Abstract: THREE EMPLOYEES WERE INSTALLING A FITTING TO CONNECT A NEW SECTION TO THE MAIN GAS LINE NEAR A PROPANE PLANT. THEY COMPLETED THE CONNECTION AND BEGAN SOAPING OUT THE FITTING, CHECKING FOR LEAKS. ONE MAN WAS IN THE EXCAVATION DOING THE SOAPING WHILE THE OTHER TWO WERE STANDING AT THE EDGE OF THE EXCAVATION WATCHING AND MAINTAINING RADIO CONTACT WITH A CREW AT THE PROPANE PLANT. THE PLANT WAS LOCATED ABOUT 300 FEET AWAY. THE LINE WAS CHECKED AT 100 PSI AND NO LEAKS DETECTED. THE LINE WAS CHECKED AGAIN AT 300 PSI. AT THAT POINT THE FITTING BLEW OFF THE OLD SECTION OF PIPE. THE FORCE OF THE ESCAPING GAS KILLED EMPLOYEE #1, WHILE THE 2 EMPLOYEES STANDING AT THE EXCAVATION EDGE RECEIVED ONLY MINOR INJURIES NOT REQUIRING HOSPITALIZATION.