According to Queensland's Mineral Mines and Quarries Inspectorate, the worker was cleaning a port on a diesel burner, used for maintaining heat to the weir portion of a smelter furnace.
Contrary to regulations, he failed to isolate the fuel and air supply before starting, which led to fuel splashing over his PPE from the burner port, which soon ignited.
Colleagues rushed to extinguish the fire with their hands and then a bucket of water to no avail, with the man moved to a safety shower to dampen the flames.
An investigation by the inspectorate found there was no safety plan in place for regular burner port cleaning, with the task usually done without any isolation of the fuel and air supply.
Isolation was only possible through a control valve that was a distance away from the burner port, with multiple trips required for air and diesel adjustment.
The site also did not have an emergency response plan in place for fires.