An explosion at a Cleckheaton factory is a timely reminder of why hazardous area heaters must be well maintained and suitable for the location in which they are used.
Several employees of the West Yorkshire firm had to be checked over after a sinter oven exploded, and the incident could have been much worse if they had not left the area moments before it occurred.
In the event, gasket sheets containing a flammable paraffin solvent were placed into a sinter oven before they were fully dry.
This meant there were still flammable fumes coming off of them and, when these met the electrical heating elements in the oven, the combination ignited with explosive results.
A HSE report on the incident notes that the oven’s temperature gauge was broken and other instrumentation had not been replaced in years – so it was effectively under manual control.
“It was an incident that could have, and should have, been avoided,” said HSE inspector John Micklethwaite.
“With any such industrial process, the fire and explosion risks must be fully assessed and then controls put in place.”
The mishap highlights how heating elements can ignite explosive vapours – an important lesson for all kinds of hazardous area heaters, which should not only be in place, but also in a good state of repair.