Abstract: Employee #1 was preparing to replace a gas line on a small compressor for a walk-in freezer. The compressor was located within a fenced area that was small and confined. Employee #1 was using acetylene and oxygen cylinders, 10 and 20 cubic feet respectively, a Uniweld torch, type 170, a Uniweld acetylene regulator, MC-18R, and a Uniweld oxygen regulator, RU. Apparently, the compressor vibrated excessively, causing the gas line to separate from its connection. There was a backfire that caused a flashback or flareback to the acetylene regulator. Employee #1 was burned over 40 percent of his body. He died of complications three weeks later. There were no witnesses to the accident.