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Welding Safety
Cummins Southern Plains, Ltd.
Welding SafetyHealth HazardsElectrical HazardsFire & Explosion HazardsTrips and FallsCompressed Gas Hazards Identifying HazardsReducing HazardsBasic Safety Rules
Health Hazards Gases and Fumes… Welding “Smoke” is a mixture of very fine particles
called fumes and gases Welding “Smoke” contains fumes and gases including…
Chromium, nickel, arsenic, asbestos, manganese, silica, beryllium, cadmium, nitrogen oxides, phosgene, acrolein, flourine compounds, carbon monoxide, cobalt, copper, lead, ozone, selenium, and zinc
Health Hazards…Gases & Fumes Generally, gases and fumes come from…
Base material & filler materialCoatings & paintsShielding gases & chemical reactionsProcess & consumables usedContaminants in the air
Health Hazards It is difficult to list all the health effects of welding
exposures because the fumes may contain so many different substances that are known to be harmful
The individual components of welding “smoke” can affect just about any part of the body, including the lungs, heart, kidneys, & central nervous system
Health Hazards Exposure to welding “smoke” may have… Short-term effects…
Effects happen at or very soon after exposure Long-term effects
Effects may happen after repeated overexposures or an extended time after the exposure
Short-term exposures Exposure to zinc, magnesium, copper and
copper oxide can cause metal fume fever Symptoms of metal fume fever may occur 4 to
12 hours after exposure Symptoms include…
Chills, thirst, fever, muscle ache, chest soreness, coughing, wheezing, fatigue, nausea, and metallic taste in mouth
Short-term exposures Welding “smoke” can irritate
the eyes, nose, chest and respiratory tract
Welding “smoke” can cause coughing, wheezing, shortness of breath, bronchitis, pulmonary edema, and pneumonitis
Welding “smoke” can cause nausea, loss of appetite, vomiting, cramps, and slow digestion
Long-term exposures Studies of welders, flame cutters, and burners
have shown that welders have an increased risk of lung cancer…
and…possibly cancer of the larnyx and urinary tract
Remember… welding “smoke” can include cancer causing agents such as…cadmium, nickel, beryllium, chromium, and arsenic
Other Health Risks… Heat exposure…
Heat stress, heat stroke Burns, eye injuries from hot slag, metal chips, sparks,
and hot electrodes Shirts
keep collar and sleeves buttoned to keep out sparks and remove pockets or tape them shut
Pantsno cuffs and come over shoe tops
Other Health Risks… Visible light, and ultraviolet and infrared radiation Intense light can cause damage to retina Infrared radiation may damage the cornea and
result in cataracts Invisible UV light can cause “arc eye” or
“welders’ flash”May include sandy or gritty eye, blurred vision, intense pain, tearing, burning and headache
DANGERDO NOTWATCH
ARC
Other Health Risks… Permanent eye damage Skin burns Skin cancer Noise
Can result in stress, increased blood pressure, may contribute to heart disease, tiredness, nervousness, and irratability
Electrical Hazards Even though welding generally uses low voltage,
there is still a danger of electric shock Wet work areas, Cramped work spaces Falls, fractures and other accidents can result
from electrical exposure Even small shock can cause brain damage Death can occur from large shocks
Electrical Hazards Always use dry gloves Always wear rubber soled shoes Always use insulating layers Protect yourself from surfaces that conduct electricity When working on electrically powered machinery, make sure
the frame is grounded Keep insulation on all welding equipment and components
dry and in good condition Don’t change electrodes with bare hands, wet gloves or
while standing on wet or ungrounded surfaces
Fire and Explosion Hazards
Intense heat and sparks can cause fires or explosions if in the vicinity of combustible or flammable materials
Welding and cutting should only be performed in areas free of combustible materials such as trash, wood, paper, textiles, plastics, chemicals, and flammable dusts, liquids and gases
Cutting torch temperatures can exceed 5000 degrees F
Suitable fire extinguishers shall be maintained in a state of readiness
Fire Watchers are required whenever welding and cutting is performed in locations where other than a minor fire might develop
Fire Prevention and Protection
Fire Watchers are also required when:Appreciable combustible materials, in building construction or contents, are closer than 35 feet to the point of operationAppreciable combustible materials more than 35 feet away but are easily ignited by sparksA fire watch shall be maintained for at least one half hour after the completion of welding or cutting operations
Fire Prevention and Protection
Fire and Explosion Hazards
Never weld or cut on containers that have held a flammable or combustible material unless the container is thoroughly cleaned or filled with an inert gas
A fire inspection should be performed prior to leaving a work area and for at least 30 minutes after the operation is completed
Fire extinguishers should be nearby, of proper size, type and number for the hazards involved
Case StudyArc welder dies in explosion while using an old barrel as a
worktable A 38-year-old male arc welder died as a result of an
explosion at a construction company.The victim was arc welding some brackets on the back of the truck. He was apparently welding with a wire welder and used a metal 55-gal barrel as a worktable while welding. Apparently the heat or sparks from the welding ignited residual vapors and/or material in the barrel, causing it to explode. The explosion knocked the victim down, and started a fire in the immediate area.
Case StudyRecommendations Ensure welders are suitably trained in
safe operation of equipment and process.
Ensure that welding should not be performed on or near used drums, until they have been thoroughly cleaned.
Develop, implement, and enforce a written safety program, including HOT WORK.
Designate a competent person to conduct frequent and regular site safety inspections.
Trips and Falls To prevent trips and falls…
Keep work areas clear of equipment, machines, cables, and hosesAlways properly maintain and use handrailsAlways use and maintain safety lines, harnesses and lanyardsAlways make sure that scaffolds are properly assembled and used
Compressed Gas Hazards Gas welding and cutting use a
fuel gas and oxygen which are stored in high pressure cylinders
Most fuel gases are explosive Pure oxygen will increase the
flammability of any combustible/flammable material
Identifying Hazards Identify hazards and potential hazards prior to
beginning hot work Read the MSDS sheet to identify the hazardous
material used in welding and cutting products, and the fumes that may be generated
Make sure that you know what you are welding before beginning
Reducing Hazards After a specific hazard(s) has been identified…
You can implement appropriate control method(s)You can use appropriate PPE
PPE
CONTROL
Engineering Controls and Work Practices
UV shields between the worker and other operations can protect against exposures
Use work area barriers to protect others working in the same general area
Barriers can also reduce noise
Filter Lens Shade Numbers Soldering = #2 Torch Brazing = #3 or #4 Light cutting up to 1 inch = #3 or #4 Medium cutting 1 inch to 6 inches = #4 or #5 Heavy cutting over 6 inches = #4 or #6 Light gas welding up to 1/8” = #4 or #5 Medium gas welding 1/8” to ½ “ = #5 or #6 Heavy Gas Welding over ½ “ = #6 or #8
Protective Clothing Fire resistant gauntlet gloves Headcap High top hard toed shoes Leather apron Faceshield Flame retardant clothing Safety Glasses Safety helmet
Hearing Protectors Ear plugs and/or muffs should be worn during
noisy operations such as air arcing or grinding Most welding operations are noisy
Respirators Must be specific to the hazard Must be fitted, cleaned, stored and maintained in
accordance to regulation and manufacturers specs
NIOSH recommends respirators whenever a carcinogen is present
Basic Safety Rules 1. Before you start make sure personal safety is followed. 2. Make sure you have had instruction 3. Release adjusting screw on regulators before opening valves 4. Stand on the opposite side of the regulator when opening a
valve 5. Open cylinder valve slowly, oxygen first all the way open
acetylene just a quarter of a turn 6. Do not use or compress acetylene at pressure higher than 15
psi.
Basic Safety Rules 7. Set working pressures as desired. 8. Light acetylene first, shut it off first 9. Never use oil on regulators or any equipment 10. Do not use oxygen as a substitute for compressed air 11. Keep heat, flames and sparks away from
combustibles. 12. Keep hoses out of sparks or spatter to prevent leaks
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