Abstract: At approximately 1:15 p.m. on May 3, 1991, Employees #1 and #2 were working at the #2 Cat Rinoformer at the Chevron Refinery. Together with the rigging and pipe fitter/welder crew, the employees were removing a 2 in. piping that ran vertically from the steam pump to an 18 in. line that had already been cut off. Employee #1 was using a cutting torch on the bolts of the flange, while Employee #2 was standing on the scaffold platform above the steam pump. When Employee #1 cut the second or third bolt, liquid material came out the flange, followed by a large flash fire. Employee #1 ran to escape the fire but sustained first- and second-degree burns. Employee #2 ran down the scaffold ladder and jumped, breaking his right lower leg.