An explosion occurred in a dust filter of a waste paper treatment installation at a printing factory. Flames spread through the ventilation ducts and generated fires on a stitching machine in a workshop (rapidly controlled), a cyclone and a silo filled with shredded paper. Given the risks of the fire spreading to the workshops and houses very nearby, around fifty fire-fighters carried out a major hydraulic operation. The factory was evacuated and the electricity was cut off on the site. Due to the undersized vents and the risk of the silo exploding due to the vaporisation of the fire extinguishing water, the fire-fighters drilled vents in the top part of the storage area. To prevent any risk of flashbacks, and protected by a hose, they opened the 2 lateral inspection hatches located half-way up the silo and then flooded the interior of the storage area. The silo had no rapid emptying device which would have made it easier to extinguish the fire.

The presence of pieces of paper floating on the River MARMANDE led the emergency services to deploy a preventive boom. Two fire-fighters were slightly poisoned during the intervention. The dust filtration and chip cyclone systems were not working. Some of the flooded workshops were shut down.

An extraction hood and vent located at the cyclone-dust removal system intersection were two possible causes identified during the investigation. The inspection authorities recommended that the Prefect order a supplementary hazard analysis on the risks of fire and explosion in ventilation and filtration systems.