On February 3, the operator was attempting to clean build-up off a screen using a high-pressure water cleaner.
He was working in a cramped area when he tripped and dropped the lance. The jetting gun failed to automatically shut off.
This allowed high-pressure water to hit the operator on the forearm.
The operator was transported to medical aid where his injury was identified as a fluid injection.
The investigation identified that the working area was restricted, cramped and that the equipment was not fitted with an emergency stop or shutdown function.
Also, the automatic shut-off function on the jetting gun failed, possibly due to contamination from supply water being unfiltered. Quick-release couplings on the jetting gun and flexible hose were not capped during storage.
No safety observer was present, the working area was not barricaded, and the operator was not wearing the correct personal protection equipment.
The Mines Inspectorate said high-pressure water-jetting equipment should be defect free, fit for purpose and fitted with all recognised safeguards.
It should also be subject to pre-use and periodic equipment inspections to ensure it remained safe to use. Any area in close proximity should be barricaded to prevent inadvertent interaction of high-pressure fluid equipment and people.
“All operators and assistants of high-pressure water-jetting systems should be trained in the safe use of the equipment by competent people in accordance with AS 4233.1:2013,” the inspectorate said.