AT 11:30 AM, AN UNINTENTIONAL ROOF FALL WAS DISCOVERED BY THE BELT EXAMINER IN THE NORTH SUB-MAINS AT X-CUT #14. THE FALL WAS APPROX. 40'L x 16'W x 6'H. THE MSHA HOTLINE WAS CALLED AT 11:44 AM. THE FALL WAS LOCATED IN AN AREA WHERE 5' BOLTS HAD BEEN INSTALLED, PRIOR TO THE OPERATOR VOLUNTARILY USING 6' BOLTS.