155 Welding Safety: Basic

Fire Prevention and Protection

Eliminate fire and explosion hazards by removing or reducing combustible or explosive materials or vapors by preventing them from accumulating. The methods for making a space safe for welding and the tests used to ensure a space is free of fire and explosion hazards should be the welding supervisor's responsibility.

Special Precautions for Fire Prevention

Combustible Material

Wherever there are floor openings or cracks in the flooring that you cannot close, you should take precautions so no readily combustible materials on the floor below is exposed to sparks that might drop through the floor. Use the same precautions for cracks or holes in walls, open doorways and open or broken windows.

Combustible Covers

Never weld on a metal partition, wall, ceiling or roof having a combustible covering nor on walls or partitions of combustible sandwich-type panel construction.

Floors

Where combustible materials such as paper clippings, wood shavings, or textile fibers are on the floor, sweep the floor clean within a radius of 35 feet (10.7 m). In addition:

• If floors are combustible, keep them wet, covered with damp sand, or protected by fire-resistant shields.
• Protect workers operating arc welding or cutting equipment from shock where floors have been wet down.

Ducts

Protect or shut down ducts and conveyor systems that might carry sparks to distant combustibles.

Combustible Walls

Where cutting or welding is done near walls, partitions, ceiling or roof of combustible construction, provide fire-resistant shields or guards to prevent ignition.

Non-combustible Walls

If you need to do welding on a metal wall, partition, ceiling or roof, prevent ignition of combustibles on the other side, preferably by relocating combustibles. Where you are not able to relocate the combustibles, be sure to provide a fire watch on the opposite side from the work.

Pipes

Do not cut or weld on pipes or other metal in contact with combustible walls, partitions, ceilings or roofs if the work is close enough to cause ignition by conduction.

Fire Extinguishers

Position suitable fire extinguishing equipment and maintain it in a state of readiness for instant use. Depending on the nature and quantity of the combustible material, fire-extinguishing equipment may consist of:

• pails of water,
• buckets of sand,
• hoses, or
• portable extinguishers.

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