BP's Toledo Refinery Hit by Multiple Problems, Leak Before Fire, Agency Finds

BP's Toledo, Ohio, oil refinery experienced multiple problems and a naphtha spill before a fire that killed two workers last year, according to a report by the U.S. Chemical Safety and Hazard Investigation Board (CSB). The two refinery workers died from their burns following an explosion in September 2022 at the 150,800 barrel-per-day Toledo oil refinery.

The report said that at 3:20 a.m. on Sept. 20, an emergency pressure-relief valve on the feed to the naphtha hydrotreater (NHT) opened. The same valve opened at 8 a.m. as well, while another relief valve upstream on the NHT feed opened around the same time and began vibrating.

The refinery's emergency response team isolated a 63,625-pound naphtha leak that occurred due to the piping vibration. The Crude 1 Unit and all other units except the NHT and the saturated gas plant continued to operate, while the coker gas plant (CGP) was bypassed as a repair plan was being evaluated, the report said.

"At approximately 6:09 p.m., flammable liquid naphtha began to fill a Fuel Gas Mix Drum. ... Starting at approximately 6:32 p.m., naphtha from the Mix Drum was also drained directly to the ground creating a vapor cloud," the report said.

"At approximately 6:46 p.m., the vapor cloud of flammable naphtha that had formed on the ground reached an ignition source, which generated a large fire."

BP said in a statement that it had been cooperating with CSB as it investigates the incident further.

A report published by U.S. investigators in March showed the company violated process safety rules and did not properly train workers at the Toledo refinery.

(Reporting by Ashitha Shivaprasad, Brijesh Patel and Harshit Verma; Additional reporting by Rahul Paswan; Editing by Louise Heavens, Leslie Adler and Jamie Freed)