At around 9:30 a.m., a fire broke out in the extraction system of the drying area at a wooden furniture factory. The fire spread first to the cyclone dust collectors and then on to the 25-m-high sawdust storage silo with a capacity of 400 m³. The operator shut down the production line. Three nozzles and seven hoses were used to contain the fire. The operator opened the extinguishing ring and unloaded the silo. The fire was extinguished at around 3:45 p.m. The person in charge of the factory returned part of the dryers back on without first consulting with the commander of the rescue operations.

The dust extraction system caught fire due to excessive build-up of sawdust in its piping and the system’s design, which promoted zones of turbulence within the pipes. An inspection carried out by the operator revealed an accumulation of sawdust in the elbows and in runs where the piping changes direction. Upstream overheating could have easily spread via the extraction piping. In addition, the spark detection and extinguishing system failed to operate because it was incorrectly positioned on the piping. The lack of a decoupling system on the extraction system upstream of the cyclone dust collectors did not stop the combustion.

A number of fires had occurred on this system in 2016 (ARIA 48244, ARIA 47868), 2009 (ARIA 35722), and 2010 (ARIA 39247). The operator plans to implement several measures:

• possibility of fitting a decoupling system between the extraction system and the cyclone dust collectors;
• possibility of installing a Windsifter upstream of the dust storage silo;
• complete overhaul of its GreCon spark detection and extinguishing system;
• repair and replacement of  damaged equipments ;
• modelling of the piping to optimise and control extraction;
• carrying out monthly preventive maintenance on the water injection system.