EE WAS REPOSITIONING HIS BOLTER ALONG THE RIB IN ORDER TO INSTALL A ROOF BOLT IN A ROOF STRAP. AS HE TRAMMED THE BOLTER FORWARD THE CANOPYS TRUCK THE RIB CAUSING A SECTION OF THE RIB MEASURING APPROX. 10'L X 16"" HIGH X 1-12"" THICK. TO FALL OUT OF THE RIB FROM 5' ABOVE THE MINE FLOOR. THE RIB ROLL STRUCK HIM FROM BEHIND AND FORCED HIS FACE AGAINST THE MACHINE RESULTING IN HEAD AND F