HOUSTON (Reuters) – The U.S. Chemical Safety Board said on Wednesday that the events leading to a 2016 blast at ExxonMobil Corp’s Baton Rouge, Louisiana, refinery began when an operator disassembled a stuck valve on the alkylation unit, releasing a cloud of isobutane vapor.
Disassembling stuck valves was an “accepted practice” at the refinery, the board said in a video posted on its website on Wednesday. The vapor cloud exploded after reaching a welding unit 70 feet away that provided an ignition source.
An Exxon employee and three contractors were injured in the Nov. 22, 2016 blast and ensuing fire.
Reporting by Erwin Seba; Editing by James Dalgleish