In this post we will look at some of the common hazards encountered when performing hot work, as well as some that you might not expect. Read below to see our 6 steps to improving safety when performing hot work.
What does the term 'Hot Work' cover?
Hot work is any work task that could produce heat, friction, sparks or flames. It includes welding, soldering, braising, cutting, grinding, sawing and the use of heat guns. Hot work accidents can result in injuries to individuals such as burns, as well as widespread fires causing major damage.
In the worst cases, badly managed hot work can result in explosions and fatalities.Some organisations include other work within their hot work permit system which although not in itself a fire or explosion hazard, could undermine safety.
Many hot work accidents have occurred when people have carried out hot work on old fuel cylinders or tanks, either as part of waste processing, or as refurbishment. These containers are rarely completely empty, and a small residue of fuel is enough to create a significant fire.
But not all hot work explosions are in industries with obviously flammable gases and liquids. The CSB in the USA identified hot work explosions resulting from flammable gases produced by mixes of cardboard waste, fish waste and even the waste from washing potatoes. In all cases organisations did not test for gas before hot work started because they assumed these slurries were harmless.
Key Combustion Hazards
Even otherwise low risk organisations need to consider how they manage hot work during refurbishments and building projects. Zurich Insurance describe three fires in schools, all started because of a failure to manage hot work properly.
In one fire, the key combustion hazards had not been identified, and therefore when the plastic tarpaulin caught fire, the flames spread quickly to the other combustible materials around the work area. There was no fire extinguisher nearby, which might have been effective if it had been used immediately on a small fire. In the second case the work appeared to have been successful, but no one was asked to check the site for the hour after the work finished. By the time the fire was discovered, it was too late.
In both these cases Zurich concluded that had an effective hot work permit system been in place, the fires could have been avoided, or the impact of them could have been reduced. In a third case there was a permit in place – but it was kept in the contractor’s cabin. The person who completed the permit as a “box-ticking exercise” was not the person doing or supervising the work, and the team doing the work knew nothing about the controls required.
These cases could have been avoided – or the impacts reduced – by applying these 6 steps:
Can the job be done without hot work? Can you buy in parts ready welded or ready cut? Can cold cutting techniques be used? Can smoke detectors be replaced with heat detectors which won’t need to be deactivated for work creating dust or fumes?
Identify & Manage hazards
Consider the work location. Can the work be done in an area set-up for hot work? What sources of combustion, ignition and oxygen are in the area? How can these be controlled? In the first school case, some old-fashioned tidying up before they started would have meant there was less fuel to stoke the fire. In more complex cases, systems need to be purged, or sources of ignition isolated.
Assign competent people
Many accident reports on hot work explosions mention the lack of adequate training given to the people doing the work. They need to have been trained to identify the hazards, as well as on how to do the work safely.
Because hot work can have several essential controls it is not enough to hope that people will remember what to do, based on training that could be several years old.
A permit reminds people what needs to be checked before, during and after the work. Often it requires people with competencies in different areas to sign off that specific checks have been made. Has the area been cleared of combustion hazards? Has the air been tested for flammable gases? Has the right fire extinguisher been provided?
Permits must be authorised by someone with the competence to check that the controls are in place. In most cases, it is not advisable for people to sign off their own permits on the work they are doing. Too often permits are signed off by someone sitting in an office without visiting the work area to confirm controls are in place. A Permit to Work software can help you to control permit issuance and acceptance and keep track of everyone involved in the project.
Permits must be visible and shared by everyone involved in the work. The person managing the work on behalf of the school in the Zurich cases might not have understood all the controls needed, but they could have challenged the contractors before they left the site if they had read the permit requirement for a fire watch. Its a good idea to use a software that stores all permit-related documentation in one place, so the approriate people have access to all relevant information.
Lack of visibility of permits was one of the contributory factors to the explosion that caused the deaths of 167 people on Piper Alpha in 1988.
Hot Work can be dangerous to those perfroming it and can have disasterous consequences if the appropriate permit systems are not in place. The Engage EHS Permit to Work Module lets you create, issue and manage your permits with ease, for all manner of hazardous works.