Abstract: At 11:50 p.m. on December 21, 2004, Employee #1, working for Timec Co Inc. in Torrance, CA, was part of personnel performing a heat treatment process of frozen pipelines that contained heavy oil residue at a petroleum refinery plant. The heavy oil residue had frozen because of low temperature and unheated pipelines; the treatment was performed by applying external heat pads that attached to segments of the pipes. Employee #1 was responsible for keeping combustible materials and unauthorized personnel out of the area where the pipelines were being heated. At the time of the incident, Employee #1 was located underneath a section of pipe that was being heated, which was placed in a pipe rack 13 ft above ground. The heated pipe above him failed, splitting open and releasing a fire ball that caused first and second-degree burns to his face and right hand and first, second- and third-degree burns to his left hand. Employee #1 was hospitalized for 2.5 days. After the accident, a review of the temperature chart on the electric heating console revealed that the area where the pipeline failed had risen in temperature to 980 degrees F over about a 45 minute period before the line burst open. The thawing procedure was not written, but interviews indicated that the set point was supposed to be 400 degrees F. The heating of the solidified pipelines had begun 2 days before. Thirty-six hours prior to the accident, on day shift, another pipeline had failed while being externally heated, but no fire had occurred. Investigations as to why the temperature rise was undetected by the control operator and or the thermocouple gages installed were inconclusive.