The explosion, which happened the day before children returned to Greetland Academy after the summer holidays in September 2011, blew out the boiler house door toward a paved area and the school playing field.
Two local neighbours in School Street heard the explosion and rushed to the school where the teaching staff were having a training day. Fortunately there were no injuries.
The Health and Safety Executive (HSE) was notified and discovered Marshall Gas Services Ltd, based in Greetland, had been on site the same day to service three boilers and other gas appliances, and had held a contract to carry out annual inspections and services there for at least ten years.
After investigating, HSE prosecuted the company at Halifax Magistrates’ Court on 8 June 2015 after finding that despite the servicing contract, the boiler showed all the classic signs of poor maintenance, including excessive rust and debris, and had become increasingly dangerous.
The court heard that on inspection by HSE gas specialists, the burners produced a significant amount of internal corrosion and the gas injectors were very dirty, which significantly reduced the aperture size.
The restricted gas injectors prevented sufficient gas getting to some of the burners to allow them to be cross-lit when turned on. Unburned gas then passed into a combustion chamber and created an explosive atmosphere.
HSE’s investigation showed the build-up of debris and the partial blockage of the injectors would have occurred gradually over a period of time, and that the levels in the boiler were not consistent with a regular annual service regime.
Marshall Gas Services Ltd, of West Vale Chambers, Stainland Road, Greetland, Halifax, was fined £13,000 and ordered to pay £35,699 in costs after admitting a breach of the Health and Safety at Work etc Act 1974.
After the hearing, HSE inspector Jackie Ferguson said:
“This was an entirely preventable incident. It was pure luck no children were around at the time as the boiler house was close to the school playing field and access routes for staff and pupils alike.
“Marshall Gas Services displayed a reckless disregard for the safety of the community, and these young children in particular, and the outcome could have been far worse.
“On the wider issue, all companies who carry out gas work must comply with their legal duties and responsibilities. Experience has shown that some operating in the gas sector are prepared to breach regulations by undertaking gas work while not on the statutory register and without the necessary competency. There are also instances of registered engineers operating outside the scope of their competency.
“HSE will continue to undertake effective regulation and enforcement of this industry where we find negligence and safety failings.”