Fifty years ago, at 4.53pm on Saturday 1 June a devastating explosion levelled a chemical plant near the small English village of Flixborough, not far from Scunthorpe. The explosion killed 28 people working at the Nypro site and seriously injured 36 more. Two hundred houses were destroyed and another 1000 damaged, with the blast heard 30 miles away in Doncaster and Grimsby.


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The Flixborough Disaster was a wake-up call for industry on process safety

The explosion was the result of an improperly constructed bypass on a reactor. The Nypro plant was using cyclohexane to produce caprolactam – a commodity chemical mostly turned into nylon. When the bypass pipeline broke, tonnes of cyclohexane leaked out and ignited, resulting in a fireball that rose hundreds of feet into the air.

Details of the disaster that came from one employee of the Nypro plant that Chemistry World spoke to make for harrowing reading. Others declined to talk to us – even all these years later, the memories are still too raw for some.

The story of the Flixborough disaster will sound eerily familiar to many, echoing as it does reports that have followed other accidents. It’s a tale of incuriosity in the face of unsafe engineering, a lack of appropriate expertise in critical areas and a failure to respect the design precepts that informed the facility.

Despite the investigation highlighting failings at Nypro there was no suggestion that management had broken the law. No one was held accountable for the deaths that resulted. The health and safety act came into force later that year and included unlimited fines and prison sentences for those who fail in their duty of care to employees.

The economics of caprolactam synthesis mean production has now moved to other areas of the world – Nypro rebuilt the plant at Flixborough but falling demand meant it closed in 1981. But the lessons from Flixborough have travelled too and helped inform safety around the world. This means it’s best practice to keep non-essential personnel away from a plant so, should the worst happen, they are safe. Other important recommendations from the investigation include that any modifications made to a plant should match the original specifications and be checked by qualified personnel.

Huge chemical disasters, such as Tianjin in 2015 or Beirut in 2020, that make headlines continue to occur. But, it is to be hoped, each time safety is improved, new measures put in place and lessons learned. Improvements in safety is a step-by-step process building on past efforts. Failure to learn is costly to all involved in an industry that the world cannot do without.