EE DECIDED TO HELP THE SUPPLY PERSON GET THE DROP WHEEL UP OF A SUPPLYCAR BY RELEASING THE LOCKING DEVICE. HE DID NOT KNOW HOW THEY WORKED OR HE DID NOT OBSERVE THAT THE SCOOP WAS NOT HOLDING UP THE CAR. WHEN THE LOCKING MECHANISM RELEASED THE CAR CAME DOWN ON HIS FOOT. CAUSE OF INJURY WAS KNOWLEDGE & AWARENESS. MINER KNOWLEDGE, MINING EQUIPMENT/SYSTEMS A FACTOR.