For the welder or cutter doing hot work: make the area fire safe before you strike an arc, know when a fire watch is required and what it does, handle containers and walls safely, protect your eyes and lungs, and leave the job safe when you stop.
Based on OSHA 29 CFR 1910.252 (general industry) and 29 CFR 1926.351(e), 1926.352 and 1926.353 (construction) · about 9 min read
Need proof of training? The full course (25 min) adds practice questions, a job scenario, the final quiz and a certificate your employer can verify.
Before hot work, work through these three questions in order.
1. Can the work move?On construction sites, when practical, move the object to a designated safe location. If it cannot readily be moved, take all movable fire hazards nearby to a safe place, or otherwise protect them. (General industry: if the object cannot readily be moved, take movable fire hazards nearby to a safe place.)
2. Can the hazards be guarded?If the object cannot be moved and not all fire hazards can be removed, use guards to confine the heat, sparks and slag and protect what cannot move.
3. Neither? Stop.In general industry, if you cannot do step 1 or step 2, welding and cutting shall not be performed.
Get authorization first
In general industry, before cutting or welding is permitted, the area must be inspected by the person responsible for authorizing hot work. That person sets the precautions, preferably in a written permit. Follow the precautions it sets.
Where practicable, relocate all combustibles at least 35 feet (10.7 m) from the work. If that is impracticable, protect them with flameproofed covers or shield them with metal guards or curtains.
If paper clippings, wood shavings or textile fibers are on the floor, sweep it clean for a radius of 35 feet. Keep combustible floors wet, covered with damp sand, or protected by fire-resistant shields. Where floors have been wet down, people operating arc welding or cutting equipment must be protected from possible shock.
Floor openings or cracks that cannot be closed: make sure sparks cannot drop onto readily combustible material below. Take the same precautions with cracks or holes in walls, open doorways and open or broken windows.
Ducts and conveyors that could carry sparks to distant combustibles must be protected or shut down.
Never weld or cut here (general industry)
In areas not authorized by management
In sprinklered buildings while the sprinklers are impaired
In explosive atmospheres, including inside uncleaned tanks or equipment that held flammables, or areas with built-up combustible dust
Near storage of large quantities of exposed, readily ignitible materials such as bulk sulfur, baled paper or cotton
On construction sites, no welding, cutting or heating where flammable paints, other flammable compounds or heavy dust concentrations create a hazard.
In general industry, fire watchers are required whenever you weld or cut where other than a minor fire might develop, or when any of these is true:
Appreciable combustible material, in the building or its contents, is closer than 35 feet to the point of operation.
Appreciable combustibles are more than 35 feet away but are easily ignited by sparks.
Wall or floor openings within a 35-foot radius expose combustible material in nearby areas, including concealed spaces in walls or floors.
Combustibles are against the opposite side of metal partitions, walls, ceilings or roofs and are likely to be ignited by conduction or radiation.
On construction sites, when normal fire prevention precautions are not sufficient, additional people must be assigned to guard against fire during the work and for a sufficient time afterward to ensure no possibility of fire exists.
Your part as the welder: if any of these conditions applies, do not start until the fire watch is in place.
Equipped and trainedHas fire extinguishing equipment readily available and is trained to use it.
Knows the alarmKnows how to sound the alarm if a fire starts.
Watches all exposed areasTries to put out a fire only when it is obviously within the capacity of the equipment on hand. Otherwise sounds the alarm.
Stays after you stopIn general industry, the fire watch is kept for at least a half hour after welding or cutting is finished, to catch smoldering fires.
On construction sites, fire watch personnel must be instructed on the specific fire hazards expected and how to use the firefighting equipment provided.
Extinguishing equipment ready
On construction sites, suitable fire extinguishing equipment must be immediately available in the work area and ready for instant use. In general industry, suitable fire extinguishing equipment must be maintained in a state of readiness for instant use. It may be pails of water, buckets of sand, hose or portable extinguishers, depending on the combustibles exposed.
An "empty" drum that has not been cleaned can hold an explosive atmosphere. Before you put heat on any used container:
General industry: no hot work on used drums, barrels, tanks or other containers until they are cleaned so thoroughly that there is absolutely no flammable material, and nothing like greases, tars or acids that could give off flammable or toxic vapors when heated. Disconnect or blank any pipe lines or connections.
Construction: drums, containers or hollow structures that held toxic or flammable substances must either be filled with water, or thoroughly cleaned, ventilated and tested, before welding, cutting or heating.
Vent it: hollow spaces, cavities and containers must be vented so air or gases can escape before preheating, cutting or welding. On construction sites, provide a vent or opening to release built-up pressure before heat is applied.
Heat travels through metal. A fire can start on a side of the wall you cannot see. The first three rules below are general industry (1910.252); the last one is the construction rule.
Metal wall, partition, ceiling or roof: prevent ignition of combustibles on the other side, preferably by relocating them. If they are not relocated, a fire watch on the opposite side must be provided.
Never weld on a metal partition, wall, ceiling or roof with a combustible covering, or on combustible sandwich-type panels.
Near combustible construction: fire-resistant shields or guards must be provided to prevent ignition.
Construction sites: when you weld, cut or heat walls, floors or ceilings, take the same precautions on the opposite side as on your side.
Arc welding or arc cuttingUse a helmet or hand shield for all arc welding or arc cutting (submerged arc welding excluded). Helpers and attendants must also get proper eye protection.
Gas welding or oxygen cuttingUse goggles or other suitable eye protection. Spectacles without side shields, with suitable filter lenses, are permitted for gas welding on light work, for torch brazing or for inspection.
OSHA's shade-number table for filter lenses is a guide; its recommendations may be varied to suit the individual's needs. Filter lenses must still meet the test for transmission of radiant energy in the consensus standards listed in 29 CFR 1910.133(b)(1).
Protect the people near you
In general industry, workers and others next to the welding area must be protected from the rays by noncombustible or flameproof screens or shields, or must wear appropriate goggles.
Construction sites
Employees doing any type of welding, cutting or heating must be protected by suitable eye protective equipment under Subpart E. Whenever practicable, all arc welding and cutting must be shielded by noncombustible or flameproof screens that protect employees and others working nearby from the direct rays of the arc.
Keep paths clear
Place welding cable and other equipment clear of passageways, ladders and stairways.
In general industry, local exhaust or general ventilation must be provided and arranged to keep toxic fumes, gases or dusts below the maximum allowable concentration.
On construction sites, local exhaust uses freely movable hoods meant to be placed by the welder as close as practicable to the work. That means you position the hood.
On construction sites, never use oxygen for ventilation, comfort cooling, blowing dust off clothing, or cleaning the work area. In general industry, oxygen shall never be used for ventilation.
In general industry, fluxes, coatings, coverings and filler metals can contain potentially hazardous materials. Your employer must give you access to their labels and safety data sheets and train you under the Hazard Communication Standard. Read them before you weld.
Stopping arc welding for a substantial time, such as lunch or overnight: remove all electrodes from the holders, place the holders so accidental contact cannot occur, and disconnect the machine from power.
Stopping gas welding or cutting for a substantial time: close the torch valves and positively shut off the fuel-gas and oxygen supply outside the confined area. Where practicable, also remove the torch and hose from the confined space.
Construction sites
Whenever the torch is not to be used, or is left unattended for a substantial period such as lunch, positively shut off the gas supply to the torch outside the enclosed space. Overnight and at shift change, remove the torch and hose from the confined space. Open-ended fuel gas and oxygen hoses must be removed from enclosed spaces immediately once disconnected from the torch.
When you finish
In general industry, after welding in a confined space, mark the hot metal or warn other workers some other way. This rule sits in the confined-space paragraph of 1910.252(b)(4); marking hot metal is a good practice on every job. Hot steel looks just like cold steel.
Fact-checked against the regulation text on October 09, 2026. This certificate records completion of awareness training based on OSHA 29 CFR 1910.252 (general industry) and 29 CFR 1926.351(e), 1926.352 and 1926.353 (construction). It is not an OSHA card or license, and it does not by itself meet the training and instruction requirements of 29 CFR 1910.252(a)(2)(iii)(B), 1910.252(a)(2)(xiii)(C) and 1910.252(c)(1)(iv), or 29 CFR 1926.350(d), 1926.351(d) and 1926.352(e). Your employer must still make sure cutters or welders and their supervisors are suitably trained in the safe operation of their equipment and the safe use of the process, that fire watchers are trained in the use of the fire extinguishing equipment, and that you are trained under the Hazard Communication Standard on the hazardous materials in fluxes, coatings, coverings and filler metals. On construction sites, your employer must thoroughly instruct employees in the safe use of fuel gas and in the safe means of arc welding and cutting, and instruct fire watch personnel as to the specific anticipated fire hazards and how the firefighting equipment provided is to be used. In general industry, hot work also needs authorization from the individual responsible for authorizing cutting and welding operations.
This guide explains the rule in plain words. Always read the regulation itself and your employer's site-specific procedures.