In a paint and varnish manufacturing plant, a fire broke out at around 11 am in the liquid ink manufacturing workshop, close to a tank. The 3 technicians present contained the fire using fire extinguishers and a fire hose cabinet. The internal emergency plan was activated, staff were evacuated, and internal and external firefighters were called. When the external emergency services arrived, the fire had been contained.

The operator noted the presence of nitrocellulose dust in the protective housing of a knife gate valve, as well as the spillage of 1 l of monoethanolamine during the dismantling of a pump. A working group met up to determine what caused the outbreak of fire. The hypothesis of a reaction between the nitrocellulose and the monoethanolamine was dismissed following tests carried out in laboratories. The operator put forward several hypotheses, such as decomposition of the nitrocellulose dust present in the protective housing of the knife gate valve, or a mechanical hot spot causing heating of the valve combined with an accumulation of this dust in the protective hood of the pneumatic cylinder activating the valve.

The accident only produced minor damage to the knife gate valve and cables. The 250 l of fire extinguishing water placed in drums were removed to an approved waste treatment centre, along with the powder extinguisher dust. Production had been shut down on 2 tanks for 24 hours. The operator asked an external company to carry out an assessment on the valve. A new knife gate valve design was studied with a housing added and no longer closed to allow it to be cleaned and the nitrocellulose dust deposit to be removed and to allow preventive maintenance to be carried out on knife gate valves including visual inspection of mechanical parts and cleaning of the protective housings.