EMPLOYEE STANDING UNDER SUPPORTED ROOF WAS WATCHING THE ATRS GO UP TO THE ROOF. A LARGE PIECE OF ROCK FELL FROM THE UNSUPPORTED AREA LANDING ON TOP OF THE CANOPY OF THE BOLTER BOUNCING BACK AN D TURNING VERTICAL PINNING HIS ANKLE. CAUSE WAS SAFETY AWARENESS. COMPLIANCE WITH RULES/REGS WAS NOT A FACTOR, SAFETY EQUIP NOT A FACTOR, MINER PROFIENCY/ATTITUDE COULD BE A FACTOR, MINING EQ