1st Surface Ltd has been fined £9,000 and ordered to pay £2,571 in costs after two men sustained serious burns while attempting to use an old air shelter as a makeshift furnace to burn garden waste.

The pair were working for the Surrey-based company to extend and resurface a tennis court when the incident occurred on 25 January 2011, and Westminster Magistrates’ Court heard that as part of the initial preparation work they needed to clear an area of overgrown garden where the new court would go.

It was revealed that they gathered sufficient waste to fill around five skips, but no such method of disposal was available to them and they had not been given any clear instruction on how to safely dispose of the waste.

They decided to use an air raid shelter in the garden, which was situated in the area of ground to be cleared and was to be demolished anyway, as a furnace to burn some of it.

The Court heard that one of the workers entered the shelter via a chimney at the top, placed some kindling inside to get the fire started and poured on petrol to act as an accelerant. He then left the shelter and his colleague threw a lit taper into the shelter to start the fire.

However, the petrol vapour that had accumulated within the shelter exploded and both men who were standing on top of the shelter, received burns to their faces, and as a result were hospitalised for several days.

The Health and Safety Executive (HSE) investigated the explosion and found 1st Surface Ltd had failed to properly assess and plan the waste disposal aspect of the work.

It said that if the company had provided skips prior to the clearance starting, the two workers would have had no need to burn the waste. The system they chose was extremely high risk and they were unaware of the significant risk posed by petrol vapour, especially when allowed to expand in a confined space.

1st Surface Ltd pleaded guilty to breaching Section 2(1) of the Health and Safety at Work etc Act 1974, and as a result were handed the fines.

Following the hearing, HSE Inspector Kerry Williams, said:

“This incident could easily have been prevented with a minimal amount of planning and preparation.

“Many people do not recognise the explosive risk presented by petrol vapour, and as the men had been provided with petrol for other purposes their employer should have made the risks clear to them.

“The underlying issue here is that 1st Surface Ltd should have agreed and communicated a safe system of work in advance. Had the company done so, they wouldn’t have needed to take matters into their own hands in the way they did. Ultimately it was the company’s responsibility to keep them safe and ensure they worked in a sensible, carefully-controlled manner.”