WHILE ROOF BOLTING THE DRILL STEEL BROKE LEAVING A PORTION IN THE ROOF. THE EMPLOYEE REACHED TO MOVE THE STEEL GUIDE OUT OF THE WAY TO BETTER REMOVE THE STEEL FROM THE ROOF. JUST AFTER THIS IT FELL STRIKING THE BACK OF HIS LEFT HAND, FORCING HIS HAND DOWNWARD TO THE ROOF BOLTER HEAD, PINNING HIS HAND BETWEEN THE END OF THE DRILL STEEL AND THE BOLTER HEAD.