Abstract: EMPLOYEES #1-4 WERE WORKING AROUND A COAL TAR PITCH TANK THAT CONTAINED COAL TAR PITCH HEATED TO ABOUT 450 DEGREES FAHRENHEIT. THE MATERIAL PRODUCES EXTREMELY FLAMMABLE VAPORS AT THAT TEMPERATURE. THE TANK HAS A LARGE COVER ON IT WITH A DOOR TO ADD COAL TAR PITCH. THE COVER IS NOT BOLTED OR OTHERWISE SECURED TO THE TANK. A 2 INCH STEEL PIPE IS PUMPED FULL OF COAL TAR PITCH FROM THE BOTTOM OF THE TANK. THE PIPE RUNS 65 FEET IN BOTH DIRECTIONS AND RETURNS TO A CONNECTING PART ON THE COVER. EMPLOYEES #1-4 WERE CHANGING THE SECTION OF PIPE THAT GOES INTO THE COVER. THE INLET WAS OPEN. EMPLOYEE #1 INADVERTENTLY PASSED A TORCH ACROSS THE INLET. THE VAPORS IGNITED. THEY WERE ALL STANDING NEXT TO THE TANK AND WERE BURNED BY FLAMES SHOOTING OUT FROM BETWEEN THE TANK AND ITS COVER.