EMPLOYEE WAS REPAIRING THE SERVICE TRUCK. A PIECE OF ROCK FELL FROM BETWEEN THE ROOF BOLTS, STRIKING HIM ON THE BACK AND RIGHT RIB CAGE. THE INCIDENT CAUSED A FRACTURE TO A RIGHT RIB. THE INJU RED EMPLOYEE STARTED MISSING TIME ON 12/28/02 AND IS STILL UNDER THE DOCTOR'S CARE AT THIS TIME.