Abstract: EMPLOYEE #2 WAS ASSIGNED THE JOB OF FILLING A 126 POUND LP-GAS TANK LOCATED UNDER A TRAILER THAT PROVIDES FUEL FOR THE REFRIGERATION UNIT (TRAILER 103J, 1970 GREAT DANE, COLDMOBILE REFRIGERATION UNIT). NORMAL PROCEDURES WERE FOLLOWED TO CONNECT THE HOSE AND FILL THE TANK. WHEN THE TANK WAS FILLED AND THE PUMP TURNED OFF IT WAS DISCOVERED THAT THE TANK VALVE HAD NOT SEATED PROPERLY AND WAS OBVIOUSLY LEAKING. THE PUMP WAS TURNED ON AND OFF AGAIN IN AN UNSUCCESSFUL ATTEMPT TO RESEAT THE VALVE. EMPLOYEE #2 THEN TAPPED ON THE VALVE WITH HIS HAND, THEN CALLED EMPLOYEE #1 FOR ASSISTANCE. GAS HAD BEEN LEAKING FOR ABOUT FIVE MINUTES BY THIS TIME. WHILE THE TWO EMPLOYEES WERE DISCUSSING THE PROBLEM, THE LP VAPORS WERE IGNITED BY AN UNKNOWN SOURCE. A FLASH FIRE RESULTED, CAUSING SECOND AND THIRD DEGREE BURNS TO BOTH EMPLOYEES, WHO RAN FROM THE AREA AS SOON AS THE FIRE BEGAN. BOTH WERE HOSPITALIZED.