Upload
bilel-markos
View
246
Download
1
Embed Size (px)
Citation preview
8/12/2019 Subcontractor Elec
1/38
Subcontractor Electrical Safety & NFPA 70E
Electrical Safety for Subcontractors andSubcontract Technical Representatives
EFCOG Electrical Safety Task Group
Module 8
8/12/2019 Subcontractor Elec
2/38
EFCOG Electrical Safety Task Group 2
Objective
To provide understanding of electrical safetyrequirements for the Subcontract TechnicalRepresentative and the Subcontractor
To facilitate communications of requirements to thesubcontractorTo serve as an aid in assessing a subcontractorsperformance
8/12/2019 Subcontractor Elec
3/38
EFCOG Electrical Safety Task Group 3
Why is NFPA 70E a subcontractor requirement? DOE Order 440.1A, Worker Protection Management For DOE And Contractor
Employees Requires Implementation OSHA General Duty Clause requires workplace free from recognized hazards.
OSHA has cited General Duty Clause for failure to comply with 70E 10CFR 851 requires compliance with NFPA 70E NFPA 70E, Section 110.4 Multiemployer Relationship
(A) Safe Work Practices. On multiemployer worksites (in all industrysectors), more than one employer may be responsible for hazardousconditions that violate safe work practices.
(B) Outside Personnel (Contractors, etc.) the on-site employer and theoutside employer(s) shall inform each other of existing hazards, personalprotective equipment/clothing requirements, safe work practiceprocedures applicable to the work to be performed.
NFPA 70E, Standard for Electrical Safety in the Workplace
8/12/2019 Subcontractor Elec
4/38
EFCOG Electrical Safety Task Group 4
Can OSHA Cite NFPA 70E?
OSHA regulations are often described as the Shall and NFPA70E as the How for electrical safety in the workplace.
OSHA commonly cites the General Duty Clause and uses NFPA
70E as evidence of compliance
From an OSHA Letter of Interpretation dated July 23, 2003:Industry consensus standards, such as NFPA 70E, can be usedby employers as guides to making the assessments andequipment selections required by the standard. Similarly, inOSHA enforcement actions, they can be used as evidence ofwhether the employer acted reasonably.
8/12/2019 Subcontractor Elec
5/38
EFCOG Electrical Safety Task Group 5
NFPA 70E, Standard for Electrical Safety in the Workplace
How does NFPA 70E differ from the National ElectricCode (NEC)?
NFPA 70E is intended to provide work practices to minimize
the worker from electrical energy when using or working onor near electrical equipment and conductors The NEC is intended to provide a safe electrical installation
so that equipment is safe when operating normally
8/12/2019 Subcontractor Elec
6/38
EFCOG Electrical Safety Task Group 6
NFPA 70E, Standard for Electrical Safety in the Workplace
What work practices does NFPA 70E require? Chapter 1, Safety-Related Work Practices
Article 100, Definitions
Article 110, General Requirements for electrical Safety-RelatedWork Practices
Article 120, Establishing an Electrically Safe Work Condition
Article 130, Working On or Near Live Parts
8/12/2019 Subcontractor Elec
7/38
EFCOG Electrical Safety Task Group 7
NFPA 70E Training Requirements
Employees shall be trained to understand specifichazards associated with electrical energy
Trained in safety related work practices and proceduralrequirements for specific job or task
Trained to understand relationship between electricalhazards and possible injury
Training shall be classroom or on-the-job type orcombination
Employees working on or near energized conductors shallbe trained in release of victims from contact
8/12/2019 Subcontractor Elec
8/38
EFCOG Electrical Safety Task Group 8
NFPA 70E Qualified Person
A qualified person shall be trained and knowledgeable ofconstruction and operation of equipment or workmethod and trained to recognize and avoid hazard(110.6(D)(1))
Familiar with precautionary techniques, personal protectiveequipment including arc flash, insulating and shieldingmaterials, insulated tools and test equipment
Distinguish exposed energized parts from other parts
Determine nominal voltage of live parts Understand safe approach distances in Table 130.2C Determine personal protective equipment for task
8/12/2019 Subcontractor Elec
9/38
EFCOG Electrical Safety Task Group 9
NFPA 70E Job Briefing
Before starting each job, employee in charge shallconduct a job briefing with employees involved.(110.7G)
Identify hazards Identify procedures to be followed Special precautions Energy source controls Personal protective equipment
8/12/2019 Subcontractor Elec
10/38
EFCOG Electrical Safety Task Group 10
Electrical Safe Work Condition
Live parts to which an employee might be exposed shallbe put into an electrically safe work condition before anemployee works on of near them unless the employeecan demonstrate work on energized components canbe justified (110.8A)
Deenergizing introduces additional or increased hazards(Examples include interruption of life support equipment,deactivation of emergency alarm systems, shutdown of
hazardous location ventilation equipment) Deenergizing is infeasible due to equipment design oroperational limitations. (Examples include start-up ortroubleshooting diagnostics and testing)
8/12/2019 Subcontractor Elec
11/38
8/12/2019 Subcontractor Elec
12/38
EFCOG Electrical Safety Task Group 12
Achieving an Electrically Safe Work Condition
An Electrically Safe Condition shall be achieved by completing allthe followingDetermine all sources of electrical supply (Drawings, diagrams)Open disconnecting device for each source
Visually verify all blades of disconnecting devices are fully openor drawout-type breakers are withdrawnApply lockout/tagout devices in accordance with policyTest each phase conductor using adequately rated voltage
detectorGround phase conductors where possibility exists for inducedor stored energy
8/12/2019 Subcontractor Elec
13/38
EFCOG Electrical Safety Task Group 13
Achieving an Electrically Safe Work Condition
Electrical conductors and circuit parts that have beendisconnected but not under lockout/tagout, tested andgrounded (where appropriate) shall not be considered
to be in an electrically safe work condition Safe work practices shall be used in this case identical toworking on or near exposed live parts
Applies regardless of whether equipment is temporary,
permanent or portable
8/12/2019 Subcontractor Elec
14/38
EFCOG Electrical Safety Task Group 14
Energized Electrical Work
If live parts are not placed in an electrically safe workcondition, work shall be considered energizedelectrical work
A written Energized Electrical Work Permit shall be requiredwhere live parts are not placed in an electrically safe workcondition.
Exemption: work such as testing, troubleshooting, voltagemeasurement shall be permitted to be performed without anenergized electrical work permit provided appropriate safework practices and PPE are provided and used.
8/12/2019 Subcontractor Elec
15/38
EFCOG Electrical Safety Task Group 15
Elements of Energized Electrical Work Permit
Permit shall include the following items Description of circuit and equipment to be worked Justification for performing work in energized condition
Description of safe work practices Results of shock hazard and flash hazard analysis Shock protection boundary Personal protective equipment Means to restrict access to unqualified persons Evidence of job briefing Work approval signatures
8/12/2019 Subcontractor Elec
16/38
EFCOG Electrical Safety Task Group 16
Working on or Near Exposed ElectricalConductors or Circuit Parts
Perform electrical hazard analysis if live parts (50 volts ormore) can not be placed in an electrically safe workcondition
Shock Hazard Analysis (Determine limited, restrictedand prohibited approach boundaries and shock PPE)Flash Hazard Analysis (Determine arc flash boundaryand PPE for personnel within this boundary)Use Energized Electrical Work Permit
8/12/2019 Subcontractor Elec
17/38
EFCOG Electrical Safety Task Group 17
Shock and Arc Boundaries
8/12/2019 Subcontractor Elec
18/38
EFCOG Electrical Safety Task Group 18
Limits of Approach Limited ApproachBoundary
Energizedpanel
(
8/12/2019 Subcontractor Elec
19/38
EFCOG Electrical Safety Task Group 19
m s o pproac es r c e pproacBoundary
Energizedpart
Prohibited Restricted The closest distance toexposed live parts aqualified person canapproach w/out properPPE and tools.
To cross this boundary,the qualified personmust wear PPE andhave proper tools.
12 inches for480 volts
8/12/2019 Subcontractor Elec
20/38
EFCOG Electrical Safety Task Group 20
Limits of Approach - Shock
Energizedpart
Prohibited
Crossed ONLY by a qualifiedperson, which when crossed bybody part or object, requires thesame protection as if directcontact was made with the live
part.1 inch for
480 volts
8/12/2019 Subcontractor Elec
21/38
EFCOG Electrical Safety Task Group 21
Approach Boundaries for Shock Protection
8/12/2019 Subcontractor Elec
22/38
EFCOG Electrical Safety Task Group 22
Limits of Approach Flash ProtectionBoundary
Energizedpart
Prohibited Restricted Limited
The distance from exposedlive parts within which aperson could receive asecond degree burn if anarc flash were to occur.
Arc flash PPE is requiredwithin this boundary.
Note:Distance may beless than or greater thanthe shock protectionboundaries.
Calculated distance
FlashProtectionBoundary
8/12/2019 Subcontractor Elec
23/38
EFCOG Electrical Safety Task Group 23
Flash Hazard Analysis
An arc flash hazard analysis shall be done to protectpersonnel from injury by arc flash exposureThis analysis determines the flash protection boundaryand potential thermal exposure to personnel workingon or near exposure live parts within the boundaryPersonal protective clothing and protective equipmentfor workers inside the flash protection boundary arethen selected to mitigate potential thermal exposureEquipment may be labeled with the results of the arcflash hazard analysis and shock protection analysis
8/12/2019 Subcontractor Elec
24/38
EFCOG Electrical Safety Task Group 24
Typical Equipment Label
8/12/2019 Subcontractor Elec
25/38
8/12/2019 Subcontractor Elec
26/38
EFCOG Electrical Safety Task Group 26
Examples of PPE
Hazard RiskCategory 1
Hazard RiskCategory 2
Hazard RiskCategory 3
Hazard RiskCategory 4Hazard Risk
Category 0
8/12/2019 Subcontractor Elec
27/38
EFCOG Electrical Safety Task Group27
Alternative to Flash Hazard Analysis
The PPE requirements of NFPA 70E, 130.7(C)(9)(a) shallbe permitted in lieu of the detailed flash hazardanalysis
Use Table 130.7(C)(9)(a) to determine hazard/risk categoryfor task Ensure the short circuit capacities and fault clearing time for
task listed in the text and notes are not exceeded
Use Table 130.7(C)(10) to determine the PPE for the task
8/12/2019 Subcontractor Elec
28/38
EFCOG Electrical Safety Task Group28
Table 130.7(C)(9)(A)
8/12/2019 Subcontractor Elec
29/38
EFCOG Electrical Safety Task Group29
Table 130.7(C)(10)
8/12/2019 Subcontractor Elec
30/38
EFCOG Electrical Safety Task Group30
Example Using Alternative Method
Work task involves testing for absence of voltage inside a480 volt MCC cubicle to establish a lockout point.
What is the Hazard/Risk Category?
What notes apply to the task? Are V-rated glove and tools required? What PPE is required for the Qualified Worker?
8/12/2019 Subcontractor Elec
31/38
EFCOG Electrical Safety Task Group31
Example Using Alternative Method
AnswerRefer to 600 V Class Motor Control Centers section in Table130.7(C)(9)(A) and choose task for work on energized parts,including voltage testing. Hazard/Risk Category is 2*
Notes 2 and 3 apply to this task. Confirm with Engineering thatshort circuit current of 65kA and 0.03 fault clearing time notexceeded. If short circuit current < 10 kA, hazard/risk categorycan be reduced by one number
V-rated gloves and tools are required
8/12/2019 Subcontractor Elec
32/38
EFCOG Electrical Safety Task Group32
Example Using Alternative Method
Using Table 130.7(C)(10), identify PPE requirement listedunder Category 2
T-shirt
Long sleeve FR shirt and pants or coveralls Hard hat Safety glasses or safety goggles Flash suit hood and hearing protection (2* footnote to Table
130.7(C)(9)(A) requires hood for this task) Leather gloves over voltage rated gloves Leather work shoes
8/12/2019 Subcontractor Elec
33/38
EFCOG Electrical Safety Task Group33
Personal Protective Equipment Care
Clothing shall be inspected prior to use by user. Clothing or flash suits that are damaged shall not be used. Clothing that become contaminated with grease, oil or flammable liquids
or combustible materials shall not be used.
V-rated gloves shall be inspected prior to use by user. Shall betested and certified every 6 months.
8/12/2019 Subcontractor Elec
34/38
EFCOG Electrical Safety Task Group34
Inspecting Voltage Rated Gloves in Field
Visual Inspection
Inflation
Reverse glove and repeat
Store in appropriate glove bag
8/12/2019 Subcontractor Elec
35/38
EFCOG Electrical Safety Task Group35
Precautions Working on or Near Live Parts
Dont reach blindly into areas that might containexposed live partsProvide illumination in spaces to enable safe work
Conductive articles of jewelry and clothing such aswatchbands, bracelets, necklaces shall not be wornUse only insulated tools rated for voltage whenworking inside the Limited Approach Boundary ofexposed live parts where contact might be made
http://www.aplussafety.net/products/store.cfm?d=3053&c=4194&p=15992&do=detail8/12/2019 Subcontractor Elec
36/38
EFCOG Electrical Safety Task Group36
Typical Voltage Rated Insulated Tools
http://www.aplussafety.net/products/store.cfm?d=3053&c=4194&p=15992&do=detail8/12/2019 Subcontractor Elec
37/38
EFCOG Electrical Safety Task Group37
Alerting and Barricades
How to protect the shock and arc flash approachboundaries from an unqualified person?
Barrier tape Orange cones Signage Plastic chain Use an attendant to warn others approaching the area
8/12/2019 Subcontractor Elec
38/38
EFCOG Electrical Safety Task Group38
NFPA 70E Compliance for Subcontractors
Summary NFPA 70E is more than just Arc Flash requirements Elements provided, but entire standard may be applicable
Chapter 1 provides Safety-Related Work Practices Subcontractor responsible for own personnel safety Communication both ways is imperative