The worker was helping to disassemble the hopper of a mobile crusher at a quarry in New South Wales and had removed one side of the machine.

He then started removing the rear plate, which was held in place by five bolts.

Mistakenly thinking the plate would be held in place by the two lower bolts, he removed the three top bolts, however, the plate was hinged and swung down into his shoulder.

The worker suffered soft tissue injuries and the suspected spinal injury.

According to the NSW Resources Regulator, supervisors should make sure workers had access to procedures before starting tasks, and understood the risks and controls associated with that task.

Workers also had a legislative duty to care for their own health and safety and that of others, with one of those duties requiring them to cooperate with any reasonable policy or procedure.

The regulator said procedures were in place to help protect workers from injuries or illness, and where a procedure existed for a particular task, workers should follow it.

"Any deviation from a procedure should first be discussed with a supervisor and appropriate risk control measures put in place," the regulator said.