A fire broke out at around 5:00 p.m. in a pit containing mixers at a factory where cork stoppers are made. The alert was given by a technician. The fire spread from the cork transfer pipe to a storage silo. Explosion conditions were reached, probably because the silo was being emptied at the time. The energy from the explosion dissipated via a flexible sleeve connecting the silo to a mixer, creating another fire. Both fires were rapidly extinguished by the nearby sprinklers. Fire-fighters arrived, evacuated the employees, extinguished the flames inside the silo, pipe and mixer, and secured the facilities. The accident’s consequences were limited to property damage and resulted in a partial shutdown of the company’s operations.

The operator engaged the services of a loss adjuster to determine the causes of the accident. The explosion and fire risks had already been identified in a hazard study that had been updated in November 2007 as well as in an ATEX study. The equipment that caused the fire (mixer, silo, etc.) had been identified as liable to cause an explosion. The accident may have been cased by an equipotential bonding failure combined with inadequate cleaning of the area where the first fire broke out.

The operator subsequently introduced a number of measures:

•  Deeper cleaning of the moulding areas.
•  Maintaining of equipotential bonds in good condition.
•  Improvement of the accident management system (internal emergency plan).
•  Purchasing of new ATEX equipment.
•  Training of employees in ATEX standards.