In a recent accident, an experienced mineworker travelling out of the mine towards the end of an extended night shift apparently stumbled as he tried to get off at a man-riding conveyor at a side-dismount alighting platform. He struck either the edge of the platform or part of the conveyor structure and sustained two broken ribs and a punctured lung. The injured person fell back onto the conveyor and passed beneath the safety gate beyond the alighting platform. Fortunately, there were two other people with him who were able to stop the conveyor before he came to more serious harm.
The failure of safety gate to operate because of its position had no bearing on the accident or the injuries, but the fact that the injured person was able to pass beneath it causes concern. The safety gate was positioned just over 500mm above the middle of the conveyor to allow lumps from two developments and a dint to pass through without activating the gate, but this is easily high enough to allow a person riding in a prone position to pass beneath it without causing it to operate.
There was a similar incident in 1992 when for some reason another experienced mine worker failed to alight from a manriding conveyor, passed beneath a safety gate and was killed. This accident stimulated research into safety devices based on personal transponders designed to stop a man-riding conveyor in the event of someone overshooting an alighting platform.
There is clearly an increased risk to persons riding conveyors where a safety gate is set high to allow the unimpeded passage of minerals to the extent that it will also allow a person in a prone position to pass beneath it without operating. This risk needs to be reduced. Mine managers and engineers must therefore ensure that they do all that is reasonably practicable to provide an effective means of stopping any man-riding conveyor, whether or not it is also used for conveying minerals, in the event of someone overshooting an alighting platform and remaining in a prone position on the belt. Owners of mines where man-riding conveyors are used should satisfy themselves that appropriate action has been taken.S P Wing