A fire broke out during welding operations on the water network of a laundry facility as the hose station network was not in service (outlet valve closed) at the time of the accident. The welding operations were being performed near the plant’s ceiling that was covered with hard-to-see textile dust. During the welding, a particle of molten metal was thrown against the ceiling, catching the dust on fire. The resulting flames quickly became uncontrollable. The fire spread to the metal beams nearby. An employee called the fire department while the welder attempted to bring the fire under control with a fire extinguisher from his lift as it started to move along the electrical cable trays. The fire was extinguished before the fire department arrived, but the thick smoke had been generated and an infrared camera had to be used to check for any existing hot spots.

A prevention plan and a fire permit had been established, although no specific measures were asked of the external company performing the work (dust removal or spraying operations prior to welding or grinding work); the foreman had requested that the subcontracting company use manual means to cut the existing extraction chimney would could contain accumulated dust and to supply a water-spray extinguisher. These recommendations were respected.

In its report following the accident, the external company indicated that all future operations at this site would require a fire permit followed by careful dusting of the very wide area surrounding the job site and wetting of the structures by spraying if the absence of electrical installation so allows. The Classified Installations Inspectorate requested that the operator submit a report relative to the origins, causes and consequences of this incident, and the measures taken and those to be implemented to prevent such an accident from happening again in the future.