An employee was recently struck in the head by a rock in an underground mine in Victoria.
The employee sustained serious injuries to the head and shoulder, including a depression to the skull, requiring hospitalisation.
The injury occurred during an inspection of a stripping cut (or a ‘drag cut’) that was being made to an underground heading along the sidewall of an existing development.
The initial cut had been fired, bogged and scaled, and shotcrete was being applied as the first means of ground support within the development cycle.
Approximately 80 per cent of the shotcrete had been applied, however, the immediate left-hand pillar and a small area within the backs were yet to be shotcreted.
Ground penetrating support (such as rock bolts or split-sets) had not yet been installed, and shotcrete application was stopped to carry out an inspection.
While standing close to the transition line between supported and un-supported ground, the employee was struck by rocks that fell approximately 4.5 metres from the wall or backs.
The exact source location of the fallen rock is unknown, and upon investigation, several fragments of rock were located within the drop zone that had an accumulated weight of approximately 13kg.
“Entering or approaching areas that do not have ground support installed (unsupported ground) creates risks to the health and safety of employees, such as being struck by falling objects,” said Worksafe Victoria in a subsequent safety alert.
To reduce the risk of falling objects mine operators must:
perform a risk assessment to identify all potential hazards and assess the adequacy of all considered control measures, including exclusion zones and separating distances from unsupported ground
review and, if necessary, revise the need for and adequacy of overhead fall protection, should employees be potentially exposed to falling objects. This includes working in shafts