A boiler maker, 36, suffered fatal burns after an explosion occurred at a refinery. A contractor employed the victim and two injured co-workers at the facility. The three employees were hospitalized as a result of the explosion. The victim died four days later from burns over approximately 90% of his body. The events occurred in the area of the South Flare and Knock-Out Drum (KO Drum). A 36-inch pipe delivers hydrocarbons from the refinery production area and collects them in the KO Drum. Another 36-inch pipe exits the top of the KO Drum and delivers vapors to be burned at the South Flare to relieve pressure from the production area. The process leading up to the fatality began when, during a turnaround (shut down for maintenance), an environmental project was begun to capture flare gas and re-use it as fuel or feedstock rather than burn the gas in the flare. The 36-inch pipe between the KO Drum and the South Flare would be altered by installing a bypass allowing the South Flare to remain in service while work was performed at the KO Drum and the Flare Gas Recovery System.
To begin the recovery project, the KO Drum and Flare Gas Recovery System had to be isolated from the South Flare and piping to the flare. Three contractor employees climbed onto the catwalk above the South Flare KO Drum at the 36-inch diameter outlet pipe. Their job was to open the pipe flange, insert a pipe blind, and close the flange.