A rear dump truck was hauling rock down a steep and winding road at a mine. The operator had selected fourth gear to travel down the ramp, when a brake failure caused a runaway. Both the retarder and service brake failed to have any effect.
The driver applied the emergency brakes before driving the truck into an emergency escape ramp. The right hand side wheels veered off the edge of the ramp due to a design failure and the truck overturned and rolled into a drain.
The operator was restrained by a seat safety belt and was uninjured.
In the alert, the Inspectorate recommended for dump truck operators to carry out pre-start brake checks, and to utilise preventative maintenance scheduling. Operators should also be trained in the use of retarders and emergency brakes.