Abstract: DURING THE MORNING OF AUGUST 16, 1984, EMPLOYEE #1 WAS CUTTING HOLES INTO PIPES FOR THE INSTALLATION OF THERMOMETERS. HE WAS USING AN OXYGEN AND ACETYLENE SYSTEM WITH A CUTTING TORCH. ONE OF THE PIPES HE WAS CUTTING LED DOWN INTO A CEMENT TANK, WHICH WAS 16 FEET BY 8 FEET BY 6 FEET DEEP. ABOUT 21 DAYS PRIOR TO THE ACCIDENT, ANOTHER CONTRACTOR HAD APPLIED A COAL TAR EPOXY SEALER TO THE FLOOR AND WALLS OF THE TANK. THE SEALER WAS FLAMMABLE IN A LIQUID STATE. IT HAD A CURING TIME OF 14 TO 20 DAYS AT 30 TO 50 DEGREES F (LESS TIME AT A HIGHER TEMPERATURE). THE TANK WAS NOT VENTILATED AFTER THE SEALER WAS APPLIED. THE TANK WAS LOCATED BELOW A BUILDING, AND HAD ONLY A FEW SMALL OPENINGS AT THE TOP. IT CAN BE SPECULATED THAT WHEN EMPLOYEE #1 WAS CUTTING A HOLE, HOT SPARKS FELL INTO THE TANK, IGNITING THE VAPORS.