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Hot work hazards and how to prevent them

Hot work operations are one of the leading causes of fire in Canada and one of the top three losses for mid-size industrial or commercial properties—accounting for a significant portion of property losses each year. But effective safety procedures and a hot work permit system can significantly reduce the fire hazards caused by cutting, welding and other hot work.

Hot work is any type of work that produces an igniting force, such as a spark or open flame, including welding, cutting, grinding, brazing and propane soldering. If hot work is being performed in the presence of combustible dust or flammable liquids, gases or materials, there’s a high risk of fire or explosion.


A small spark could lead to catastrophic loss

Many commercial and light manufacturing properties don’t have a designated area set aside for regularly occurring hot work.

“Lack of a proper, designated hot work area is where some operations go amiss. Conducting hot work within a building may present an unnecessary fire hazard, particularly if that hot work could have alternatively been conducted in a safe, designated area,” says Tyler Bjornson, Director of Loss Control at Wawanesa Insurance. “This could occur in any occupancy such as in a shop or on a farm, for example. Hot work conducted in a production or storage area introduces so many variables, and a proper designated area is preferred whenever possible.”

But a small spark could have big ramifications: destruction of equipment, destruction of property, business interruption and even loss of jobs. It could also put people’s lives at risk. And while rebuilding after a loss, the business may lose customers to their competitors.

“The consequences are huge,” says Bjornson. “All you need is just one little welding spark under the wrong conditions and it’s amazing the destruction that can occur.”

Mitigating the risks of hot work

Perhaps a contractor is cutting metal and a spark jumps into a dusty area near a combustible wall. That spark can smoulder and spark a fire in the middle of the night when no one is around to stop it.

“To mitigate those risks, housekeeping should be amplified in any area where hot work is taking place,” says Andrew Chan, Senior Loss Control Specialist with Wawanesa.

Preferably, the work should take place in an area with non-combustible walls and floors. The area should be clean, well ventilated and free of any combustible materials. Flame-proof covers, metal guards or approved welding curtains can be used if combustibles can’t be removed.

“Ensure that no combustibles are within 35 feet of the hot work area and have portable fire extinguishers nearby,” says Chan.

Performing a fire watch

While plenty can be done to prepare the work site for hot work, it’s also critical to perform a fire watch after the work is performed.

“A fire watch means hanging around to make sure a fire is not going to smoulder or ignite after the hot work has been done, and that seems to be where things go off the hook a lot of times,” Bjornson elaborates. In some cases, responsibility for the fire watch has not been determined prior to the work being conducted. Has the welding contractor priced this into the job? Or is the business providing a trained staff member for the watch period? It’s a critical step that can unfortunately be missed.

That’s why it’s preferable to have the work completed early in the day, rather than at the end of the day when everyone wants to go home.

The recommended time for a fire watch is anywhere from one to four hours, depending on the work performed, and a person trained in the use of fire suppression equipment should perform the fire watch.


Hot work permits

The hazards of hot work can be significantly reduced through the use of a hot work permit system, regardless of whether the work is being done by in-house staff or by third-party contractors.

A hot work permit is a two-part tag system that involves a welder completing a safety checklist prior to proceeding with hot work outside of designated hot work areas. One section of the two-part tag is affixed near the work area until the fire watch is completed, while the other section is generally maintained on file and audited by management.

“The tag is physically affixed near the hot work area, and the system ensures the welder follows safety protocols and signs off on a checklist prior to conducting the hot work and upon completing the fire watch,” says Chan, who notes that you can purchase hot work permit tags from most safety supply retailers.

Hot work fire safety program

Permits should be part of a hot work fire safety policy, which is part of the company’s overall safety program. This policy should refer to all hot work activities performed on-site, either by staff or third-party contractors.

A hot work policy doesn’t have to be overly complicated—it can be a page or two outlining the safety procedures surrounding hot work. 

This basic written policy should include:

  • Company policy regarding all hot work activities performed on-site by maintenance staff or third-party contractors (including the preference to have the work completed off-site or early in the day if within the building).

  • Fire safety procedures (cleanup/wet down/spark watch) to be performed prior to, during and after hot work has been conducted within the building.

  • Mandatory use of an in-house or contractor-provided hot work permit system, except for designated hot work areas.

  • Steps to be taken to ensure any designated hot work areas are kept free of combustible material including open-topped garbage containers.

  • Welding shields are used to achieve separation if necessary.

  • Steps to be taken whenever an independent hot work contractor is requested to perform work on site.

At a minimum, the “Use of Hot Work Contractors” section of your policy should include:

  • Obtaining a current certificate of liability insurance from the contractor.

  • Contractor notification and an agreement to utilize the mandatory permit system.

  • Agreement on who will provide spark/fire watch duties.

The hot work permit program should be in accordance with NFPA 51B, “Safeguards for Fire Prevention During Welding, Cutting and Other Hot Work,” which includes written procedures for issuing a permit.

“Hot work is something that could completely destroy your business while putting lives at risk,” concludes Bjornson. “Investing a little time and establishing a safety program is the right thing to do.”

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