Hot Work Permit: What It Covers, What OSHA Requires, and How to Build Your Program

Most hot work fires don’t start during welding. They start after the welder leaves.

Slag lands inside a wall cavity. A spark catches in insulation. The smoldering starts slow, builds for 30 minutes, and by the time someone notices, it’s in the ceiling. The NFPA reports that hot work is a leading cause of industrial fire losses, and the overwhelming majority are preventable. Not through better welding technique, but through a permit system that forces a deliberate inspection before the torch ever lights.

That’s what a hot work permit actually does. It’s not compliance theater. It’s a structured checklist that slows down the process long enough to catch the combustibles someone forgot to move.

What Counts as Hot Work

OSHA 1910.252 governs welding, cutting, and brazing in general industry. Under that standard, hot work includes any operation that produces flame, sparks, or heat capable of igniting nearby materials. That covers welding, torch cutting, brazing, soldering, grinding (when it produces sparks), and the use of heat guns near flammable surfaces.

Construction hot work falls under a separate standard, OSHA 1926.352, but the core requirements run parallel. If you’re managing a multi-employer site with both construction and general industry workers doing hot work, you need to know which standard applies to which contractor.

The NFPA also defines hot work broadly in NFPA 51B, the fire prevention standard for hot work operations. NFPA 51B is not an OSHA regulation, but many facilities adopt it by policy, and insurers often reference it in coverage requirements. If your facility has a relationship with an industrial insurer, check whether your policy requires NFPA 51B compliance.

The Permit System: Structure and Logic

The hot work permit system has one core function: it requires someone other than the welder to inspect the area before work starts and sign off that conditions are safe.

That separation matters. Welders are focused on the job. They’re thinking about the weld, not the cardboard box ten feet away or the hydraulic fluid residue on the floor. The permit authorizer is the person whose job is to look at the environment before the heat source appears.

A compliant permit must document the specific work location, the date and authorized time window, the type of hot work being performed, the name of the authorizer, and the name of the fire watch. It should also record what fire prevention measures were taken before work started.

The permit isn’t retroactive. You can’t fill it out after the weld is done. The whole point is the pre-work inspection.

Under OSHA 1910.252(a)(1), the area must be inspected before hot work begins to identify and eliminate or control fire hazards. The permit documents that inspection happened.

Area Preparation Before the Torch Lights

This is where most programs fall short. The permit form exists, someone signs it, but the actual area prep gets skipped because the job is running behind.

OSHA 1910.252(a)(2) sets out specific requirements for the work area. Combustible materials within 35 feet of the work must be moved or protected. If they can’t be moved, they must be covered with fire-resistant blankets or shields. Floors must be swept clean of combustibles. If the work is being done near walls, partitions, or floors that contain combustible materials or voids, those surfaces need to be wetted or shielded.

This 35-foot rule surprises people. That’s a large radius. In a cluttered maintenance shop or a warehouse, clearing that zone before every hot work job is real work. But sparks from grinding travel farther than most people expect, and slag from cutting can bounce across a concrete floor much further than the immediate work area.

Equipment preparation matters too. Compressed gas cylinders must be secured upright and away from the work area. Torch hoses must be inspected for cracks or leaks before use. Oxygen and fuel cylinders need to be stored separately, per OSHA 1910.253. If you’re managing the full equipment program, the PPE guide covers the protective equipment requirements specific to welders.

Fire Watch Requirements

OSHA 1910.252(a)(2)(iii)(A) requires a fire watch any time welding or cutting takes place near combustibles that could be ignited by sparks, when combustibles are within 35 feet, when combustibles outside the 35-foot radius could still be reached by sparks traveling through openings, or when wall or floor openings expose adjacent areas to spark ignition.

In practice, most industrial hot work requires a fire watch. The situations where you clearly don’t need one, work in a bare concrete room with no combustibles anywhere near the space, are uncommon.

The fire watch has specific duties under the standard. They must be equipped with a suitable extinguisher. They must watch for fires in all exposed areas for the entire duration of hot work. And they must remain on watch for a minimum of 30 minutes after the hot work ends.

That 30-minute post-work watch is where programs fail most often. The welder finishes, packs up, leaves. The fire watch figures the job is done and follows. But the fire that starts 20 minutes later in the wall cavity was already ignited before the torch went out.

Some facilities extend the post-work watch to 60 minutes by policy. Many industrial insurers require it. If you’re operating in a facility with wood-frame construction or walls with combustible insulation, 60 minutes is the right call.

The fire watch cannot be the welder. This is explicit in the standard. It also can’t be a person who has other tasks to perform during the hot work. A fire watch with competing duties is not a fire watch.

What a Compliant Hot Work Program Looks Like

The permit is the visible part of the program. The program itself is broader.

A compliant program starts with a written policy that defines what constitutes hot work at your facility, who is authorized to approve permits, and what the permit issuance process looks like. It names the specific person or role responsible for the permit program, not just “management.”

Training is required under 1910.252(a)(1)(iii). Workers performing hot work must be trained on fire prevention and on the permit system. Authorizers must know what they’re inspecting for. Fire watches must know their duties and know how to use the extinguisher assigned to them.

Permits must be retained. OSHA doesn’t specify a retention period for hot work permits in 1910.252, but keeping completed permits for at least one year is standard practice and supports post-incident investigation. If a fire does occur, the permit is evidence. Make sure it’s legible and complete before archiving it.

The program should also have a procedure for what happens when hot work can’t safely proceed, when the authorizer inspects and finds conditions that aren’t acceptable. Workers need to know they can stop and that stopping is supported. That’s a cultural piece, and it connects to the work you’d do in a job hazard analysis before putting hot work on the schedule.

If your facility’s response to a hot work emergency isn’t documented, your emergency action plan should cover fire response explicitly. Hot work areas are higher-risk zones and should be called out in evacuation planning.

Common Failures

The permit exists but the area prep doesn’t happen. Someone signs the form without inspecting the zone.

The fire watch leaves early. The 30-minute rule gets treated as optional.

The permit covers “building B” but the work happens in multiple locations throughout building B over the course of a shift. Permits aren’t location-specific enough.

Hot work gets performed by a contractor without any permit issuance because someone assumed the contractor had their own system. Under OSHA’s multi-employer citation policy, the host employer can be cited for contractor hot work conducted on their premises without a permit.

Grinding gets exempted from the permit program because “it’s not really hot work.” Grinding sparks ignite fires. It qualifies.

If you manage electrical work alongside hot work, the NFPA 70E certification covers the electrical side of permit-required work and is worth understanding for maintenance departments that deal with both.

Building Your Program From Scratch

Start with the permit form. Keep it one page. Location, date, time window, type of work, authorizer signature, fire watch name, and a checklist of the pre-work conditions that were confirmed. Items should include: combustibles cleared to 35 feet, floors swept, wall/floor openings covered, fire watch equipped with extinguisher, gas cylinders secured.

Then build the training. Authorizers need to physically walk the checklist before signing. Fire watches need hands-on extinguisher training, not just a video.

Then establish the retention system. Even a binder organized by month works. What matters is that the permits exist and can be retrieved.

OSHA citations for hot work program deficiencies often come after fires, not during random inspections. By then, the permit record is the difference between a defensible response and a serious citation.