SHOVEL OPERTOR WAS WALKING OUT OF THE CONTROL ROOM IN THE HOUSE WHEN HE STEPPED OFF THE LAST STEP IN OIL AND FELL ON HIS BACK. HE WAS HOLDING THE HANDRAIL WITH HIS RIGHT HAND AND HIS LEFT ARM HIT THE HOIST BRAKE IN AN ATTEMPT TO CATCH HIMSELF. HE WAS TREATED BY A PHYSICIAN AND TAKEN OFF WORK.