Abstract: EMPLOYEE #1 WAS USNG A PROPANE TORCH TO HEAT THE BACK PLATE, TAKE-OUT PIPE AND TRANSFER LINE OF A 5,000 GALLON ASPHALT DELIVERY TANK. THE ASPHALT WAS BEING TRANSFERRED TO A 20,000 GALLON HIGHWAY TANK. THE 5,000 GALLON TANK BECAME A PRESSURE VESSEL WHEN IT'S TWO 3 INCH AIR VENT PIPES WERE CAPPED, THE 20 INCH MANHOLE COVER WAS BOLTED TO THE TANK RIM AND APPROXIMATELY 75 PSI OF COMPRESSED AIR WAS PUMPED INTO THE TANK THROUGH A ONE INCH AIR HOSE CONNECTED TO A ONE INCH INLET PIPE ON TOP OF THE TANK. THE BACK PLATE BLEW OUT. THE BLAST KNOCKED EMPLOYEE #1 TO THE GROUND AND INJURED HIS KNEE. HE ALSO SUFFERED FIRST DEGREE BURNS ON HIS RIGHT HAND, WHICH CAME IN CONTACT WITH THE HOT ASPHALT. HIS FACE RECEIVED MULIPLE SUPERFICAL ABRASIONS FROM ASPHALT PARTICLES, AND HIS UPPER LEGS WERE BRUISED. HE WAS TREATED AND RELEASED AT THE HOSPITAL.