At 11:45 am in a non-ferrous metals production plant, the technician assigned to the ingot brushing machine noticed flames on the brushing particle filtration installation located just in back of a protective partition wall. He activated the machine’s emergency shutdown switch and informed a fellow team member. The 2 employees used dry sand to douse the flames. Five minutes later, without being able to extinguish the fire, they called another employee for backup and, in compliance with plant procedures, alerted the local fire station and shut off all energy supply to the facility (in particular electricity). When the public firemen arrived at 12:05 pm, the fire had already been put out.

Fine zinc particles accumulating after insufficient cleaning of the filter retention tank, which was not readily accessible, caused this fire outbreak. The installation was restarted later the same day following a thorough cleaning and repairs to the electrical circuit, which had melted during the fire.

Subsequent to this accident, the operator implemented several remedial actions, namely: a thorough cleaning once a week (instead of the previous once a month) and partial cleaning every day; plant procedures detailing both the partial and complete cleaning tasks; controls performed by the workshop foreman to ensure cleanliness of the equipment following each intervention; verification of filter cleanliness prior to each brushing; availability of a handling system adapted to facilitate access to the filter retention tank; and modification of the protective partition wall to contain flying sparks.