EMPLOYEE WAS SWINGING BOOM ON BOLTER WHEN A PIECE OF ROCK FELL STRIKING HIM ON HIS ANKLE. CAUSE OF INJURY WAS AWARENESS AND NOT SEALING ROOF. COMPLOUANCE WITH RULES REGS WAS NOT A FACTOR, PERS ONAL EQUIPMENT NOT A FACTOR. THE ROCK STRUCK TOPOF HEAD, RIGHT SHOULDER, ELBOW, KNEE, AND THEN HIS ANKLE.