Operators in a phosgenation workshop at a chemical plant were rinsing a tank with octanoyl chloroformiate, unaware that workers from an external company were working nearby; 40 to 50 kg of chloroformiate poured out of an open line and spilled on to the floor, resulting in splashing and gaseous releases associated with the hydrolysis of the chloroformiate.

One of the subcontractors was sprayed on an arm and leg, and 3 other experienced discomfort. The alarm was sounded and rinsing operations were suspended. The 4 injured individuals were taken to the plant’s nursing station, then hospitalised for further examinations as a precaution. They were able to return home the following day.

A pipe had been cut on the circuit undergoing modification in order to install connectors. A prevention plan had been established for the work being conducted, the unit had been drained and a workshop operator had helped to open the circuit, although the equipment had not been properly locked out.