NORTH CAROLINA PUBLIC SCHOOL BUS LOCATED IN MECKLENBURG COUNTY WAS IN ROUTE WITH SIX CHILDREN AND A DRIVER WHEN THE DRIVER SMELLED SMOKE AND SAW THE SMOKE COMING FROM THE AREA BELOW THE STEERING COLUMN. THE DRIVER STOPPED THE BUS IN A SAFE AREA AND IMMEDIATELY STARTED EVACUATION PROCEDURES AND SUCCESSFULLY UNLOADED THE CHILDREN TO A SAFE PLACE. WITHIN APPROXIMATELY 5 TO 7 MINUTES AFTER EVACUATION FIRE WAS SEEN IN THE PASSENGER COMPARTMENT AND PROCEEDED TO SPREAD THROUGH OUT THE INSTRUMENT PANEL AREA AND THEN TO THE REAR OF THE BUS BODY. THE BUS WAS TOTALLY DESTROYED BY THE FIRE. INDEPENDENT INVESTIGATION WAS CONDUCTED WITH PRELIMINARY INDICATION THAT FIRE ORIGINATED IN THE ENGINE COMPARTMENT NEAR THE REAR OF ENGINE WHERE WIRING HARNESS IS ROUTED AROUND METALLIC HEATER SHUTOFF VALVE. THERE APPEARS TO HAVE BEEN AN ELECTRICAL SHORT WHERE THE INTAKE HEATER WIRE CHAFFED THROUGH THE WIRE HOUSING AND CONVOLUTED TUBING FROM RUBBING THE HEATER VALVE CREATING A SHORT TO THE HEATER VALVE WHICH IS SPECULATED TO HAVE STARTED THE FIRE. THE FIRE THEN BREACHED THE FIRE WALL THROUGH THE ENGINE ACCESS COVER LOCATED IN THE CENTER OF THE INSTRUMENT PANEL WHERE THE SMOKE WAS SEEN BY THE DRIVER. MULTIPLE BUSES IN THE NORTH CAROLINA FLEET OF THE SAME YEAR RANGE HAVE BEEN INSPECTED AND SIMILAR WIRE CHAFFING HAS BEEN DISCOVERED, HOWEVER AT THIS POINT NO ADDITIONAL FIRES HAVE OCCURRED. THE NORTH CAROLINA STATE FLEET IS CURRENTLY BEING INSPECTED BY THE LOCAL AGENCIES OPERATING THE BUSES TO HOPEFULLY PR