Last reviewed 20 September 2021

In July 2018, a maintenance contractor was carrying out repair work on a mixing vessel during a planned period of shutdown maintenance at Briar Chemicals Ltd.

It is thought that his welding torch or grinder accidentally ignited flammable Toluene vapour inside the vessel, which should not have been present when the work was started.

Robert Cranston suffered extensive blast injuries and burns and died in hospital. After an 11-day inquest into his death, in December 2020, a jury decided that it had been accidental.

While his family had wanted a verdict of unlawful killing, Norfolk area coroner Yvonne Blake directed the jury that they could only decide if it was a case of accidental death.

An investigation by the Health and Safety Executive (HSE) found that two damaged valves situated above the vessel in the Toluene supply pipe, were leaking.

Operatives had been instructed to transfer a large quantity of Toluene from one storage tank to another via this pipe which allowed additional flammable liquid to leak into the vessel which was supposed to be empty and clean.

Norwich-based Briar Chemicals has now pleaded guilty in Chelmsford Magistrates Court to a breach of Regulation 5 of the COMAH (Control of Major Accident Hazards) Regulations 2015 and has been fined £1million.

HSE inspector Frances Bailey, who led the three-year investigation, said: “This was a complex and highly technical investigation, due to the chemical hazards on site and the number of underlying issues which combined to cause the explosion. HSE hope that this case helps to communicate important safety messages to wider industry so that other fires and explosions are prevented in future.”

Any company handling or storing flammables should consider the potential risk of fire and explosion and ensure they have robust procedures in place to minimise and control risk at all times, including during planned maintenance work, she concluded.