During the night of 6 to 7/08, an odour of tetramethylpropylene amine (CX 209) was detected in a chemical plant. This flammable and toxic substance was leaking into a retention system due to the failure of a glass level indicator on a storage tank and an isolation valve being mistakenly left open technician. The staff present, put on self-contained breathing apparatus before attempting to reseal this level valve, activated the sprinkler system over the storage area and unit as a precaution, diverted the stormwater network to the fire extinguishing water tank and neutralised the effluent collected in the retention system. The neutralised waste was then stored in a tank pending its destruction.

No rupture of this type had previously been noted on the site. The Fibreglass housing protecting the level, which was still in place after the accident, showed no trace of impact and no work was being carried out nearby that was likely to generate stresses on the equipment. The cause of the failure is unknown. No human or environmental consequences were reported. Although the retention system was inspected regularly, a sampling campaign in the piezometric wells launched on the day after the accident was continued for 15 days. However, none of the analyses revealed any anomalies.

Further actions are envisaged, such as the replacement of the level in the tank involved and the last 2 glass level indicators present on the site by the end of 2004.