Hazards from Electric Arc Welding

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Chapter : Welding Safety

Electric arc welding is a process that fuses metals using an intense electric arc generated between two terminals of an electrical circuit, which creates enough heat to melt the materials. Electric arc welding can expose workers to a number of hazards, including electric shock, fires, explosions, and radiation. 

Hazards from Electric Arc Welding

• The biggest hazard in arc welding is not from heat, sparks, fumes or intense infrared radiation but from electrical current (electrocution).
• On most manual arc welding operations, the electric current ranges from 10 amps to 600 amps. Remember that it only takes 70 to 100 milliamps to kill most people and 70 milliamps is only a fraction of one single amp.
• Your best protection is to keep from becoming grounded.
• Make sure you are always insulated from the work itself because it is probably grounded. For example, if you are welding one pipe to another pipe that is already in place, the new pipe also becomes grounded. If you are not insulated from it you too will become grounded.
• Inspect the stinger leads for damage. There can be no damage in the first 10 feet of active stinger lead. Minimal lead damage elsewhere can be repaired by a qualified person with vulcanizing or heat shrinking kits.
• Always keep yourself insulated from the electrode and electrode holder, especially if you are wet from sweat or some other source. Use well insulated electrode holders and welding cables.
• Keep your clothes and hands as dry as possible. Use insulation between your body and the ground such as a welding mat, where possible.
• Cover or otherwise arrange the cables in a way that will prevent falling sparks from burning through the insulation.
• Avoid changing electrodes with bare hands or wet gloves. 

Required Personal Protective Equipment:  Safety Eyewear, Safety Footwear, Leather Gloves, Hearing Protection, Apron, Welding Bib, Full-face Welding Helmet

Risk / Job Safety  Analysis:

Step	Description	Hazard	Controls
1	Set up workpiece on fixture	a) Strain/sprain from heavy and/or awkward workpiece-- b) Foot injury from dropping workpiece-- c) Trip/fall in area around Arc Welding workstation-- d) Damage to workpiece from incorrect set-up-- e) Hand/finger laceration from edge of workpiece-- f) Hand/finger contusion from tool slippage while tightening fixture	a) Use mechanical hoist or get assistance from co-worker to set-up/ adjust workpiece-- b) Wear recommended footwear.  Ensure workpiece is securely clamped to fixture-- c) Clean/clear work area/surfaces of unused tools/materials.  Remove dust/debris.-- d) Workpiece should be clean and secure to fixture-- e) Wear recommended gloves when handling workpieces with sharp edges-- f) Use correct tool and wear recommended gloves
2	Install electrode rod into torch	Electric shock/burn from electrode rod	Ensure Arc Welding machine power to arc is electrically de-energized when changing electrical rod
3	Energize and set Arc Welding Machine amperage/ current	a) Electrical shock/burn from contact with electrode rod holder b) Damage to workpiece from incorrect amperage/current	a) Ensure welding machine is properly grounded.   Welder should be insulated from live electrical parts and dry.  Inspect and replace cables, plugs and leads that show any signs of defects.  Wear recommended gloves and clothing. b) Refer to Op Sheet and/or Shop Order for correct amperage/current
4	Turn on gas and set flow	a) Damage to workpiece from incorrect gas flow rate b) Bodily injury from explosion of compressed gas cylinder--	a) Consult Op Sheet and/or Shop Order for correct flow rate b) Practice caution around compressed gas cylinders.  Protect gas cylinders from excessive heat, mechanical shocks and arcs.  Ensure cylinder is insulated and fastened so it will not fall.  Do not use a compressed gas cylinder that appears to be damaged and/or defective.
5	Weld workpiece	a) Eye injury from welding flash and/or spatter-- b) Burns from welding spatter, UV/infrared radiation and/or electrical contact-- c) Inhalation of welding fumes or asphyxiation from displaced oxygen-- d) Bodily injury from condition or type of workpiece being welded-- e) Electrical shock hazard-- f) Hearing loss from chronic exposure to noisy machinery-- g) Fire due to combustible material in welding area-- h) Hand/finger contact burn from hot electrode rod	a) Wear welding helmet with proper grade of filter plate.  Ensure flash curtains/barriers are used to protect bystanders/observers-- b) Wear recommended protective clothing.  Ensure any exposed skin is covered during the welding process.  Do not wear metal jewelry and clothing with cuffs and/or pockets.  Stay a safe distance away from arc-- c) Use local exhaust ventilation and a fan to maintain good air circulation-- d) Do not weld workpiece unless it is properly cleaned-- e) Ensure welding machine is properly grounded.  Welder should be insulated from live electrical parts and dry.  Do not weld when wet.  Inspect and replace cables, plugs and leads that show any signs of defect.-- f) Wear hearing protection-- g) Remove any combustible material from the immediate welding site.  Keep a fire extinguisher readily available.-- h) When electrode rod gets too short, stop welding and restart with a new electrode rod.  Wear recommended gloves.
6	Complete welding	Electrical shock/burn or electrical contact with conducting objects, flammable liquids and/or compressed gas cylinders due to energized electrode rod holder	Ensure Arc Welding machine power to arc is electrically de-energized.   When not in use electrode rod should be removed from holder and holder should be placed so it cannot make electrical contact with conducting objects, flammable liquids and/or compressed gas cylinders.
7	Remove workpiece from fixture and transport to inspection	a) Strain/sprain from heavy and/or awkward workpiece-- b) Foot injury from dropping workpiece-- c) Trip/fall in area around Arc Welding workstation-- d) Hand/finger laceration from edge of workpiece-- e) Hand/finger contusion from tool slippage	a) Use mechanical hoist or get assistance from co-workers to transport workpiece-- b) Wear recommended footwear.  Ensure workpiece is securely clamped to fixture-- c) Clean/clear work area/surfaces of unused tools/materials.  Remove dust/debris regularly-- d) Wear recommended gloves when handling workpieces with sharp edges-- e) Use correct tool and wear recommended gloves

Ground the welding unit according to the National Fire Protection Association’s National Electrical Code (NFPA 70).