At around 5:00 p.m., a fire broke out in a portable mixing tank containing 400 litres of a mixture of solvent and nitrocellulose at an ink and paint manufacturing company. Alerted by the smoke, an employee activated the automatic fire suppression system and evacuation alarm. The internal emergency plan was implemented. Two explosions were heard. Upon arriving, the firefighters saw that the fire had been extinguished by the suppression system. They protected the nearby tanks of solvent in the workshop but had difficulty evacuating the smoke.

The smoke released by the fire irritated the eyes of six firefighters and one other person. Part of the facilities were gutted by the fire. The firewater was contained in a retention pond on the site.

A technician was in the process of loading chips of solid ink (nitrocellulose-based pigmented resin) into a mixing tank containing 400 l of solvents when he saw a large amount of smoke rising out of the tank.

The most likely hypothesis is that an insufficient amount of solvent in the tank during mixing caused the nitrocellulose to heat up and ignite. A report generated by the computer-aided manufacturing system confirmed the lack of solvent; however, this was not confirmed by the technician.

A low-level sensor ensures that a sufficient amount of solvent is in the tank before chips may be added, but it had been disconnected due to faulty operation.

There were other questions as well, particularly about whether the mixing speeds were correct and how the manufacturing temperature was monitored.

The inspection authorities for classified facilities conducted an inspection visit the day after the accident and suggested that the prefect issue a draft decree ordering that the facilities be made safe again before being restarted.