The dragline operator was not aware the cable tractor was operating so close by and did not realise the machines had collided until the cable tractor operator extricated himself from his damaged machine and operated the dragline warning siren.

“Since a safety newsflash on dragline and cable tractor interaction was sent to surface coal mines in July 2015, another serious interaction has occurred,” the Department said in its most recent safety alert.

“Fortunately, the cable tractor operator was not injured.”

Possible collision between draglines and cable tractors, or any machinery operating within the swing radius of an operating dragline, was a potential hazard.

In the last two years, 11 collisions between draglines and cable tractors have been reported to the Mines Inspectorate -- six of these since January 2015.

“The risk from draglines to pedestrians and to cable tractor, dozer and service vehicle operators is largely managed through a series of administrative controls,” the department said.

“Few if any higher order controls (such as elimination, substitution or engineering controls) are in place.”