A 200-litre leak of liquefied sulphur dioxide occurred on the flange joint of a tanker truck whose contents were being unloaded into a sulphitation tower typically supplied by a sulphur oven (undergoing maintenance). The technician cut the tanker supply line (pushbutton control). A leak remained unplugged on the stuffing box of one of the tanker valves. The bypass valve was turned on and the alarm was tripped.

The emergency response team proceeded by closing the valves and spraying the tanker. The French “red plan” for serious emergencies was activated. A plant employee, who had sustained local skin burns, remained hospitalised for 5 days; the protective suit he wore had been stored in non-airtight premises, where it was in contact with SO2. Within a 50-m radius, a total of 32 employees became slightly intoxicated, as did 11 fire-fighters, 4 of whom had more serious consequences. Use of an inadequate hose (for connection with the tanker flange) was the cause of this accident.