employees include the following circumstances:changes in the workplace or in the type of required PPE that makeprior training obsolete.

The employer must document the training of each employeerequired to wear or use PPE by preparing a certification containingthe name of each employee trained, the date of training and a clearidentification of the subject of the certification.

Eye and Face Protection

Employees can be exposed to a large number of hazards thatpose danger to their eyes and face. OSHA requires employers toensure that employees have appropriate eye or face protection ifthey are exposed to eye or face hazards from flying particles,molten metal, liquid chemicals, acids or caustic liquids, chemicalgases or vapors, potentially infected material or potentially harmfullight radiation.

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Many occupational eye injuries occur because workers are notwearing any eye protection while others result from wearingimproper or poorly fitting eye protection. Employers must be surethat their employees wear appropriate eye and face protection andthat the selected form of protection is appropriate to the work beingperformed and properly fits each worker exposed to the hazard.

Prescription LensesEveryday use of prescription corrective lenses will not provide

adequate protection against most occupational eye and facehazards, so employers must make sure that employees withcorrective lenses either wear eye protection that incorporates theprescription into the design or wear additional eye protection overtheir prescription lenses. It is important to ensure that the protectiveeyewear does not disturb the proper positioning of the prescriptionlenses so that the employee’s vision will not be inhibited or limited.Also, employees who wear contact lenses must wear eye or facePPE when working in hazardous conditions.

Eye Protection for Exposed WorkersOSHA suggests that eye protection be routinely considered for use by

carpenters, electricians, machinists, mechanics, millwrights, plumbers andpipefitters, sheetmetal workers and tinsmiths, assemblers, sanders,grinding machine operators, sawyers, welders, laborers, chemical pro-cess operators and handlers, and timber cutting and logging workers.Employers of workers in other job categories should decide whetherthere is a need for eye and face PPE through a hazard assessment.

Examples of potential eye or face injuries include:� Dust, dirt, metal or wood chips entering the eye from activities

such as chipping, grinding, sawing, hammering, the use ofpower tools or even strong wind forces.

� Chemical splashes from corrosive substances, hot liquids,solvents or other hazardous solutions.

� Objects swinging into the eye or face, such as tree limbs, chains,tools or ropes.

� Radiant energy from welding, harmful rays from the use oflasers or other radiant light (as well as heat, glare, sparks, splashand flying particles).

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Types of Eye ProtectionSelecting the most suitable eye and face protection for

employees should take into consideration the following elements:� Ability to protect against specific workplace hazards.� Should fit properly and be reasonably comfortable to wear.� Should provide unrestricted vision and movement.� Should be durable and cleanable.� Should allow unrestricted functioning of any other required PPE.

The eye and face protection selected for employee use mustclearly identify the manufacturer. Any new eye and face protectivedevices must comply with ANSI Z87.1-1989 or be at least as effectiveas this standard requires. Any equipment purchased before thisrequirement took effect on July 5, 1994, must comply with theearlier ANSI Standard (ANSI Z87.1-1968) or be shown to be equallyeffective.

An employer may choose to provide one pair of protectiveeyewear for each position rather than individual eyewear for eachemployee. If this is done, the employer must make sure thatemployees disinfect shared protective eyewear after each use.Protective eyewear with corrective lenses may only be used by theemployee for whom the corrective prescription was issued and maynot be shared among employees.

Some of the most common types of eye and face protectioninclude the following:� Safety spectacles. These protective eyeglasses have safety

frames constructed of metal or plastic and impact-resistantlenses. Side shields are available on some models.

� Goggles. These are tight-fitting eye protection that completelycover the eyes, eye sockets and the facial area immediatelysurrounding the eyes and provide protection from impact, dustand splashes. Some goggles will fit over corrective lenses.

� Welding shields. Constructed of vulcanized fiber or fiberglassand fitted with a filtered lens, welding shields protect eyes fromburns caused by infrared or intense radiant light; they alsoprotect both the eyes and face from flying sparks, metal spatterand slag chips produced during welding, brazing, soldering and

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cutting operations. OSHA requires filter lenses to have a shadenumber appropriate to protect against the specific hazards of thework being performed in order to protect against harmful lightradiation.

� Laser safety goggles. These specialty goggles protect againstintense concentrations of light produced by lasers. The type oflaser safety goggles an employer chooses will depend upon theequipment and operating conditions in the workplace.

� Face shields. These transparent sheets of plastic extend fromthe eyebrows to below the chin and across the entire width ofthe employee’s head. Some are polarized for glare protection.Face shields protect against nuisance dusts and potentialsplashes or sprays of hazardous liquids but will not provideadequate protection against impact hazards. Face shields used in combination with goggles or safety spectacles will provideadditional protection against impact hazards.

Each type of protective eyewear is designed to protect againstspecific hazards. Employers can identify the specific workplacehazards that threaten employees’ eyes and faces by completing ahazard assessment as outlined in the earlier section.

Welding OperationsThe intense light associated with welding operations can cause

serious and sometimes permanent eye damage if operators do notwear proper eye protection. The intensity of light or radiant energyproduced by welding, cutting or brazing operations variesaccording to a number of factors including the task producing thelight, the electrode size and the arc current. The following tableshows the minimum protective shades for a variety of welding,cutting and brazing operations in general industry and in the shipbuilding industry.

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Table 1Filter Lenses for Protection Against Radiant Energy

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Operations Electrode size in Arc current Minimum*1/32” (0.8mm) protective

shade

Shielded metal arc welding < 3 < 60 7

3 - 5 60 - 160 85 - 8 160 - 250 10> 8 250 - 550 11

Gas metal arc welding and flux cored arc welding < 60 7

60 - 160 10160 - 250 10250 - 500 10

Gas tungsten arc welding < 50 8

50 - 150 8150 - 500 10

Air carbon (light) < 500 10

Arc cutting (heavy) 500 - 1,000 11

Plasma arc welding < 20 620 - 100 8

100 - 400 10400 - 800 11

Plasma arc cutting (light)** < 300 8(medium)** 300 - 400 9(heavy)** 400 - 800 10

Torch brazing 3

Torch soldering 2

Carbon arc welding 14

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Table 1 (continued)Filter Lenses for Protection Against Radiant Energy

Operations Plate thickness Plate thickness Minimum*inches mm protective

shade

Gas welding:Light < 1/8 < 3.2 4

Gas welding: Medium 1/8 - 1/2 3.2 - 12.7 5

Gas welding:Heavy > 1/2 > 12.7 6

Oxygen cutting:Light < 1 < 25 3

Oxygen cutting:Medium 1 - 6 25 - 150 4

Oxygen cutting: Heavy > 6 > 150 5

Source: 29 CFR 1910.133(a)(5).

* As a rule of thumb, start with a shade that is too dark to see the weldzone. Then go to a lighter shade which gives sufficient view of the weldzone without going below the minimum. In oxyfuel gas welding orcutting where the torch produces a high yellow light, it is desirable touse a filter lens that absorbs the yellow or sodium line in the visible lightof the (spectrum) operation.

** These values apply where the actual arc is clearly seen. Experiencehas shown that lighter filters may be used when the arc is hidden by theworkpiece.

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The construction industry has separate requirements for filterlens protective levels for specific types of welding operations, asindicated in the table below:

Table 2Construction Industry Requirements for Filter Lens Shade

Numbers for Protection Against Radiant Energy

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Welding Operation Shade Number

Shielded metal-arc welding1/16-, 3/32-, 1/8-, 5/32-inch diameter electrodes 10

Gas-shielded arc welding (nonferrous)1/16-, 3/32-, 1/8-, 5/32-inch diameter electrodes 11

Gas-shielded arc welding (ferrous)1/16-, 3/32-, 1/8-, 5/32-inch diameter electrodes 12

Shielded metal-arc welding3/16-, 7/32-, 1/4-inch diameter electrodes 12

5/16-, 3/8-inch diameter electrodes 14

Atomic hydrogen welding 10 - 14

Carbon-arc welding 14

Soldering 2

Torch brazing 3 or 4

Light cutting, up to 1 inch 3 or 4

Medium cutting, 1 to 6 inches 4 or 5

Heavy cutting, more than 6 inches 5 or 6

Gas welding (light), up to 1/8-inch 4 or 5

Gas welding (medium), 1/8- to 1/2-inch 5 or 6

Gas welding (heavy), more than 1/2-inch 6 or 8

Source: 29 CFR 1926.102(b)(1).

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Laser OperationsLaser light radiation can be extremely dangerous to the

unprotected eye and direct or reflected beams can causepermanent eye damage. Laser retinal burns can be painless, so it is essential that all personnel in or around laser operations wear appropriate eye protection.

Laser safety goggles should protect for the specific wavelengthof the laser and must be of sufficient optical density for the energyinvolved. Safety goggles intended for use with laser beams must belabeled with the laser wavelengths for which they are intended tobe used, the optical density of those wavelengths and the visiblelight transmission.

The table below lists maximum power or energy densities andappropriate protection levels for optical densities 5 through 8.

Table 3Selecting Laser Safety Glass

Intensity, CW maximum Attenuation

power density (watts/cm2) Optical density Attenuation

(O.D.) factor

10-2 5 105

10-1 6 106

1.0 7 107

10.0 8 108

Source: 29 CFR 1926.102(b)(2).

Head Protection

Protecting employees from potential head injuries is a keyelement of any safety program. A head injury can impair anemployee for life or it can be fatal. Wearing a safety helmet or hardhat is one of the easiest ways to protect an employee’s head from

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injury. Hard hats can protect employees from impact andpenetration hazards as well as from electrical shock and burnhazards.

Employers must ensure that their employees wear headprotection if any of the following apply:� Objects might fall from above and strike them on the head;� They might bump their heads against fixed objects, such as

exposed pipes or beams; or� There is a possibility of accidental head contact with electrical

hazards.

Some examples of occupations in which employees should berequired to wear head protection include construction workers,carpenters, electricians, linemen, plumbers and pipefitters, timberand log cutters, welders, among many others. Whenever there is adanger of objects falling from above, such as working below otherswho are using tools or working under a conveyor belt, headprotection must be worn. Hard hats must be worn with the billforward to protect employees properly.

In general, protective helmets or hard hats should do thefollowing:� Resist penetration by objects.� Absorb the shock of a blow.� Be water-resistant and slow burning.� Have clear instructions explaining proper adjustment and

replacement of the suspension and headband.

Hard hats must have a hard outer shell and a shock-absorbinglining that incorporates a headband and straps that suspend theshell from 1 to 1 1/4 inches (2.54 cm to 3.18 cm) away from thehead. This type of design provides shock absorption during animpact and ventilation during normal wear.

Protective headgear must meet ANSI Standard Z89.1-1986(Protective Headgear for Industrial Workers) or provide anequivalent level of protection. Helmets purchased before July 5,1994 must comply with the earlier ANSI Standard (Z89.1-1969) or provide equivalent protection.

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Types of Hard HatsThere are many types of hard hats available in the marketplace

today. In addition to selecting protective headgear that meets ANSIstandard requirements, employers should ensure that employeeswear hard hats that provide appropriate protection against potentialworkplace hazards. It is important for employers to understand allpotential hazards when making this selection, including electricalhazards. This can be done through a comprehensive hazardanalysis and an awareness of the different types of protectiveheadgear available.

Hard hats are divided into three industrial classes:� Class A hard hats provide impact and penetration resistance

along with limited voltage protection (up to 2,200 volts).� Class B hard hats provide the highest level of protection against

electrical hazards, with high-voltage shock and burn protection(up to 20,000 volts). They also provide protection from impactand penetration hazards by flying/falling objects.

� Class C hard hats provide lightweight comfort and impactprotection but offer no protection from electrical hazards.

Another class of protective headgear on the market is called a“bump hat,” designed for use in areas with low head clearance.They are recommended for areas where protection is needed fromhead bumps and lacerations. These are not designed to protectagainst falling or flying objects and are not ANSI approved. It isessential to check the type of hard hat employees are using toensure that the equipment provides appropriate protection. Eachhat should bear a label inside the shell that lists the manufacturer,the ANSI designation and the class of the hat.

Size and Care ConsiderationsHead protection that is either too large or too small is inappro-

priate for use, even if it meets all other requirements. Protectiveheadgear must fit appropriately on the body and for the head sizeof each individual. Most protective headgear comes in a variety ofsizes with adjustable headbands to ensure a proper fit (many adjustin 1/8-inch increments). A proper fit should allow sufficientclearance between the shell and the suspension system for

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ventilation and distribution of an impact. The hat should not bind,slip, fall off or irritate the skin.

Some protective headgear allows for the use of variousaccessories to help employees deal with changing environmentalconditions, such as slots for earmuffs, safety glasses, face shieldsand mounted lights. Optional brims may provide additionalprotection from the sun and some hats have channels that guiderainwater away from the face. Protective headgear accessories mustnot compromise the safety elements of the equipment.

Periodic cleaning and inspection will extend the useful life ofprotective headgear. A daily inspection of the hard hat shell,suspension system and other accessories for holes, cracks, tears orother damage that might compromise the protective value of thehat is essential. Paints, paint thinners and some cleaning agents canweaken the shells of hard hats and may eliminate electricalresistance. Consult the helmet manufacturer for information on theeffects of paint and cleaning materials on their hard hats. Never drillholes, paint or apply labels to protective headgear as this mayreduce the integrity of the protection. Do not store protectiveheadgear in direct sunlight, such as on the rear window shelf of acar, since sunlight and extreme heat can damage them.

Hard hats with any of the following defects should be removedfrom service and replaced:� Perforation, cracking, or deformity of the brim or shell;� Indication of exposure of the brim or shell to heat, chemicals or

ultraviolet light and other radiation (in addition to a loss ofsurface gloss, such signs include chalking or flaking).

Always replace a hard hat if it sustains an impact, even ifdamage is not noticeable. Suspension systems are offered asreplacement parts and should be replaced when damaged or whenexcessive wear is noticed. It is not necessary to replace the entirehard hat when deterioration or tears of the suspension systems arenoticed.

Foot and Leg Protection

Employees who face possible foot or leg injuries from falling orrolling objects or from crushing or penetrating materials should

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wear protective footwear. Also, employees whose work involvesexposure to hot substances or corrosive or poisonous materialsmust have protective gear to cover exposed body parts, includinglegs and feet. If an employee’s feet may be exposed to electricalhazards, non-conductive footwear should be worn. On the otherhand, workplace exposure to static electricity may necessitate theuse of conductive footwear.

Examples of situations in which an employee should wear footand/or leg protection include:� When heavy objects such as barrels or tools might roll onto or

fall on the employee’s feet;� Working with sharp objects such as nails or spikes that could

pierce the soles or uppers of ordinary shoes;� Exposure to molten metal that might splash on feet or legs;� Working on or around hot, wet or slippery surfaces; and� Working when electrical hazards are present.

Safety footwear must meet ANSI minimum compression andimpact performance standards in ANSI Z41-1991 (AmericanNational Standard for Personal Protection-Protective Footwear) orprovide equivalent protection. Footwear purchased before July 5,1994, must meet or provide equivalent protection to the earlierANSI Standard (ANSI Z41.1-1967). All ANSI approved footwear hasa protective toe and offers impact and compression protection. Butthe type and amount of protection is not always the same.Different footwear protects in different ways. Check the product’slabeling or consult the manufacturer to make sure the footwear willprotect the user from the hazards they face.

Foot and leg protection choices include the following:� Leggings protect the lower legs and feet from heat hazards such

as molten metal or welding sparks. Safety snaps allow leggingsto be removed quickly.

� Metatarsal guards protect the instep area from impact andcompression. Made of aluminum, steel, fiber or plastic, theseguards may be strapped to the outside of shoes.

� Toe guards fit over the toes of regular shoes to protect the toesfrom impact and compression hazards. They may be made ofsteel, aluminum or plastic.

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� Combination foot and shin guards protect the lower legs andfeet, and may be used in combination with toe guards whengreater protection is needed.

� Safety shoes have impact-resistant toes and heat-resistant solesthat protect the feet against hot work surfaces common inroofing, paving and hot metal industries. The metal insoles ofsome safety shoes protect against puncture wounds. Safetyshoes may also be designed to be electrically conductive toprevent the buildup of static electricity in areas with the potentialfor explosive atmospheres or nonconductive to protect workersfrom workplace electrical hazards.

Special Purpose ShoesElectrically conductive shoes provide protection against the

buildup of static electricity. Employees working in explosive andhazardous locations such as explosives manufacturing facilities orgrain elevators must wear conductive shoes to reduce the risk ofstatic electricity buildup on the body that could produce a spark andcause an explosion or fire. Foot powder should not be used inconjunction with protective conductive footwear because itprovides insulation, reducing the conductive ability of the shoes.Silk, wool and nylon socks can produce static electricity and shouldnot be worn with conductive footwear. Conductive shoes must beremoved when the task requiring their use is completed. Note:Employees exposed to electrical hazards must never wearconductive shoes.

Electrical hazard, safety-toe shoes are nonconductive and willprevent the wearers’ feet from completing an electrical circuit to theground. These shoes can protect against open circuits of up to 600volts in dry conditions and should be used in conjunction withother insulating equipment and additional precautions to reducethe risk of a worker becoming a path for hazardous electricalenergy. The insulating protection of electrical hazard, safety-toeshoes may be compromised if the shoes become wet, the soles areworn through, metal particles become embedded in the sole orheel, or workers touch conductive, grounded items. Note:Nonconductive footwear must not be used in explosive orhazardous locations.

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Foundry ShoesIn addition to insulating the feet from the extreme heat of

molten metal, foundry shoes keep hot metal from lodging in shoeeyelets, tongues or other shoe parts. These snug-fitting leather orleather-substitute shoes have leather or rubber soles and rubberheels. All foundry shoes must have built-in safety toes.

Care of Protective FootwearAs with all protective equipment, safety footwear should be

inspected prior to each use. Shoes and leggings should be checkedfor wear and tear at reasonable intervals. This includes looking forcracks or holes, separation of materials, broken buckles or laces.The soles of shoes should be checked for pieces of metal or otherembedded items that could present electrical or tripping hazards.Employees should follow the manufacturers’ recommendations forcleaning and maintenance of protective footwear.

Hand and Arm Protection

If a workplace hazard assessment reveals that employees facepotential injury to hands and arms that cannot be eliminatedthrough engineering and work practice controls, employers mustensure that employees wear appropriate protection. Potentialhazards include skin absorption of harmful substances, chemical or thermal burns, electrical dangers, bruises, abrasions, cuts,punctures, fractures and amputations. Protective equipmentincludes gloves, finger guards and arm coverings or elbow-lengthgloves.

Employers should explore all possible engineering and workpractice controls to eliminate hazards and use PPE to provideadditional protection against hazards that cannot be completelyeliminated through other means. For example, machine guardsmay eliminate a hazard. Installing a barrier to prevent workersfrom placing their hands at the point of contact between a tablesaw blade and the item being cut is another method.

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Types of Protective GlovesThere are many types of gloves available today to protect

against a wide variety of hazards. The nature of the hazard and theoperation involved will affect the selection of gloves. The variety ofpotential occupational hand injuries makes selecting the right pairof gloves challenging. It is essential that employees use glovesspecifically designed for the hazards and tasks found in theirworkplace because gloves designed for one function may notprotect against a different function even though they may appear tobe an appropriate protective device.

The following are examples of some factors that may influencethe selection of protective gloves for a workplace.� Type of chemicals handled.� Nature of contact (total immersion, splash, etc.).� Duration of contact.� Area requiring protection (hand only, forearm, arm).� Grip requirements (dry, wet, oily).� Thermal protection.� Size and comfort.� Abrasion/resistance requirements.

Gloves made from a wide variety of materials are designed formany types of workplace hazards. In general, gloves fall into fourgroups:� Gloves made of leather, canvas or metal mesh;� Fabric and coated fabric gloves;� Chemical- and liquid-resistant gloves;� Insulating rubber gloves (See 29 CFR 1910.137 and the following

section on electrical protective equipment for detailed require-ments on the selection, use and care of insulating rubber gloves).

Leather, Canvas or Metal Mesh GlovesSturdy gloves made from metal mesh, leather or canvas provide

protection against cuts and burns. Leather or canvass gloves alsoprotect against sustained heat.

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� Leather gloves protect against sparks, moderate heat, blows,chips and rough objects.

� Aluminized gloves provide reflective and insulating protectionagainst heat and require an insert made of synthetic materials toprotect against heat and cold.

� Aramid fiber gloves protect against heat and cold, are cut- andabrasive-resistant and wear well.

� Synthetic gloves of various materials offer protection againstheat and cold, are cut- and abrasive-resistant and may withstandsome diluted acids. These materials do not stand up againstalkalis and solvents.

Fabric and Coated Fabric GlovesFabric and coated fabric gloves are made of cotton or other

fabric to provide varying degrees of protection.� Fabric gloves protect against dirt, slivers, chafing and abrasions.

They do not provide sufficient protection for use with rough,sharp or heavy materials. Adding a plastic coating willstrengthen some fabric gloves.

� Coated fabric gloves are normally made from cotton flannel withnapping on one side. By coating the unnapped side with plastic,fabric gloves are transformed into general-purpose handprotection offering slip-resistant qualities. These gloves are usedfor tasks ranging from handling bricks and wire to chemicallaboratory containers. When selecting gloves to protect againstchemical exposure hazards, always check with the manufactureror review the manufacturer’s product literature to determine thegloves’ effectiveness against specific workplace chemicals andconditions.

Chemical- and Liquid-Resistant GlovesChemical-resistant gloves are made with different kinds of

rubber: natural, butyl, neoprene, nitrile and fluorocarbon (viton); orvarious kinds of plastic: polyvinyl chloride (PVC), polyvinyl alcoholand polyethylene. These materials can be blended or laminated for

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better performance. As a general rule, the thicker the glovematerial, the greater the chemical resistance but thick gloves mayimpair grip and dexterity, having a negative impact on safety.

Some examples of chemical-resistant gloves include: � Butyl gloves are made of a synthetic rubber and protect against

a wide variety of chemicals, such as peroxide, rocket fuels,highly corrosive acids (nitric acid, sulfuric acid, hydrofluoric acidand red-fuming nitric acid), strong bases, alcohols, aldehydes,ketones, esters and nitrocompounds. Butyl gloves also resistoxidation, ozone corrosion and abrasion, and remain flexible atlow temperatures. Butyl rubber does not perform well withaliphatic and aromatic hydrocarbons and halogenated solvents.

� Natural (latex) rubber gloves are comfortable to wear, whichmakes them a popular general-purpose glove. They featureoutstanding tensile strength, elasticity and temperatureresistance. In addition to resisting abrasions caused by grindingand polishing, these gloves protect workers’ hands from mostwater solutions of acids, alkalis, salts and ketones. Latex gloveshave caused allergic reactions in some individuals and may notbe appropriate for all employees. Hypoallergenic gloves, gloveliners and powderless gloves are possible alternatives forworkers who are allergic to latex gloves.

� Neoprene gloves are made of synthetic rubber and offer goodpliability, finger dexterity, high density and tear resistance. Theyprotect against hydraulic fluids, gasoline, alcohols, organic acidsand alkalis. They generally have chemical and wear resistanceproperties superior to those made of natural rubber.

� Nitrile gloves are made of a copolymer and provide protectionfrom chlorinated solvents such as trichloroethylene and per-chloroethylene. Although intended for jobs requiring dexterityand sensitivity, nitrile gloves stand up to heavy use even afterprolonged exposure to substances that cause other gloves todeteriorate. They offer protection when working with oils,greases, acids, caustics and alcohols but are generally notrecommended for use with strong oxidizing agents, aromaticsolvents, ketones and acetates.

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The following table from the U.S. Department of Energy(Occupational Safety and Health Technical Reference Manual) ratesvarious gloves as being protective against specific chemicals andwill help you select the most appropriate gloves to protect youremployees. The ratings are abbreviated as follows: VG: Very Good;G: Good; F: Fair; P: Poor (not recommended). Chemicals markedwith an asterisk (*) are for limited service.

Table 4Chemical Resistance Selection Chart for Protective Gloves

Chemical Neoprene Latex/Rubber Butyl Nitrile

Acetaldehyde* VG G VG GAcetic acid VG VG VG VGAcetone* G VG VG PAmmonium hydroxide VG VG VG VGAmy acetate* F P F PAniline G F F PBenzaldehyde* F F G GBenzene* P P P FButyl acetate G F F PButyl alcohol VG VG VG VGCarbon disulfide F F F FCarbon tetrachloride* F P P GCastor oil F P F VGChlorobenzene* F P F PChloroform* G P P FChloronaphthalene F P F FChromic acid (50%) F P F FCitric acid (10%) VG VG VG VGCyclohexanol G F G VGDibutyl phthalate* G P G GDiesel fuel G P P VGDiisobutyl ketone P F G PDimethylformamide F F G GDioctyl phthalate G P F VGDioxane VG G G G

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Table 4 (continued) Chemical Resistance Selection Chart for Protective Gloves

Epoxy resins, dry VG VG VG VGEthyl acetate* G F G FEthyl alcohol VG VG VG VGEthyl ether* VG G VG GEthylene dichloride* F P F PEthylene glycol VG VG VG VGFormaldehyde VG VG VG VGFormic acid VG VG VG VGFreon 11 G P F GFreon 12 G P F GFreon 21 G P F GFreon 22 G P F GFurfural* G G G GGasoline, leaded G P F VGGasoline, unleaded G P F VGGlycerin VG VG VG VGHexane F P P GHydrazine (65%) F G G GHydrochloric acid VG G G GHydrofluoric acid (48%) VG G G GHydrogen peroxide (30%) G G G GHydroquinone G G G FIsooctane F P P VGKerosene VG F F VGKetones G VG VG PLacquer thinners G F F PLactic acid (85%) VG VG VG VGLauric acid (36%) VG F VG VGLineolic acid VG P F GLinseed oil VG P F VGMaleic acid VG VG VG VGMethyl alcohol VG VG VG VGMethylamine F F G GMethyl bromide G F G FMethyl chloride* P P P P

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Methyl ethyl ketone* G G VG PMethyl isobutyl ketone* F F VG PMethyl metharcrylate G G VG FMonoethanolamine VG G VG VGMorpholine VG VG VG GNaphthalene G F F GNapthas, aliphatic VG F F VGNapthas, aromatic G P P GNitric acid* G F F FNitric acid, red and whitefuming P P P P

Nitromethane (95.5%)* F P F FNitropropane (95.5%) F P F FOctyl alcohol VG VG VG VGOleic acid VG F G VGOxalic acid VG VG VG VGPalmitic acid VG VG VG VGPerchloric acid (60%) VG F G GPerchloroethylene F P P GPetroleum distillates(naphtha) G P P VG

Phenol VG F G FPhosphoric acid VG G VG VGPotassium hydroxide VG VG VG VGPropyl acetate G F G FPropyl alcohol VG VG VG VGPropyl alcohol (iso) VG VG VG VGSodium hydroxide VG VG VG VGStyrene P P P FStyrene (100%) P P P FSulfuric acid G G G GTannic acid (65) VG VG VG VGTetrahydrofuran P F F FToluene* F P P FToluene diisocyanate (TDI) F G G F

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Trichloroethylene* F F P GTriethanolamine (85%) VG G G VGTung oil VG P F VGTurpentine G F F VGXylene* P P P F

Note: When selecting chemical-resistant gloves be sure to consult themanufacturer’s recommendations, especially if the gloved hand(s) willbe immersed in the chemical.

Care of Protective GlovesProtective gloves should be inspected before each use to ensure

that they are not torn, punctured or made ineffective in any way. Avisual inspection will help detect cuts or tears but a more thoroughinspection by filling the gloves with water and tightly rolling the cufftowards the fingers will help reveal any pinhole leaks. Gloves thatare discolored or stiff may also indicate deficiencies caused byexcessive use or degradation from chemical exposure.

Any gloves with impaired protective ability should be discardedand replaced. Reuse of chemical-resistant gloves should beevaluated carefully, taking into consideration the absorptivequalities of the gloves. A decision to reuse chemically-exposedgloves should take into consideration the toxicity of the chemicalsinvolved and factors such as duration of exposure, storage andtemperature.

Body Protection

Employees who face possible bodily injury of any kind thatcannot be eliminated through engineering, work practice or admin-istrative controls, must wear appropriate body protection whileperforming their jobs. In addition to cuts and radiation, thefollowing are examples of workplace hazards that could causebodily injury:� Temperature extremes;� Hot splashes from molten metals and other hot liquids;

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� Potential impacts from tools, machinery and materials;� Hazardous chemicals.

There are many varieties of protective clothing available forspecific hazards. Employers are required to ensure that theiremployees wear personal protective equipment only for the partsof the body exposed to possible injury. Examples of bodyprotection include laboratory coats, coveralls, vests, jackets, aprons,surgical gowns and full body suits.

If a hazard assessment indicates a need for full body protectionagainst toxic substances or harmful physical agents, the clothingshould be carefully inspected before each use, it must fit eachworker properly and it must function properly and for the purposefor which it is intended.

Protective clothing comes in a variety of materials, each effectiveagainst particular hazards, such as:� Paper-like fiber used for disposable suits provide protection

against dust and splashes.� Treated wool and cotton adapts well to changing temperatures,

is comfortable, and fire-resistant and protects against dust,abrasions and rough and irritating surfaces.

� Duck is a closely woven cotton fabric that protects against cutsand bruises when handling heavy, sharp or rough materials.

� Leather is often used to protect against dry heat and flames. � Rubber, rubberized fabrics, neoprene and plastics protect against

certain chemicals and physical hazards. When chemical orphysical hazards are present, check with the clothing manufac-turer to ensure that the material selected will provide protectionagainst the specific hazard.

Hearing Protection

Determining the need to provide hearing protection foremployees can be challenging. Employee exposure to excessivenoise depends upon a number of factors, including:� The loudness of the noise as measured in decibels (dB).� The duration of each employee’s exposure to the noise.� Whether employees move between work areas with different

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� Whether noise is generated from one or multiple sources.

Generally, the louder the noise, the shorter the exposure timebefore hearing protection is required. For instance, employees may beexposed to a noise level of 90 dB for 8 hours per day (unless theyexperience a Standard Threshold Shift) before hearing protection isrequired. On the other hand, if the noise level reaches 115 dB hearingprotection is required if the anticipated exposure exceeds 15 minutes.

For a more detailed discussion of the requirements for a com-prehensive hearing conservation program, see OSHA Publication3074 (2002), “Hearing Conservation” or refer to the OSHA standardat 29 CFR 1910.95, Occupational Noise Exposure, section (c).

Table 5, below, shows the permissible noise exposures thatrequire hearing protection for employees exposed to occupationalnoise at specific decibel levels for specific time periods. Noises areconsidered continuous if the interval between occurrences of themaximum noise level is one second or less. Noises not meetingthis definition are considered impact or impulse noises (loudmomentary explosions of sound) and exposures to this type ofnoise must not exceed 140 dB. Examples of situations or tools thatmay result in impact or impulse noises are powder-actuated nailguns, a punch press or drop hammers.

Table 5Permissible Noise Exposures

Duration per day, in hours Sound level in dB*

8 906 924 953 972 100

11/2 1021 105

1/2 1101/4 or less 115

*When measured on the A scale of a standard sound level meter at slow response.Source: 29 CFR 1910.95, Table G-16.

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If engineering and work practice controls do not lower employeeexposure to workplace noise to acceptable levels, employees mustwear appropriate hearing protection. It is important to understandthat hearing protectors reduce only the amount of noise that getsthrough to the ears. The amount of this reduction is referred to asattenuation, which differs according to the type of hearingprotection used and how well it fits. Hearing protectors worn byemployees must reduce an employee’s noise exposure to within theacceptable limits noted in Table 5. Refer to Appendix B of 29 CFR1910.95, Occupational Noise Exposure, for detailed information onmethods to estimate the attenuation effectiveness of hearingprotectors based on the device’s noise reduction rating (NRR).Manufacturers of hearing protection devices must display thedevice’s NRR on the product packaging. If employees are exposedto occupational noise at or above 85 dB averaged over an eight-hour period, the employer is required to institute a hearing conser-vation program that includes regular testing of employees’ hearingby qualified professionals. Refer to 29 CFR 1910.95(c) for adescription of the requirements for a hearing conservation program.

Some types of hearing protection include:� Single-use earplugs are made of waxed cotton, foam, silicone

rubber or fiberglass wool. They are self-forming and, whenproperly inserted, they work as well as most molded earplugs.

� Pre-formed or molded earplugs must be individually fitted by aprofessional and can be disposable or reusable. Reusable plugsshould be cleaned after each use.

� Earmuffs require a perfect seal around the ear. Glasses, facialhair, long hair or facial movements such as chewing may reducethe protective value of earmuffs.

OSHA Assistance

OSHA can provide extensive help through a variety of programs,including technical assistance about effective safety and healthprograms, state plans, workplace consultations, voluntaryprotection programs, strategic partnerships, training and education,and more. An overall commitment to workplace safety and healthcan add value to your business, to your workplace and to your life.

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Safety and Health Program Management GuidelinesEffective management of worker safety and health protection is

a decisive factor in reducing the extent and severity of work-relatedinjuries and illnesses and their related costs. In fact, an effectivesafety and health program forms the basis of good workerprotection and can save time and money (about $4 for every dollarspent) and increase productivity and reduce worker injuries,illnesses and related workers’ compensation costs.

To assist employers and employees in developing effectivesafety and health programs, OSHA published recommended Safetyand Health Program Management Guidelines (Federal Register 54(16): 3904-3916, January 26, 1989). These voluntary guidelinesapply to all places of employment covered by OSHA.

The guidelines identify four general elements critical to thedevelopment of a successful safety and health managementprogram:� Management leadership and employee involvement.� Work analysis.� Hazard prevention and control.� Safety and health training.

The guidelines recommend specific actions, under each of thesegeneral elements, to achieve an effective safety and healthprogram. The Federal Register notice is available online atwww.osha.gov.

State ProgramsThe Occupational Safety and Health Act of 1970 (OSH Act)

encourages states to develop and operate their own job safety andhealth plans. OSHA approves and monitors these plans. There arecurrently 26 state plans: 23 cover both private and public (state andlocal government) employment; 3 states, Connecticut, New Jerseyand New York, cover the public sector only. States and territorieswith their own OSHA-approved occupational safety and healthplans must adopt standards identical to, or at least as effective as,the federal standards.

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Consultation ServicesConsultation assistance is available on request to employers

who want help in establishing and maintaining a safe and healthfulworkplace. Largely funded by OSHA, the service is provided at nocost to the employer. Primarily developed for smaller employerswith more hazardous operations, the consultation service isdelivered by state governments employing professional safety andhealth consultants. Comprehensive assistance includes an appraisalof all-mechanical systems, work practices and occupational safetyand health hazards of the workplace and all aspects of theemployer’s present job safety and health program. In addition, theservice offers assistance to employers in developing and imple-menting an effective safety and health program. No penalties areproposed or citations issued for hazards identified by theconsultant. OSHA provides consultation assistance to the employerwith the assurance that his or her name and firm and anyinformation about the workplace will not be routinely reported toOSHA enforcement staff.

Under the consultation program, certain exemplary employersmay request participation in OSHA's Safety and HealthAchievement Recognition Program (SHARP). Eligibility for participa-tion in SHARP includes receiving a comprehensive consultationvisit, demonstrating exemplary achievements in workplace safetyand health by abating all identified hazards and developing anexcellent safety and health program.

Employers accepted into SHARP may receive an exemptionfrom programmed inspections (not complaint or accident investiga-tion inspections) for a period of one year. For more informationconcerning consultation assistance, see the OSHA website atwww.osha.gov.

Voluntary Protection Programs (VPP)Voluntary Protection Programs and onsite consultation services,

when coupled with an effective enforcement program, expandworker protection to help meet the goals of the OSH Act. The threelevels of VPP are Star, Merit, and Demonstration designed torecognize outstanding achievements by companies that have suc-cessfully incorporated comprehensive safety and health programsinto their total management system. The VPPs motivate others toachieve excellent safety and health results in the same outstanding

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way as they establish a cooperative relationship betweenemployers, employees and OSHA.

For additional information on VPP and how to apply, contact theOSHA regional offices listed at the end of this publication.

Strategic Partnership ProgramOSHA’s Strategic Partnership Program, the newest member

of OSHA’s cooperative programs, helps encourage, assist andrecognize the efforts of partners to eliminate serious workplacehazards and achieve a high level of worker safety and health.Whereas OSHA’s Consultation Program and VPP entail one-on-onerelationships between OSHA and individual worksites, moststrategic partnerships seek to have a broader impact by buildingcooperative relationships with groups of employers andemployees. These partnerships are voluntary, cooperative relation-ships between OSHA, employers, employee representatives andothers (e.g., trade unions, trade and professional associations, universities and other government agencies).

For more information on this and other cooperative programs,contact your nearest OSHA office, or visit OSHA’s website atwww.osha.gov.

Alliance ProgramsThe Alliance Program enables organizations committed to

workplace safety and health to collaborate with OSHA to preventinjuries and illnesses in the workplace. OSHA and the Alliance participants work together to reach out to, educate and lead thenation’s employers and their employees in improving andadvancing workplace safety and health.

Alliances are open to all groups, including trade or professionalorganizations, businesses, labor organizations, educational institu-tions and government agencies. In some cases, organizations maybe building on existing relationships with OSHA that weredeveloped through other cooperative programs.

There are few formal program requirements for Alliances and the agreements do not include an enforcement component.However, OSHA and the participating organizations must define,implement and meet a set of short- and long-term goals that fallinto three categories: training and education; outreach and commu-

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nication; and promoting the national dialogue on workplace safetyand health.

OSHA Training and EducationOSHA area offices offer a variety of information services, such as

compliance assistance, technical advice, publications, audiovisualaids and speakers for special engagements. OSHA’s TrainingInstitute in Arlington Heights, Ill., provides basic and advancedcourses in safety and health for federal and state complianceofficers, state consultants, federal agency personnel, and privatesector employers, employees and their representatives.

The OSHA Training Institute also has established OSHA TrainingInstitute Education Centers to address the increased demand for itscourses from the private sector and from other federal agencies.These centers are nonprofit colleges, universities and other organi-zations that have been selected after a competition for participationin the program.

OSHA also provides funds to nonprofit organizations, throughgrants, to conduct workplace training and education in subjectswhere OSHA believes there is a lack of workplace training. Grantsare awarded annually. Grant recipients are expected to contribute20 percent of the total grant cost.

For more information on grants, training and education, contactthe OSHA Training Institute, Office of Training and Education, 2020South Arlington Heights Road, Arlington Heights, IL 60005, (847)297-4810 or see “Outreach” on OSHA’s website at www.osha.gov.For further information on any OSHA program, contact your nearestOSHA area or regional office listed at the end of this publication.

Information Available ElectronicallyOSHA has a variety of materials and tools available on its

website at www.osha.gov. These include e-Tools such as ExpertAdvisors, Electronic Compliance Assistance Tools (e-cats), TechnicalLinks; regulations, directives and publications, videos and otherinformation for employers and employees. OSHA’s softwareprograms and compliance assistance tools walk you throughchallenging safety and health issues and common problems to findthe best solutions for your workplace.

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OSHA’s CD-ROM includes standards, interpretations, directivesand more, and can be purchased on CD-ROM from the U.S.Government Printing Office. To order, write to the Superintendentof Documents, P.O. Box 371954, Pittsburgh, PA 15250-7954 or phone(202) 512-1800, or order online at http://bookstore.gpo.gov.

OSHA PublicationsOSHA has an extensive publications program. For a listing of

free or sales items, visit OSHA’s website at www.osha.gov orcontact the OSHA Publications Office, U.S. Department of Labor,200 Constitution Avenue, NW, N-3101, Washington, DC 20210.Telephone (202) 693-1888 or fax to (202) 693-2498.

Contacting OSHATo report an emergency, file a complaint or seek OSHA advice,

assistance or products, call (800) 321-OSHA or contact your nearestOSHA regional or area office listed at the end of this publication.The teletypewriter (TTY) number is (877) 889-5627.

You can also file a complaint online and obtain moreinformation on OSHA federal and state programs by visitingOSHA’s website at www.osha.gov.

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OSHA Regional Offices

Region I

(CT,* ME, MA, NH, RI, VT*) JFK Federal Building, Room E340Boston, MA 02203(617) 565-9860

Region II

(NJ,* NY,* PR,* VI*)201 Varick Street, Room 670New York, NY 10014(212) 337-2378

Region III

(DE, DC, MD,* PA,* VA,* WV)The Curtis Center170 S. Independence Mall WestSuite 740 WestPhiladelphia, PA 19106-3309(215) 861-4900

Region IV

(AL, FL, GA, KY,* MS, NC,* SC,* TN*)61 Forsyth Street, SWAtlanta, GA 30303(404) 562-2300

Region V

(IL, IN,* MI,* MN,* OH, WI)230 South Dearborn Street, Room 3244Chicago, IL 60604(312) 353-2220

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Region VI

(AR, LA, NM,* OK, TX)525 Griffin Street, Room 602Dallas, TX 75202(214) 767-4731 or 4736 x224

Region VII

(IA,* KS, MO, NE)City Center Square1100 Main Street, Suite 800Kansas City, MO 64105(816) 426-5861

Region VIII

(CO, MT, ND, SD, UT,* WY*)1999 Broadway, Suite 1690PO Box 46550Denver, CO 80201-6550(303) 844-1600

Region IX

(American Samoa, AZ,* CA,* HI, NV,* Northern Mariana Islands)71 Stevenson Street, Room 420San Francisco, CA 94105(415) 975-4310

Region X

(AK,* ID, OR,* WA*)1111 Third Avenue, Suite 715Seattle, WA 98101-3212(206) 553-5930

*These states and territories operate their own OSHA-approved job safetyand health programs (Connecticut, New Jersey and New York plans coverpublic employees only). States with approved programs must have astandard that is identical to, or at least as effective as, the federal standard.

Note: To get contact information for OSHA Area Offices, OSHA-approvedState Plans and OSHA Consultation Projects, please visit us online atwww.osha.gov or call us at 1-800-321-OSHA.

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Appendix AOSHA Standards that Require PPE

29 CFR 1910, General IndustryStandards that Require the Employer to Provide PPE:

1910.28 Safety requirements for scaffolds1910.66 Powered platforms for building maintenance1910.67 Vehicle-mounted elevating and rotating work platforms1910.94 Ventilation1910.119 Process safety management of highly hazardous

chemicals1910.120 Hazardous waste operations and emergency response1910.132 General requirements (personal protective equipment)1910.133 Eye and face protection1910.135 Occupational foot protection1910.136 Occupational foot protection1910.137 Electrical protective devices1910.138 Hand protection1910.139 Respiratory protection for M. tuberculosis1910.157 Portable fire extinguishers1910.160 Fixed extinguishing systems, general1910.183 Helicopters1910.218 Forging machines1910.242 Hand and portable powered tools and equipment,

general1910.243 Guarding of portable power tools1910.252 General requirements (welding, cutting and brazing)1910.261 Pulp, paper, and paperboard mills1910.262 Textiles1910.268 Telecommunications1910.269 Electric power generation, transmission and distribution1910.333 Selection and use of work practices1910.335 Safeguards for personnel protection1910.1000 Air contaminants1910.1003 13 carcinogens, etc.1910.1017 Vinyl chloride1910.1029 Coke oven emissions1910.1043 Cotton dust1910.1096 Ionizing radiation

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Standards that Require the Employer to Provide PPE

at No Cost to the Employee:

1910.95 Occupational noise exposure1910.134 Respiratory protection1910.146 Permit-required confined spaces1910.156 Fire brigades 1910.266 Logging operations1910.1001 Asbestos1910.1018 Inorganic Arsenic1910.1025 Lead1910.1027 Cadmium1910.1028 Benzene1910.1030 Bloodborne pathogens1910.1044 1,2-dibromo-3-chloropropane1910.1045 Acrylonitrile1910.1047 Ethylene oxide1910.1048 Formaldehyde1910.1050 Methylenedianiline1910.1051 1,3-Butadiene1910.1052 Methylene chloride1910.1450 Occupational exposure to chemicals in laboratories

29 CFR 1915, Shipyard EmploymentStandards that Require the Employer to Provide PPE:

1915.12 Precautions and the order of testing before entering confined and enclosed spaces and other dangerous atmospheres

1915.13 Cleaning and other cold work1915.32 Toxic cleaning solvents1915.34 Mechanical paint removers1915.35 Painting1915.51 Ventilation and protection in welding, cutting and

heating1915.73 Guarding of deck openings and edges1915.77 Working surfaces1915.135 Powder actuated fastening tools1915.156 Foot protection1915.157 Hand and body protection1915.158 Lifesaving equipment1915.159 Personal fall arrest systems (PFAS)

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1915.154 Respiratory Protection1915.1001 Asbestos

29 CFR 1917, Marine TerminalsStandards that Require the Employer to Provide PPE:

1917.22 Hazardous cargo1917.25 Fumigants, pesticides, insecticides and hazardous waste1917.26 First aid and lifesaving facilities1917.91 Eye and face protection1917.93 Head protection1917.95 Other protective measures1917.126 River banks1917.152 Welding, cutting and heating (hot work)1917.154 Compressed air



1917.92 Respiratory protection

29 CFR 1918, LongshoringStandards that Require the Employer to Provide PPE:

1918.85 Containerized cargo operations1918.88 Log operations1918.93 Hazardous atmospheres and substances1918.94 Ventilation and atmospheric conditions1918.104 Foot protection1918.105 Other protective measures



1918.102 Respiratory protection

29 CFR 1926, ConstructionStandards that Require the Employer to Provide PPE:

1926.28 Personal protective equipment1926.52 Occupational noise exposure

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1926.57 Ventilation1926.64 Process safety management of highly hazardous

chemicals1926.65 Hazardous waste operations and emergency response1926.95 Criteria for personal protective equipment1926.96 Occupational foot protection1926.100 Head protection1926.101 Hearing protection1926.102 Eye and face protection1926.104 Safety belts, lifelines and lanyards1926.105 Safety nets1926.106 Working over or near water1926.250 General requirements for storage1926.300 General requirements (Hand and power tools)1926.302 Power-operated hand tools1926.304 Woodworking tools1926.353 Ventilation and protection in welding, cutting and

heating1926.354 Welding, cutting and heating in way of preservative

coatings1926.416 General requirements (Electrical)1926.451 General requirements (Scaffolds)1926.453 Aerial lifts1926.501 Duty to have fall protection1926.502 Fall protection systems criteria and practices1926.550 Cranes and derricks1926.551 Helicopters1926.701 General requirements (Concrete and masonry

construction)1926.760 Fall protection (Steel erection)1926.800 Underground construction1926.951 Tools and protective equipment1926.955 Overhead lines1926.1101 Asbestos



1926.60 Methylenedianiline1926.62 Lead1926.103 Respiratory protection1926.1127 Cadmium

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www.osha.gov

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Ground-Fault Protectionon Construction SitesU.S. Department of LaborOccupational Safety and Health Administration


393

This informational booklet isintended to provide a generic,non-exhaustive overview of aparticular standards-related topic.This publication does not itselfalter or determine complianceresponsibilities, which are setforth in OSHA standards them-selves and the OccupationalSafety and Health Act. Moreover,because interpretations andenforcement policy may changeover time, for additional guidanceon OSHA compliance require-ments, the reader should consultcurrent and administrative inter-pretations and decisions by theOccupational Safety and HealthReview Commission and theCourts

Material contained in this publica-tion is in the public domain andmay be reproduced, fully orpartially, without permission ofthe Federal Government. Sourcecredit is requested but notrequired.

This information will be madeavailable to sensory impairedindividuals upon request.

Voice phone: (202) 219-8615;TDD message referral phone:1-800-326-2577

394

Ground-Fault Protectionon Construction SitesU.S. Department of LaborAlexis M. Herman, Secretary

Occupational Safety and Health AdministrationCharles N. Jeffress, Assistant Secretary


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Ground-Fault Protection on Construction Sites

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Contents

Contents iii

Page

Why Does OSHA Have an Electrical Standard for Construction? ...................................................................... 1

What is a GFCI? ..................................................................... 3

What are Some Other Ways to Prevent Electrical Injury? ................................................................. 4

How Can Employers Protect Their Workers? ........................ 6

What is the Assured Equipment Grounding Conductor Program? ........................................................... 7

What Other Help Can OSHA Provide? .................................... 8Safety and Health Program Management Guidelines............ 8State Programs ....................................................................... 8Consultation Services ............................................................ 9Voluntary Protection Programs .............................................. 9Training and Education........................................................ 10Electronic Information......................................................... 10Emergencies......................................................................... 11

Equipment Grounding Conductor Program .......................... 12

Appendix—29 CFR Part 1926 Safety and Health Regulations for Construction Subpart K (partial) ............. 13

Related OSHA Publications ................................................. 15

States with Approved Plans ................................................ 16

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Page

OSHA Consultation Project Directory ................................. 19

OSHA Area Offices ............................................................... 21

OSHA Regional Offices ........................................................ 23

398

Why Does OSHA Have an Electrical Standard for Construction?

Why Does OSHA Have an Electrical Standard for Construction? 1

With the wide use of portable tools on construction sites, the use offlexible cords often becomes necessary. Hazards are created when cords,cord connectors, receptacles, and cord- and plug-connected equipmentare improperly used and maintained. Generally, flexible cords are morevulnerable to damage than is fixed wiring. Flexible cords must beconnected to devices and to fittings so as to prevent tension at joints andterminal screws. Because a cord is exposed, flexible and unsecuredjoints and terminals become more vulnerable. Flexible cord conductorsare finely stranded for flexibility, but the strands of one conductor mayloosen from under terminal screws and touch another conductor,especially if the cord is subjected to stress or strain.

A flexible cord may be damaged by activities on the job, by door orwindow edges, by staples or fastenings, by abrasion from adjacentmaterials, or simply by aging. If the electrical conductors becomeexposed, there is a danger of shocks, burns, or fire. A frequent hazard ona construction site is a cord assembly with improperly connectedterminals.

Also, when a cord connector is wet, hazardous leakage can occur tothe equipment grounding conductor and to humans who pick up thatconnector if they also provide a path to ground. Such leakage is notlimited to the face of the connector but also develops at any wet portionof it.

When the leakage current of tools is below 1 ampere, and the ground-ing conductor has a low resistance, no shock should be perceived.However, should the resistance of the equipment grounding conductorincrease, the current through the body also will increase. Thus, if theresistance of the equipment grounding conductor is significantly greaterthan 1 ohm, tools with even small leakages become hazardous.

The Occupational Safety and Health Administration’s (OSHA)electrical standard for construction, title 29 Code of Federal RegulationsPart 1926, Subpart K, contains the requirements for ground fault circuitinterrupters (GFCIs) and for assured equipment grounding conductorprograms which are included in the Appendix of this booklet. Theserequirements will help reduce the number of injuries and accidents fromelectrical hazards. Work disruptions should be minor, and the necessaryinspections and maintenance should require little time.

399


This booklet is intended to help employers and employees respon-sible for electrical equipment provide protection against 120-voltelectrical hazards on the construction site—the most common beingground fault electrical shock—through the use of GFCIs or throughthe assured equipment grounding conductor program.

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What is A GFCI?

A GFCI is a fast-acting circuit breaker that senses small imbal-ances in the circuit caused by current leakage to ground and, in afraction of a second, shuts off the electricity. The GFCI continuallymatches the amount of current going to an electrical device againstthe amount of current returning from the device along the electricalpath. Whenever the amount “going” differs from the amount “return-ing” by approximately 5 milliamps, the GFCI interrupts the electricpower within as little as 1/40 of a second. (See diagram.)

The GFCI, however, does not protect from line-to-line contacthazards—such as a worker holding two “hot” wires or a hot and aneutral wire in each hand. It protects against the most common formof electrical shock hazard—the ground fault, and protects againstfires, overheating, and destruction of insulation on wiring.

GFCIs can be used successfully to reduce electrical hazards onconstruction sites. Tripping of GFCIs—interrupting current flow—issometimes caused by wet connectors and tools. It is good practice tolimit exposure of connectors and tools to excessive moisture byusing watertight or sealable connectors.

Providing more GFCIs or shorter circuits can prevent trippingcaused by the cumulative leakage from several tools or by leakagesfrom extremely long circuits.

What is a GFCI? 3

401


Insulation and grounding are two recognized means ofpreventing injury during electrical equipment operation. Con-ductor insulation may be provided by placing nonconductivematerial such as plastic around the conductor. Grounding maybe achieved through the use of a direct connection to a knownground such as a metal, cold water pipe.

Consider, for example, the metal housing or enclosure arounda motor or the metal box in which electrical switches, circuitbreakers, and controls are placed. Such enclosures protect theequipment from dirt and moisture and prevent accidentalcontact with exposed wiring, however, there is a hazard associ-ated with housings and enclosures. A malfunction within theequipment—such as deteriorated insulation—may create anelectrical shock hazard. Many metal enclosures are connected toa ground to eliminate the hazard.

If a “hot” wire contacts a grounded enclosure, a ground faultresults which normally will trip a circuit breaker or blow a fuse.Metal enclosures and containers are usually grounded byconnecting them with a wire going to ground. This wire is calledan equipment grounding conductor. Most portable electric toolsand appliances are grounded by this means. There is one disad-vantage to grounding: a break in the grounding system mayoccur without the user’s knowledge.

Insulation may be damaged by hard usage on the job orsimply by aging. If this damage causes the conductors tobecome exposed, the hazards of shocks, burns, and fire willexist. Double insulation may be used as additional protection onthe live parts of a tool, but double insulation does not provideprotection against defective cords and plugs or against heavymoisture conditions.

What Are Some Other Ways to Prevent Electrical Injury?4

402

What Are Some Other Ways to Prevent Electrical Injury?

GFCI monitors the difference in current flowing into the “hot”and out to the grounded neutral conductors. The difference (1/

2ampere in this case) will flow back through any available path,such as the equipment grounding conductor, and through aperson holding the tool, if the person is in contact with agrounded object.

120-v 60 HzElectric SupplyService

GFCI“HotConductor”

11/2 Amperes“going” to tool

Fault developedwithin tool from“hot” conductor tometallic tool case

MOTOR1 Ampere“returning”from tool

Grounded neutral

Leakagecurrent

Equipmentgroundingconductor

Ground

Leakage current

Ground-Fault Circuit Interrupter

5

403


OSHA ground-fault protection rules and regulations have beendetermined necessary and appropriate for employee safety andhealth. Therefore, it is the employer’s responsibility to provideeither: (a) GFCIs on construction sites for receptacle outlets in useand not part of the permanent wiring of the building or structure; or(b) a scheduled and recorded assured equipment grounding conduc-tor program on construction sites, covering all cord sets, receptacleswhich are not part of the permanent wiring of the building or struc-ture, and equipment connected by cord and plug which are availablefor use or used by employees.

The employer is required to provide approved GFCIs for all l20-volt, single-phase, 15- and 20-ampere receptacle outlets on construc-tion sites that are not a part of the permanent wiring of the buildingor structure and that are in use by employees. If a receptacle orreceptacles are installed as part of the permanent wiring of thebuilding or structure and they are used for temporary electric power,GFCI protection shall be provided. Receptacles on the ends ofextension cords are not part of the permanent wiring and, thereforethe cord’s receptacle, must be of the GFCI type whether or not theextension cord is plugged into permanent wiring. These GFCIsmonitor the current-to-the-load for leakage to ground.

When this leakage exceeds 5 milliAmps plus or minus1 milliAmp, the GFCI interrupts the current. They are rated to tripquickly enough to prevent electrocution. This protection is requiredin addition to, not as a substitute for, the grounding requirements ofOSHA safety and health rules and regulations, 29 CFR 1926. Therequirements which the employer must meet, if he or chooses theGFCI option, are stated in 29 CFR 1926.404(b)(1)(ii).(See appendix.)

How Can Employers Protect Their Workers?6

404

The assured equipment grounding conductor program covers all cordsets, receptacles which are not a part of the permanent wiring of thebuilding or structure, and equipment connected by cord and plug whichare available for use or used by employees. The requirements which theprogram must meet are stated in 29 CFR 1926.404(b)(1)(iii), butemployers may provide additional tests or procedures. (See Appendix.)OSHA requires that a written description of the employer’s assuredequipment grounding conductor program, including the specific proce-dures adopted, be kept at the jobsite. This program should outline theemployer’s specific procedures for the required equipment inspections,tests, and test schedule. The required tests must be recorded, and therecord maintained until replaced by a more current record. The writtenprogram description and the recorded tests must be made available, atthe jobsite, to OSHA and to any affected employee upon request. Theemployer is required to designate one or more competent persons toimplement the program.

Electrical equipment noted in the assured equipment groundingconductor program must be visually inspected for damage or defectsbefore each day’s use. Any damaged or defective equipment must not beused by the employee until repaired.

Two tests are required by OSHA. One is a continuity test to ensurethat the equipment grounding conductor is electrically continuous. Itmust be performed on all cord sets, receptacles which are not part of thepermanent wiring of the building or structure, and on cord- and plug-connected equipment which is required to be grounded. This test may beperformed using a simple continuity tester, such as a lamp and battery, abell and battery, an ohmmeter, or a receptacle tester.

The other test must be performed on receptacles and plugs to ensurethat the equipment grounding conductor is connected to its properterminal. This test can be performed with the same equipment used inthe first test.

These tests are required before first use, after any repairs, afterdamage is suspected to have occurred, and at 3-month intervals. Cordsets and receptacles which are essentially fixed and not exposed todamage must be tested at regular intervals not to exceed 6 months. Anyequipment which fails to pass the required tests shall not be madeavailable or used by employees.

What Is the Assured Equipment Grounding Conductor Program?

What Is the Assured Equipment Grounding Conductor Program?

7

405


Equipment Grounding Conductor Program12

Employer Must Provide:

• Written Description of Program• Competent Person to Implement the Program• Inspection and Testing• Records of Test Results

Inspections

• Frequency of Inspections:- Before each day’s use.

• Visual inspection of the following equipment is required:- Cord sets.- Cap, plug and receptacle of

cord sets.- Equipment connected by

cord and plug.

• Exceptions:- Receptacles and cord setsthat are fixed and notexposed to damaged.

Tests

• Frequency of tests:- Before first use.- After repair and beforeplacing back in service.

- Before use after suspecteddamage.

- Every 3-months except thatcord sets and receptaclesexposed to damage must betested at regular intervalsnot to exceed 6 months.

• Conduct tests for:- Continuity of equipment ofgrounding conductor.

- Proper terminal connectionof equipment groundingconductor.

406

13

29 CFR Part 1926 Safety and Health Regulations forConstruction Subpart K (Partial)

§ 1926.404 wiring design and protection.(b) Branch circuits-(1) Ground-fault protection-(I) General.

The employer shall use either ground-fault circuit interrupters asspecified in paragraph (b)(1)(ii) of this section or an assured equip-ment grounding conductor program as specified in paragraph(b)(1)(iii) of this section to protect employees on construction sites.These requirements are in addition to any other requirements forequipment grounding conductors.

(ii) Ground-fault circuit interrupters. All l20-volt, single-phase,15- and 20-ampere receptacle outlets on construction sites, which arenot a part of the permanent wiring of the building or structure andwhich are in use by employees, shall have approved ground-faultcircuit interrupters for personnel protection. Receptacles on a two-wire, single-phase portable or vehicle-mounted generator rated notmore than 5kW, where the circuit conductors of the generator areinsulated from the generator frame and all other grounded surfaces,need not be protected with ground-fault circuit interrupters.

(iii) Assured equipment grounding conductor program. Theemployer shall establish and implement an assured equipmentgrounding conductor program on construction sites covering all cordsets, receptacles which are not a part of the building or structure, andequipment connected by cord and plug which are available for use orused by employees. This program shall comply with the followingminimum requirements:

(A) A written description of the program, including thespecific procedures adopted by the employer, shall be availableat the jobsite for inspection and copying by the AssistantSecretary and any affected employee.

(B) The employer shall designate one or more competentpersons (as defined in § 1926.32(f)) to implement the program.

(C) Each cord set, attachment cap, plug and receptacle ofcord sets, and any equipment connected by cord and plug, exceptcord sets and receptacles which are fixed and not exposed todamage, shall be visually inspected before each day’s use forexternal defects, such as deformed or missing pins or insulation

Appendix

Appendix

407


damage, and for indications of possible internal damage.Equipment found damaged or defective shall not be used untilrepaired.

(D) The following tests shall be performed on all cord sets,receptacles which are not a part of the permanent wiring of thebuilding or structure, and cord-and plug-connected equipmentrequired to be grounded:

(1) All equipment grounding conductors shall be tested forcontinuity and shall be electrically continuous.

(2) Each receptacle and attachment cap or plug shall be tested forcorrect attachment of the equipment grounding conductor. Theequipment grounding conductor shall be connected to its properterminal.

(E) All required tests shall be performed:(1) Before first use;(2) Before equipment is returned to service following anyrepairs;(3) Before equipment is used after any incident which canbe reasonably suspected to have caused damage (for example,when a cord set is run over); and(4) At intervals not to exceed 3 months, except that cordsets and receptacles which are fixed and not exposed to damageshall be tested at intervals not exceeding 6 months.(F) The employer shall not make available or permit the use by

employees of any equipment which has not met the requirements ofparagraph (b)(1)(iii) of this section.

(G) Tests performed as required in this paragraph shall be re-corded. This test record shall identify each receptacle, cord set, andcord- and plug-connected equipment that passed the test and shallindicate the last date it was tested or the interval for which it wastested. This record shall be kept by means of logs, color coding, orother effective means and shall be maintained until replaced by amore current record. The record shall be made available on thejobsite for inspection by the Assistant Secretary and any affectedemployee.

14

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409

410

Student Manual

WorkplaceSafety and Health

411

Ordering InformationTo receive documents or other information about occupational safety andhealth topics, contact the National Institute for Occupational Safety andHealth (NIOSH) at

NIOSH—Publications Dissemination4676 Columbia Parkway

Cincinnati, OH 45226–1998

Telephone: 1–800–35–NIOSH (1–800–356–4674)Fax number: 513–533–8573E-mail: [email protected]

or visit the NIOSH Web site at www.cdc.gov/niosh

This document is in the public domain and maybe freely copied or reprinted.

Disclaimer: Mention of any company or productdoes not constitute endorsement by NIOSH.

DHHS (NIOSH) Publication No. 2002-123

412

Student Manual

January 2002

413

ii

AcknowledgmentsThis document was prepared by Thaddeus W. Fowler, Ed.D., and Karen K.Miles, Ph.D., Education and Information Division (EID) of the NationalInstitute for Occupational Safety and Health (NIOSH). Editorial services wereprovided by John W. Diether. Pauline Elliott provided layout and design.

The authors wish to thank John Palassis and Diana Flaherty (NIOSH), RobertNester (formerly of NIOSH), and participating teachers and students for theircontributions to the development of this document.

414

ForewordThe National Institute for Occupational Safety and Health (NIOSH) estimatesthat 200,000 young workers under the age of 18 suffer work-related injuries inthe United States each year. Young and new workers have a high risk for work-related injury compared with more experienced workers. Occupational safety and health training remains a fundamental element of hazard control in the work-place, and there is great potential to reduce these incidents through pre-employ-ment training. Effective pre-employment training should include realistic envi-ronments and hands-on exercises. However, NIOSH recommends that actualemployment in the electrical trades or any of the other construction trades bedelayed until individuals reach the minimum age of 18.

This student manual is part of a safety and health curriculum for secondary andpost-secondary electrical trades courses. The manual is designed to engage thelearner in recognizing, evaluating, and controlling hazards associated with elec-trical work. It was developed through extensive research with vocational instruc-tors, and we are grateful for their valuable contributions.

Kathleen M. Rest, Ph.D., M.P.A.Acting DirectorNational Institute for Occupational Safety and Health

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Contents

Page

Section 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1Electricity Is Dangerous . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

How Is an Electrical Shock Received? . . . . . . . . . . . . . . . . . . . . . 2Summary of Section 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Section 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6Dangers of Electrical Shock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Summary of Section 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Section 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12Burns Caused by Electricity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Electrical Fires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14Summary of Section 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

First Aid Fact Sheet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

Section 4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18Overview of the Safety Model . . . . . . . . . . . . . . . . . . . . . . . . . . 18

What Must Be Done to Be Safe? . . . . . . . . . . . . . . . . . . . . . . . . . . 18Summary of Section 4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

Section 5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22Safety Model Stage 1—Recognizing Hazards . . . . . . . . . . . . . . . . . 22

How Do You Recognize Hazards? . . . . . . . . . . . . . . . . . . . . . . . . 22Inadequate wiring hazards . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24Exposed electrical parts hazards . . . . . . . . . . . . . . . . . . . . . . . 24Overhead powerline hazards . . . . . . . . . . . . . . . . . . . . . . . . . . 25Defective insulation hazards . . . . . . . . . . . . . . . . . . . . . . . . . . 26Improper grounding hazards . . . . . . . . . . . . . . . . . . . . . . . . . . 27Overload hazards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28Wet conditions hazards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29Additional hazards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30


Section 6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34Safety Model Stage 2—Evaluating Hazards . . . . . . . . . . . . . . . . . . 34

How Do You Evaluate Your Risk? . . . . . . . . . . . . . . . . . . . . . . . . 34Summary of Section 6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

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Page

Section 7 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36Safety Model Stage 3—Controlling Hazards:Safe Work Environment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

How Do You Control Hazards? . . . . . . . . . . . . . . . . . . . . . . . . . . . 36How Do You Create a Safe Work Environment? . . . . . . . . . . . . . . 36

Lock out and tag out circuits and equipment . . . . . . . . . . . . . . 37Lock-out/tag-out checklist . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38Control inadequate wiring hazards . . . . . . . . . . . . . . . . . . . . . 39Control hazards of fixed wiring . . . . . . . . . . . . . . . . . . . . . . . . 40Control hazards of flexible wiring . . . . . . . . . . . . . . . . . . . . . . 40

Use flexible wiring properly . . . . . . . . . . . . . . . . . . . . . . . . 40Use the right extension cord . . . . . . . . . . . . . . . . . . . . . . . . 42

Control hazards of exposed live electrical parts: isolateenergized components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43Control hazards of exposure to live electrical wires:use proper insulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44Control hazards of shocking currents . . . . . . . . . . . . . . . . . . . . 46

Ground circuits and equipment . . . . . . . . . . . . . . . . . . . . . . 46Use GFCI’s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48Bond components to assure grounding path . . . . . . . . . . . . 49

Control overload current hazards . . . . . . . . . . . . . . . . . . . . . . . 50Summary of Section 7 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52

Section 8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54

Safety Model Stage 3—Controlling Hazards:Safe Work Practices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54

How Do You Work Safely? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54Plan your work and plan for safety . . . . . . . . . . . . . . . . . . . . . 55Ladder safety fact sheet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58Avoid wet working conditions and other dangers . . . . . . . . . . . 61Avoid overhead powerlines . . . . . . . . . . . . . . . . . . . . . . . . . . . 61Use proper wiring and connectors . . . . . . . . . . . . . . . . . . . . . . 61Use and maintain tools properly . . . . . . . . . . . . . . . . . . . . . . . 64Wear correct PPE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66PPE fact sheet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68


Glossary of Terms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72

Endnotes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74

Appendix . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75

Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76

Photo and Graphics Credits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77

Contents (continued)

418

Section 1Electricity Is DangerousWhenever you work with power tools or on electrical circuits thereis a risk of electrical hazards, especially electrical shock. Anyonecan be exposed to these hazards at home or at work. Workers areexposed to more hazards because job sites can be cluttered withtools and materials, fast-paced, and open to the weather. Risk is alsohigher at work because many jobs involve electric power tools.

Electrical trades workers must pay special attention to electrical haz-ards because they work on electrical circuits. Coming in contact withan electrical voltage can cause current to flow through the body,resulting in electrical shock and burns. Serious injury or even deathmay occur. As a source of energy, electricity is used without muchthought about the hazards it can cause. Because electricity is a famil-iar part of our lives, it often is not treated with enough caution. As aresult, an average of one worker is electrocuted on the job every dayof every year! Electrocution is the third leading cause of work-related deaths among 16- and 17-year-olds, after motor vehicledeaths and workplace homicide. Electrocution is the cause of12% of all workplace deaths among young workers.1

❚ Electrical shock causes injury ordeath!

Section 1 Page 1

Electrical Safety

Electrical work can be deadly if not done safely.

Note to the learner —This manualdescribes the hazards of electrical workand basic approaches to working safely.You will learn skills to help you recognize,evaluate, and control electrical hazards.This information will prepare you for addi-tional safety training such as hands-onexercises and more detailed reviews ofregulations for electrical work.

Your employer, co-workers, and communitywill depend on your expertise. Start yourcareer off right by learning safe practicesand developing good safety habits. Safetyis a very important part of any job. Do itright from the start.

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This manual will present many topics. There are four main types ofelectrical injuries:electrocution (death due to electrical shock),electrical shock, burns, and falls. The dangers of electricity, electri-cal shock, and the resulting injuries will be discussed. The variouselectrical hazards will be described. You will learn about the SafetyModel, an important tool for recognizing, evaluating, and con-trolling hazards. Important definitions and notes are shown in themargins. Practices that will help keep you safe and free of injury areemphasized. To give you an idea of the hazards caused by electricity,case studies about real-life deaths will be described.

How Is an Electrical Shock Received?An electrical shock is received when electrical current passesthrough the body. Current will pass through the body in a variety ofsituations. Whenever two wires are at different voltages, current willpass between them if they are connected. Your body can connect thewires if you touch both of them at the same time. Current will passthrough your body.

In most household wiring, the black wires and the red wires are at120 volts. The white wires are at 0 volts because they are connectedto ground. The connection to ground is often through a conductingground rod driven into the earth. The connection can also be madethrough a buried metal water pipe. If you come in contact with an

❚ current— the movement ofelectrical charge

❚ voltage— a measure of electrical force

❚ circuit— a complete path for the flowof current

❚ You will receive a shock if youtouch two wires at differentvoltages at the same time.

❚ ground— a physical electrical con-nection to the earth

❚ energized (live, “hot”)— similarterms meaning that a voltage is present that can cause a current, sothere is a possibility of gettingshocked

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Wires carry current.

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energized black wire—and you are also in contact with the neu-tral white wire—current will pass through your body. You willreceive an electrical shock.

If you are in contact with a live wire or any live component of anenergized electrical device—and also in contact with anygrounded object—you will receive a shock. Plumbing is oftengrounded. Metal electrical boxes and conduit are grounded.

Your risk of receiving a shock is greater if you stand in a puddle ofwater. But you don’t even have to be standing in water to be at risk.Wet clothing, high humidity, and perspiration also increase yourchances of being electrocuted. Of course, there is always a chance ofelectrocution, even in dry conditions.

❚ conductor— material in which anelectrical current moves easily

❚ neutral —at ground potential (0 volts)because of a connection to ground

❚ You will receive a shock if you touch a live wire and aregrounded at the same time.

❚ When a circuit, electrical component, or equipment is energized, a potential shock hazard is present.

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I S DA N G E R O U S

Black and red wires are usually energized, and white wires are usually neutral.

Metal electrical boxes should be groundedto prevent shocks.

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Page 4 Section 1

You can even receive a shock when you are not in contact with anelectrical ground. Contact with both live wires of a 240-volt cablewill deliver a shock. (This type of shock can occur because one livewire may be at +120 volts while the other is at -120 volts during analternating current cycle—a difference of 240 volts.). You can alsoreceive a shock from electrical components that are not groundedproperly. Even contact with another person who is receiving an elec-trical shock may cause you to be shocked.

A 30-year-old male electrical technician was helping a company service representative test the volt-age-regulating unit on a new rolling mill. While the electrical technician went to get the equipmentservice manual, the service representative opened the panel cover of the voltage regulator’s con-

trol cabinet in preparation to trace the low-voltage wiring in question (the wiring was not color-coded). Theservice representative climbed onto a nearby cabinet in order to view the wires. The technician returnedand began working inside the control cabinet, near exposed energized electrical conductors. The techni-cian tugged at the low-voltage wires while the service representative tried to identify them from above.Suddenly, the representative heard the victim making a gurgling sound and looked down to see the victimshaking as though he were being shocked. Cardiopulmonary resuscitation (CPR) was administered to thevictim about 10 minutes later. He was pronounced dead almost 2 hours later as a result of his contact withan energized electrical conductor.

To prevent an incident like this, employers should take the following steps:

• Establish proper rules and procedures on how to access electrical control cabinets without gettinghurt.

• Make sure all employees know the importance of de-energizing (shutting off) electrical systems beforeperforming repairs.

• Equip voltage-regulating equipment with color-coded wiring.

• Train workers in CPR.

Amaintenance man rode 12 feet above the floor on a motorized lift to work on a 277-volt light fixture.He did not turn off the power supply to the lights. He removed the line fuse from the black wire,which he thought was the “hot” wire. But, because of a mistake in installation, it turned out that the

white wire was the “hot” wire, not the black one. The black wire was neutral. He began to strip the whitewire using a wire stripper in his right hand. Electricity passed from the “hot” white wire to the stripper, theninto his hand and through his body, and then to ground through his left index finger. A co-worker heard anoise and saw the victim lying face-up on the lift. She immediately summoned another worker, who low-ered the platform. CPR was performed, but the maintenance man could not be saved. He was pronounceddead at the scene.

You can prevent injuries and deaths by remembering the following points:

• If you work on an electrical circuit, test to make sure that the circuit is de-energized (shut off)!

• Never attempt to handle any wires or conductors until you are absolutely positive that their electricalsupply has been shut off.

• Be sure to lock out and tag out circuits so they cannot be re-energized.

• Always assume a conductor is dangerous.

E L E C T R I C I T Y

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Summary of Section 1 You will receive an electrical shock if a part of your body completesan electrical circuit by• • •

touching a live wire and an electrical ground, or

touching a live wire and another wire at a different voltage.

Section 1 Page 5

Always test a circuit to makesure it is de-energized beforeworking on it.

I S DA N G E R O U S

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Section 2Dangers of Electrical ShockThe severity of injury from electrical shock depends on the amountof electrical current and the length of time the current passesthrough the body. For example, 1/10 of an ampere (amp) of elec-tricity going through the body for just 2 seconds is enough to causedeath. The amount of internal current a person can withstand andstill be able to control the muscles of the arm and hand can be lessthan 10 milliamperes (milliamps or mA). Currents above 10 mAcan paralyze or “freeze” muscles. When this “freezing” happens, aperson is no longer able to release a tool, wire, or other object. Infact, the electrified object may be held even more tightly, resultingin longer exposure to the shocking current. For this reason, hand-held tools that give a shock can be very dangerous. If you can’t letgo of the tool, current continues through your body for a longertime, which can lead to respiratory paralysis (the muscles that con-trol breathing cannot move). You stop breathing for a period oftime. People have stopped breathing when shocked with currentsfrom voltages as low as 49 volts. Usually, it takes about 30 mA ofcurrent to cause respiratory paralysis.

Currents greater than 75 mA cause ventricular fibrillation (veryrapid, ineffective heartbeat). This condition will cause death within afew minutes unless a special device called a defibrillator is used tosave the victim. Heart paralysis occurs at 4 amps, which means theheart does not pump at all. Tissue is burned with currents greaterthan 5 amps.2

The table shows what usually happens for a range of currents (lasting one second) at typical household voltages. Longer exposuretimes increase the danger to the shock victim. For example, a cur-rent of 100 mA applied for 3 seconds is as dangerous as a current of 900 mA applied for a fraction of a second (0.03 seconds). The mus-cle structure of the person also makes a difference. People with lessmuscle tissue are typically affected at lower current levels. Even lowvoltages can be extremely dangerous because the degree of injurydepends not only on the amount of current but also on the length oftime the body is in contact with the circuit.

LOW VOLTAGE DOES NOT MEAN LOW HAZARD!

❚ ampere (amp)— the unit used tomeasure current

❚ milliampere (milliamp or mA)—1/1,000 of an ampere

❚ shocking current— electrical currentthat passes through a part of thebody

❚ You will be hurt more if you can’tlet go of a tool giving a shock.

❚ The longer the shock, the greaterthe injury.

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Defibrillator in use.

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Sometimes high voltages lead to additional injuries. High voltagescan cause violent muscular contractions. You may lose your balanceand fall, which can cause injury or even death if you fall intomachinery that can crush you. High voltages can also cause severeburns (as seen on pages 9 and 10).

At 600 volts, the current through the body may be as great as 4 amps, causing damage to internal organs such as the heart. Highvoltages also produce burns. In addition, internal blood vessels mayclot. Nerves in the area of the contact point may be damaged.Muscle contractions may cause bone fractures from either the con-tractions themselves or from falls.

A severe shock can cause much more damage to the body than isvisible. A person may suffer internal bleeding and destruction of tis-sues, nerves, and muscles. Sometimes the hidden injuries caused byelectrical shock result in a delayed death. Shock is often only thebeginning of a chain of events. Even if the electrical current is toosmall to cause injury, your reaction to the shock may cause you tofall, resulting in bruises, broken bones, or even death.

The length of time of the shock greatly affects the amount of injury.If the shock is short in duration, it may only be painful. A longer

❚ High voltages cause additionalinjuries!

❚ Higher voltages can cause largercurrents and more severe shocks.

❚ Some injuries from electricalshock cannot be seen.

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C T R I C A L S H O C K

Effects of Electrical Current* on the Body 3

Current Reaction

1 milliamp Just a faint tingle.

5 milliamps Slight shock felt. Disturbing, but not painful. Most people can “let go.”However, strong involuntary movements can cause injuries.

6–25 milliamps (women)† Painful shock. Muscular control is lost. This is the range where “freezing9–30 milliamps (men) currents” start. It may not be possible to “let go.”

50–150 milliamps Extremely painful shock, respiratory arrest (breathing stops), severe musclecontractions. Flexor muscles may cause holding on; extensor muscles maycause intense pushing away. Death is possible.

1,000–4,300 milliamps Ventricular fibrillation (heart pumping action not rhythmic) occurs. Muscles(1–4.3 amps) contract; nerve damage occurs. Death is likely.

10,000 milliamps Cardiac arrest and severe burns occur. Death is probable.(10 amps)

15,000 milliamps Lowest overcurrent at which a typical fuse or circuit breaker opens a circuit!(15 amps)

*Effects are for voltages less than about 600 volts. Higher voltages also cause severe burns.†Differences in muscle and fat content affect the severity of shock.

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shock (lasting a few seconds) could be fatal if the level of current ishigh enough to cause the heart to go into ventricular fibrillation.This is not much current when you realize that a small power drilluses 30 times as much current as what will kill. At relatively highcurrents, death is certain if the shock is long enough. However, ifthe shock is short and the heart has not been damaged, a normalheartbeat may resume if contact with the electrical current is elimi-nated. (This type of recovery is rare.)

The amount of currentpassing through the bodyalso affects the severity ofan electrical shock. Greatervoltages produce greatercurrents. So, there isgreater danger from highervoltages. Resistance hin-ders current. The lower theresistance (or impedance inAC circuits), the greater thecurrent will be. Dry skinmay have a resistance of100,000 ohms or more. Wetskin may have a resistanceof only 1,000 ohms. Wetworking conditions or bro-ken skin will drasticallyreduce resistance. The lowresistance of wet skinallows current to pass intothe body more easily andgive a greater shock. When more force is applied to the contact pointor when the contact area is larger, the resistance is lower, causingstronger shocks.

The path of the electrical current through the body affects the severi-ty of the shock. Currents through the heart or nervous system aremost dangerous. If you contact a live wire with your head, your nerv-ous system will be damaged. Contacting a live electrical part withone hand—while you are grounded at the other side of your body—will cause electrical current to pass across your chest, possibly injur-ing your heart and lungs.

❚ The greater the current, thegreater the shock!

❚ Severity of shock depends onvoltage, amperage, and resist-ance.

❚ resistance— a material's ability todecrease or stop electrical current

❚ ohm— unit of measurement for electrical resistance

❚ Lower resistance causes greatercurrents.

❚ Currents across the chest are verydangerous.

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DA N G E R S O F E L

Power drills use 30 times asmuch current as what will kill.

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❚ NEC—National Electrical Code—a comprehensive listing of practices to protect workers andequipment from electrical hazardssuch as fire and electrocution

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Amale service technician arrived at a customer’s house to perform pre-winter maintenance on an oilfurnace. The customer then left the house and returned 90 minutes later. She noticed the servicetruck was still in the driveway. After 2 more hours, the customer entered the crawl space with a

flashlight to look for the technician but could not see him. She then called the owner of the company, whocame to the house. He searched the crawl space and found the technician on his stomach, leaning on hiselbows in front of the furnace. The assistant county coroner was called and pronounced the techniciandead at the scene. The victim had electrical burns on his scalp and right elbow.

After the incident, an electrician inspected the site. A toggle switch that supposedly controlled electricalpower to the furnace was in the “off” position. The electrician described the wiring as “haphazard and confusing.”

Two weeks later, the county electrical inspector performed another inspection. He discovered that incor-rect wiring of the toggle switch allowed power to flow to the furnace even when the switch was in the “off”position. The owner of the company stated that the victim was a very thorough worker. Perhaps the victimperformed more maintenance on the furnace than previous technicians, exposing himself to the electricalhazard.

This death could have been prevented!

• The victim should have tested the circuit to make sure it was de-energized.

• Employers should provide workers with appropriate equipment and training. Using safety equipmentshould be a requirement of the job. In this case, a simple circuit tester may have saved the victim’s life.

• Residential wiring should satisfy the National Electrical Code (NEC). Although the NEC is not retroac-tive, all homeowners should make sure their systems are safe.

Electrical burn on hand and arm.

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DA N G E R S O F E L

There have been cases where an arm or leg is severely burned byhigh-voltage electrical current to the point of coming off, and the victim is not electrocuted. In these cases, the current passes throughonly a part of the limb before it goes out of the body and into anotherconductor. Therefore, the current does not go through the chest areaand may not cause death, even though the victim is severely disfig-ured. If the current does go through the chest, the person will almostsurely be electrocuted. A large number of serious electrical injuriesinvolve current passing from the hands to the feet. Such a pathinvolves both the heart and lungs. This type of shock is often fatal.

Page 10 Section 2

Arm with third degree burn from high-voltage line.

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Summary of Section 2The danger from electrical shock depends on• • •

the amountof the shocking current through the body,

the duration of the shocking current through the body, and

the path of the shocking current through the body.

E C T R I C A L S H O C K

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Section 3

Burns Caused by Electricity The most common shock-related, nonfatal injury is a burn. Burnscaused by electricity may be of three types: electrical burns, arcburns, and thermal contact burns. Electrical burns can result whena person touches electrical wiring or equipment that is used or main-tained improperly. Typically, suchburns occur on the hands.Electrical burns are one of themost serious injuries you canreceive. They need to be givenimmediate attention. Additionally,clothing may catch fire and athermal burn may result from theheat of the fire.

Arc-blasts occur when powerful,high-amperage currents arcthrough the air. Arcing is theluminous electrical discharge that occurs when high voltages existacross a gap between conductors and current travels through the air.This situation is often caused by equipment failure due to abuse orfatigue. Temperatures as high as 35,000°F have been reached in arc-blasts.

There are three primary hazards associated with an arc-blast.

(1) Arcing gives off thermal radiation (heat) and intense light, whichcan cause burns. Several factors affect the degree of injury, includ-ing skin color, area of skin exposed, and type of clothing worn.Proper clothing, work distances, and overcurrent protection canreduce the risk of such a burn.

(2) A high-voltage arc can produce a considerable pressure waveblast. A person 2 feet away from a 25,000-amp arc feels a force ofabout 480 pounds on the front of the body. In addition, such anexplosion can cause serious ear damage and memory loss due toconcussion. Sometimes the pressure wave throws the victim awayfrom the arc-blast. While this may reduce further exposure to the

❚ Electrical shocks cause burns.

❚ arc-blast— explosive release of moltenmaterial from equipment caused byhigh-amperage arcs

❚ arcing —the luminous electrical dis-charge (bright, electrical sparking)through the air that occurs when highvoltages exist across a gap betweenconductors

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Contact electrical burns. Theknee on the left was energized,and the knee on the right wasgrounded.

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thermal energy, serious physical injury may result. The pressurewave can propel large objects over great distances. In some cases,the pressure wave has enough force to snap off the heads of steelbolts and knock over walls.

(3) A high-voltage arc can also cause many of the copper and alu-minum components in electrical equipment to melt. These dropletsof molten metal can be blasted great distances by the pressure wave.Although these droplets harden rapidly, they can still be hot enoughto cause serious burns or cause ordinary clothing to catch fire, evenif you are 10 feet or more away.

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Five technicians were performing preventive maintenance on the electrical system of a railroad main-tenance facility. One of the technicians was assigned to clean the lower compartment of an electri-cal cabinet using cleaning fluid in an aerosol can. But, he began to clean the upper compartment as

well.The upper compartment was filled with live circuitry. When the clean-ing spray contacted the live circuitry, a conductive path for the currentwas created. The current passed through the stream of fluid, into thetechnician’s arm, and across his chest. The current caused a loudexplosion. Co-workers found the victim with his clothes on fire. Oneworker put out the fire with an extinguisher, and another pulled the vic-tim away from the compartment with a plastic vacuum cleaner hose.The paramedics responded in 5 minutes. Although the victim sur-vived the shock, he died 24 hours later of burns.

This death could have been prevented if the following precautionshad been taken:

• Before doing any electrical work, de-energize all circuits andequipment, perform lock-out/tag-out, and test circuits andequipment to make sure they are de-energized.

• The company should have trained the workers to performtheir jobs safely.

• Proper personal protective equipment (PPE) should alwaysbe used.

• Never use aerosol spray cans around high-voltage equipment.

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14 Section 3

Electrical Fires Electricity is one of the most commoncauses of fires and thermal burns inhomes and workplaces. Defective ormisused electrical equipment is amajor cause of electrical fires. Ifthere is a small electrical fire, besure to use only a Class C or multi-purpose (ABC) fire extinguisher, oryou might make the problem worse.All fire extinguishers are marked withletter(s) that tell you the kinds of fires theycan put out. Some extinguishers contain symbols, too.

The letters and symbols are explained below (including suggestions on how to remember them).

A (think: Ashes) = paper, wood, etc.

B (think: Barrel ) = flammable liquids

C (think: Circuits ) = electrical fires

Here are a couple of fire extinguishers at a worksite. Can you tell what types of fires they will put out?

This extinguisher can only be used on Class B and Class C fires.

This extinguisher can onlybe used on Class A andClass C fires.

B U R N S C AU S E D

Learn how to use fireextinguishers at work.

However, do not try to put out fires unless you have receivedproper training. If you are not trained, the best thing you cando is evacuate the area and call for help.

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Thermal burns may result if an explosion occurs when electricityignites an explosive mixture of material in the air. This ignition canresult from the buildup of combustible vapors, gasses, or dusts.Occupational Safety and Health Administration (OSHA) standards,the NEC, and other safety standards give precise safety requirementsfor the operation of electrical systems and equipment in such dan-gerous areas. Ignition can also be caused by overheated conductorsor equipment, or by normal arcing at switch contacts or in circuitbreakers.

Summary of Section 3 Burns are the most common injury caused by electricity. The threetypes of burns are• • •

electrical burns,

arc burns, and

thermal contact burns.

❚ OSHA—Occupational Safety andHealth Administration—the Federalagency in the U.S. Department ofLabor that establishes and enforcesworkplace safety and health regulations

B Y E L E C T R I C I T Y

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Page 16

Shut offthe electrical current if the victim is still in contact with the energized circuit. While you do this, havesomeone else call for help. If you cannot get to the

switchgear quickly, pry the victim from the circuit with something that does not conduct electricity such as dry wood. Do not touch the victim yourself if he or she is still in contact with an electrical circuit!You do not want to be a victim, too!

Do not leave the victim unless there is absolutely no other option. You should staywith the victim while Emergency Medical Services (EMS) is contacted. The callershould come back to you afterwards to verify that the call was made. If the victim isnot breathing, does not have a heartbeat, or is badly injured, quick response by a team of emergency medical technicians (EMT’s) or paramedics gives the best chancefor survival.

What Should I Do If a Co-Worker IsShocked or Burned by Electricity?

Learn first aid

First Aid Fact Sheet

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Page 17

Once you know that electrical current is no longer flowing through the victim, call outto the victim to see if he or she is conscious (awake). If the victim is conscious,tell the victim not to move. It is possible for a shock victim to be seriously injured butnot realize it. Quickly examine the victim for signs of majorbleeding. If there is a lot of bleeding, place a cloth (suchas a handkerchief or bandanna) over the wound and applypressure. If the wound is in an arm or leg and keeps bleed-ing a lot, gently elevate the injured area while keepingpressure on the wound. Keep the victim warm and talk tohim or her until help arrives.

If the victim is unconscious, check for signs of breathing. While you do this, move the victim as little as possible. If the victim is not breathing, someone trained in CPR should begin artificial breathing, then check to see if the victim has a pulse.Quick action is essential! To be effective, CPR must be performed within 4 minutes of the shock.

If you are not trained in CPR or first aid, now is the time to get trained—beforeyoufind yourself in this situation! Ask your instructor or supervisor how you can becomecertified in CPR. You also need to knowthe location of (1) electricity shut-offs(“kill switches”), (2) first-aid sup-plies, and (3) a telephone so youcan find them quickly in anemergency.

and CPR now!

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Section 4:Overview of the Safety Model What Must Be Done to Be Safe?Use the three-stage safety model: recognize, evaluate, and controlhazards. To be safe, you must think about your job and plan for hazards. To avoid injury ordeath, you must understandand recognize hazards. Youneed to evaluate the situationyou are in and assess yourrisks. You need to control haz-ards by creating a safe workenvironment, by using safework practices, and by report-ing hazards to a supervisor orteacher.

If you do not recognize, evalu-ate, and control hazards, youmay be injured or killed by theelectricity itself, electricalfires, or falls. If you use thesafety model to recognize, evaluate, and control hazards,you are much safer.

(1) Recognize hazardsThe first part of the safety model is recognizing the hazards aroundyou. Only then can you avoid or control the hazards. It is best to discuss and plan hazard recognition tasks with your co-workers.Sometimes we take risks ourselves, but when we are responsible forothers, we are more careful. Sometimes others see hazards that weoverlook. Of course, it is possible to be talked out of our concerns

❚ Use the safety model to recognize,evaluate, and control hazards.

❚ Identify electrical hazards.

❚ Don’t listen to reckless,dangerous people.

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Report hazards to your supervisoror teacher.

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by someone who is reckless or dangerous. Don’t take a chance.Careful planning of safety procedures reduces the risk of injury.Decisions to lock out and tag out circuits and equipment need to bemade during this part of the safety model. Plans for action must bemade now.

(2) Evaluate hazardsWhen evaluating hazards, it is best to identify all possible hazardsfirst, then evaluate the risk of injury from each hazard. Do notassume the risk is low until you evaluate the hazard. It is dangerousto overlook hazards. Job sites are especially dangerous because theyare always changing. Many people are working at different tasks.Job sites are frequently exposed to bad weather. A reasonable placeto work on a bright, sunny day might be very hazardous in the rain.The risks in your work environment need to be evaluated all thetime. Then, whatever hazards are present need to be controlled.

(3) Control hazardsOnce electrical hazards have been recognized and evaluated, theymust be controlled. You control electrical hazards in two main ways:(1) create a safe work environment and (2) use safe work practices.Controlling electrical hazards (as well as other hazards) reduces therisk of injury or death.

OSHA regulations, the NEC, and the NationalElectrical Safety Code (NESC) provide a widerange of safety information. Although these sourcesmay be difficult to read and understand at first, withpractice they can become very useful tools to helpyou recognize unsafe conditions and practices.Knowledge of OSHA standards is an important partof training for electrical apprentices. See theAppendix for a list of relevant standards.

❚ Evaluate your risk.

❚ Take steps to control hazards:Create a safe workplace.Work safely.

Section 4 Page 19

S A F E T Y M O D E L

Always lock out and tag out circuits.

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OV E RV I E W O F T H E

Use the safety model to recognize , evaluate , and control workplace hazards like those in this picture.

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Summary of Section 4 The three stages of the safety model are• • •

Stage 1— Recognizehazards

Stage 2— Evaluate hazards

Stage 3—Control hazards

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S A F E T Y M O D E L

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Section 5Safety Model Stage 1—Recognizing HazardsHow Do You Recognize Hazards?The first step toward protecting yourself is recognizing the manyhazards you face on the job. To do this, you must know which situa-tions can place you in danger. Knowing where to look helps you torecognize hazards.

❑ Inadequate wiring is dangerous.

❑ Exposed electrical parts are dangerous.

❑ Overhead powerlines are dangerous.

❑ Wires with bad insulation can give you a shock.

❑ Electrical systems and tools that are not grounded or double-insu-lated are dangerous.

❑ Overloaded circuits are dangerous.

❑ Damaged power tools and equipment are electrical hazards.

❑ Using the wrong PPE is dangerous.

❑ Using the wrong tool is dangerous.

❑ Some on-site chemicals are harmful.

❑ Defective ladders and scaffolding are dangerous.

❑ Ladders that conduct electricity are dangerous.

❑ Electrical hazards can be made worse if the worker, location, orequipment is wet.

❚ Workers face many hazards on the job.

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S A F E T Y M O D E L S TAG E 1

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Section 5 Page 23

— R E C O G N I Z I N G H A Z A R D S

Worker was electrocuted while removingenergized fish tape.

Fish tape.

A n electrician was removing a metal fish tape from a hole at the base of a metal light pole. (Afish tape is used to pull wire through a conduit run.) The fish tape became energized, electro-cuting him. As a result of its inspection, OSHA issued a citation for three serious violations of

the agency’s construction standards.

If the following OSHA requirements had been followed, this death could have beenprevented.

• De-energize all circuits before beginning work.

• Always lock out and tag out de-energized equipment.

• Companies must train workers to recognize and avoid unsafe conditions associ-ated with their work.

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Inadequate wiring hazardsAn electrical hazard exists when the wire is too small a gauge for thecurrent it will carry. Normally, the circuit breaker in a circuit ismatched to the wire size. However, in older wiring, branch lines topermanent ceiling light fixtures could be wired with a smaller gaugethan the supply cable. Let’s say a light fixture is replaced with anotherdevice that uses more current. The current capacity (ampacity) of thebranch wire could be exceeded. When a wire is too small for the cur-rent it is supposed to carry, the wire will heat up. The heated wirecould cause a fire.

When you use an extension cord, the size of the wire you are plac-ing into the circuit may be too small for the equipment. The circuitbreaker could be the right size for the circuit but not right for thesmaller-gauge extension cord. A tool plugged into the extension cordmay use more current than the cord can handle without tripping thecircuit breaker. The wire will overheat and could cause a fire.

The kind of metal used as a conductor can cause an electricalhazard. Special care needs to be taken with aluminum wire.Since it is more brittle than copper, aluminum wire can crackand break more easily.Connections with aluminumwire can become loose andoxidize if not made properly,creating heat or arcing. Youneed to recognize that inade-quate wiring is a hazard.

Exposed electricalparts hazardsElectrical hazards exist whenwires or other electrical partsare exposed. Wires and partscan be exposed if a cover isremoved from a wiring orbreaker box. The overheadwires coming into a homemay be exposed. Electrical

❚ wire gauge— wire size or diameter(technically, the cross-sectional area)

❚ ampacity— the maximum amount of current a wire can carry safelywithout overheating

❚ Overloaded wires get hot!

❚ Incorrect wiring practices can cause fires!

❚ If you touch live electrical parts,you will be shocked.

Page 24 Section 5


This hand-held sander hasexposed wires and should notbe used.

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terminals in motors, appliances, and electronic equipment may beexposed. Older equipment may have exposed electrical parts. If youcontact exposed live electrical parts, you will be shocked. You needto recognize that an exposed electrical component is a hazard.

Overhead powerline hazardsMost people do not realize that overhead powerlines are usually notinsulated. More than half of all electrocutions are caused by directworker contact with energized powerlines. Powerline workers mustbe especially aware of the dangers of overhead lines. In the past,80% of all lineman deaths were caused by contacting a live wirewith a bare hand. Due to such incidents, all linemen now wear spe-cial rubber gloves that protect them up to 34,500 volts. Today, mostelectrocutions involving overhead powerlines are caused by failureto maintain proper work distances.

❚ Overhead powerlines kill manyworkers!

Section 5 Page 25


Watch out for exposed electrical wires around electronic equipment.

Electrical line workers need special trainingand equipment to work safely.

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Shocks and electrocutions occur where physical barriers are not in place to preventcontact with the wires. When dump trucks,cranes, work platforms, or other conductivematerials (such as pipes and ladders) contactoverhead wires, the equipment operator orother workers can be killed. If you do notmaintain required clearance distances frompowerlines, you can be shocked and killed.(The minimum distance for voltages up to50kV is 10 feet. For voltages over 50kV, theminimum distance is 10 feet plus 4 inchesfor every 10 kV over 50kV.) Never storematerials and equipment under or near over-head powerlines. You need to recognize thatoverhead powerlines are a hazard.

Defective insulation hazardsInsulation that is defective or inadequate is an electrical hazard. Usually, a plastic or rubber covering insulates wires.Insulation prevents conductors from coming in contact with eachother. Insulation also prevents conductors from coming in contactwith people.

❚ insulation— material that does notconduct electricity easily

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Operating a crane near overhead wires is very hazardous.

Five workers were constructing a chain-link fence in front of ahouse, directly below a 7,200-volt energized powerline. As theyprepared to install 21-foot sections of metal top rail on the

fence, one of the workers picked up a section of rail and held it upvertically. The rail contacted the 7,200-volt line, and the worker waselectrocuted. Following inspection, OSHA determined that theemployee who was killed had never received any safety trainingfrom his employer and no specific instruction on how to avoid thehazards associated with overhead powerlines.

In this case, the company failed to obey these regulations:

• Employers must train their workers to recognize and avoid unsafeconditions on the job.

• Employers must not allow their workers to work near any part ofan electrical circuit UNLESS the circuit is de-energized (shut off)and grounded, or guarded in such a way that it cannot be con-tacted.

• Ground-fault protection must be provided at construction sites toguard against electrical shock.

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Extension cords may have damaged insulation. Sometimes the insu-lation inside an electrical tool or appliance is damaged. When insula-

tion is damaged, exposed metalparts may become energized ifa live wire inside touches them.Electric hand tools that are old,damaged, or misused may havedamaged insulation inside. Ifyou touch damaged power toolsor other equipment, you willreceive a shock. You are morelikely to receive a shock if thetool is not grounded or double-insulated. (Double-insulatedtools have two insulation barri-ers and no exposed metalparts.) You need to recognizethat defective insulation is ahazard.

Improper grounding hazards When an electrical system is not grounded properly, a hazard exists.The most common OSHA electrical violation is improper groundingof equipment and circuitry. The metal parts of an electrical wiringsystem that we touch (switch plates, ceiling light fixtures, conduit,etc.) should be grounded and at 0 volts. If the system is not groundedproperly, these parts may become energized. Metal parts of motors,appliances, or electronics that are plugged into improperly groundedcircuits may be energized. When a circuit is not grounded properly, ahazard exists because unwanted voltage cannot be safely eliminated.If there is no safe path to ground for fault currents, exposed metalparts in damaged appliances can become energized.

Extension cords may not provide a continuous path to groundbecause of a broken ground wire or plug. If you contact a defective

❚ If you touch a damaged live powertool, you will be shocked!

❚ A damaged live power tool that isnot grounded or double-insulatedis very dangerous!

❚ fault current— any current that is notin its intended path

❚ ground potential— the voltage agrounded part should have;0 volts relative to ground

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This extension cord isdamaged and should not be used.

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electrical device that is not grounded (or grounded improperly), youwill be shocked. You need to recognize that an improperly groundedelectrical system is a hazard.

Electrical systems are often grounded to metal water pipes that serveas a continuous path to ground. If plumbing is used as a path to groundfor fault current, all pipes must be made of conductive material (a typeof metal). Many electrocutions and fires occur because (during renova-tion or repair) parts of metal plumbing are replaced with plastic pipe,which does not conduct electricity. In these cases, the path to groundis interrupted by nonconductive material.

A ground fault circuit interrupter, or GFCI , is an inexpensive life-saver. GFCI’s detect any difference in current between the two circuitwires (the black wires and white wires). This differ-ence in current could happen when electricalequipment is not working correctly, causing leakage current. If leakage current (a ground fault) is detected in aGFCI-protected circuit, the GFCI switchesoff the current in the circuit, protecting youfrom a dangerous shock. GFCI’s are set at about5 mA and are designed to protect workers fromelectrocution. GFCI’s are able to detect the loss ofcurrent resulting from leakage through a person who is beginning tobe shocked. If this situation occurs, the GFCI switches off the currentin the circuit. GFCI’s are different from circuit breakers because theydetect leakage currents rather than overloads.

Circuits with missing, damaged, or improperly wired GFCI’s mayallow you to be shocked. You need to recognize that a circuitimproperly protected by a GFCI is a hazard.

Overload hazardsOverloads in an electrical system arehazardous because they can produce heator arcing. Wires and other componentsin an electrical system or circuit have amaximum amount of current they cancarry safely. If too many devices areplugged into a circuit, the electrical cur-rent will heat the wires to a very hightemperature. If any one tool uses toomuch current, the wires will heat up.

❚ If you touch a defective live component that is not grounded,you will be shocked.

❚ GFCI—ground fault circuit interrupter—a device that detectscurrent leakage from a circuit toground and shuts the current off

❚ leakage current— current that doesnot return through the intended pathbut instead "leaks” to ground

❚ ground fault— a loss of current froma circuit to a ground connection

❚ overload— too much current in a circuit

❚ An overload can lead to a fire orelectrical shock.

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GFCI receptacle.

Overloads are a major cause of fires.

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The temperature of the wires can be high enough to cause a fire. Iftheir insulation melts, arcing may occur. Arcing can cause a fire inthe area where the overload exists, even inside a wall.

In order to prevent too much current in a circuit, a circuit breaker orfuse is placed in the circuit. If there is too much current in the cir-cuit, the breaker “trips” and opens like a switch. If an overloadedcircuit is equipped with a fuse, an internal part of the fuse melts,opening the circuit. Both breakers and fuses do the same thing: openthe circuit to shut off the electrical current.

If the breakers or fuses are too big for the wires they are supposed toprotect, an overload in the circuit will not be detected and the cur-rent will not be shut off. Overloading leads to overheating of circuitcomponents (including wires) and may cause a fire. You need to recognize that a circuit with improper overcurrent protectiondevices—or one with no overcurrent protection devices at all—is a hazard.

Overcurrent protection devices are built into the wiring of someelectric motors, tools, and electronic devices. For example, if a tooldraws too much current or if it overheats, the current will be shut offfrom within the device itself. Damaged tools can overheat and causea fire. You need to recognize that a damaged tool is a hazard.

Wet conditions hazardsWorking in wet conditions is hazardous because you may become aneasy path for electrical current. If you touch a live wire or otherelectrical component—and you are well-grounded because you arestanding in even a small puddle of water—you will receive a shock.

❚ circuit breaker— an overcurrent protection device that automaticallyshuts off the current in a circuit if anoverload occurs

❚ trip— the automatic opening (turning off) of a circuit by a GFCI orcircuit breaker

❚ fuse— an overcurrent protectiondevice that has an internal part thatmelts and shuts off the current in acircuit if there is an overload

❚ Circuit breakers and fuses that are too big for the circuit are dangerous.

❚ Circuits without circuit breakers orfuses are dangerous.

❚ Damaged power tools can causeoverloads.

❚ Wet conditions are dangerous.

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Damaged equipment can overheat andcause a fire.

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Damaged insulation, equipment, or tools can expose you to liveelectrical parts. A damaged tool may not be grounded properly, sothe housing of the tool may be energized, causing you to receive ashock. Improperly grounded metal switch plates and ceiling lightsare especially hazardous in wet conditions. If you touch a live elec-trical component with an uninsulated hand tool, you are more likelyto receive a shock when standing in water.

But remember: you don’t have to be standing in water to be electro-cuted. Wet clothing, high humidity, and perspiration also increaseyour chances of being electrocuted.You need to recognize that allwet conditions are hazards.

Additional hazardsIn addition to electrical hazards, other types of hazards are present atjob sites. Remember that all of these hazards can be controlled.

❑ There may be chemical hazards. Solvents and other substancesmay be poisonous or cause disease.

❑ Frequent overhead work can cause tendinitis (inflammation) inyour shoulders.

❚ An electrical circuit in a dampplace without a GFCI is dangerous!A GFCI reduces the danger.

❚ There are non-electrical hazards atjob sites, too.

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Overhead work can causelong-term shoulder pain.

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❑ Intensive use of hand tools that involve force or twisting cancause tendinitis of the hands, wrists, or elbows. Use of hand tools can also cause carpal tunnel syndrome, which results whennerves in the wrist are damaged by swelling tendons or contract-ing muscles.

❚PPE—personal protectiveequipment (eye protection,hard hat, special clothing,etc.)

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Frequent use of some hand tools can cause wristproblems such as carpal tunnel syndrome.

A 22-year-old carpenter’s apprentice was killed when he was struck in the head by a nailfired from a powder-actuated nail gun (a device that uses a gun powder cartridge todrive nails into concrete or steel). The nail gun operator fired the gun while attempting

to anchor a plywood concrete form, causing the nail to pass through the hollow form. The nailtraveled 27 feet before striking the victim. The nail gun operator had never received trainingon how to use the tool, and none of the employees in the area was wearing PPE.

In another situation, two workers were building a wall while remodeling a house. One of theworkers was killed when he was struck by a nail fired from a powder-actuated nail gun. Thetool operator who fired the nail was trying to attach a piece of plywood to a wooden stud. Butthe nail shot though the plywood and stud, striking the victim.

Below are some OSHA regulations that should have been followed.

• Employees using powder- or pressure-actuated tools must be trained to use them safely.

• Employees who operate powder- or pressure-actuated tools must be trained to avoid firinginto easily penetrated materials (like plywood).

• In areas where workers could be exposed to flying nails, appropriate PPE must be used.

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❑ Low back pain can result from lifting objects the wrong way orcarrying heavy loads of wire or other material. Back pain canalso occur as a result of injury from poor working surfaces suchas wet or slippery floors. Back pain is common, but it can be dis-abling and can affect young individuals.

❑ Chips and particles flying from tools can injure your eyes. Weareye protection.

❑ Falling objects can hit you. Wear a hard hat.

❑ Sharp tools and power equipment can cause cuts and otherinjuries. If you receive a shock, you may react and be hurt by a tool.

❑ You can be injured or killed by falling from a ladder or scaffold-ing. If you receive a shock—even a mild one—you may loseyour balance and fall. Even without being shocked, you couldfall from a ladder or scaffolding.

❑ You expose yourself to hazards when you do not wear PPE.

All of these situations need to be recognized as hazards.

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Lift with your legs, notyour back!

You need to be especiallycareful when working onscaffolding or ladders.

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Summary of Section 5 You need to be able to recognize that electrical shocks, fires, or fallsresult from these hazards:

Inadequate wiring

Exposed electrical parts

Overhead powerlines

Defective insulation

Improper grounding

Overloaded circuits

Wet conditions

Damaged tools and equipment

Improper PPE

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Section 6 Safety Model Stage 2—Evaluating HazardsHow Do You Evaluate Your Risk?After you recognize a hazard, your next step is to evaluate your riskfrom the hazard. Obviously, exposed wires should be recognized asa hazard. If the exposed wires are 15 feet off the ground, your risk islow. However, if you are going to be working on a roof near thosesame wires, your risk is high. The risk of shock is greater if you willbe carrying metal conduit that could touch the exposed wires. Youmust constantly evaluate your risk.

Combinations of hazards increase your risk. Improper groundingand a damaged tool greatly increase your risk. Wet conditions com-bined with other hazards also increase your risk. You will need tomake decisions about the nature of hazards in order to evaluate yourrisk and do the right thing to remain safe.

There are “clues” that electrical hazards exist. For example, if aGFCI keeps tripping while you are using a power tool, there is aproblem. Don’t keep resetting the GFCI and continue to work. Youmust evaluate the “clue” and decide what action should be taken tocontrol the hazard. There are a number of other conditions that indi-cate a hazard.

❑ Tripped circuit breakers and blown fuses show that too muchcurrent is flowing in a circuit. This condition could be due to sev-eral factors, such as malfunctioning equipment or a short betweenconductors. You need to determine the cause in order to controlthe hazard.

❑ An electrical tool, appliance, wire, or connection that feels warmmay indicate too much current in the circuit or equipment. Youneed to evaluate the situation and determine your risk.

❑ An extension cord that feels warm may indicate too much currentfor the wire size of the cord. You must decide when action needsto be taken.

❚ risk— the chance that injury or death will occur

❚ Make the right decisions.

❚ short— a low-resistance pathbetween a live wire and the ground, or between wires at different voltages (called a fault if the current is unintended)

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S A F E T Y M O D E L S TAG E

Combinations of hazards increase risk.

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Any of these conditions, or“ clues,” tells you somethingimportant: there is a risk of fireand electrical shock. The equip-ment or tools involved must beavoided. You will frequently becaught in situations where youneed to decide if these clues arepresent. A maintenance electri-cian, supervisor, or instructorneeds to be called if there aresigns of overload and you are notsure of the degree of risk. Ask forhelp whenever you are not surewhat to do. By asking for help, youwill protect yourself and others.

❑ A cable, fuse box, or junction box that feels warm may indicatetoo much current in the circuits.

❑ A burning odor may indicate overheated insulation.

❑ Worn, frayed, or damaged insulation around any wire or otherconductor is an electrical hazard because the conductors could beexposed. Contact with an exposed wire could cause a shock.Damaged insulation could cause a short, leading to arcing or afire. Inspect all insulation for scrapes and breaks. You need toevaluate the seriousness of any damage you find and decide howto deal with the hazard.

❑ A GFCI that trips indicates there is current leakage from the cir-cuit. First, you must decide the probable cause of the leakage byrecognizing any contributing hazards. Then, you must decidewhat action needs to be taken.

Summary of Section 6 Look for “clues” that hazards are present.

Evaluate the seriousness of hazards.

Decide if you need to take action.

Don’t ignore signs of trouble.

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2 — E VA L UAT I N G H A Z A R D S

An 18-year-old male worker, with 15 months of experience at a fast food restaurant, was plugging a toast-er into a floor outlet when he received a shock. Since the restaurant was closed for the night, the floorhad been mopped about 10 minutes before the incident. The restaurant manager and another employee

heard the victim scream and investigated. The victim was found with one hand on the plug and the other handgrasping the metal receptacle box. His face was pressed against the top of the outlet. An employee tried to takethe victim’s pulse but was shocked. The manager could not locate the correct breaker for the circuit. He thencalled the emergency squad, returned to the breaker box, and found the correct breaker. By the time the circuitwas opened (turned off), the victim had been exposed to the current for 3 to 8 minutes. The employee checkedthe victim’s pulse again and found that it was very rapid.

The manager and the employee left the victim to unlock the front door and place another call for help. Anotheremployee arrived at the restaurant and found that the victim no longer had a pulse. The employee beganadministering CPR, which was continued by the rescue squad for 90 minutes. The victim was dead on arrivalat a local hospital.

Later, two electricians evaluated the circuit and found no serious problems. An investigation showed that thevictim’s hand slipped forward when he was plugging in the toaster. His index finger made contact with anenergized prong in the plug. His other hand was on the metal receptacle box, which was grounded. Currententered his body through his index finger, flowed across his chest, and exited through the other hand, whichwas in contact with the grounded receptacle.

To prevent death or injury, you must recognize hazards and take the right action.

• If the circuit had been equipped with a GFCI, the current would have been shut off before injury occurred.

• The recent mopping increased the risk of electrocution. Never work in wet or damp areas!

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Section 7 Safety Model Stage 3—Controlling Hazards:Safe Work EnvironmentHow Do You Control Hazards? In order to control hazards, you must first create a safe work envi-ronment, then work in a safe manner. Generally, it is best to removethe hazards altogether and create an environment that is truly safe.When OSHA regulations and the NEC are followed, safe work envi-ronments are created.

But, you never know when materials or equipment might fail.Prepare yourself for the unexpected by using safe work practices.Use as many safeguards as possible. If one fails, another may pro-tect you from injury or death.

How Do You Create a Safe Work Environment?A safe work environment is created by controlling contact with elec-trical voltages and the currents they can cause. Electrical currentsneed to be controlled so they do not pass through the body. In addi-tion to preventing shocks, a safe work environment reduces thechance of fires, burns, and falls.

You need to guard against contact with electrical voltages and con-trol electrical currents in order to create a safe work environment.Make your environment safer by doing the following:

❑ Treat all conductors—even “de-energized” ones—as if they areenergized until they are locked out and tagged.

❑ Lock out and tag out circuits and machines.

❑ Prevent overloaded wiring by using the right size and type of wire.

❑ Prevent exposure to live electrical parts by isolating them.

❑ Prevent exposure to live wires and parts by using insulation.

❑ Prevent shocking currents from electrical systems and tools bygrounding them.

❑ Prevent shocking currents by using GFCI’s.

❑ Prevent too much current in circuits by using overcurrent protection devices.

❚ Guard against contact with electrical voltages and controlelectrical currents to create a safe work environment.

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S A F E T Y M O D E L S TAG E 3 — C O N T R O L L I N G

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Lock out and tag out circuits and equipmentCreate a safe work environment by locking out and tagging out circuits and machines. Before working on a circuit, you must turn off the power supply. Once the circuit has been shut off and de-energized, lock out the switchgear to the circuit so the powercannot be turned back on inadvertently. Then, tag out the circuitwith an easy-to-see sign or label that lets everyone know that you areworking on the circuit. If you are working on or near machinery, you must lock out and tag out the machinery to prevent startup.Before you begin work, you must test the circuit to make sure it is de-energized.

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H A Z A R D S : S A F E W O R K E N V I R O N M E N T

At about 1:45 a.m., two journeyman electricians began replacing bulbs and making repairs on lightfixtures in a spray paint booth at an automobile assembly plant. The job required the two electricians to climb on top of the booth and work from above. The top of the booth was filled with

pipes and ducts that restricted visibility and movement. Flashlights were required.

The electricians started at opposite ends of the booth. One electrician saw a flash of light, but continuedto work for about 5 minutes, then climbed down for some wire. While cutting the wire, he smelled a burn-ing odor and called to the other electrician. When no one answered, he climbed back on top of the booth.He found his co-worker in contact with a single-strand wire from one of the lights. Needle-nose wire strip-pers were stuck in the left side of the victim’s chest. Apparently, he had been stripping insulation from animproperly grounded 530-volt, single-strand wire when he contacted it with the stripper. In this case, theelectricians knew they were working on energized circuits. The breakers in the booth’s control panel werenot labeled and the lock used for lock-out/tag-out was broken. The surviving electrician stated that locat-ing the means to de-energize a circuit often takes more time than the actual job.

The electrician would be alive today if the following rules had been observed.

• Always shut off circuits—then test to confirm that they are de-energized—before starting a job.

• Switchgear that shuts off a circuit must be clearly labeled and easy to access.

• Lock-out/tag-out materials must always be provided, and lock-out/tag-out procedures must always be followed.

Always test a circuit to make sure it isde-energized before working on it.

Lock-out/tag-out saves lives.

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Lock-Out/Tag-Out Checklist

Lock-out/tag-out is an essential safety procedurethat protects workers from injury while working onor near electrical circuits and equipment. Lock-outinvolves applying a physical lock to the powersource(s) of circuits and equipment after they havebeen shut off and de-energized. The source is thentagged out with an easy-to-read tag that alerts otherworkers in the area that a lock has been applied.

I n addition to protecting workers from electri-cal hazards, lock-out/tag-out prevents contactwith operating equipment parts: blades, gears,

shafts, presses, etc.

Also, lock-out/tag-out prevents the unexpectedrelease of hazardous gasses, fluids, or solid matterin areas where workers are present.

An employee was cutting into a metal pipe using ablowtorch. Diesel fuel was mistakenly dischargedinto the line and was ignited by his torch. Theworker burned to death at the scene.

All valves along the line should have been lockedout, blanked out, and tagged out to prevent therelease of fuel. Blanking is the process of insertinga metal disk into the space between two pipeflanges. The disk, or blank, is then bolted in placeto prevent passage of liquids or gasses throughthe pipe.

A worker was replacing a V-belt on a dust collectorblower. Before beginning work, he shut down theunit at the local switch. However, an operator in thecontrol room restarted the unit using a remoteswitch. The worker’s hand was caught between thepulley and belts of the blower, resulting in cuts anda fractured finger.

When performing lock-out/tag-out on machinery,you must always lock out and tag out ALL energysources leading to the machinery.

When performing lock-out/tag-out on circuitsand equipment, you can use the checklist below.✔ Identify all sources of electrical energy for the

equipment or circuits in question.✔ Disable backup energy sources such as gener-

ators and batteries. ✔ Identify all shut-offs for each energy source.✔ Notify all personnel that equipment and

circuitry must be shut off, locked out, andtagged out. (Simply turning a switch off isNOT enough.)

✔ Shut off energy sources and lock switchgearin the OFF position. Each worker shouldapply his or her individual lock. Do not giveyour key to anyone.

✔ Test equipment and circuitry to make surethey are de-energized. This must be done by aqualified person.*

✔ Deplete stored energy by bleeding, blocking,grounding, etc.

✔ Apply a tag to alert other workers that anenergy source or piece of equipment has beenlocked out.

✔ Make sure everyone is safe and accounted forbefore equipment and circuits are unlockedand turned back on. Note that only a qualifiedperson may determine when it is safe to re-energize circuits.

*OSHA defines a “qualified person” as someone who hasreceived mandated training on the hazards and on the construction and operation of equipment involved in a task.

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Control inadequate wiring hazards Electrical hazards result from using the wrong size or type of wire.You must control such hazards to create a safe work environment.You must choose the right size wire for the amount of currentexpected in a circuit. The wire must be able to handle the currentsafely. The wire’s insulation must be appropriate for the voltage andtough enough for the environment. Connections need to be reliableand protected.

❚ Use the right size and type ofwire.

❚ AWG—American Wire Gauge—a measure of wire size

Section 7 Page 39


14 AWG 12 AWG 12 AWG 10 AWG 8 AWG 6 AWG 2 AWG 1/0 AWG(stranded) (solid)

20 amps 25 amps 30 amps 40 amps 55 amps 95 amps 125 amps

Wires come in different sizes. The maximum current each size can conduct safely is shown.

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Control hazards of fixed wiringThe wiring methods and size of conductors used in a system dependon several factors:

❑ Intended use of the circuit system

❑ Building materials

❑ Size and distribution of electrical load

❑ Location of equipment (such as underground burial)

❑ Environmental conditions (such as dampness)

❑ Presence of corrosives

❑ Temperature extremes

Fixed, permanent wiring is better than extension cords, which can bemisused and damaged more easily. NEC requirements for fixedwiring should always be followed. A variety of materials can beused in wiring applications, including nonmetallic sheathed cable(Romex®), armored cable, and metal and plastic conduit. Thechoice of wiring material depends on the wiring environment andthe need to support and protect wires.

Aluminum wire and connections should be handled with specialcare. Connections made with aluminum wire can loosen due to heat expansion and oxidize if they are not made properly. Loose or oxidized connections can create heat or arcing. Special clampsand terminals are necessary to make proper connections using aluminum wire. Antioxidant paste can be applied to connections toprevent oxidation.

Control hazards of flexible wiringUse flexible wiring properly

Electrical cords supplement fixed wiring by providing the flexibilityrequired for maintenance, portability, isolation from vibration, andemergency and temporary power needs.

❚ fixed wiring— the permanent wiring installed in homes and other buildings

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Nonmetalic sheathing helps protectwires from damage.

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Flexible wiring can be used for extension cords or power supplycords. Power supply cords can be removable or permanentlyattached to the appliance.

DO NOT use flexible wiring in situations where frequent inspectionwould be difficult, where damage would be likely, or where long-term electrical supply is needed. Flexible cords cannot be used as a substitute for the fixed wiring of a structure. Flexible cords mustnot be . . .

❑ run through holes in walls, ceilings, or floors;

❑ run through doorways, windows, or similar openings (unlessphysically protected);

❑ attached to building surfaces (except with a tension take-updevice within 6 feet of the supply end);

❑ hidden in walls, ceilings, or floors; or

❑ hidden in conduit or other raceways.

❚ flexible wiring— cables with insulated and stranded wire thatbends easily

❚ Don’t use flexible wiring where itmay get damaged.

Section 7 Page 41


A 29-year-old male welder was assigned to work on an outdoor concrete platform attached to themain factory building. He wheeled a portable arc welder onto the platform. Since there was not anelectrical outlet nearby, he used an extension cord to plug in the welder. The male end of the cord

had four prongs, and the female end was spring-loaded. The worker plugged the male end of the cord intothe outlet. He then plugged the portable welder’s power cord into the female end of the extension cord. Atthat instant, the metal case around the power cord plug became energized, electrocuting the worker.

An investigation showed that the female end of the extension cord was broken. The spring, cover plate,and part of the casing were missing from the face of the female connector. Also, the grounding prong onthe welder’s power cord plug was so severely bent that it slipped outside of the connection. Therefore, thearc welder was not grounded. Normally, it would have been impossible to insert the plug incorrectly. But,since the cord’s female end was damaged, the “bad” connection was able to occur.

Do not let this happen to you. Use these safe practices:

• Thoroughly inspect all electrical equipment before beginning work.

• Do not use extension cords as a substitute for fixed wiring. In this case, a weatherproof receptacleshould have been installed on the platform.

• Use connectors that are designed to stand up to the abuse of the job. Connectors designed for light-duty use should not be used in an industrial environment.

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Use the right extension cord

The size of wire in an extension cord must be compatible with theamount of current the cord will be expected to carry. The amount ofcurrent depends on the equipment plugged into the extension cord.Current ratings (how much current a device needs to operate) areoften printed on the nameplate. If a power rating is given, it is neces-sary to divide the power rating in watts by the voltage to find the cur-rent rating. For example, a 1,000-watt heater plugged into a 120-voltcircuit will need almost 10 amps of current. Let’s look at anotherexample: A 1-horsepower electric motor uses electrical energy at therate of almost 750 watts, so it will need a minimum of about 7 ampsof current on a 120-volt circuit. But, electric motors need additionalcurrent as they startup or if they stall, requiring up to 200% of thenameplate current rating. Therefore, the motor would need 14 amps.

Add to find the total current needed to operate all the appliancessupplied by the cord. Choose a wire size that can handle the totalcurrent.

American Wire Gauge (AWG)

Remember: The larger the gauge number, the smaller the wire!

The length of the extension cord also needs to be considered whenselecting the wire size. Voltage drops over the length of a cord. If acord is too long, the voltage drop can be enough to damage equip-ment. Many electric motors only operate safely in a narrow range ofvoltages and will not work properly at voltages different than thevoltage listed on the nameplate. Even though light bulbs operate(somewhat dimmer) at lowered voltages, do not assume electricmotors will work correctly at less-than-required voltages. Also,when electric motors start or operate under load, they require morecurrent. The larger the size of the wire, the longer a cord can bewithout causing a voltage drop that could damage tools and equipment.

Wire size

#10 AWG #12 AWG #14 AWG #16 AWG

Handles up to

30 amps25 amps 18 amps 13 amps

❚ power— the amount of energy usedin a second, measured in watts

❚ 1 horsepower = 746 watts.

❚ Do not use extension cords thatare too long for the size of wire.

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The grounding path for extension cords must be kept intact to keepyou safe. A typical extension cord grounding system has four components:

❑ a third wire in the cord, called a ground wire;

❑ a three-prong plug with a grounding prong on oneend of the cord;

❑ a three-wire, grounding-type receptacle at the other endof the cord; and

❑ a properly grounded outlet.

Control hazards of exposed live electricalparts: isolate energized components Electrical hazards exist when wires or other electrical parts areexposed. These hazards need to be controlled to create a safe workenvironment. Isolation of energized electrical parts makes them inac-cessible unless tools and special effort are used. Isolation can beaccomplished by placing the energized parts at least 8 feet high andout of reach, or by guarding. Guarding is a type of isolation that usesvarious structures—like cabinets, boxes, screens, barriers, covers, andpartitions—to close-off live electrical parts.

❚ Make sure the path to ground iscontinuous.

❚ guarding— a covering or barrier thatseparates you from live electrical parts

Section 7 Page 43


Outlets must begrounded properly.

This exposed electrical equipment is guardedby an 8-foot fence. Use covers to prevent

accidental contact withelectrical circuits.

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Take the following precautions to prevent injuries from contact withlive parts:

❑ Immediately report exposed live parts to a supervisor or teacher.As a student, you should never attempt to correct the conditionyourself without supervision.

❑ Provide guards or barriers if live parts cannot be enclosed completely.

❑ Use covers, screens, or partitions for guarding that require toolsto remove them.

❑ Replace covers that have been removed from panels, motors, orfuse boxes.

❑ Even when live parts are elevated to the required height (8 feet),care should be taken when using objects (like metal rods orpipes) that can contact these parts.

❑ Close unused conduit openings in boxes so that foreign objects(pencils, metal chips, conductive debris, etc.) cannot get insideand damage the circuit.

Control hazards of exposure to live electrical wires: use proper insulation Insulation is made of material that does not conduct electricity (usually plastic, rubber,or fiber). Insulation covers wires and prevents

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A 20-year-old male laborer was carrying a 20-foot piece of iron from a welding shop to an outsidestorage rack. As he was turning a corner near a bank of electrical transformers, the top end of thepiece of iron struck an uninsulated supply wire at the top of a transformer. Although the trans-

formers were surrounded by a 6-foot fence, they were about 3 feet taller than the fence enclosure. Eachtransformer carried 4,160 volts.

When the iron hit the supply wire, the laborer was electrocuted. A forklift operator heard the iron drop tothe ground at about 8:46 a.m. and found the victim 5 minutes later. He was pronounced dead on arrivalat a local hospital.

• According to OSHA, the enclosure around the transformers was too short. The fence should have beenat least 8 feet tall.

• The company in this case did not offer any formal safety training to its workers. All employers shoulddevelop safety and health training programs so their employees know how to recognize and avoid life-threatening hazards.

This cover cannot be removed without special tools.

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conductors from coming in contact with each other or any other conductor. If conductors are allowed to make contact, a short circuitis created. In a short circuit, current passes through the shortingmaterial without passing through a load in the circuit, and the wirebecomes overheated. Insulation keeps wires and other conductorsfrom touching, which prevents electrical short circuits. Insulationprevents live wires from touching people and animals, thus protect-ing them from electrical shock.

Insulation helps protect wires from physical damage and conditionsin the environment. Insulation is used on almost all wires, exceptsome ground wires and some high-voltage transmission lines.Insulation is used internally in tools, switches, plugs, and other elec-trical and electronic devices.

Special insulation is used on wires and cables that are used in harshenvironments. Wires and cables that are buried in soil must have anouter covering of insulation that is flame-retardant and resistant tomoisture, fungus, and corrosion.

In all situations, you must be careful not to damage insulation whileinstalling it. Do not allow staples or other supports to damage theinsulation. Bends in a cable must have an inside radius of at least

❚ Make sure insulation is the righttype and in good condition.

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A 29-year-old male maintenance worker was found at 3:45 a.m. lying on his back and convulsing.Beside him were an overturned cart and an electric welding machine, both lying in a pool of wateron the concrete floor. Arcing was visible between the welding machine and the floor. The worker

was transported to the closest hospital, where he was pronounced dead.

An examination of the welding machine showed that there were exposed conductors in the machine’scables. There were numerous cuts and scrapes in the cables’ insulation. On other parts of the machine,insulation was damaged or missing. Also, the machine did not have a ground connection.

Investigators concluded that the maintenance worker was electrocuted when he tried to turn off the weld-ing machine, which was sitting on the cart. The metal frame of the machine had become energized due tothe damaged insulation. When he touched the energized frame, he completed the conducting path toground. The current traveled through his body to ground. Since he was probably standing in water, the riskof a ground fault was even greater.

You must take steps to decrease such hazards in your workplace:

• Ground circuits and equipment.

• Keep all equipment in good operating condition with a preventive maintenance program.

• Never use electrical equipment or work on circuits in wet areas. If you find water or dampness, notifyyour supervisor immediately.

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5 times the diameter of the cable so that insulation at a bend is notdamaged. Extension cords come with insulation in a variety of typesand colors. The insulation of extension cords is especially important.Since extension cords often receive rough handling, the insulationcan be damaged. Extension cords might be used in wet places, soadequate insulation is necessary to prevent shocks. Because exten-sion cords are often used near combustible materials (such as woodshavings and sawdust) a short in an extension cord could easilycause arcing and a fire.

Insulation on individual wires is often color-coded. In general, insu-lated wires used as equipment grounding conductors are either con-tinuous green or green with yellow stripes. The grounded conductorsthat complete a circuit are generally covered with continuous whiteor gray insulation. The ungrounded conductors, or “hot” wires, maybe any color other than green, white, or gray. They are usually blackor red.

Conductors and cables must be marked by the manufacturer to showthe following:

❑ maximum voltage capacity,

❑ AWG size,

❑ insulation-type letter, and

❑ the manufacturer’s name or trademark.

Control hazards of shocking currentsGround circuits and equipment

When an electrical system is not grounded properly, a hazard exists.This is because the parts of an electrical wiring system that a personnormally touches may be energized, or live, relative to ground. Partslike switch plates, wiring boxes, conduit, cabinets, and lights need tobe at 0 volts relative to ground. If the system is grounded improper-ly, these parts may be energized. The metal housings of equipmentplugged into an outlet need to be grounded through the plug.

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Ground electricaldevices.

Arc-fault circuitbreaker.

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Grounding is connecting an electrical system to the earth with a wire.Excess or stray current travels through this wire to a groundingdevice (commonly called a “ground”) deep in the earth. Groundingprevents unwanted voltage on electrical components. Metal plumbingis often used as a ground. When plumbing is used as a groundingconductor, it must also be connected to a grounding device such as aconductive rod. (Rods used for grounding must be driven at least 8 feet into the earth.) Sometimes an electrical system will receive ahigher voltage than it is designed to handle. These high voltages maycome from a lightning strike, line surge, or contact with a higher-voltage line. Sometimes a defect occurs in a device that allowsexposed metal parts to become energized. Grounding will help protect the person working on a system, the system itself, and othersusing tools or operating equipment connected to the system. Theextra current produced by the excess voltage travels relatively safelyto the earth.

Grounding creates a path for currents produced by unintended voltages on exposed parts. These currents follow the grounding path,rather than passing through the body of someone who touches theenergized equipment. However, if a grounding rod takes a direct hitfrom a lightning strike and is buried in sandy soil, the rod should beexamined to make sure it will still function properly. The heat froma lightning strike can cause the sand to turn into glass, which is aninsulator. A grounding rod must be in contact with damp soil to beeffective.

Leakage current occurs when an electrical current escapes from itsintended path. Leakages are sometimes low-current faults that canoccur in all electrical equipment because of dirt, wear, damage, ormoisture. A good grounding system should be able to carry off thisleakage current. A ground fault occurs when current passes throughthe housing of an electrical device to ground. Proper grounding pro-tects against ground faults. Ground faults are usually caused by misuse of a tool or damage to its insulation. This damage allows abare conductor to touch metal parts or the tool housing.

When you ground a tool or electrical system, you create a low-resistance path to the earth (known as a ground connection). Whendone properly, this path has sufficient current-carrying capacity toeliminate voltages that may cause a dangerous shock.

Grounding does not guarantee that you will not be shocked, injured,or killed from defective equipment. However, it greatly reduces thepossibility.

Section 7 Page 47


Grounding-typereceptacle.

Grounding rod inthe earth.

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Equipment needs to be grounded under any of these circumstances:

❑ The equipment is within 8 feet vertically and 5 feet horizontallyof the floor or walking surface.

❑ The equipment is within 8 feet vertically and 5 feet horizontallyof grounded metal objects you could touch.

❑ The equipment is located in a wet or damp area and is not isolated.

❑ The equipment is connected to a power supply by cord and plugand is not double-insulated.

Use GFCI’s

The use of GFCI’s has lowered the number of electrocutions dramat-ically. A GFCI is a fast-acting switch that detects any difference incurrent between two circuit conductors. If either conductor comes incontact—either directly or through part of your body—with aground (a situation known as a ground fault), the GFCI opens thecircuit in a fraction of a second. If a current as small as 4 to 6 mAdoes not pass through both wires properly, but instead leaks to theground, the GFCI is tripped. The current is shut off.

There is a more sensitive kind of GFCI called an isolation GFCI. Ifa circuit has an isolation GFCI, the ground fault current passesthrough an electronic sensing circuit in the GFCI. The electronicsensing circuit has enough resistance to limit current to as little as 2 mA, which is too low to cause a dangerous shock.

GFCI’s are usually in the form of a duplex receptacle. They are alsoavailable in portable and plug-in designs and as circuit breakers that protect an entire branch circuit. GFCI’s can operate on bothtwo- and three-wire ground systems. For a GFCI to work properly,the neutral conductor (white wire) must (1) be continuous, (2) havelow resistance, and (3) have sufficient current-carrying capacity.

GFCI’s help protect you from electrical shock by continuously mon-itoring the circuit. However, a GFCI does not protect a person fromline-to-line hazards such as touching two “hot” wires (240 volts) atthe same time or touching a “hot” and neutral wire at the same time.Also be aware that instantaneous currents can be high when a GFCIis tripped. A shock may still be felt. Your reaction to the shock couldcause injury, perhaps from falling.

Test GFCI’s regularly by pressing the “test” button. If the circuitdoes not turn off, the GFCI is faulty and must be replaced.

❚ GFCI’s have their limitations.

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Portable GFCI.

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The NEC requires that GFCI’s be used in these high-risk situations:

❑ Electricity is used near water.

❑ The user of electrical equipment is grounded (by touchinggrounded material).

❑ Circuits are providing power to portable tools or outdoor receptacles.

❑ Temporary wiring or extension cords are used.

Specifically, GFCI’s must be installed in bathrooms, garages, out-door areas, crawl spaces, unfinished basements, kitchens, and nearwet bars.

Bond components to assure grounding path

In order to assure a continuous, reliable electrical path to ground, abonding jumper wire is used to make sure electrical parts are con-nected. Some physical connections, like metal conduit coming into a

❚ Use GFCI’s to help protect peoplein damp areas.

❚ bonding— joining electrical parts toassure a conductive path

Section 7 Page 49


A female assistant manager of a swim club was instructed to add a certain chemical to the pool. Shewent down into the pump room, barefoot. The room was below ground level, and the floor was covered with water. She filled a plastic drum with 35-40 gallons of water, then plugged a mixing

motor into a 120-volt wall outlet and turned on the motor. The motor would be used to mix the water andthe chemical, then the solution would be added to the pool. While adding the chemical to the water in thedrum, she contacted the mixing motor with her left hand. Apparently, the motor had developed a groundfault. Because of the ground fault, the motor was energized, and she was electrocuted. A co-worker foundthe victim slumped over the drum with her face submerged in water. The co-worker tried to move the victim but was shocked. The assistant manager was dead on arrival at a local hospital.

An investigation showed that the mixing motor was in poor condition. The grounding pin had beenremoved from the male end of the power cord, resulting in a faulty ground. The circuit was equipped witha GFCI, but it was not installed properly. A properly wired and functioning GFCI could have sensed theground fault in the motor and de-energized the circuit.

Take a look at what could have been done to prevent this death.

• The employer should have kept the motor in better condition. Power cords should be inspected regularly, and any missing prongs should be replaced.

• All pool-area electrical circuits should be installed by qualified electricians.

• The victim should have worn insulating boots or shoes since she was handling electrical equipment.

• The employer should have followed the law. The NEC requires that all pool-associated motors have apermanent grounding system. In this case, this regulation was not followed. Also, electrical equipmentis not permitted in areas without proper drainage.

• OSHA requires employers to provide a work environment free of safety and health hazards.

Install bonding jumpersaround nonconductivematerial.

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box, might not make a good electrical connection because of paintor possible corrosion. To make a good electrical connection, a bond-ing jumper needs to be installed.

A metal cold water pipe that is part of a path to ground may needbonding jumpers around plastic antivibration devices, plastic watermeters, or sections of plastic pipe. A bonding jumper is made ofconductive material and is tightly connected to metal pipes withscrews or clamps to bypass the plastic and assure a continuousgrounding path. Bonding jumpers are necessary because plastic doesnot conduct electricity and would interrupt the path to ground.

Additionally, interior metal plumbing must be bonded to the groundfor electrical service equipment in order to keep all grounds at thesame potential (0 volts). Even metal air ducts should be bonded toelectrical service equipment.

Control overload current hazardsWhen a current exceeds the current rating of equipment or wiring, ahazard exists. The wiring in the circuit, equipment, or tool cannothandle the current without heating up or even melting. Not only willthe wiring or tool be damaged, but the high temperature of the con-ductor can also cause a fire. To prevent this from happening, anovercurrent protection device (circuit breaker or fuse) is used in acircuit. These devices open a circuit automatically if they detect cur-rent in excess of the current rating of equipment or wiring. Thisexcess current can be caused by an overload, short circuit, or high-level ground fault.

❚ bonding jumper— the conductor used to connectparts to be bonded

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Use overcurrent protection devices (circuit breakers or fuses) in circuits.

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Overcurrent protection devices are designed to protect equipmentand structures from fire. They do not protect you from electricalshock! Overcurrent protection devices stop the flow of current in acircuit when the amperage is too high for the circuit. A circuit break-er or fuse will not stop the relatively small amount of current thatcan cause injury or death. Death can result from 20 mA (.020 amps)through the chest (see Section 2). A typical residential circuit break-er or fuse will not shut off the circuit until a current of more than 20 amps is reached!

But overcurrent protection devices are not allowed in areas wherethey could be exposed to physical damage or in hazardous environ-ments. Overcurrent protection devices can heat up and occasionallyarc or spark, which could cause a fire or an explosion in certainareas. Hazardous environments are places that contain flammable orexplosive materials such as flammable gasses or vapors (Class IHazardous Environments), finely pulverized flammable dusts (Class II Hazardous Environments), or fibers or metal filings thatcan catch fire easily (Class III Hazardous Environments). Hazardousenvironments may be found in aircraft hangars, gas stations, storageplants for flammable liquids, grain silos, and mills where cottonfibers may be suspended in the air. Special electrical systems arerequired in hazardous environments.

If an overcurrent protection device opens a circuit, there may be aproblem along the circuit. (In the case of circuit breakers, frequenttripping may also indicate that the breaker is defective.) When a cir-cuit breaker trips or a fuse blows, the cause must be found.

A circuit breaker is one kind of overcurrent protection device. It is atype of automatic switch located in a circuit. A circuit breaker tripswhen too much current passes through it. A circuit breaker shouldnot be used regularly to turn power on or off in a circuit, unless thebreaker is designed for this purpose and marked “SWD” (stands for“switching device”).

A fuse is another type of overcurrent protection device. A fuse con-tains a metal conductor that has a relatively low melting point.When too much current passes through the metal in the fuse, it heatsup within a fraction of a second and melts, opening the circuit. Afteran overload is found and corrected, a blown fuse must be replacedwith a new one of appropriate amperage.

❚ Find the cause of an overload.

Section 7 Page 51


Only circuit breakersmarked “SWD” shouldbe used as switches.

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Summary of Section 7Control contact with electrical voltages and control electrical currents to create a safe work environment.

Lock out and tag out circuits and machines.

Prevent overloaded wiring by using the right size and type of wire.

Prevent exposure to live electrical parts by isolating them.

Prevent exposure to live wires and parts by using insulation.

Prevent shocking currents from electrical systems and tools by grounding them.

Prevent shocking currents by using GFCI’s.

Prevent too much current in circuits by using overcurrent protection devices.

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Section 7 Page 53


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Section 8 Safety Model Stage 3—Controlling Hazards:Safe Work Practices How Do You Work Safely?A safe work environment is not enough to control all electrical haz-ards. You must also work safely. Safe work practices help you con-trol your risk of injury or death from workplace hazards. If you areworking on electrical circuits or with electrical tools and equipment,you need to use safe work practices.

Before you begin a task, ask yourself:

❑ What could go wrong?

❑ Do I have the knowledge, tools, and experience to do this worksafely?

All workers should be very familiar with the safety procedures for their jobs. You must know how to use specific controls that helpkeep you safe. You must also use good judgment and commonsense.

Control electrical hazards through safe work practices.

❑ Plan your work and plan for safety.

❑ Avoid wet working conditions and other dangers.

❑ Avoid overhead powerlines.

❑ Use proper wiring and connectors.

❑ Use and maintain tools properly.

❑ Wear correct PPE.

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Plan your work and plan for safetyTake time to plan your work, by yourself and with others. Safetyplanning is an important part of any task. It takes effort to recognize,evaluate, and control hazards. If you are thinking about your worktasks or about what others think of you, it is hard to take the time toplan for safety. But, YOU MUST PLAN .

Planning with others is especially helpful. It allows you to coordi-nate your work and take advantage of what others know about iden-tifying and controlling hazards. The following is a list of somethings to think about as you plan.

❑ Work with a “buddy” —Do not work alone. Both of you should be trained in CPR. Both of you must know what to do in an emergency.

❑ Know how to shut off and de-energize circuits—You must findwhere circuit breakers, fuses, and switches are located. Then, thecircuits that you will be working on (even low-voltage circuits)MUST BE TURNED OFF! Test the circuits before beginningwork to make sure they are completely de-energized.

❚ Plan to be safe.

❚ Don’t work alone.

Section 8 Page 55

H A Z A R D S : S A F E W O R K P R AC T I C E S

A 40-year-old male meter technician had just completed a 7-week basic lineman training course. Heworked as a meter technician during normal working hours and as a lineman during unplanned out-ages. One evening, he was called to repair a residential power outage. By the time he arrived at

the site of the outage, he had already worked 2 hours of overtime and worked 14 straight hours the daybefore. At the site, a tree limb had fallen across an overhead powerline. The neutral wire in the line wassevered, and the two energized 120-volt wires were disconnected. The worker removed the tree limb andclimbed up a power pole to reconnect the three wires. He was wearing insulated gloves, a hard hat, andsafety glasses.

He prepared the wires to be connected. While handling the wires, one of the energized wires caught thecuff of his left glove and pulled the cuff down. The conductor contacted the victim’s forearm near the wrist.He was electrocuted and fell backwards. He was wearing a climbing belt, which left him hanging upsidedown from the pole. Paramedics arrived 5 minutes after the contact.The power company lowered his deadbody 30 minutes later.

Several factors may have contributed to this incident. Below are some ways to eliminate these risk factors.

• Ask for assistance when you are assigned tasks that cannot be safely completed alone. The taskassigned to the victim could not have been done safely by only one person.

• Do not work overtime performing hazardous tasks that are not part of your normal assignments.

• Employees should only be given tasks that they are qualified to perform. All employees below the journeyman level should be supervised.

Test circuits to make sure theyare de-energized.

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❑ Plan to lock out and tag out circuits and equipment—Makecertain all energy sources are locked out and tagged out beforeperforming any work on an electrical circuit or electrical device.Working on energized (“hot”) circuits is one of the most danger-ous things any worker could do. If someone turns on a circuitwithout warning, you can be shocked, burned, or electrocuted.The unexpected starting of electrical equipment can cause severeinjury or death.

Before ANY work is done on a circuit, shut off the circuit, lockout and tag out the circuit at the distribution panel, then test thecircuit to make sure it is de-energized.

Before ANY equipment inspections or repairs—even on so-calledlow-voltage circuits—the current must be turned off at the switchbox, and the switch must be padlocked in the OFF position. Atthe same time, the equipment must be securely tagged to warneveryone that work is being performed. Again, test circuits andequipment to ensure they are de-energized.

No two locks should be alike. Each key should fit only one lock,and only one key should be issued to each worker. If more thanone worker is working on a circuit or repairing a piece of equip-ment, each worker should lock out the switch with his or her ownlock and never permit anyone else to remove it. At all times, youmust be certain that you are not exposing other workers to dan-ger. Workers who perform lock-out/tag-out must be trained andauthorized to repair and maintain electrical equipment. A locked-out switch or feeder panel prevents others from turning on a cir-cuit. The tag informs other workers of your action.

❑ Remove jewelry and metal objects—Remove jewelry and othermetal objects or apparel from your body before beginning work.These things can cause burns if worn near high currents and canget caught as you work.

❑ Plan to avoid falls—Injuries can result from falling off scaffold-ing or ladders. Other workers may also be injured from equip-ment and debris falling from scaffolding and ladders.

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This worker is applying a grouplock-out device. Theequipment cannotbe re-started untilall workers removetheir locks.

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Section 8 Page 57


A worker was attempting to correct an electrical problem involving two non-operational lamps. Heexamined the circuit in the area where he thought the problem was located. He had not shut off thepower at the circuit breaker panel and did not test the wires to see if they were live. He was elec-

trocuted when he grabbed the two live wires with his left hand. He collapsed to the floor and was founddead.

• Employers should not allow work to be done on electrical circuits unless an effective lock-out/tag-outprogram is in place.

• No work should be done on energized electrical circuits. Circuits must be shut off, locked out, andtagged out. Even then, you must test the circuit before beginning work to confirm that it is de-energized (“dead”).

277 VOLT LAMPS

FUSE BOX

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To prevent injury when climbing, follow these procedures:

1. Position the ladder at a safe angle to prevent slipping. The hori-zontal distance from the base of the ladder to the structure shouldbe one-quarter the length of the ladder. If you don’t have a wayto make this measurement, follow the steps below to determine ifthe ladder is positioned at a safe angle.

✔ Put your feet at the base of the ladder and extend your armsstraight out.

✔ If you can touch the closest part of the ladder without bendingyour arms, the ladder is probably at the correct angle.

✔ If you have to bend your arms to touch the closest part of the ladder or if you can’t reach the ladder at all, the ladder is notpositioned at a safe angle.

2. Make sure the base of the ladder has firm support and the groundor floor is level. Be very careful when placing a ladder on wet,icy, or otherwise slippery surfaces. Special blocking may beneeded to prevent slipping in these cases.

3. Follow the manufacturer’srecommendations for proper use.

4. Check the condition of theladder before using it. Jointsmust be tight to preventwobbling or leaning.

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Ladder Safety Fact Sheet

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5. When using a stepladder, make sure it is level and fully open.Always lock the hinges. Do not stand on or above the top step.

6. When using scaffolding, use a ladder to access the tiers. Neverclimb the cross braces.

7. Do not use metal ladders. Instead, use ladders made of fiberglass.(Although wooden ladders are permitted, wood can soak up waterand become conductive.)

8. Beware of overhead powerlines when you work with ladders andscaffolding.

Learn how to use ladders and scaffolding properly.

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❑ Do not do any tasks that you are not trained to do or that youdo not feel comfortable doing!

A crew of 7 workers was painting a 33-foot sign at a shopping mall. The crew used tubular welded frame scaffolding that was 31 feet tall and made up of several tiers. The sign was partially painted when the crew was instructed to move the scaffolding so that concrete could be

poured for an access road. The crew moved the scaffolding 30 feet without disassembling it. An overheadpowerline was located about 10 feet away from the scaffolding. After the concrete hardened, the workers lift-ed the scaffolding to move it back to the sign. The top tier came loose, fell, and contacted the powerline. Allseven workers were knocked away from the scaffolding. Two died; five were hospitalized.

You must take certain precautions when working with scaffolding.

• Scaffolding should not be moved until all potential safety hazards are identified and controlled. In this case,the scaffolding should have been taken apart before it was moved.

• Locking pins must be used to secure tiers to one another.

• Always make sure you have enough time to complete your assignment safely. If you are rushed, you maybe more likely to take deadly short-cuts (such as failing to dismantle scaffolding before moving it).

• Employers must have a written safety program that includes safe work procedures and hazard recognition.

A company was contracted to install wiring and fixtures in a new office complex. The third floor wasbeing prepared in a hurry for a new tenant, and daily changes to the electrical system blueprintswere arriving by fax. The light fixtures in the office were mounted in a metal grid that was fastened

to the ceiling and properly grounded.

A 23-year-old male apprentice electrician was working on a light fixture when he contacted an energizedconductor. He came down from the fiberglass ladder and collapsed. Apparently, he had contacted the “hot”conductor while also in contact with the metal grid. Current passed through his body and into the ground-ed grid. Current always takes a path to ground. In this case, the worker was part of that path.

He was dead on arrival at a nearby hospital. Later, an investigation showed that the victim had cross-wiredthe conductors in the fixture by mistake. This incorrect wiring allowed electricity to flow from a live circuiton the completed section of the building to the circuit on which the victim was working.

Below are some safety procedures that should have been followed in this case. Because they wereignored, the job ended in death.

• Before work begins, all circuits in the immediate work area must be shut off, locked out, and taggedout—then tested to confirm that they are de-energized.

• Wiring done by apprentice electricians should be checked by a journeyman.

• A supervisor should always review changes to an original blueprint in order to identify any new hazardsthat the changes might create.

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Avoid wet working conditions and other dangersRemember that any hazard becomes much more dangerous in dampor wet conditions. To be on the safe side, assume there is dampnessin any work location, even if you do not see water. Even sweat cancreate a damp condition!

❑ Do not work wet—Do not work on circuits or use electricalequipment in damp or wet areas. If necessary, clear the area ofloose material or hanging objects. Cover wet floors with woodenplanking that can be kept dry. Wear insulating rubber boots orshoes. Your hands must be dry when plugging and unpluggingpower cords and extension cords. Do not get cleaning solutionson energized equipment.

❑ Use a GFCI—Always use a GFCI when using portable tools andextension cords.

Avoid overhead powerlines Be very careful not to contact overhead powerlines or other exposedwires. More than half of all electrocutions are caused by contactwith overhead lines. When working in an elevated position nearoverhead lines, avoid locations where you (and any conductiveobject you hold) could contact an unguarded or uninsulated line.You should be at least 10 feet away from high-voltage transmissionlines.

Vehicle operators should also pay attention to overhead wiring.Dump trucks, front-end loaders, and cranes can lift and make contact with overhead lines. If you contact equipment that is touching live wires, you will be shocked and may be killed. If youare in the vehicle, stay inside. Always be aware of what is going onaround you.

Use proper wiring and connectors ❑ Avoid overloads—Do not overload circuits.

❑ Test GFCI’s—Test GFCI’s monthly using the “test” button.

❚ Avoid wet conditions! Even avoiddamp conditions!


Portable GFCI.

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❑ Check switches and insulation—Tools and other equipmentmust operate properly. Make sure that switches and insulatingparts are in good condition.

❑ Use three-prong plugs—Never use a three-prong groundingplug with the third prong broken-off. When using tools thatrequire a third-wire ground, use only three-wire extension cordswith three-prong grounding plugs and three-hole electrical out-lets. Never remove the grounding prong from a plug! You couldbe shocked or expose someone else to a hazard. If you see a cordwithout a grounding prong in the plug, remove the cord fromservice immediately.

❑ Use extension cords properly—If an extension cord must beused, choose one with sufficient ampacity for the tool being used.An undersized cord can overheat and cause a drop in voltage andtool power. Check the tool manufacturer’s recommendations forthe required wire gauge and cord length. Make sure the insulationis intact. To reduce the risk of damage to a cord’s insulation, use

A worker from an electrical service company was changing bulbs in pole-mounted light fixtures in a shop-ping center parking lot. The procedure for installing the bulbs was as follows: The worker would parkthe truck near the first light pole. The truck was equipped with a roof-mounted ladder. The worker would

extend the ladder high enough to change the bulb, then drive to the next pole without lowering the ladder.

After the worker replaced the first bulb, he got back in the truck and drove toward the next light pole. As thetruck moved along, a steel cable attached to the top of the ladder contacted an overhead powerline.The work-er realized something was wrong, stopped the truck, and stepped onto the pavement while still holding ontothe door of the truck. By doing this, he completed the path to ground for the current in the truck. Because theladder was still in contact with the powerline, the entire truck was now energized. He was engulfed in flamesas the truck caught fire. Fire, police, and paramedic units arrived within 5 minutes. Utility workers arrived inabout 10 minutes and de-energized (shut off) the powerline. The victim burned to death at the scene.

Below are some ways to prevent contact with overhead powerlines.

• A safe distance must be maintained between ladders (and other equipment) and overhead lines. OSHArequires that a clearance of at least 10 feet be maintained between aerial ladders and overhead powerlinesof up to 50,000 volts.

• Moving a truck with the ladder extended is a dangerous practice. One way to control this hazard is to installan engine lock that prevents a truck’s engine from starting unless the ladder is fully retracted.

• If there are overhead powerlines in the immediate area, lighting systems that can be serviced from groundlevel are recommended for safety.

• If the worker had been trained properly, he may have known to stay inside the truck.

• Pre-job safety surveys should always be performed to identify and control hazards. In this case, a surveywould have identified the powerlines as a possible hazard, and appropriate hazard control measures (suchas lowering the ladder between installations) could have been taken.

Never use a three-pronggrounding plug with the thirdprong broken off.

480

cords with insulation marked “S” (hard service) rather than cordsmarked “SJ” (junior hard service). Make sure the groundingprong is intact. In damp locations, make sure wires and connec-tors are waterproof and approved for such locations. Do not create a tripping hazard.

❑ Check power cords and extensions—Electrical cords should beinspected regularly using the following procedure:

1. Remove the cord from the electrical power source beforeinspecting.

2. Make sure the grounding prong is present in the plug.

3. Make sure the plug and receptacle are not damaged.

4. Wipe the cord clean with a diluted detergent and examine forcuts, breaks, abrasions, and defects in the insulation.

5. Coil or hang the cord for storage. Do not use any other methods.Coiling or hanging is the best way to avoid tight kinks, cuts, andscrapes that can damage insulation or conductors.

You should also test electrical cords regularly for ground continuityusing a continuity tester as follows:

1. Connect one lead of the tester to the ground prong at one endof the cord.

2. Connect the second lead to the ground wire hole at the otherend of the cord.

3. If the tester lights up or beeps (depending on design), thecord’s ground wire is okay. If not, the cord is damaged andshould not be used.

❑ Do not pull on cords—Always disconnect a cord by the plug.

❑ Use correct connectors—Use electrical plugs and receptaclesthat are right for your current and voltage needs. Connectors aredesigned for specific currents and voltages so that only matchingplugs and receptacles will fit together. This safeguard prevents apiece of equipment, a cord, and a power source with differentvoltage and current requirements from being plugged together.Standard configurations for plugs and receptacles have beenestablished by the National Electric Manufacturers Association(NEMA).

Section 8 Page 63


481

❑ Use locking connectors—Use locking-type attachment plugs,receptacles, and other connectors to prevent them from becomingunplugged.

Use and maintain tools properly Your tools are at the heart of your craft. Tools help you do your jobwith a high degree of quality. Tools can do something else, too.They can cause injury or even death! You must use the right toolsfor the job. Proper maintenance of tools and other equipment is veryimportant. Inadequate maintenance can cause equipment to deterio-rate, creating dangerous conditions. You must take care of your toolsso they can help you and not hurt you.

❑ Inspect tools before using them—Check for cracked casings,dents, missing or broken parts, and contamination (oil, moisture,dirt, corrosion). Damaged tools must be removed from service andproperly tagged. These tools should not be used until they arerepaired and tested.

❚ Maintain tools and equipment.

❚ Inspect your equipment beforeyou use it.

Page 64 Section 8

Locking-type attachment plug.

This cord has beenspliced using a wire nut.Spliced cords are verydangerous!


482

❑ Use the right tool correctly—Use tools correctly and for theirintended purposes. Follow the safety instructions and operatingprocedures recommended by the manufacturer. When working ona circuit, use approved tools with insulated handles. However,DO NOT USE THESE TOOLS TO WORK ON ENERGIZED CIRCUITS. ALWAYS SHUT OFFAND DE-ENERGIZE CIRCUITS BEFORE BEGINNING WORK ON THEM .

❑ Protect your tools—Keep tools and cords away from heat, oil,and sharp objects. These hazards can damage insulation. If a toolor cord heats up, stop using it! Report the condition to a supervi-sor or instructor immediately. If equipment has been repaired,make sure that it has been tested and certified as safe beforeusing it. Never carry a tool by the cord. Disconnect cords bypulling the plug—not the cord!

❑ Use double-insulated tools—Portable electrical tools are classi-fied by the number of insulation barriers between the electricalconductors in the tool and the worker. The NEC permits the useof portable tools only if they have been approved byUnderwriter’s Laboratories (UL Listed). Equipment that has twoinsulation barriers and no exposed metal parts is called double-insulated. When used properly, double-insulated tools providereliable shock protection without the need for a third ground

❚ Use the right tools and equipment.

❚ Do not work on energized circuits.

Section 8 Page 65

A n employee was climbing a metal ladder to hand an electric drill to the journeyman installer ona scaffold about 5 feet above him. When the victim reached the third rung of the ladder, hereceived an electrical shock that killed him. An investigation showed

that the grounding prong was missing from the extension cord attached tothe drill. Also, the cord’s green grounding wire was, at times, contacting theenergized black wire. Because of this contact with the "hot" wire, the entirelength of the grounding wire and the drill’s frame became energized.The drillwas not double-insulated.

To avoid deadly incidents like this one, take these precautions:

• Make certain that approved GFCI’s or equipment grounding systems areused at construction sites.

• Use equipment that provides a permanent and continuous path to ground.Any fault current will be safely diverted along this path.

• Inspect electrical tools and equipment daily and remove damaged or defective equipment from use right away.

Don’t work on energized circuits like this one! Always follow correct lock-out/tagout procedures.


483

wire. Power tools with metal housings or only one layer of effectiveinsulation must have a third ground wire and three-prong plug.

❑ Use multiple safe practices—Remember: A circuit may not bewired correctly. Wires may contact other “hot” circuits. Someoneelse may do something to place you in danger. Take all possibleprecautions.

Wear correct PPEOSHA requires that you be provided with personal protective equip-ment. This equipment must meet OSHA requirements and be appro-priate for the parts of the body that need protection and the workperformed. There are many types of PPE: rubber gloves, insulatingshoes and boots, face shields, safety glasses, hard hats, etc. Even iflaws did not exist requiring the use of PPE, there would still beevery reason to use this equipment. PPE helps keep you safe. It isthe last line of defense between you and the hazard.

❚ Wear and maintain PPE.

Page 66 Section 8

A 22-year-old male carpenter was building the wooden framework of a laundry building. He was usingportable power tools. Electricity was supplied to the tools by a temporary service pole 50 feet away.The service pole had not been inspected and was not in compliance. It was also not grounded. The

carpenter plugged a “homemade” cord into the service pole and then plugged a UL-approved cord into thehomemade cord. His power saw was plugged into the UL-approved cord.

The site was wet. Humidity was high and the carpenter was sweating. Reportedly, he was mildly shockedthroughout the morning and replaced the extension cord he was using in an effort to stop the shocks. At onepoint, as he was climbing down a makeshift ladder constructed from a floor truss, he shifted the power sawfrom his right hand to his left hand and was shocked. He fell from the ladder into a puddle of water, still hold-ing the saw. The current had caused his hand to contract, and he was “locked” to the saw. A co-worker disconnected the power cord to the saw. CPR was given, but the shock was fatal.

Attention to these general safety principles could have prevented this death.

• Any and all electrical equipment involved in a malfunction should be taken out of service immediately. Thecarpenter should have taken the saw out of service, not just the extension cord. (As it turns out, the sawwas the source of the shocks, not the cord.)

• Although the homemade extension cord does not seem to have contributed to this incident, it should nothave been used.

• The floor truss should not have been used as a ladder. For climbing, use only approved ladders or otherequipment designed specifically for climbing.

• Do not work in wet areas. The water should have been removed from the floor as soon as it was found.Humidity and perspiration can also be hazards. Try to stay as dry as possible, be alert, and take action toprotect yourself when needed.

• OSHA requires that all receptacles at construction sites that are not part of the permanent wiring haveGFCI’s.

• Be aware that shocks can cause you to lose your balance and fall, often resulting in more severe injury.


484

❑ Wear safety glasses—Wear safety glasses to avoid eye injury.

❑ Wear proper clothing—Wear clothing that is neither floppy nortoo tight. Loose clothing will catch on corners and rough sur-faces. Clothing that binds is uncomfortable and distracting.

❑ Contain and secure loose hair—Wear your hair in such a waythat it does not interfere with your work or safety.

❑ Wear proper foot protection—Wear shoes or boots that havebeen approved for electrical work. (Tennis shoes will not protectyou from electrical hazards.) If there are non-electrical hazardspresent (nails on the floor, heavy objects, etc.), use footwear thatis approved to protect against these hazards as well.

❑ Wear a hard hat—Wear a hard hat to protect your head frombumps and falling objects. Hard hatsmust be worn with the bill forwardto protect you properly.

❑ Wear hearing protectors—Wearhearing protectors in noisy areas toprevent hearing loss.

❑ Follow directions—Follow themanufacturer’s directions for clean-ing and maintaining PPE.

❑ Make an effort—Search out anduse any and all equipment that willprotect you from shocks and otherinjuries.

❚ Think about what you are doing.

❚ PPE is only effective when usedcorrectly.

Section 8 Page 67

Wear safety glasses to avoid eye injury.

Arcing electrical burnsthrough the victim’sshoe and around therubber sole.

Don’t wear hardhats backwards!


485

Page 68 Section 8

PPE is the last line of defense against workplace hazards. OSHA defines PPE as "equipment for the eyes, face, head, and extremities, protective clothing, respiratory devices, protective shields andbarriers." Many OSHA regulations state that PPE must meet criteria set by the American NationalStandards Institute (ANSI).

Head ProtectionOSHA requires that head protection(hard hats) be worn if there is a risk ofhead injury from electrical burns or falling/flyingobjects.

Aren’t all hard hats the same?No. You must wear the right hat for the job. All hardhats approved for electrical work made since 1997are marked "Class E." Hard hats made before 1997are marked "Class B." These markings will be on alabel inside the helmet or stamped into the helmetitself. Newer hats may also be marked "Type 1" or"Type 2." Type 1 hard hats protect you from impactson the top of your head. Type 2 hard hats protectyou from impacts on the top and sides of your head.

How do I wear and care for myhard hat?Always wear your hat with the bill forward. (Hatsare tested in this position.) If you wear a hat differ-ently, you may not be fully protected. The hatshould fit snugly without being too tight. You shouldclean and inspect your hard hatregularly according to the man-ufacturer’s instructions. Checkthe hat for cracks, dents, frayedstraps, and dulling of the finish. These conditions canreduce protection. Use onlymild soap and water for clean-ing. Heavy-duty cleaners andother chemicals can damagethe hat.

HEAD PROTECTION

Class E, Type 1 hard hat. Class B hard hat.

Don’t wear another hatunder your hard hat!

PPE Fact Sheet—The Right Equipment—Head to

486

Section 8 Page 69

Do not "store" anything (gloves, wallet, etc.) in thetop of your hard hat while you are wearing it. Thespace between the inside harness and the top of thehard hat must remain open to protect you. Do notput stickers on your hat (the glue can weaken the

helmet) and keep it out of direct sunlight. If youwant to express your personality, hard hats come inmany colors and can be imprinted with customdesigns by the manufacturer. Some hats are avail-able in a cowboy hat design or with sports logos.

Use your head and protect your head!

Never “store” anything in the topof your hard hat while you arewearing it.

Class B hard hat in a cowboyhat design.

Keep your hard hat out of direct sunlight when you are not wearing it!

Toe

487

Foot ProtectionWorkers must wear protective footwearwhen there is a risk of foot injury fromsharp items or falling/rolling objects—or when electrical hazards are present. Aswith hard hats, always follow the manufac-turer’s instructions for cleaning and mainte-nance of footwear. Remember that cuts, holes, wornsoles, and other damage can reduce protection.

How do I choose the right footwear? The footwear must be ANSI approved. ANSIapproval codes are usually printed inside the tongueof the boot or shoe. Footwear will be marked "EH"if it is approved for electrical work. (The ANSI

approval stamp alone does not neces-sarily mean the footwear offers protec-tion from electrical hazards.) Note thatfootwear made of leather must be keptdry to protect you from electrical haz-

ards, even if it is marked "EH."

What about non-electrical hazards? All ANSI approved footwear has a protective toeand offers impact and compression protection. Butthe type and amount of protection is not always thesame. Different footwear protects you in differentways. Check the product’s labeling or consult themanufacturer to make sure the footwear will protect you from the hazards you face.

FOOT PROTECTION

Don’t take risks because you are wearing PPE.PPE is the last line of defense against injury!

C = Compression rating[This code is more complex thanthe others. Here is how to read it:

30 = 1,000 pounds;50 = 1,750;75 = 2,500 (in this example)]

MT = Metatarsal (top of the foot)protection rating (75 foot pounds inthis example—can also be 30 or 50)

ANSI Z41 = ANSI footwearprotection standardPT = Protective Toe section

of the standard91 = year of the standard

(in this example 1991)

M = Male footwear(F = Female footwear)

I = Impact rating(75 foot pounds inthis example—canalso be 30 or 50)

EH = protection from Electrical Hazards

Page 70 Section 8

PPE Fact Sheet (continued)S A F E T Y M O D E L S TAG E 3 — C O N T R O L L I N G

488

Summary of Section 8 Control hazards through safe work practices.

Plan your work and plan for safety.

Avoid wet working conditions and other dangers.

Avoid overhead powerlines.

Use proper wiring and connectors.

Use and maintain tools properly.

Wear correct PPE.

Section 8 Page 71


489

Page 72

Glossary of Terms ampacitymaximum amount of current a wire can carry safely without over-heating

amperagestrength of an electrical current, measured in amperesampere (amp)unit used to measure current

arc-blastexplosive release of molten material from equipment caused byhigh-amperage arcs

arcingluminous electrical discharge (bright, electrical sparking) throughthe air that occurs when high voltages exist across a gap betweenconductors

AWGAmerican Wire Gauge—measure of wire size

bondingjoining electrical parts to assure a conductive path

bonding jumperconductor used to connect parts to be bonded

circuitcomplete path for the flow of current

circuit breakerovercurrent protection device that automatically shuts off the currentin a circuit if an overload occurs

conductormaterial in which an electrical current moves easily

CPRcardiopulmonary resuscitation—emergency procedure that involvesgiving artificial breathing and heart massage to someone who is notbreathing or does not have a pulse (requires special training)currentmovement of electrical charge

de-energizeshutting off the energy sources to circuits and equipment and depleting any stored energy

double-insulatedequipment with two insulation barriers and no exposed metal parts

energized (live, “hot”)similar terms meaning that a voltage is present that can cause a current, so there is a possibility of getting shocked

fault currentany current that is not in its intended path

490

Page 73

Glossary of Terms (continued)fixed wiringpermanent wiring installed in homes and other buildings

flexible wiringcables with insulated and stranded wire that bends easily

fuse overcurrent protection device that has an internal part that melts andshuts off the current in a circuit if there is an overload

GFCIground fault circuit interrupter—a device that detects current leakage from a circuit to ground and shuts the current off

groundphysical electrical connection to the earth

ground faultloss of current from a circuit to a ground connection

ground potentialvoltage a grounded part should have; 0 volts relative to ground

guardingcovering or barrier that separates you from live electrical parts

insulationmaterial that does not conduct electricity easily

leakage currentcurrent that does not return through the intended path, but instead"leaks" to ground

lock-outapplying a physical lock to the energy sources of circuits and equip-ment after they have been shut off and de-energized

milliampere (milliamp or mA)

1/1,000 of an ampere

NECNational Electrical Code—comprehensive listing of practices to pro-tect workers and equipment from electrical hazards such as fire andelectrocution

neutralat ground potential (0 volts) because of a connection to ground

ohmunit of measurement for electrical resistance

OSHAOccupational Safety and Health Administration—Federal agency inthe U.S. Department of Labor that establishes and enforces work-place safety and health regulations

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Page 74

Glossary of Terms (continued)overcurrent protection devicedevice that prevents too much current in a circuitoverloadtoo much current in a circuit

power

amount of energy used each second, measured in watts

PPEpersonal protective equipment (eye protection, hard hat, specialclothing, etc.)

qualified personsomeone who has received mandated training on the hazards and onthe construction and operation of equipment involved in a task

resistancematerial’s ability to decrease or stop electrical current

risk

chance that injury or death will occur

shocking currentelectrical current that passes through a part of the body

short

low-resistance path between a live wire and the ground, or betweenwires at different voltages (called a fault if the current is unintended)

tag-outapplying a tag that alerts workers that circuits and equipment havebeen locked outtripautomatic opening (turning off) of a circuit by a GFCI or circuitbreaker

voltagemeasure of electrical force

wire gaugewire size or diameter (technically, the cross-sectional area)

Endnotes 1. Castillo DN [1995]. NIOSH alert: preventing death and injuries of adolescent

workers. Cincinnati, OH: U.S. Department of Health and Human Services,Public Health Service, Centers for Disease Control and Prevention, NationalInstitute for Occupational Safety and Health, DHHS (NIOSH) Publication No. 95-125.

2. Lee RL [1973]. Electrical safety in industrial plants. Am Soc Safety Eng J18(9):36-42.

3. DOL [1997]. Controlling electrical hazards. Washington, DC: U.S. Departmentof Labor, Occupational Safety and Health Administration.

492

Appendix OSHA Standards

OSHA occupational safety and health standards for GeneralIndustry are located in the Code of Federal Regulations(CFR),Title 29, Part 1910 (abbreviated as 29 CFR 1910). Standardsfor Construction are located in Part 1926 (abbreviated as 29CFR 1926). The full text of these standards is available onOSHA's Web site: www.osha.gov.

OSHA standards related to electrical safety for GeneralIndustry are listed below:

Subpart S—Electrical

GENERAL

1910.301 - Introduction

DESIGN SAFETY STANDARDS FOR ELECTRICAL SYSTEMS

1910.302 – Electric utilization systems1910.303 – General requirements 1910.304 – Wiring design and protection 1910.305 – Wiring methods, components, and equipment for

general use1910.306 – Specific purpose equipment and installations1910.307 – Hazardous (classified) locations1910.308 – Special systems

SAFETY-RELATED WORK PRACTICES

1910.331 – Scope 1910.332 – Training 1910.333 – Selection and use of work practices 1910.334 – Use of equipment1910.335 – Safeguards for personnel protection

Subpart J—General Environment Controls 1910.147 – The control of hazardous energy (lock-out/tag-out)1910.147 – Appendix A—Typical minimal lock-out

procedures

Subpart R—Special Industries1910.268 – Telecommunications1910.269 – Electric power generation, transmission, and dis-

tribution

OSHA standards related to electrical safety for Construction arelisted below:

Subpart K—Electrical

GENERAL

1926.400 – Introduction

INSTALLATION SAFETY REQUIREMENTS

1926.402 – Applicability1926.403 – General requirements1926.404 – Wiring design and protection1926.405 – Wiring methods, components, and equipment for

general use1926.406 – Specific purpose equipment and installations1926.407 – Hazardous (classified) locations1926.408 – Special systems

SAFETY-RELATED WORK PRACTICES

1926.416 – General requirements1926.417 – Lock-out and tagging circuits

SAFETY-RELATED MAINTENANCE AND ENVIRONMENTAL

CONSIDERATIONS

1926.431 – Maintenance of equipment 1926.432 – Environmental deterioration of equipment

SAFETY REQUIREMENTS FOR SPECIAL EQUIPMENT

1926.441 – Batteries and battery charging

DEFINITIONS

1926.449 – Definitions applicable to this subpart

Subpart V—Power Transmission andDistribution1926.950 – General requirements1926.951 – Tools and protective equipment1926.952 – Mechanical equipment1926.953 – Material handling1926.954 – Grounding for protection of employees1926.955 – Overhead lines1926.956 – Underground lines1926.957 – Construction in energized substations1926.958 – External load helicopters1926.959 – Lineman's body belts, safety straps, and lanyards1926.960 – Definitions applicable to this subpart

Page 75

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Page 76

Aaluminum wire hazard 24amp 6ampacity 24ampere 6arc-blast 12arc-fault circuit breaker 46arcing 12, 29arthritis 30AWG 39

Bbonding 49bonding jumper 50burns, arc 12, 15burns, electrical 6, 10, 12, 15burns, thermal contact 12, 15

Ccable, 240v 4cardiopulmonary resuscitation17carpal tunnel syndrome 31circuit 2circuit breaker 29, 34, 50circuit breaker, and leakage current 28clearance distance 26clues of electrical hazards 34 clues,

blown fuses 34tripped circuit breakers 34tripped GFCI 35warm extension cord 34warm junction box 35warm tools and wire 34worn insulation 35

Code of Federal Regulations 75concussion 12conductor 3controlling hazards 19, 21, 36, 54CPR (see cardiopulmonary

resuscitation)CFR (see Code of Federal Regulations)current,

calculating 42current 2effects on body 7path through body 8, 9, 10

current leakage 47cuts 31

Dde-energizing circuits 55

Eelectrical hazards,

aluminum wire 24damaged hand tool 31, 34damaged tool 29defective insulation 26exposed electrical parts 24improper grounding 27inadequate wiring 24overhead powerline 25overload 28wet conditions 29

electrical shock,amount 6, 11current density 9duration 6, 7, 11path 8, 9, 10, 11receiving 2

electrical shock—what to do for 16electrocution, deaths 1, 7, 10energized 2evaluating hazards 19, 21, 34evaluating risk 34extension cord 24, 34, 42, 46, 63

Ffalls 56fault 27fault, low current 47fire extinguisher, types 14fires, electrical 14, 24, 28, 29fires—what to do 14fixed wiring 40flexible wiring 41foot protection70freezing 6fuse 29, 34, 51

GGFCI

(see ground fault circuit interrupter)ground 2ground connection 47ground fault 28ground fault circuit interrupter

28, 34, 48, 61ground potential 27grounding 27, 28, 46grounding path 47guarding 43

Hhard hat68hazards (also see electrical hazards),

chemical 30control (see controlling hazards)falling objects 32falls 32inadequate wiring 24lifting 32overhead work 30particles 32

hazardous environments 51

Iimpedance 8insulation 26, 44insulation damage 45isolation 43

Jjewelry 56jumper, bonding 49

Kkill switches 17

Lladder safety58leakage current 28live 2lock-out/tag-out 37, 38lock-out/tag-out checklist38low back pain 31

I N D E X

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MmA 6milliamp 6milliampere 6

NNational Electrical Code 15National Electrical Safety Code 19NEC (see National Electrical Code)NEMA 63NESC (see National Electrical

Safety Codenonconductive material 28

OOccupational Safety and HealthAdministration 15ohm 8OSHA (see Occupational Safety and

Health Administration)overhead power lines 25, 61overload 28

Ppersonal protective equipment

31, 66, 68, 80perspiration 30plugs, three-prong 62power 42power rating 42PPE

(see personal protective equipment)

Rrecognizing hazards 18, 21, 22resistance 8resistance, effect on current 8respiratory paralysis 6risk 34risk evaluation 34

Ssafe work environment 19, 36safe work practices 19, 54safety model, overview 18shock (see electrical shock)shocking current 6short 34

Ttendinitis 30tools 64tools, double-insulated 65

Vventricular fibrillation 6voltage,

high 7, 12low 6voltage 2

Wwet conditions 29, 61wire gauge 24wire size 24

I N D E X

©P. Barber/CMSP—9

Richard Carlson—23a, 26b, 57, 65a

©Corbis Images—6

©M. English/CMSP—10

Thaddeus W. Fowler—34, 46a, 47a, 51

Cat Goldberg—cover, 5, 20, 25a, 26a, 27, 30, 31,32a, 37a, 38ab, 43c, 49, 50, 55, 56, 58b, 59a,64b, 65b, 67ac, 68abc, 69ac, 70

Karen K. Miles—14bc, 18, 19, 23b, 24, 25b,37b, 39, 48, 58c, 61, 62, 64a, 69b

©PhotoDisc—1, 2, 3, 8, 14a, 28ab, 29, 32b, 40,43a, 44, 46b, 47b, 58a, 59bc, 66

©PhotoQuest—25c, 43b

R.K.Wright, M.D.—www.emedicine.com12, 67b

Photo and Graphics Credits

495

496

497

To receive information about occupational safety and health problems, call NIOSH at

1-800-35-NIOSH (1-800-356-4674)Fax number: (513) 533-8573E-mail: [email protected]

or visit the NIOSH Web site at www.cdc.gov/niosh

DHHS (NIOSH) Publication No. 2002-123

Delivering on the Nation’s promise:Safety and health at work for all peoplethrough research and prevention

498

OSHA 3252-05N 2005

499

WORKER SAFETY SERIES

ConstructionNearly 6.5 million people work at approximate-ly 252,000 construction sites across the nationon any given day. The fatal injury rate for theconstruction industry is higher than the nationalaverage in this category for all industries.

Potential hazards for workers in constructioninclude:

• Falls (from heights);• Trench collapse;• Scaffold collapse;• Electric shock and arc flash/arc blast;• Failure to use proper personal protective

equipment; and• Repetitive motion injuries.

Occupational Safety and Health AdministrationU.S. Department of Labor

www.osha.gov

500

CONSTRUCTION 11

Hazards & SolutionsFor construction, the 10 OSHA stan-dards most frequently included in theagency’s citations in FY 2004 were:

1. Scaffolding2. Fall protection (scope, application,

definitions)3. Excavations (general requirements)4. Ladders5. Head protection6. Excavations (requirements for

protective systems)7. Hazard communication8. Fall protection (training require-

ments)9. Construction (general safety and

health provisions)10.Electrical (wiring methods, design

and protection)


501

ScaffoldingHazard: When scaffolds are not erected orused properly, fall hazards can occur. About2.3 million construction workers frequentlywork on scaffolds. Protecting these workersfrom scaffold-related accidents would preventan estimated 4,500 injuries and 50 fatalitieseach year.

Solutions:

• Scaffold must be sound, rigid and sufficientto carry its own weight plus four times themaximum intended load without settling ordisplacement. It must be erected on solidfooting.

• Unstable objects, such as barrels, boxes,loose bricks or concrete blocks must not beused to support scaffolds or planks.

• Scaffold must not be erected, moved, dis-mantled or altered except under the super-vision of a competent person.

• Scaffold must be equipped with guardrails,midrails and toeboards.

• Scaffold accessories such as braces, brack-ets, trusses, screw legs or ladders that aredamaged or weakened from any causemust be immediately repaired or replaced.

• Scaffold platforms must be tightly plankedwith scaffold plank grade material or equiv-alent.

• A “competent person” must inspect thescaffolding and, at designated intervals,reinspect it.

• Rigging on suspension scaffolds must beinspected by a competent person beforeeach shift and after any occurrence thatcould affect structural integrity to ensurethat all connections are tight and that no

2 WORKER SAFETY SERIES


502

damage to the rigging has occurred sinceits last use.

• Synthetic and natural rope used in suspen-sion scaffolding must be protected fromheat-producing sources.

• Employees must be instructed about thehazards of using diagonal braces as fall protection.

• Scaffold can be accessed by using laddersand stairwells.

• Scaffolds must be at least 10 feet from electric power lines at all times.

CONSTRUCTION 3


503


Fall ProtectionHazard: Each year, falls consistently accountfor the greatest number of fatalities in theconstruction industry. A number of factors areoften involved in falls, including unstableworking surfaces, misuse or failure to use fallprotection equipment and human error.Studies have shown that using guardrails, fallarrest systems, safety nets, covers andrestraint systems can prevent many deathsand injuries from falls.

Solutions:

• Consider using aerial lifts or elevated plat-forms to provide safer elevated workingsurfaces;

• Erect guardrail systems with toeboards andwarning lines or install control line systemsto protect workers near the edges of floorsand roofs;

• Cover floor holes; and/or

• Use safety net systems or personal fallarrest systems (body harnesses).


504


LaddersHazard: Ladders and stairways are anothersource of injuries and fatalities among con-struction workers. OSHA estimates that thereare 24,882 injuries and as many as 36 fatali-ties per year due to falls on stairways and lad-ders used in construction. Nearly half of theseinjuries were serious enough to require timeoff the job.

Solutions:

• Use the correct ladder for the task.

• Have a competent person visually inspect aladder before use for any defects such as:■ Structural damage, split/bent side rails,

broken or missing rungs/steps/cleats andmissing or damaged safety devices;

■ Grease, dirt or other contaminants thatcould cause slips or falls;

■ Paint or stickers (except warning labels)that could hide possible defects.

• Make sure that ladders are long enough tosafely reach the work area.

• Mark or tag (“Do Not Use”) damaged ordefective ladders for repair or replacement,or destroy them immediately.

• Never load ladders beyond the maximumintended load or beyond the manufacturer’srated capacity.

• Be sure the load rating can support theweight of the user, including materials andtools.

• Avoid using ladders with metallic compo-nents near electrical work and overheadpower lines.

CONSTRUCTION 5

505


StairwaysHazard: Slips, trips and falls on stairways area major source of injuries and fatalitiesamong construction workers.

Solutions:

• Stairway treads and walkways must be freeof dangerous objects, debris and materials.

• Slippery conditions on stairways and walk-ways must be corrected immediately.

• Make sure that treads cover the entire stepand landing.

• Stairways having four or more risers or ris-ing more than 30 inches must have at leastone handrail.


506

SLOPING. Maximum allowable slopes for excavationsless than 20 ft. (6.09 m) based on soil type and angleto the horizontal are as follows:

TABLE V:2-1. ALLOWABLE SLOPES

Source: OSHA Technical Manual, Section V, Chap. 2, Excavations:Hazard Recognition in Trenching and Shoring (Jan. 1999).


TrenchingHazard: Trench collapses cause dozens of fatal-ities and hundreds of injuries each year.Trenching deaths rose in 2003.

Solutions:

• Never enter an unprotected trench.

• Always use a protective system for trenches 5feet deep or greater.

• Employ a registered professional engineer todesign a protective system for trenches 20feet deep or greater.

• Protective Systems:■ Sloping to protect workers by cutting back

the trench wall at an angle inclined awayfrom the excavation not steeper than aheight/depth ratio of 11

2 :1, according to thesloping requirements for the type of soil.

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Soil type Height/Depth ratio Slope angle

Stable Rock Vertical 90º(granite or sandstone)Type A

34 :1 53º

(clay)Type B 1:1 45º(gravel, silt)Type C 11

2:1 34º(sand)Type A (short-term)

12 :1 63º

(For a maximum excavation depth of 12 ft.)

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■ Shoring to protect workers by installingsupports to prevent soil movement fortrenches that do not exceed 20 feet indepth.

■ Shielding to protect workers by usingtrench boxes or other types of supportsto prevent soil cave-ins.

• Always provide a way to exit a trench--suchas a ladder, stairway or ramp--no more than25 feet of lateral travel for employees in thetrench.

• Keep spoils at least two feet back from theedge of a trench.

• Make sure that trenches are inspected by acompetent person prior to entry and afterany hazard-increasing event such as a rain-storm, vibrations or excessive surchargeloads.


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CranesHazard: Significant and serious injuries mayoccur if cranes are not inspected before useand if they are not used properly. Often theseinjuries occur when a worker is struck by anoverhead load or caught within the crane’sswing radius. Many crane fatalities occurwhen the boom of a crane or its load linecontact an overhead power line.

Solutions:

• Check all crane controls to insure properoperation before use.

• Inspect wire rope, chains and hook for anydamage.

• Know the weight of the load that the craneis to lift.

• Ensure that the load does not exceed thecrane’s rated capacity.

• Raise the load a few inches to verify balanceand the effectiveness of the brake system.

• Check all rigging prior to use; do not wraphoist ropes or chains around the load.

• Fully extend outriggers.

• Do not move a load over workers.

• Barricade accessible areas within thecrane’s swing radius.

• Watch for overhead electrical distributionand transmission lines and maintain a safeworking clearance of at least 10 feet fromenergized electrical lines.

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Hazard CommunicationHazard: Failure to recognize the hazardsassociated with chemicals can cause chemicalburns, respiratory problems, fires and explo-sions.

Solutions:

• Maintain a Material Safety Data Sheet(MSDS) for each chemical in the facility.

• Make this information accessible to employ-ees at all times in a language or formatsthat are clearly understood by all affectedpersonnel.

• Train employees on how to read and usethe MSDS.

• Follow manufacturer’s MSDS instructionsfor handling hazardous chemicals.

• Train employees about the risks of eachhazardous chemical being used.

• Provide spill clean-up kits in areas wherechemicals are stored.

• Have a written spill control plan.

• Train employees to clean up spills, protectthemselves and properly dispose of usedmaterials.

• Provide proper personal protective equip-ment and enforce its use.

• Store chemicals safely and securely.


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ForkliftsHazard: Approximately 100 employees arefatally injured and approximately 95,000employees are injured every year while oper-ating powered industrial trucks. Forklift turn-over accounts for a significant number ofthese fatalities.

Solutions:

• Train and certify all operators to ensure thatthey operate forklifts safely.

• Do not allow any employee under 18 yearsold to operate a forklift.

• Properly maintain haulage equipment,including tires.

• Do not modify or make attachments thataffect the capacity and safe operation of theforklift without written approval from theforklift’s manufacturer.

• Examine forklift truck for defects beforeusing.

• Follow safe operating procedures for pick-ing up, moving, putting down and stackingloads.

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• Drive safely--never exceed 5 mph and slowdown in congested or slippery surfaceareas.

• Prohibit stunt driving and horseplay.

• Do not handle loads that are heavier thanthe capacity of the industrial truck.

• Remove unsafe or defective forklift trucksfrom service.

• Operators shall always wear seatbelts.

• Avoid traveling with elevated loads.

• Assure that rollover protective structure isin place.

• Make certain that the reverse signal alarm is operational and audible above the sur-rounding noise level.

Head ProtectionHazard: Serious head injuries can result fromblows to the head.

Solution: • Be sure that workers wear hard hats where

there is a potential for objects falling fromabove, bumps to their heads from fixedobjects, or accidental head contact withelectrical hazards.



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Safety ChecklistsThe following checklists may helpyou take steps to avoid hazards thatcause injuries, illnesses and fatalities.As always, be cautious and seek helpif you are concerned about a poten-tial hazard.

Personal ProtectiveEquipment (PPE)

Eye and Face Protection❏ Safety glasses or face shields are worn

anytime work operations can cause for-eign objects getting into the eye such asduring welding, cutting, grinding, nailing(or when working with concrete and/orharmful chemicals or when exposed toflying particles).

❏ Eye and face protectors are selectedbased on anticipated hazards.

❏ Safety glasses or face shields are wornwhen exposed to any electrical hazardsincluding work on energized electricalsystems.

Foot Protection❏ Construction workers should wear work

shoes or boots with slip-resistant andpuncture-resistant soles.

❏ Safety-toed footwear is worn to preventcrushed toes when working aroundheavy equipment or falling objects.

Hand Protection❏ Gloves should fit snugly.

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❏ Workers wear the right gloves for the job(for example, heavy-duty rubber glovesfor concrete work, welding gloves forwelding, insulated gloves and sleeveswhen exposed to electrical hazards).

Head Protection ❏ Workers shall wear hard hats where there

is a potential for objects falling fromabove, bumps to their heads from fixedobjects, or of accidental head contactwith electrical hazards.

❏ Hard hats are routinely inspected fordents, cracks or deterioration.

❏ Hard hats are replaced after a heavy blowor electrical shock.

❏ Hard hats are maintained in good condition.

Scaffolding❏ Scaffolds should be set on sound footing.

❏ Damaged parts that affect the strength ofthe scaffold are taken out of service.

❏ Scaffolds are not altered.

❏ All scaffolds should be fully planked.

❏ Scaffolds are not moved horizontallywhile workers are on them unless theyare designed to be mobile and workershave been trained in the proper proce-dures.

❏ Employees are not permitted to work onscaffolds when covered with snow, ice, orother slippery materials.

❏ Scaffolds are not erected or moved within10 feet of power lines.

❏ Employees are not permitted to work onscaffolds in bad weather or high winds


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unless a competent person has deter-mined that it is safe to do so.

❏ Ladders, boxes, barrels, buckets or othermakeshift platforms are not used to raisework height.

❏ Extra material is not allowed to build upon scaffold platforms.

❏ Scaffolds should not be loaded withmore weight than they were designed tosupport.

Electrical Safety❏ Work on new and existing energized

(hot) electrical circuits is prohibited untilall power is shut off and grounds areattached.

❏ An effective Lockout/Tagout system is inplace.

❏ Frayed, damaged or worn electrical cordsor cables are promptly replaced.

❏ All extension cords have groundingprongs.

❏ Protect flexible cords and cables fromdamage. Sharp corners and projectionsshould be avoided.

❏ Use extension cord sets used withportable electric tools and appliancesthat are the three-wire type and designedfor hard or extra-hard service. (Look forsome of the following letters imprintedon the casing: S, ST, SO, STO.)

❏ All electrical tools and equipment aremaintained in safe condition and checkedregularly for defects and taken out ofservice if a defect is found.

❏ Do not bypass any protective system ordevice designed to protect employeesfrom contact with electrical energy.

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❏ Overhead electrical power lines are locat-ed and identified.

❏ Ensure that ladders, scaffolds, equipmentor materials never come within 10 feet ofelectrical power lines.

❏ All electrical tools must be properlygrounded unless they are of the doubleinsulated type.

❏ Multiple plug adapters are prohibited.

Floor and Wall Openings❏ Floor openings (12 inches or more) are

guarded by a secured cover, a guardrailor equivalent on all sides (except atentrances to stairways).

❏ Toeboards are installed around the edgesof permanent floor openings (where per-sons may pass below the opening).

Elevated Surfaces❏ Signs are posted, when appropriate,

showing the elevated surface loadcapacity.

❏ Surfaces elevated more than 48 inchesabove the floor or ground have standardguardrails.

❏ All elevated surfaces (beneath which peo-ple or machinery could be exposed tofalling objects) have standard 4-inch toe-boards.

❏ A permanent means of entry and exitwith handrails is provided to elevatedstorage and work surfaces.

❏ Material is piled, stacked or racked in away that prevents it from tipping, falling,collapsing, rolling or spreading.


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Hazard Communication❏ A list of hazardous substances used in

the workplace is maintained and readilyavailable at the worksite.

❏ There is a written hazard communicationprogram addressing Material Safety DataSheets (MSDS), labeling and employeetraining.

❏ Each container of a hazardous substance(vats, bottles, storage tanks) is labeledwith product identity and a hazard warn-ing(s) (communicating the specific healthhazards and physical hazards).

❏ Material Safety Data Sheets are readilyavailable at all times for each hazardoussubstance used.

❏ There is an effective employee trainingprogram for hazardous substances.

Crane Safety❏ Cranes and derricks are restricted from

operating within 10 feet of any electricalpower line.

❏ The upper rotating structure supportingthe boom and materials being handled isprovided with an electrical ground whileworking near energized transmitter tow-ers.

❏ Rated load capacities, operating speedand instructions are posted and visible tothe operator.

❏ Cranes are equipped with a load chart.

❏ The operator understands and uses theload chart.

❏ The operator can determine the angleand length of the crane boom at all times.

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❏ Crane machinery and other riggingequipment is inspected daily prior to useto make sure that it is in good condition.

❏ Accessible areas within the crane’s swingradius are barricaded.

❏ Tag lines are used to prevent dangerousswing or spin of materials when raised orlowered by a crane or derrick.

❏ Illustrations of hand signals to crane andderrick operators are posted on the jobsite.

❏ The signal person uses correct signals forthe crane operator to follow.

❏ Crane outriggers are extended whenrequired.

❏ Crane platforms and walkways have anti-skid surfaces.

❏ Broken, worn or damaged wire rope isremoved from service.

❏ Guardrails, hand holds and steps are pro-vided for safe and easy access to andfrom all areas of the crane.

❏ Load testing reports/certifications areavailable.

❏ Tower crane mast bolts are properlytorqued to the manufacturer’s specifica-tions.

❏ Overload limits are tested and correctlyset.

❏ The maximum acceptable load and thelast test results are posted on the crane.

❏ Initial and annual inspections of all hoist-ing and rigging equipment are performedand reports are maintained.

❏ Only properly trained and qualified oper-ators are allowed to work with hoistingand rigging equipment.


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Forklifts❏ Forklift truck operators are competent to

operate these vehicles safely as demon-strated by their successful completion oftraining and evaluation.

❏ No employee under 18 years old isallowed to operate a forklift.

❏ Forklifts are inspected daily for propercondition of brakes, horns, steering,forks and tires.

❏ Powered industrial trucks (forklifts) meetthe design and construction requirementsestablished in American NationalStandards Institute (ANSI) for PoweredIndustrial Trucks, Part II ANSI B56.1-1969.

❏ Written approval from the truck manufac-turer is obtained for any modification oradditions which affect capacity and safeoperation of the vehicle.

❏ Capacity, operation and maintenanceinstruction plates, tags or decals arechanged to indicate any modifications oradditions to the vehicle.

❏ Battery charging is conducted in areasspecifically designated for that purpose.

❏ Material handling equipment is providedfor handling batteries, including convey-ors, overhead hoists or equivalentdevices.

❏ Reinstalled batteries are properly posi-tioned and secured in the truck.

❏ Smoking is prohibited in battery chargingareas.

❏ Precautions are taken to prevent openflames, sparks or electric arcs in batterycharging areas.

❏ Refresher training is provided and anevaluation is conducted whenever a fork-

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lift operator has been observed operatingthe vehicle in an unsafe manner andwhen an operator is assigned to drive adifferent type of truck.

❏ Load and forks are fully lowered, controlsneutralized, power shut off and brakes setwhen a powered industrial truck is leftunattended.

❏ There is sufficient headroom for the fork-lift and operator under overhead installa-tions, lights, pipes, sprinkler systems, etc.

❏ Overhead guards are in place to protectthe operator against falling objects.

❏ Trucks are operated at a safe speed.

❏ All loads are kept stable, safely arrangedand fit within the rated capacity of thetruck.

❏ Unsafe and defective trucks are removedfrom service.



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Construction Safety &Health Resources

Most resource materials can be foundon the OSHA website: www.osha.gov

PublicationsPublications can be downloaded or ordered at:http://www.osha.gov/pls/publications/pubindex.list

A Guide to Scaffold Use in the Construction

Industry

OSHA Publication 3150 (Revised 2002), 2.1 MBPDF, 73 pages.Booklet in question-and-answer format high-lights information about scaffold safety.http://www.osha.gov/Publications/osha3150.pdf

Concrete and Masonry Construction

OSHA Publication 3106 (Revised 1998), 414 KBPDF, 32 pages.Details information on OSHA’s Concrete andMasonry standard.http://www.osha.gov/Publications/osha3106.pdf

Crystalline Silica Exposure Card for Construction

OSHA Publication 3177 (Revised 2002), 2 pages. Discusses silica hazards, and what employersand employees can do to protect against expo-sures to silica.A Spanish version is also available. OSHAPublication 3179 (Revised 2003), 2 pages.

Excavations

OSHA Publication 2226 (Revised 2002), 533 KBPDF, 44 pages. A detailed explanation of all aspects of excava-tion and trenching.http://www.osha.gov/Publications/osha2226.pdf

Fall Protection in Construction

OSHA Publication 3146 (Revised 1998), 177 KBPDF, 43 pages.http://www.osha.gov/Publications/osha3146.pdf

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OSHA Publication 3007 (Revised 1998), 100 KBPDF, 31 pages. Booklet on ground-fault circuit interrupters forsafe use of portable tools.http://www.osha.gov/Publications/osha3007.pdf

Lead in Construction

OSHA Publication 3142 (Revised 2003), 610 KBPDF, 38 pages. Describes hazards and safe work practices con-cerning lead.http://www.osha.gov/Publications/osha3142.pdf

OSHA Assistance for the Residential

Construction Industry

Many OSHA standards apply to residential con-struction for the prevention of possible fatalities.This web page provides information aboutthose standards and the hazards present in resi-dential construction. It was developed in coop-eration with the National Association of HomeBuilders (NAHB) as part of the OSHA-NAHBAlliance.http://www.osha.gov/SLTC/residential/index.html

Selected Construction Regulations (SCOR) for

the Home Building Industry (29 CFR 1926)

OSHA Publication (Revised 1997), 1.2 MB PDF,224 pages.Provides information on safe and healthful workpractices for residential construction employers;identifies OSHA standards applicable to hazardsfound at worksites in the residential construc-tion industry.http://www.osha.gov/Publications/scor1926.pdf

Stairways and Ladders

OSHA Publication 3124 (Revised 2003), 155 KBPDF, 15 pages.Explains OSHA requirements for stairways andladders.http://www.osha.gov/Publications/osha3124.pdf


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Working Safely in Trenches

OSHA Publication 3243 (2005), 2 pages.Provides safety tips for workers in trenches. ASpanish version is on the reverse side.http://www.osha.gov/Publications/trench/trench_safety_tips_card.pdf

Crane SafetySafety and Health Topics: Crane, Derrick and

Hoist Safety -- Hazards and Possible Solutions

December 2003. One page.OSHA website index provides references to aidin identifying crane, derrick and hoist hazards inthe workplace.http://www.osha.gov/SLTC/cranehoistsafety/recognition.html

Electrical HazardsControl of Hazardous Energy (Lockout/Tagout)

OSHA Publication 3120 (Revised 2002), 174 KBPDF, 45 pages.This booklet presents OSHA’s general require-ments for controlling hazardous energy duringservice or maintenance of machines or equipment.http://www.osha.gov/Publications/osha3120.pdf

Controlling Electrical Hazards

OSHA Publication 3075 (Revised 2002), 349 KBPDF, 71 pages.This publication provides an overview of basicelectrical safety on the job.http://www.osha.gov/Publications/osha3075.pdf

Safety and Health Topics: Lockout/Tagout

OSHA website index to information about lock-out/tagout, including hazard recognition, com-pliance, standards and directives, ReviewCommission and Administrative Law JudgeDecisions, standard interpretations and compli-ance letters, compliance assistance and training.http://www.osha.gov/SLTC/controlhazardousenergy/index.html

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Hazard CommunicationHazard Communication: Foundation of

Workplace Chemical Safety Programs

OSHA website index for resources on hazardcommunication.http://www.osha.gov/SLTC/hazardcommunica-tions/index.html

Frequently Asked Questions for Hazard

Communication

OSHA, 6 pages.Website questions and answers on hazard com-munication.http://www.osha.gov/html/faq-hazcom.html

Hazard Communication Standard

OSHA Fact Sheet No. 93-26 (1993), 3 pages. Highlights protections under OSHA’s HazardCommunication standard.http://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=FACT_SHEETS&p_id=151

Hazard Communication Guidelines for

Compliance

OSHA Publication 3111 (2000), 112 KB PDF, 33pages.This document aids employers in understand-ing the Hazard Communication standard and inimplementing a hazard communication pro-gram.http://www.osha.gov/Publications/osha3111.pdf

Chemical Hazard Communication

OSHA Publication 3084 (1998), 248 KB PDF, 31pages. This booklet answers several basic questionsabout chemical hazard communication.http://www.osha.gov/Publications/osha3084.pdf

NIOSH Pocket Guide to Chemical Hazards

Handy source of general industrial hygieneinformation on several hundred chemicals/class-es for workers, employers and occupationalhealth professionals.http://www.cdc.gov/niosh/npg/npg.html



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Material HandlingMaterials Handling and Storage

OSHA Publication 2236 (Revised 2002), 559 KBPDF, 40 pages.A comprehensive guide to hazards and safework practices in handling materials.http://www.osha.gov/Publications/osha2236.pdf

Personal Protective EquipmentPersonal Protective Equipment

OSHA Publication 3155 (2003), 305 KB PDF, 44pages.Discusses equipment most commonly used forprotection for the head, including eyes and faceand the torso, arms, hands, and feet. The use ofequipment to protect against life-threateninghazards is also discussed.http://www.osha.gov/Publications/OSHA3155/osha3155.html

Safety and Health Topics: Personal Protective

Equipment

OSHA website index to hazard recognition, con-trol and training related to personal protectiveequipment. http://www.osha.gov/SLTC/personalprotectiveequipment/index.html

Toxic Metals: CadmiumSafety and Health Topics: Cadmium

OSHA website index to recognition, evaluation,control, compliance and training related toCadmium.http://www.osha.gov/SLTC/cadmium/index.html

Electronic ConstructionResources

OSHA eTools and Expert Advisors can be found

on OSHA’s website: http://www.osha.gov

eToolsConstruction: Preventing Fatalities. Constructioncan be a safe occupation when workers areaware of the hazards, and an effective safety

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and health program is used. This eTool will helpworkers identify and control the hazards thatcommonly cause the most serious constructioninjuries. A Spanish translation of this eTool isalso available.

Scaffolding: Supported Scaffolds and Suspended

Scaffolds. These eTools provide illustrated exam-ples of safe scaffolding use. Hazards are identi-fied as well as the controls that keep those haz-ards from becoming tragedies.

Solutions for Electrical Contractors. This eTooldescribes common hazards that electrical contrac-tors may encounter and possible solutions forthese hazards. The eTool was developed in coop-eration with the Independent Electrical Contract-ors (IEC) as part of the OSHA-IEC Alliance.

Steel Erection. America's 56,000 steel erectorssuffer 35 fatal accidents per year, a rate of onedeath per 1,600 workers. OSHA estimates that30 of those deaths as well as nearly 1,150 annu-al lost-workday injuries can be averted by com-pliance with provisions of the Steel Erectionstandard, developed with industry and laborthrough negotiated rulemaking. To that end, thiseTool has been created to educate employersand workers.

OSHA’s Expert AdvisorsThe Asbestos Advisor: This computer programprovides an introduction to the scope and logicof the regulations for general industry, construc-tion and maritime.

Lead in Construction Advisor: This computerprogram provides an introduction to the scopeand logic of the regulations regarding occupa-tional exposure to lead and summary guidanceto facilitate compliance.



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Construction IndustryCooperative and State

Programs

Voluntary Protection ProgramsOSHA recognizes Voluntary Protection Programs(VPP) worksites for their excellent safety andhealth management systems.

OSHA ConstructionOSHA has announced an OSHA Constructionprogram to address the unique needs of theindustry. The goal of this program is to makeVPP more accessible to construction employers,especially small construction employers and tomaintain the high standards of VPP while ex-panding participation to broad constructionindustry categories such as short-term projects,mobile workforces, general contractors and sub-contractors. Pilot programs in these categorieshave shown beneficial results for participants.

OSHA ChallengeOSHA has created the Challenge Pilot to pro-vide greater opportunities to eligible employersinterested in working with OSHA to create saferand healthier workplaces. The pilot is designedto reach and guide employers and companies in all major industry groups who are stronglycommitted to improving their safety and healthmanagement systems and interested in pursu-ing recognition in VPP. OSHA Challenge pro-vides participants a guide or roadmap to

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improve performance and ultimately the oppor-tunity to take part in the VPP Merit or Star pro-grams.

Alliance ProgramAlliances enable organizations committed toworkplace safety and health to collaborate withOSHA to prevent injuries and illnesses in theworkplace.

OSHA has a number of national and regional orarea office alliances that impact the constructionindustries. The details of these alliances can befound on www.osha.gov under Alliances.

OSHA Strategic Partnership Program

Partnerships are voluntary, cooperative relation-ships between OSHA and groups of employers,employees and employee representatives(sometimes including other stakeholders andsometimes involving only one employer) thatencourage, assist and recognize efforts to elimi-nate serious hazards and achieve a high level ofworker safety and health. National constructionpartnerships include AMEC Construction,Associated Builders and Contractors (ABC) andthe National Ready-Mixed Concrete Association.In addition to the national partnerships, OSHA

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has had nearly 170 regional strategic partner-ships with the construction industry since theprogram’s start in 1998.

State ProgramsTwenty-six States and territories operate theirown occupational safety and health programsunder plans approved by Federal OSHA. Twenty-two of these programs cover both private sectorand public (State and local government)employees; four cover public employees only.States may have somewhat different require-ments and procedures for the constructionindustry, but they are required to be at least aseffective as Federal OSHA. All State Plans offer a VPP program and have additional cooperativeprograms parallel to OSHA’s Alliance andStrategic Partnership programs. A list of Stateswith approved plans may be found atwww.osha.gov

ConsultationEvery state offers a free, on-site consultationprogram to help small employers find and fixhazards and establish effective safety and healthmanagement systems. Funded primarily byOSHA, consultation is provided at no cost tosmall employers and is delivered by stateauthorities through professional safety andhealth consultants. More information onOSHA’s Consultation Program appears on theagency’s website at www.osha.gov

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Success Stories Partnership Reduced Injuries

during Art MuseumRenovation

In 2002, OSHA and AMEC Construction devel-oped a partnership to prevent injuries at the$425 million rebuilding/renovation constructionproject for New York City’s renowned Museumof Modern Art (MoMA).

The partnership covered some 220 employeesand 17 employers who worked to more thandouble MoMA’s space and expand facilities forspecial exhibitions, public programs, education-al outreach and scholarly research.

AMEC employees completed more than 800,000hours in 2003 and racked up two impressivesafety and health statistics: the number of DaysAway Restricted and Transferred (DART) percent-age was 90 percent below the national averagefor their standard industrial classification (SIC)code and the Total Case Incident Rate (TCIR)



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was 92 percent below the national average fortheir SIC.

Best practices used included daily safety inspec-tions conducted at the site and any hazardsidentified were corrected immediately. Inspec-tion results were discussed at safety committeemeetings. Each employee knew that a safetyissue would be dealt with promptly when itcame to management’s attention. Additionally,an on-site incentive encouraged safe workplacepractices.

The right combination of best safety manage-ment practices, partnering between OSHA andAMEC Construction, and a DART percentage 90percent below the national average are fittingachievements for a new and better home for theworld’s leading collection of modern and con-temporary art.

Fatalities Prevented, InjuriesMinor, Workers’ Comp

Costs Slashed

Turner Construction and OSHA TeamedUp on Wisconsin Stadium Project

Teamwork at the Green Bay Packers’ LambeauField is not just for professional football players.A partnership between Turner Construction andOSHA made teamwork in achieving health andsafety a top priority for construction workersbuilding and expanding the stadium.

In 2003, the $295 million renovation of theLambeau Field stadium was completed, morethan doubling the size of the previous stadium.Seating capacity was increased from 60,890 toover 72,000.

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Partnering with OSHA paid off. There werefewer serious injuries for workers and a morethan 20 percent cut in workers’ compensationcosts for the contractor.

The partnership had three goals:

• All contractors have an effective safety andhealth program;

• All hazards corrected daily after daily auditsare conducted; and

• Increase the level of training for supervisorsand employees.

The work was more hazardous than typical steelerections because stadiums are curved andangular in shape. Also, construction and demoli-tion activities were taking place simultaneously,often within a few feet of each other.

Several potential serious accidents were avoid-ed by requiring all contractors’ safety and healthprograms to establish a requirement of 100 per-cent fall protection at or above six feet.

One worker on the project slipped off a steelbeam located six stories above ground. Thanksto his use of full fall protection, serious injury --or possible death -- was avoided. He was back atwork shortly after his rescue. Less than twomonths later, a second worker slipped from abeam, but also escaped injury because of hisfall protection equipment. Like his coworker, hereturned to work the same day. An ironworkerand a carpenter also fell and were saved bytheir harnesses.

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A significant achievement included 4,300 work-ers completing OSHA’s 10-hour constructiontraining. An added benefit for the industry isthat these employees are bringing their safetytraining to other sites where they are now work-ing.

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Occupational Safety and Health AdministrationU.S. Department of Labor

www.osha.gov

Employers are responsible for providing asafe and healthful workplace for theiremployees. OSHA’s role is to assure thesafety and health of America’s workers bysetting and enforcing standards; providingtraining, outreach and education; establish-ing partnerships; and encouraging continu-al improvement in workplace safety andhealth.

This informational booklet provides a gen-eral overview of a particular topic related toOSHA standards. It does not alter or deter-mine compliance responsibilities in OSHAstandards or the Occupational Safety andHealth Act of 1970. Because interpretationsand enforcement policy may change overtime, you should consult current OSHAadministrative interpretations and decisionsby the Occupational Safety and HealthReview Commission and the Courts foradditional guidance on OSHA compliancerequirements.

This publication is in the public domain andmay be reproduced, fully or partially, with-out permission. Source credit is requestedbut not required.

This information is available to sensoryimpaired individuals upon request. Voicephone: (202) 693-1999; teletypewriter (TTY)number: (877) 889-5627.

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and follow the rules set out in the NEC andthe manufacturer’s installation guides wheninstalling cables in cable trays.

Hazards associated with overloaded cable traysOverfilling and improperly securing wires incable trays can lead to a number of serioushazards. Weight is one issue; all cable traysand their associated supports are rated for aspecific maximum weight, based partly on theallowable fill area and the spacing of the cabletray supports. Overloading cable trays canlead to a breakdown of the tray, its connectingpoints, and/or supports, causing hazards topersons underneath the cable tray and evenleading to possible electric shock and arc-flash/blast events from component failurewhen the cables are suddenly no longer sup-ported. Additionally, cables in trays can bedamaged by improperly securing and installingother cables and wires in the same cable tray.

The NEC requirements for cable tray fill alsoconsider the heat buildup in conductors whilecurrent flows. When cable trays are over-loaded, excessive heat buildup in and aroundlive conductors can cause the insulation tobreak down, leading to potential shock haz-ards or fires. Fires can occur either in thecable tray (which may provide a fire path) orin combustible materials near the cable tray.Furthermore, the improper use of flexible cordcould lead to the spread of toxic fumes if a firewere to occur.

Grounding of cable tray systems is essentialfor personal safety and protection against arc-

Cable trays feature flexibility unmatched byconduit, as cables are easier to mark, removeand find in cable trays. Cable trays are avail-able in a number of different configurations,including ladder, ventilated trough, ventilatedchannel, solid bottom, wire mesh, single rail,and other similar structures. They are manu-factured in steel, aluminum, and fiber rein-forced plastic (FRP), although aluminumaccounts for about 70% of the cable trays usedin industry today.

Overloading cable trays Cable trays come in a wide variety of sizes.The appropriate size and number of cable traysdepends directly on the number and size ofconductors intended and the allowable fill areaas specified in the NEC. Also, since cable traysoffer flexibility for modification and expansion,engineers and designers should plan cable traysystems to be sized and designed to anticipateboth current and future needs.

Cable tray fill is addressed in the 2005 editionof NEC Sections 392.8, 392.9, 392.10, and392.12. The type of cable tray (e.g., solid, ven-tilated), ampacity requirements, and the typeand voltage rating of cable used determinesthe allowable fill for each cable tray — ventilat-ed cable trays provide for the greatest allow-able fill due to increased airflow. A genericguideline provided by The Cable Tray Instituteindicates that cable trays should not be filled inexcess of 40-50% of the inside area of the trayor of the maximum weight based on the cabletray specifications. The NEC provides specificand more detailed requirements for cable trayfill. In any case, the best strategy is to review

FactSheetElectrical Safety Hazards of Overloading Cable TraysAccording to the 2005 National Electrical Code® (NEC), a cable tray system is “[a] unit or assembly of units or sections and associated fittings forming a structuralsystem used to securely fasten or support cables and raceways.” Cable trays supportcable across open spans in the same manner that roadway bridges support traffic.Cable trays are not raceways, and are treated as a structural component of a facility’selectrical system. Cable trays are a part of a planned cable management system tosupport, route, protect and provide a pathway for cable systems.

535

ing that can occur anywhere in the wiring sys-tem. Proper grounding must be done beforecables are installed and tested before cablesare energized. In addition to these generalrequirements, metallic cable tray systems sup-porting electrical conductors must be electrical-ly continuous and effectively bonded as per therequirements of the 2005 edition of NECSection 392.7.

Recognizing overloaded cable traysRecognizing overloaded cable trays is not diffi-cult. The fill values for cable trays specified inthe 2005 NEC range from a single layer toroughly a 50% fill of the cross-sectional area ofthe cable tray. If visual observation reveals acable tray that is completely full and/or over-flowing with cables, chances are that the cabletray is in violation of both the National ElectricalCode and OSHA requirements. One of themajor culprits associated with overloaded cabletrays are abandoned cables within the tray.These abandoned cables should be removed;and in fact, section 590.3(D) and various sec-tions in Chapter 8 of the 2005 NEC specificallyrequire removal of abandoned temporarywiring and communication cable installed with-in a cable tray.

Wiring methods permitted in cable traysAny wiring methods used in cable trays mustbe listed by a Nationally Recognized TestingLaboratory as suitable for use in cable traysand in the environment in which it is installed.Table 392.3(A) of the NEC and OSHA’s 1910.305(a)(3)(i) provide corresponding lists of conductorsand raceways permitted in cable tray systems.Additionally, NEC Section 392.3(B) and OSHA’s1910.305(a)(3)(i)(B) allow other specific conduc-tors in industrial establishments where mainte-nance and supervision assure that only quali-fied persons will service the cable tray sys-tems. Flexible cords are not currently listed

This is one in a series of informational fact sheets highlighting OSHA programs, policies or

standards. It does not impose any new compliance requirements. For a comprehensive list of

compliance requirements of OSHA standards or regulations, refer to Title 29 of the Code of Federal

Regulations. This information will be made available to sensory impaired individuals upon request.

The voice phone is (202) 693-1999; teletypewriter (TTY) number: (877) 889-5627.

for use in cable trays (NEC Article 400, OSHA,1910.305(g)) as they are prohibited as areplacement for the fixed wiring of a structure.The insulation on flexible cords can breakdown and become brittle over the years, whichcan lead to shorts and fires containing toxicfumes.

Standards and regulations that apply tocable traysCable trays were first covered in the 1965 edi-tion of the NEC, under Continuous Rigid CableSupports. Today, the use and installation ofcable trays is covered by Article 392 of theNEC, and by OSHA regulations in 29 CFR1910.305(a)(3) and 1910.399, or comparablestandards promulgated by States operatingOSHA-approved State plans. Specific permit-ted uses of cable trays are covered by the 2005edition of NEC Section 392.3 and OSHA’s1910.305(a)(3)(i); uses not permitted areaddressed in NEC 392.4 and OSHA’s1910.305(a)(3)(ii). Other sections and articles ofthe NEC are referenced throughout Article 392for specific installation and use issues. TheNational Electrical Manufacturers Association(NEMA) also publishes three standards thatapply to the proper manufacture and installa-tion of cable trays: ANSI/NEMA-VE 1-1998,Metal Cable Tray Systems; NEMA-VE 2-1996,Metal Cable Tray Installation Guidelines; andNEMA-FG-1998, Nonmetallic Cable TraySystems.

For more informationNational Electrical Code®, (2005 Edition) Article392 (See also NEC Handbook).

OSHA 29 CFR 1910.305(a)(3) and 1910.399.

Cable Tray Institute (http://www.cabletrays.com).

The Cable Tray Manufacturer’s Installation andUse Instructions.


www.osha.gov(800) 321-OSHA

For more complete information:

DSTM 03/2006

536

Rules to live by• Do NOT assume that a downed conductor

is safe simply because it is on the groundor it is not sparking.

• Do NOT assume that all coated, weather-proof or insulated wire is just telephone,television or fiber-optic cable.

• Low-hanging wires still have voltage poten-tial even if they are not touching the ground.So, “don’t touch them.” Everything is ener-gized until tested to be de-energized.

• Never go near a downed or fallen electricpower line. Always assume that it is ener-gized. Touching it could be fatal.

• Electricity can spread outward through theground in a circular shape from the pointof contact. As you move away from thecenter, large differences in voltages can becreated.

• Never drive over downed power lines.Assume that they are energized. And, evenif they are not, downed lines can becomeentangled in your equipment or vehicle.

• If contact is made with an energized powerline while you are in a vehicle, remain calmand do not get out unless the vehicle is onfire. If possible, call for help.

• If you must exit any equipment because offire or other safety reasons, try to jumpcompletely clear, making sure that you donot touch the equipment and the ground atthe same time. Land with both feet togeth-er and shuffle away in small steps to mini-mize the path of electric current and avoidelectrical shock. Be careful to maintain yourbalance.

Safety FirstAbove all else, always consider all equipment,lines and conductors to be energized. Becautious and if you notice downed wires ordamaged electrical equipment, contactappropriate utility personnel. Rememberthat circuits do not always turn off when apower line falls into a tree or onto theground. Even if they are not sparking orhumming, fallen power lines can kill you ifyou touch them or even the ground nearby.

EnergyDowned wires can energize other objects,including fences, water pipes, bushes andtrees, buildings, telephone/CATV/fiber opticcables and other electric utilities. Even man-hole castings and reinforcement bars (re/bar)in pavement can become energized bydowned wires. During storms, wind-blownobjects such as canopies, aluminum roofs,siding, sheds, etc., can also be energized bydowned wires.

BackfeedWhen electrical conductors are inadvertentlyenergized by other energy sources, backfeedoccurs. Some of those sources include:• Circuit ties/switch points• Lightning• Generators• Downstream events

Simply testing for energy sources is not suf-ficient since hazardous electrical events canhappen without warning. Ensure that properlockout/tagout procedures are always fol-lowed.

FactSheetWorking Safely Around Downed Electrical WiresElectrical hazards exist in some form in nearly all occupations. However, those hazards multiply for workers involved in cleanup and recovery efforts followingmajor disasters and weather emergencies. One particular life-threatening dangerexists around downed and low-hanging electrical wires.

537

This is one in a series of informational fact sheets highlighting OSHA programs, policies or

standards. It does not impose any new compliance requirements. For a comprehensive list of

compliance requirements of OSHA standards or regulations, refer to Title 29 of the Code of Federal

Regulations. This information will be made available to sensory impaired individuals upon request.

The voice phone is (202) 693-1999; teletypewriter (TTY) number: (877) 889-5627.


www.osha.gov(800) 321-OSHA

For more complete information:

DOC 7/2005

538

MJC – TECH ED – ELECTRONICS

.

ELTEC/INTEC 320 - Electrical Safety – QUIZ #1

Student name:_____________________________

1. The American National Institute writes its own standards T __ F __ (1 point)

2. The actions of people account for what percentage of incidents that result in injury?

A. 25% __ B. 50% __ C. 75% __ D. 100% __ (1 point)

3. Which of the following is the National Electrical Code? (1 point)

A. NFPA70 __ B. NFPA70B __ C. NFPA70E __ D. NFPA73

4. Compliance with the NEC® is all that is required to assure a safe and dependable

system T __ F ___ (1 point)

5. OSHA violations can result in jail time for employers. T __ F __ (1 point)

6. NFPA70E suggest the following (1 point)

a. Electrical hazard include shock, arc-flash, and arc-blast

b. The best way to avoid injury or incident is to establish an electrically safe

work condition.

c. Procedures and training are extremely important if injury is to be avoided

d. All of the above.

7. Which standard covers “electrical equipment maintenance”? (1 point)

A. NFPA79 __ B. IEC947-4-1 __ C. NESC __ D. NFPA70B __

8. Training records should be kept for legal reasons. T. __ F. __ (1 point)

9. Summarize direct and indirect costs associated with incidents or injuries. (5 points)

539

10. Summarize OSHA 1910 Subpart S – 1910.334; 1910.335 and OSHA 1926 Subpart

K 1926.416; 1926.417 (1926 standards are provided in the last pages of this quiz)

(10 points)

11. From the selection of Standard Interpretations – page 291

In the case of a nursing home cited for the failure of providing a ground for

equipment connected by cord and plug: Why OSHA did not allow the

installation of ground fault circuit interrupter (GFCI) receptacles, in lieu of an

expensive system grounding rewiring? (10 points)

Based on these interpretation letters: Is there a contradiction between the OSHA

requirements and the NEC previsions regarding to the use of GFCI protection

and grounding systems? Answer yes or no and justify your answer. (15 points)

540

OSHA 1926 Subpart K – Electrical

Safety and Health Regulations for Construction

§ 1926.416 General requirements.

(a) Protection of employees

(1) No employer shall permit an employee to work in such proximity to any part

of an electric power circuit that the employee could contact the electric power circuit

in the course of work, unless the employee is protected against electric shock by de-

energizing the circuit and grounding it or by guarding it effectively by insulation or

other means.

(2) In work areas where the exact location of underground electric powerlines is

unknown, employees using jack-hammers, bars, or other hand tools which may

contact a line shall be provided with insulated protective gloves.

(3) Before work is begun the employer shall ascertain by inquiry or direct

observation, or by instruments, whether any part of an energized electric power

circuit, exposed or concealed, is so located that the performance of the work may

bring any person, tool, or machine into physical or electrical contact with the electric

power circuit. The employer shall post and maintain proper warning signs where such

a circuit exists. The employer shall advise employees of the location of such lines,

the hazards involved, and the protective measures to be taken.

(b) Passageways and open spaces

(1) Barriers or other means of guarding shall be provided to ensure that

workspace for electrical equipment will not be used as a passageway during periods

when energized parts of electrical equipment are exposed.

(2) Working spaces, walkways, and similar locations shall be kept clear of cords

so as not to create a hazard to employees.

(c) Load ratings. In existing installations, no changes in circuit protection shall be made

to increase the load in excess of the load rating of the circuit wiring.

(d) Fuses. When fuses are installed or removed with one or both terminals energized,

special tools insulated for the voltage shall be used.

(e) Cords and cables.

(1) Worn or frayed electric cords or cables shall not be used.

541

(2) Extension cords shall not be fastened with staples, hung from nails, or

suspended by wire.

§ 1926.417 Lockout and tagging of circuits.

(a) Controls. Controls that are to be deactivated during the course of work on energized

or de-energized equipment or circuits be tagged.

(b) Equipment and circuits. Equipment or circuits that are de-energized shall be rendered

inoperative and shall have tags attached at all points where such equipment or circuits can

be energized.

(c) Tags. Tags shall be placed to identify plainly the equipment or circuits being worked

on.

§ 1926.431 Maintenance of equipment.

The employer shall ensure that all wiring components and utilization equipment in

hazardous locations are maintained in a dust-tight, dust-ignition-proof, or explosion-proof

condition, as appropriate. There shall be no loose or missing screws, gaskets, threaded

connections, seals, or other impairments to a tight condition.

§ 1926.432 Environmental deterioration of equipment.

(a) Deteriorating agents

(1) Unless identified for use in the operating environment, no conductors or

equipment shall be located:

(i) In damp or wet locations;

(ii) Where exposed to gases, fumes, vapors, liquids, or other agents

having a deteriorating effect on the conductors or equipment; or

(iii) Where exposed to excessive temperatures.

(2) Control equipment, utilization equipment, and busways approved for use in

dry locations only shall be protected against damage from the weather during

building construction.

(b) Protection against corrosion. Metal raceways, cable armor, boxes, cable sheathing,

cabinets, elbows, couplings, fittings, supports, and support hardware shall be of materials

appropriate for the environment in which they are to be installed.

542

MJC – TECH ED – ELECTRONICS Dptm

.


Student name:_____________________________

1. In OSHA’s generic overview “CONTROLLING ELECTRICAL HAZARDS” three

types of burns are described: Electrical burns, arc or flash burns, and thermal contact

burns. According to the OSHA’s text: What circumstances can cause each of them? (3

points)

Type of burn Caused by

Electrical burn

Arc or Flash burn

Thermal contact burn

2. In OSHA’s generic overview “CONTROLLING ELECTRICAL HAZARDS” there

are descriptions of the effects of electrical shocks in muscles (contractions, spasms).

Which hazards do involve these conditions? (2 points)

Based on OSHA text, complete the idea in the first column and describe the possible

consequences of these situations in the second column

When due to an electric shock muscles

contract, such as the case of forcing hand

gripping, the person is unable to…

When due to an electrical shock muscles

contract producing violent spasms the

person might…

543

From Bussmann’s “Safety BASICs”

3. Every employee working with electricity should be train in CPR. T. � ; F. �

(1 point)

4. Of those people who were electrocuted on low-voltage systems (600V or bellow),

approximately what percentage were working on energized equipment? A. 25% B.

50% C. 75% D. 100% (1 point)

5. In an electrical incident, what happens when the skin is broken? (1 point)

a. The body’s resistance goes down, exposing the body to greater current.

b. The body’s resistance goes down, exposing the body to less current.

c. The body’s resistance goes up, exposing the body to greater current.

d. The body’s resistance goes up, exposing the body to less current

6. The “let-go” threshold refers to which of the following? (1 point)

a. The amount of current that causes the hand to let-go of an energized part

b. The amount of voltage that causes the hand to let-go of an energized part

c. The amount of current that causes the hand to be unable to let-go of an energized part

d. The amount of voltage that causes the hand to be unable to let-go of an energized part

7. Tissue and organs can burn at currents of 1.5 amps. A. T. � , B. F. � (1 point)

544

8. The temperature at the terminal of an arc can reach which of the following? (1 point)

a. ½ of the temperature of the surface of the sun.

b. The temperature of the surface of the sun.

c. Almost twice the temperature of the surface of the sun.

d. Almost four times the temperature of the surface of the sun

9. Skin exposed to a temperature of 200ºF for one second will be unhurt. (1point)

A. T � , B. F �

10. When it vaporizes, copper expands by a factor of which of the following? (1 point)

a. 1,670 times

b. 67,000 times

c. 167,000 times

d. None of the above.

11. What are the objectives a ESP should fulfill. (15 points)

545

12. List ESP principles (5 points)

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From Sections #1, #2, #3, and #4 of NIOSH’s “ELECTRICAL SAFETY Student –

Manual”

13. List 5 basic preventive actions that employers and employees should perform to avoid

electrical incidents or minimize their consequences (fifteen mentioned along the text –

Please read the WHOLE text.) – (10 points)

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546

14. What type of extinguishers can be used to put out an electrical fire? (2 points)

15. What are the three stages of a Worker’s Safety Model? Briefly describe them.

(15 POINTS)

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547

548


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Student name:_____________________________

Based on NIOSH’s “ELECTRICAL SAFETY – Student Manual” sections 5 and 6, complete and

answer the next items and questions.

1. What were the OSHA requirements that could have saved the electrician’s life in the study

case of the lighting metal pole incident? (3 points)

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2. What id the inherent risk (hazard) of under size (inadequate) wiring? (1 point)

a. Fire

b. Electromagnetic interference

c. Reduction of the system efficiency due to voltage drop

3. What is the leading cause of today electrical incidents with power lines? (1 point)

a. Failure to comply with appropriate Personal Protective Equipment

b. Failure to comply with measurement procedures

c. Failure to maintain electric shock boundaries (proper work distances)

4. What is the estimated minimum clearance to work close to a 75KV (75000 V) line? Be careful

with estimations; minimum clearances are established by the local AHJ (3 points)

a. 10 feet

b. 132 inches

c. 96 inches

5. What is the most common OSHA electrical violation? (1 point)

a. Lack of compliance with training records

b. Misunderstanding of Lock out tag out procedures

c. Improper grounding in systems and equipment

549

6. In order to withstand the inrush currents produced by the motors’ starting transients, CBs and

fuses are oversized respect of the motor’s FLA (full load amps). As a consequence the

downstream wiring results undersized. The problem is easily solved by connecting an

overload relay before the motor. What hazard results from oversize the relay current setting?

(5 points)

7. Wet condition hazards occur only when the room’s floor, where the equipment or installed

components are, is flooded with water or other conductive liquids, even if it is just a thin

layer of running liquid in the floor’s surface. (2 points)

a. True

b. False

8. List the worksite electrical hazards an electrician might face in daily bases (9 points)

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550

9. List non-electrical hazards associated with the worksite that electricians might face daily. (7

points)

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10. List the clues that are indicating an electrical hazard (7 points)

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551

11. Scan titles though OSHA’s Worker Safety Series Pocket Guide - Construction looking for

electrical hazard related tips. Select five titles – except Electrical Safety – and group them in

the next chart (10 points)

Title Recommendation

Example

Scaffolding Scaffolds are not erected or moved within 10 feet of power lines

552

12. From OSHA’s Worker Safety Series Pocket Guide under Electrical safety (page 515) - What

are the recommendations to follow with power cords. (6 points)

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553

554


.


Student name:_____________________________

1. Based on OSHA’s generic overview “CONTROLLING ELECTRICAL HAZARDS” -

What are the functions of circuit protection devices? (3 points)

2. What do fuses and circuit breakers do and how do they do it? (4 points)

3. What are the purpose of fuses and circuit breakers? Are they designed to protect electrical

devices and systems or to protect persons from electric shock? (2 points)

4. What does a Ground Fault Circuit Interrupter (GFCI) do? How does it work? How fast can it

perform its task? How sensitive a standard GFCI should be? (6 points)

5. What type of protection does provide an Arc-Fault Circuit Interrupters (AFCI)? Would an

AFCI protect an electrician from an arc-flash incident working in a panel? (4 points)

555

From Bussmann’s Safety BASICs section VI

6. Which conditions will determine the survivability of a worker exposed to and arc-flash

incident? (6 points)

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7. Limiting the amount of energy that a flash can release depends on two characteristics of the

overcurrent protective device (OCP – fuses, circuit breakers). Which characteristics are

these? (4 points)

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8. How many seconds take to produce an incurable burn at 205 ºF or over? (1 point)

a. Between 0.5 and 1 second

b. Over 1 seconds

c. 0.1 second or less

9. In the staged arc-flash tests, the sound levels due to the explosive shock waves have

surpassed the 100 dB in all cases. What is the maximum safe sound level after which ear

protection is required? (2 points)

10. In the staged arc-flash tests, the non-current limiting device did allow the release of an

important amount of destructive energy. At chest level the wave shock reached levels over

2160 lbs/sqft. According to the thresholds for injury to humans – Was it enough to produce

serious lung damage if a human were exposed to the flash blast? (1 point)

a. No

b. Almost

c. Yes

556


.


Student name:_____________________________

From OSHA’s Small Business Handbook – “Starting a Safety and Health Management

System”

1) If the owner of an establishment can not personally manage the safety and health

system, then he/she has to select somebody to do it. Does this transference of

management responsibilities transfer the legal responsibilities? In other words, who is

the ultimate responsible for safety and health in the workplace? (2 points)

2) List what key elements have to be taken on account in regard to the electrical system

safety – please refer to the Self-inspection Scope - ELECTRICAL. (7 points)

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557

3) Based on the self-inspection checklist “Medical Services and First Aid”. What are

the provisions for hepatitis B vaccination for employees who render first aid only as

a collateral duty and might not have been offered pre-exposure hepatitis B vaccine?

(9 points)

1.

2.

3.

4.

From Bussmann’s “Safety BASICs” – VII and VIII

4) Facilities should know, before an electrical incident ever occurs, which medical

facilities specializes in electrical trauma (1 point)

a) T.

b) F.

5) When coming to the aid of an electrical incident victim, which of the following is the

first action the rescuer should perform? (1 point)

a) Call OSHA

b) Treat for shock and apply first aid

c) Make sure the power is OFF

558

6) If the victim’s pulse or breathing has stopped, in what length of time can brain

damage occur? (1 point)

a) One minute

b) Four to six minutes

c) Eight to ten minutes

7) Who must to provide a safe workplace? (1 point)

a) Employers

b) Employees

c) Both

8) Who is responsible for implementing the safety program and procedures?

(1 point)

a) Employers

b) Employees

9) Summarize practical steps to be taken in case of electrical incident occurs

(4 points)

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10) List those measures to be taken on account when providing first aid to an electric

incident victim. (7 points)

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559

From the information contained on OSHA’s Medical services and first aid article

1910.151 and the standard interpretation (provided at the end of this quiz)

11) What is the OSHA requirement for NOT HAVING a person or persons trained to

handle an electrical incident “on-site” (5 points)

12) What provisions must be taken when employees may be exposed to injurious

corrosive materials? (5 points)

13) What standard establishes the basic contents of a generic first aid kit? (1 point)

From your own research

14) What health facility in Modesto area that specializes in electrical related traumas?

(1 point)

15) What is the class MJC offer to train in CPR? (2 points)

560

Medical services and first aid. - 1910.151

• Part Number: 1910 • Part Title: Occupational Safety and Health Standards • Subpart: K

• Subpart Title: Medical and First Aid • Standard Number: 1910.151 • Title: Medical services and first aid.

• Appendix: A

1910.151(a)

The employer shall ensure the ready availability of medical personnel for advice and

consultation on matters of plant health.

1910.151(b)

In the absence of an infirmary, clinic, or hospital in near proximity to the workplace which is

used for the treatment of all injured employees, a person or persons shall be adequately

trained to render first aid. Adequate first aid supplies shall be readily available.

1910.151(c)

Where the eyes or body of any person may be exposed to injurious corrosive materials,

suitable facilities for quick drenching or flushing of the eyes and body shall be provided

within the work area for immediate emergency use.

561

Appendix A to § 1910.151 -- First aid kits (Non-Mandatory) -

1910.151 App A

• Part Number: 1910 • Part Title: Occupational Safety and Health Standards • Subpart: K • Subpart Title: Medical and First Aid • Standard Number: 1910.151 App A • Title: Appendix A to § 1910.151 -- First aid kits (Non-Mandatory)

Appendix A to § 1910.151 -- First aid kits (Non-Mandatory)

First aid supplies are required to be readily available under paragraph § 1910.151(b). An example of the minimal contents of a generic first aid kit is described in American National Standard (ANSI) Z308.1-1998 "Minimum Requirements for Workplace First-aid Kits." The contents of the kit listed in the ANSI standard should be adequate for small worksites. When larger operations or multiple operations are being conducted at the same location, employers should determine the need for additional first aid kits at the worksite, additional types of first aid equipment and supplies and additional quantities and types of supplies and equipment in

the first aid kits. In a similar fashion, employers who have unique or changing first-aid needs in their workplace may need to enhance their first-aid kits. The employer can use the OSHA 200 log, OSHA 101's or other reports to identify these unique problems. Consultation from the local fire/rescue department, appropriate medical professional, or local emergency room may be helpful to employers in these circumstances. By assessing the specific needs of their workplace, employers can ensure that reasonably anticipated supplies are available. Employers should assess the specific needs of their worksite periodically and augment the first aid kit appropriately.

If it is reasonably anticipated that employees will be exposed to blood or other potentially infectious materials while using first aid supplies, employers are required to provide appropriate personal protective equipment (PPE) in compliance with the provisions of the Occupational Exposure to Blood borne Pathogens standard, § 1910.1030(d)(3) (56 FR 64175). This standard lists appropriate PPE for this type of exposure, such as gloves, gowns, face shields, masks, and eye protection. [63 FR 33450, June 18, 1998; 70 FR 1141, Jan. 5, 2005]

562


03/23/2007 - Clarification of "in near proximity" and OSHA's

discretion in enforcing first aid requirements in particular cases.

• Standard Number: 1910.151; 1910.151(b); 1910.266; 1910.266(i)(7); 1910.269; 1910.269(b); 1926.50; 1926.50(c)

This letter constitutes OSHA's interpretation only of the requirements discussed and may not be applicable to any situation not delineated within the original correspondence.

March 23, 2007 Mr. Brian F. Bisland 33 West Old Farm Road Hopewell Junction, New York 12533 Dear Mr. Bisland:

This is in response to your July 5, 2006 letter to the Occupational Safety and Health's Administration's (OSHA) Correspondence Control Unit, in which you requested an interpretation of "in near proximity" for 29 CFR 1910.151(b). Paragraph 1910.151(b) of OSHA's general industry standard on medical services and first aid states, "In the absence of an infirmary, clinic, or hospital in near proximity to the workplace which is used for the treatment of all injured employees, a person or persons shall be adequately trained to render first aid. Adequate first aid supplies shall be readily available." The OSHA construction standard at 29 CFR 1926.50(c) has a similar requirement.

OSHA stated in a letter of interpretation dated January 16, 2007 to Mr. Charles F. Brogan: "The primary requirement addressed by these first aid standards is that an employer must ensure prompt first aid treatment for injured employees, either by providing for the availability of a trained first aid provider at the worksite, or by ensuring that emergency treatment services are within reasonable proximity of the worksite." The employer must ensure that ". . . adequate first aid is available in the critical minutes between the occurrence of an injury and the availability of physician or hospital care for the injured employee."

The letter further explains: "While the first standards do not prescribe a number of minutes, OSHA has long interpreted the term 'near proximity' to mean that emergency care must be available within no more than 3-4 minutes from the workplace. Medical literature establishes that, for serious injuries such as those involving stopped breathing, cardiac arrest, or uncontrolled bleeding, first aid treatment must be provided within the first few minutes to avoid permanent medical impairment or death. Accordingly, in workplaces where serious accidents such as those involving falls, suffocation, electrocution, or amputation are possible, emergency medical services must be available within 3-4 minutes, if there is no employee on the site who is trained to render first aid."

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OSHA does exercise discretion in enforcing the first aid requirements in particular cases. For example, OSHA recognizes that in workplaces, such as offices, where the possibility of such serious work-related injuries is less likely, a longer response time of up to 15 minutes may be reasonable.

The January 16, 2007 letter also notes: "Other standards that apply to certain specific hazards or industries make employee first aid training mandatory, and reliance on outside emergency responders is not an allowable alternative. For example, see 29 CFR 1910. 266(i)(7) (mandatory first aid training for logging employees), and 29 CFR 1910.269(b) (requiring persons trained in first aid at work locations in the electric power industry) . . . You may find these standards on OSHA's website, http://www.osha.gov, by following the link to 'standards' and searching for 'first aid'. . .'logging,' etc." Thank you for your interest in occupational safety and health. I have enclosed the aforementioned letter to Mr. Brogan for your reference. We hope you find this information

helpful. OSHA requirements are set by statute, standards, and regulations. Our interpretation letters explain these requirements and how they apply to particular circumstances, but they cannot create additional employer obligations. This letter constitutes OSHA's interpretation of the requirements discussed. Note that our enforcement guidance may be affected by changes to OSHA rules. Also, from time to time we update our guidance in response to new information. To keep apprised of such developments, you can continue to consult OSHA's website, as mentioned above, at http://www.osha.gov. If you have any further questions, please feel free to contact the Office of General Industry

Enforcement at (202) 693-1850. Sincerely, Richard E. Fairfax, Director Directorate of Enforcement Programs

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Student name:_____________________________

These 64 questions try to cover the broad field of Electrical Hazard Control. Hazard

Control is the very reason to study Electrical Safety, and in a way this questions are at the

very heart of this ELTEC/INTEC 320 course. Hopefully four weeks will be dedicated to

the subject focusing practical and management issues; that is a quarter of the total of

classes that conform this course.

In a different way than the questionnaires administrated before, there are not headlines as

reading guides before groups of questions around an issue. The sequence of issues

brought up is interwoven in several texts, although most questions have a direct answer in

one of the texts used to make this quiz.

The “must-read” list is:

• OSHA

� Articles 1910.331 through 335, 1910.147 and 1910.147 Appendix A

� OSHA 3120 - Control of Hazardous Energy

� OSHA 3151-12R - Personal Protective Equipment

� OSHA 3007 - Ground Fault Protection in Construction Sites

• NIOSH – ELECTRICAL SAFETY – Student Manual

� Section 7 and section 8 (all the mentioned study cases come from these

sections)

• Bussmann Safety BASICs

� From IX to X(N)

You also will need

• NFPA 70E Table 130.3 (c) (Bussmann page 26)

• NFPA 70E Table 130.7 (c) (9) (a)

• NFPA 70E Table 130.7 (c) (10)

• Arc-Flash Incident Energy Calculator (Bussmann page 68)

1) In which of the following standards was the concept of an electrically safe work

condition first introduced? (1 point)

a) NFPA 70

b) NFPA 70B

c) NFPA 70E

d) OSHA 1910.147

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2) According to NFPA 70E 120.3(A) – When an electrically safe work condition is

achieved? (3 points)

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Suppose that you are the new Safety and Health manager in your workplace, and your

first task is to establish an energy-control program.

3) Which are the three basic areas such program must cover? (6 points)

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Assuming a small factory where most of the machinery and systems are driven by

electricity within a similar range of energy level and operative sequences, but where

there are a couple of machines that use other sources of energy such as hydraulic or

pneumatic. In summary this factory have three distinctive spheres:

a) Most of the systems and machines,

b) Some equipment that include hydraulic or pneumatic sources, and

c) The plant as a whole

4) What must an energy-control procedure include, and what should be done when there

are coexistence of different energy sources, energy levels and type of devices?

(10 points)

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5) What reference (OSHA article, appendix) an employer can follow as a guide to

establish an energy-control procedure? (4 points)

.

6) When training employees, more than how to lock and tag switches or valves should

be explained What are the three important areas a lockout/tagout training program

should include?

(6 points)

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7) Whose should receive such LOTO training and how often it should be repeated?

(4 points)

8) Identify and list article, sections and subsections into the 1910 standard that regulate

employee training (3 points) and energy-control training, re-training, and training

certification (6 points)

Article. section Title (if apply)

9) How multiple actors, inside workers from different areas, or different shifts, and

outside contractors coordinate their lockout/tagout actions to give continuity to the

energy-control procedure until a maintenance task is completed? (10 points)

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10) Should lockout/tagout procedures be reviewed once are established? If yes, how

often? (4 points)

11) When a LOTO procedure is inspected three facts should be verified. Which are:

(6 points)

a)

b)

c)

12) What is the intended application of 1910.147? (2 points)

13) What is the difference between an “affected employee” and an “authorized

employee”? (4 points)

� Affected employee

� Authorized employee

14) What is the specifically meaning of the term “lockout” (2 points)

15) What is the specifically meaning of the term “tagout” (2 points)

16) Should the LOTO procedures being formally stated in writing? Justify (4 points)

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17) Who must to provide the lock and tag devices? (1 point)

a) The employer

b) The employee

18) Can any lock or any tag being used for LOTO purposes? (1 point)

a) Yes

b) No

19) Tagout must be used unless the employer can demonstrate that the use of a lockout

system can provide full employee protection. (1 point)

a) True

b) False

20) Identify article, sections and subsections into the 1910 standard that regulate the

physical characteristics of the locks and tags. (2 points)

�

21) Identify and list article, sections and subsections into 1910 standard that regulate the

lockout/tagout device application procedure and the lockout/tagout devices removal

procedure. (2 points)


22) In broad terms, what issues are covered for 1910.147(f) – Additional requirements?

(4 points)


569

23) Based specifically on the “Typical minimal lockout procedures – 1910.147 App A”

draft a lockout/tagout, and a lockout/tagout removal step by step sequences.

(18 points)

Lockout/Tagout Removing Lockout/Tagout

24) In the study case of the two electricians working on top of a spray paint booth, the

victim committed several mistakes that result fatal. What steps should have been

followed to avoid this fatality? (9 points)

25) According to OSHA 1910.333(a)(1) – NFPA 130.1, workers shall not work on or

near exposed live parts with two exceptions. Which are these two exceptions?

(4 points)

570

26) Is the process of establishing an “electrical safe work condition” a job performed

under potential electrical hazard? (1 point)

a) Yes

b) No

27) After determining that the circuit is de-energized, it is never necessary to use

grounding straps. (1 point)

A. True

B. False

28) A circuit can shock you even if all external sources of power have been removed

(1 point)

a) True

b) False

29) What are the NEC 2008 – 110.16 (same that 2002 – 110.16) Flash Protection

previsions? (10 points)

30) What are the practical conclusions a Shock Hazard Analysis and a Flash Hazard

Analysis should reach? (12 points)

31) How are classified the approach boundaries for shock protection and what

requirements shall be fulfilled in each of them to comply with safe working practices?

(12 points)

Approach Boundary Requirements

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32) Any person within the prohibited approach boundary must be qualified (1 point)

a) True

b) False

33) NFPA 70E 110.6 (D)(1) provides the training requirements for a qualify person.

Mention three requirements included in the provision. (6 points)

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34) An electrician opens an energized 3 phase panel that feeds a group of offices to

troubleshoot a problem. The panel is rated 208Y/120V, its main breaker is a 250A

MCCB, and its Isc 10350A. One clerk is standing by him expecting to lend a hand in

case of need. The clerk is at 2 feet from the array of circuit breakers. Within what

boundary the clerk is standing on? Where should he been standing if he wants to see

the electrician work? (6 points)

35) Define “Flash Protection Boundary”? (5 points)

36) If you have to perform a quick assessment of a FPB for a 500A circuit with an

available Isc 14000 A, protected by a 500A molded case circuit breaker. How many

inches for the FPB you would recommend? � _______ in (3 points)

Based on the Arc-Flash Incident Energy Calculator, the FPB for this case should be

A) A foot

B) Between 1 foot and 2’ 3”

C) 2’1” or above

37) What is the incident energy level in cal/cm² for the former case? (1 point)

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38) What is the Hazard/Risk category of the next tasks:

(2 point each)

A) Removal of bolted cover to expose bare, energized parts, with 4500 A Isc

available at that point in a 480V/277Y system

Category ______

B) Voltage testing on a MCC, 480V, 14000 A Isc

Category ______

C) Installation of a circuit breaker in a 240V panel board with 4000 A Isc

Category ______

39) What adverse conditions might compromise the insulation of EH safety-toe shoes?

(3 points)

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40) Can nonconductive footwear be used in explosive locations? (1 point)

A) Yes

B) No

41) A generic classification of gloves groups them in four families. List these four generic

groups of gloves. (4 points)

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42) What is the voltage rating of Class 00 gloves? (1 point)

A) 1000V

B) 500V

C) 250V

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43) What three basic safety issues are associated with the task of testing for voltage in

systems of up to 1000V? (6 points)

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�

�

44) According to OSHA 1910.334(b)(2) = NFPA 70E 130.6 (K) after a circuit is

deenergized by a circuit protective device, the circuit ____________ [ a) may, or b)

may not] be manually reenergized ______________[ a)in order to follow the possible

cause that triggered the protective device, or b) until has been determined that the

equipment and circuit can be safely energized] (4 points)

45) Repetitive manual reclosing of circuit breakers or reenergizing circuits through

replacing fuses is… (1 point)

A) Prohibited

B) Allowed under technical supervision

C) Allowed under management responsibility

46) Do GFCIs (portable or installed permanently) protect the worker against a line to line

or a line to neutral shock incident? (1 point)

A) Yes

B) No

47) OSHA ground-fault protection rules and regulations establish two possible solutions

to ground-fault situations. In construction sites employers must provide either

___________________________ or ________________________ (2 points)

48) What is the Assured Equipment Grounding Conductor Program? (5 points)

49) Two tests are required to comply with the Assured Equipment Grounding Conductor

Program. How these tests are performed and what are are their purposes? (8 points)

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50) What is the test schedule to comply with the Assured Equipment Grounding

Conductor Program? (3 points)

51) Is it acceptable the use of GFCIs as a substitute of grounding system in a worksite?

(1 point)

A) Yes

B) No

52) What factors ought to be considered in order to build a safe wiring system (wiring

method + conductor type and size)? (10 points)

53) How circuits overload can be controlled and prevented in an existing facility?

(2 points)

A) Using OCPDs

B) Over sizing wires

C) Redistributing loads

D) A and B

E) A and C

F) B and C

54) What four characteristics ought to be observed when selecting an extension cord for a

job? (4 points)

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575

55) What is a good housekeeping policy an electrician should follow upon completion of

a maintenance or modification task on a control panel? (2 points)

56) What maintenance provisions in NFPA 70E 225.2 and 225.3 are stated for molded-

case circuit breakers. (4 points)

57) In the study case of the 29-year-old maintenance worker killed by poor environmental

conditions and maintenance state of the welder he was about to use. What steps

should have been followed to avoid this fatality? (9 points)

58) Following the Safety Model – stage #3, what steps a worker should follow to create a

safe work environment? (8 points)

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59) Following the Safety Model – stage #3, draft a list of issues to address as a planning

guide. (6 points)

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576

60) What type of ladders is suitable for electrical work? (2 points)

61) What gear provisions (minimum - using FR clothing) should be taken to perform the

removal of fuses on a panel board rated 240V or less? (12 points)

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62) What type of hardhat should be wear to perform electrical work? (3 points)

63) Summarize measures to be taken to control hazards through safe work practices

(6 points)

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577

578


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Student name:_____________________________

1) (10 points)

FLA =

Isc =

2) (10 points)

FLA =

Isc =

3) (10 points)

FLA =

Isc =

579

4) (10 points)

FLA =

Isc =

5) (10 points)

FLA =

Isc =

6) (10 points)

FLA =

Isc =

580

7) (20 points)

f =

M =

Isc sym RMS =

8) (20 points)

f =

M =

Isc sym RMS =

581

9) (20 points)

f =

M =

Isc sym RMS =

582


.

ELTEC/INTEC 320 - Electrical Safety – QUIZ #8 (42 points)

Student name:_____________________________

Because for many students this 320 course is an introductory class into the electrical

field, you might not have had chance to take ELTEC 225 or 223, and maybe you are not

familiar with the technology behind different OCPDs and their proper use.. The ABCs of

OCPDs were exposed during the lecture preceding this activity, and the information that

covers the next questions is mostly laid from Bussmann BASICs VI, X (I) to (EE).

Future courses will deeper the comprehension of the logic that leads the selection of these

important components.

1. What is the maximum allowable product of overcurrent protective device clearing

time and available fault current to use the flash protection boundary of 4 feet from

70E-130.3(A)? (2 points)

a) 50kA

b) 50kA cycles

c) 300kA cycles

d) 5000kA cycles

2. What is the maximum short-circuit current and overcurrent protective device clearing

time that will allow the use of 70E-Table 130.7(C)(9)(a) to determine the hazard risk

category for an MCC? (2 points)

a) 25kA short circuit current available, 0.03 second (2 cycles) fault clearing time

b) 25kA short circuit current available, 0.33 second (20 cycles) fault clearing time

c) 65kA short circuit current available, 0.03 second (2 cycles) fault clearing time

d) 65kA short circuit current available, 0.33 second (20 cycles) fault clearing time

3. For arcing faults within their current-limiting range, current-limiting protective

devices can: (2 points)

a) Limit the magnitude and duration of arcing faults

b) Reduce the flash protection boundary

c) Reduce the incident energy

d) All of the above

4. Which rating provides the greater protection against electrical shock? (1 point)

a) IP1X

b) IP2X

c) IP0X

d) IP3X

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5. Sizing an equipment grounding conductor solely based on Table 250.122 of the 2005

NEC (same than 2002 NEC) ensures an adequate, safe ground return path.

(1 point)

a) True

b) False

6. The use of a disconnecting means at every motor, even where not required,

(1 point)

a) It is a waste of money

b) Creates confusion during an electrical incident

c) Provides a quick means of de-energizing

d) Creates confusion and provides a quick means of de-energizing

7. All current-limiting overcurrent protective devices provide the same level of

protection. (1 point)

a) True

b) False

8. Class RK1 fuses can replace Class H and Class RK5 fuses as a possible means to

improve electrical safety. (1point)

a) True B. False

9. Short-time delay settings on circuit breakers should be used to reduce the arc-flash

hazard. (2 point)

a) True

b) False

10. Arc resistant switchgear can be used to prevent arcing faults. (2 points)

a) True

b) False

11. List Non Limiting OCPDs (4 points)

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12. What is “Type 2 protection” for motor controllers? (5 points)

13. Why it is not recommended to use Short – Time Delay settings in circuit breakers?

(5 points)

14. Why it is recommended to use a Main on a Service Entrance? (3 points)

15. Selective Coordination is (1 point)

a) The act of turn on and off loads in an orderly manner

b) The way a machine sequences its functions

c) The act of isolating a faulted circuit from the remainder of the electrical system

16. How a non-current-limiting protective device such as a standard MCCB could be

retrofitted to behave as a current-limiting system if a short circuit incident occurs?

(6 points)

585

17. MCC come rated at their maximum normal service current. The OCPD protecting the

MCC should be size to the rating of the MCC or the actual load it is providing?

(provisions for future expansion might be needed) (5 points)

586

587

� KNOWLEDGE

� CRAFTMANSHIP

� TENACITY

� INTEGRITY

588