At around 6 p.m., in a waste recycling centre, a fire started on a hydraulic compaction press. A large amount of smoke was seen, but without visible flames. The fire alarm went off. Thirty staff members were evacuated from the site and the power supply to the press was shut off. Two employees attempted to put out the fire with the hose reels and opened the smoke vents. Materials handling equipment was used to remove flammable materials located near the seat of the fire (bales of cardboard, bulk cardboard). A retention system was put in place. Upon arriving at the site, the firefighters set up a nozzle to replace the hose reels. The intervention was completed at around 7 a.m. Inspections were carried out by thermal cameras to ensure that no hot spots were present.

The unit involved was cleaned and dried, and activity resumed at 8 a.m. The production facility was not damaged, except for the power supply cables of a motor. The extinguishing water, collected in the press’ conveyor pit, was pumped out by a specialised company. The bale where the fire started and the two adjacent bales were quarantined on site for monitoring purposes.

The fire had started in the confined space of the press channel. The batch to be pressed consisted primarily of household cleaning aerosols, aluminium boxes and a few undesirable elements (plastic films, food boxes, etc.) resulting from sorting errors.

According to the facility operator, the event may have been caused by:

• a mixture of incompatible gases during the pressing of the aerosols and aluminium containers. The metal-to-metal contact within the press may have been a source of ignition (sparks).
• the presence of a lighter refill or hairspray propellant type liquefied flammable gas in the aluminium packaging. During the pressing operation, the increase in pressure would have released energy, shifting the gas into its flammability range.

Following the accident, the operator took the following actions:

• review of the aluminium/steel pressing guidelines and the search for an alternative baling solution for materials;
• check the correct operation of the equipment each morning before the shift begins;
• keep waste stocks (bales, bulk) low and ensure daily storage/cleaning of units;
• set up intervention sheets in the form of checklists for employee.