Controlling hot work risks 

Jyrki Eskola, Insurance Investigator in the Investigation unit at If in Finland, has gathered observations across industries on common causes of fire incidents. He notes that accidents often occur near the end of a task, before lunch or late in the workday, when concentration typically starts to slip. 

Actual fire investigations show how small oversights can turn a routine welding job into a serious fire. 

• Granting a hot work permit as a routine without assessing the risks at the actual location
• The location-specific risk assessment is not communicated to the hot worker
• Penetrations, gaps and openings are not properly covered, despite this being specified in the permit and required as a basic precaution
• Surfaces exposed to upward-travelling sparks are not protected or wetted down
• Structures are not opened before work begins, and hidden combustible materials are not identified in spaces where oxygen and draught can create a flue effect
• Sawdust and sawing waste are not thoroughly removed; sweeping the area alone is insufficient
• Safer alternative methods are not considered
• The effect of weather, especially wind, is not sufficiently addressed or reviewed.
• There is insufficient understanding of fire behaviour, the effects of ventilation and the fire properties of different materials
• Extinguishing equipment is not placed close enough to the work area for rapid access in an emergency
• Urgency takes precedence over sound judgement and due consideration

Jonatan Loman, Fire Investigator at If Insurance in Sweden, notes: “Details matter. In one case, the preparations were correct, but the extinguisher and hose were too far from the work area. When a fire started, the workers lost the chance to stop it before it spread.” 

Jyrki Eskola notes: “Alternative methods should be considered during the kick-off meeting. The permit issuer and the hot worker must then assess the risks together before work begins.” 

Thorough planning before work begins remains the best approach to hot work safety, as every task presents different challenges—from the materials used to the careful assessment of the work area and its surroundings. 
 
“A hot work permit must be more than a signed form,” he adds. “It should confirm that the workers can respond to an early-stage fire and that the work area, equipment and possible routes for sparks or heat have been properly checked.” 

Drawing on 20 years of experience as a fire investigator, Eskola says: “Many roof fires could be prevented by avoiding open flames near walls. Contractors should always consider safer, non-flame options, such as adhesive bonding, as alternative ways to complete the job.” 

The fictional case highlights familiar hot work failings: the repair was performed outside a permanent hot work area, combustible materials were not fully removed or shielded, hidden spaces were not adequately checked, and supervision was weak. Those gaps allowed sparks and heat to move beyond the immediate task and develop into a fire out of sight. 

Beyond the inexperienced contractor, the example draws attention to the person who authorised the hot work permit. A permit should only be issued when the worker understands the risks, is properly trained, and the site has been prepared, protected and monitored. When these conditions are not met, a routine maintenance task can become a major loss event. 

Jyrki Eskola notes, “When approving and issuing a hot work permit, the permit issuer must be properly trained to understand the risks associated with the planned task. They are responsible for ensuring that the person carrying out the work is fully aware of the risks, understands the alternative methods available, works only when a fire guard is present, and has the knowledge and skills needed to manage the risks and extinguish an incipient fire.”

Andreas Kräling, Head of Property Risk Management in Sweden, stresses: “Staff should be properly trained, being able to respond promptly when a fire incident occurs. Also, before hot work begins the people and equipment that have been specified in the hot work plan to be present must be in place. If they are not, the agreed controls have failed, and work should not be done.” 

“When a small fire starts, the outcome often depends on immediate human response. Sprinklers also play a vital role; however, they are not always available above a hot work area. A common mistake is, for example, when both the welder and the fire watch leave together for a lunch break, leaving no one to monitor the worksite while they are away. Again, this is a failure in supervision and adhering to guidelines that most companies have in place, but do not enforce.” 

In practice, at least one person should remain on site to watch for smouldering materials or hot tools that could come into contact with combustibles.  

Andreas concludes, “Without continuous monitoring, a hidden fire can develop, not only during a lunch or coffee break, but even an hour after the work has been completed. By the time smoke appears and an alarm is raised, the fire may already be spreading rapidly. The rule is simple: maintain a continuous fire watch, check the area also after the work has been completed, to ensure early detection and prevent escalation.” 

Pre-work inspections, supervision, and thorough risk assessment keep hot work under control. If’s Risk Engineers are ready to support your organisation’s fire safety planning and management, helping to prevent losses and manage risks with expertise and confidence.