AN UNINTENTIONAL ROOF FALL MEASURING APPROXIMATELY 7 FEET HIGH, 20 FEET WIDE & 25 FEET LONG OCCURED IN THE INTERSECTION OF THE #3 ENTRY, PILLAR #152, SPAD 8724 ON THE 9 RIGHT SECTION. NO INJUR IES OR DISRUPTION OF VENTILATION RESULTED FROM THE EVENT. THE EVENT DID NOT OCCUR IN ACTIVE WORKINGS.