An inquest into a chemical plant explosion in July 2018 in eastern England heard testimony this week that a worker witnessed his father’s death in the disaster.
The blast at Briar Chemicals in Norwich, 100 miles northeast of London, killed Robert Cranston, 46, a contractor hired to do maintenance work, local media report.
His son, Owen Cranston, described the blast as “a very loud bang.”
“I can only describe it as looking like what you can see coming out of an aircraft engine on the runway before flight,” he said in a statement presented by the coroner.
A report issued by the Health and Safety Executive states that there was “some gas vapor directly around the vessel which ignited while the ‘hot works’ were ongoing. This then ignited the content of the vessel causing the explosion.
“Later analysis of the chemicals were carried out both immediately after the explosion and three days later. These tests show that there was an upper layer of Toluene in the vessel which was greater than 99% concentration.”
The senior Cranston worked at the plant for three years as a contractor involved in steel fabrication and pipe fitting. At the time of the blast, he was in replacing a steel ring on a large glass lined chemical tank, using both a grinder and welding equipment.
His son Owen had recently been hired as an apprentice. He worked with the same team as his father and was providing a “fire watch” during the welding on the day of the blast.
The younger Cranston told the coroner that the proper “hot work” permits to allow the welding were issued after safety checks and gas monitoring had been conducted. He watched from the ground as his father, wearing breathing apparatus, worked atop a scaffold to repair a water jacket.
His father’s coveralls were burned away by the flames, Cranston told the coroner.
Coroner Yvonne Blake told the jury at the inquest that at least 22 kilograms of Toluene, used in solvents, paints, glues and nail polish remover. It is produced when manufacturing gasoline and other fuels from crude oil.
Gas monitors specifically calibrated to detect Toulene would have triggered an alarm within seconds, Blake said. The configuration of the monitor used to check before the hot work began would have needed as much as seven minutes exposure to detect Toulene.
Gordon Wilcox, one of the supervisors who issued the “hot work” permit, testified that he thought the vessel involved had been washed out and free of any content that could create hazardous vapor.