He survived the 10 August, 2017 incident, but received serious burns to the face, neck, torso and arms.

The NSW Resources Regulator has released an investigation report criticising the BHP Muswellbrook mine and contractor, Otraco International owned by Downer EDI, for leaving contract tyre handlers at risk by failing to establish safe refuelling procedures.

The investigation identified the use of petrol adapters since 1995 which were not fit for purpose.

“The fact that the adapter was kept at the mine for such a long time demonstrates that there was a deficiency in the (mine’s) inspection regime for the refuelling facility,” the investigation report said.

The 2017 incident occurred in part because Mount Arthur mine refuelling service cart operators were not aware they were obliged to refuel the contractor’s tyre handlers, and the tyre handlers believed their use of the refuelling area was authorised.

The confusion, caused by a failure to communicate between the mine and the contractor, meant tyre handlers waited up to two hours for refuelling by mine service carts, with some contract workers saying the delay was up to five or six hours.

“The mine’s service cart operators assigned a very low priority to requests made by the contractor to refuel its tyre handlers. Their practice was to prioritise refuelling the mine’s equipment in production,” the Resources Regulator found.

A consequence was contract tyre handler workers were not trained to refuel their machines in the refuelling area but the practice was “normalised”.

The 29-year-old contract worker who had worked in mines for eight years was in an acting position for the day when he was asked to refuel a tyre handling machine. He selected an 800 litres per minute adapter rather than a 300 litre one, because the fittings were the same colour and poorly labelled.

Within seconds the fuel nozzle was ejected and “flung around under pressure”, with diesel fuel flowing at a peak of 791 litres per minute after 18 seconds and splashing onto the worker. The investigation report said the worker had the fuel hose over his shoulder at one point to try to arrest the flow.

A “flame flashed back towards the worker” less than 30 seconds after the incident started, and after diesel flowed from the refuelling area to the tyre handler’s engine area and came in contact with engine parts estimated to be more than 300 degrees Celsius.

“The worker’s hair and the sleeves of his long sleeve work shirt caught fire,” the report said.

The worker ran for a drain and extinguished the fire by putting his head into mud. He was flown by rescue helicopter to Royal North Shore Hospital’s burns unit and continues to receive extensive treatment including skin grafts for burns to 8 per cent of his body, including full thickness burns to 5 per cent of his total body surface area.

The Resources Regulator said mine refuelling service cart operators denied issuing instructions to contract workers to use the refuelling station, and over half had seen the contract workers use the refuelling area. It found mine service cart operators “encouraged” contract workers to use the refuelling area. 

“Having regard to the size of the workforce at the mine and the large volumes of hydrocarbons stored and used at the refuelling facility, an effective broad-brush risk assessment could have identified all risks associated with the facility’s operation,” the Resources Regulator found.

A BHP spokesperson said Mount Arthur Coal fully participated in the regulator’s detailed investigation and welcomed its involvement.

“Mount Arthur Coal also conducted its own review of the fuel delivery systems at the mine and we have incorporated learnings from that review into our processes and training programs for all operators. Safety continues to be our number one priority,” the spokesperson said.