In a raw materials warehouse of a chemical factory manufacturing organic chemicals, a series of explosions leading to an intense fire spreading to an external drum storage area. Near an adjacent steam condensate pipe, 2 or 3 containers (2 tonnes) of azodiisobutyronitrile (AZDN) break up and released into a store reserved for oxidising materials (specially sodium persulphate). Due to its incompatibility with AZDN, they ignited. 33 people, including 3 residents and 30 firemen/policemen are taken to hospital. Approximately 2000 local residents are confined to their houses and residents immediately adjacent to the warehouse are evacuated. Roadblocks were put-up around the factory. Firewater run-off caused significant river pollution killing 10 000 fishes. The total cost of damage was estimated at £4.25 million and substantial indirect costs were incurred.
A malfunction of the steam heating system or operator error caused the condensate pipe to be hot. The heating effect caused the AZDN kegs to rupture. The investigations by the HSE revealed that this accident is an example in where a number of apparently unrelated errors, omissions resulted in a major fire. The segregation of incompatible substances (AZDN kegs were stored in the same section as oxidising substances), the warehouse management system, the safe operating procedures, the fire detection and fighting methods (the warehouse were not fitted with adequate smoke detection and fire fighting facilities), the emergency plans (50 minute delay before the fire occurred and the emergency services informed) should be revised.