A fire that severely burned four workers at the ExxonMobil refinery in Baton Rouge, La., occurred when operators inadvertently removed bolts that secured a piece of pressure-containing equipment to a plug valve. The uncontained valve came apart and released flammable hydrocarbons, forming a vapor cloud that quickly ignited and injured the workers. The explosion occurred on November 22, 2016.
Had a “hierarchy of controls” — a method of evaluating safeguards to provide effective risk reduction — been applied, the risks could have been mitigated, according to the final report and safety bulletin from the U.S. Chemical Safety Board (CSB). The CSB released a safety video describing the incident and ways to mitigate the risks that led to the explosion. (View the full video on the CSB's YouTube Channel.)