2A 8NORTH EMPLOYEE HAD FINISHED INSTALLING A CENTER BOLT INT EH ROOF. HE LOWERED THE ATRS TO ADVANCE THE BOLTER TO THE NEXT BOLT WHEN A PIECE OF STONE FELL FROM THE ROOF AND STRUCK HIS FOOT. COMPLAINCE WITH RULES OR REGS. NOT A FACTOR. DID NOT INVOLVE EQUIPMENT OR MINIGN SYSTEM. JOB SKILLS, MINER PROFICIENCY OR PROTECTIVE ITEMS NOT A FACTOR. AWARENESS COULD BE A FACTOR.