At 13:19 fire broke out in a pyrotechnic establishment at the end of the sieving cycle of a boron- and potassium-nitrate-based compound when the worker entered the manufacturing cell after the sieve had been switched off and the power supply to the cell cut. The worker suffered seriously burns to the face, torso and arms despite wearing personal protective equipment (cotton underwear, overalls, leather gloves with fireproof cuffs, dissipative safety shoes). Three colleagues that were close by took care of the victim (fire blanket and then an emergency shower) before he was transferred by fire fighters to the burns centre of Toulouse Hospital. The worker died a few weeks later.
The operator’s security committee analysed the materials, the material, the protective equipment, the operating procedure, etc. The raw materials and those manufactured were found to comply with requirements, the worker was qualified and specially trained for the manufacturing process in question, the manufacturing cell was in good shape. On the other hand, all parts of the sieve fastening system were not found and the metallic pieces (hooks and pins) and rubber bands that composed it were in bad condition. The operator concluded that the compound had been initiated as a result of the shock caused by the sieve falling onto the compound. During or at the end of the sieving cycle, two elements of the fastening system of the two sieves broke (or became loose) and the sieves were released abruptly and hit the 400 g of compound in the lower receptacle. The combustion of the compound spread to the 600 g of compound placed temporarily on the table of the cell.
The operator forbade the intermediate storage of active material in rooms with armoured doors, added to the operating procedure a requirement whereby the fasteners must be checked every day and instructions on what to do if there are doubts or the fasteners must be changed, installed a time switch to delay access to the armoured rooms, and equipped each armoured-doored room with a video surveillance system.
