In an explosives manufacturing facility, a technician was cleaning a production area within a unit that had been shut down a few hours prior (at 3:20 am). Around 10:15 in the morning, the technician removed the lid on the nitrocellulose measuring device and placed it on the floor when a flash occurred. The automatic drowning mechanism was activated upon infrared detection and the fire was quickly controlled. The technician sustained 2nd-degree burns on the forehead and received care by the emergency medical team called to the scene by the operator.

The operator laid out 2 possible scenarios when the lid was placed on the floor: initiation of nitrocellulose traces on the lid by means of a shock; or initiation of ethanol vapours and/or nitrocellulose fibres imbibed with alcohol by means of static electricity discharge. The operator proceeded by implementing the following measures:

• reduction in nitrocellulose diffusion by decreasing the clearance between machines;
• spraying of the room in order to maintain the nitrocellulose in a phlegmatized state (search for a system);
• modification of intervention conditions in the room (ventilation prior to entry and wetting of the floor and equipment);
• renewed emphasis on risk awareness among personnel;
• completion of an audit on the risks of static electricity in the workshop.