CSB approves ‘landmark’ Tesoro report

Anacortes, WA – The Chemical Safety Board on May 1 approved what board chair Rafael Moure-Eraso called a “landmark” report on an April 2010 explosion at the Tesoro refinery in Washington state.

Seven workers died in the tragedy. CSB determined the cause of the blast was a long-term, undetected, high-temperature hydrogen attack of the steel equipment, which led to a vessel rupture and massive release of flammable hydrogen and naphtha.

This conclusion is the same as the one CSB made when it released its draft report Jan. 30. CSB accepted public comment on the draft, and made changes to the final report as a result.

“These findings – and similar ones we have made in other refinery investigations – have led us to recommend sweeping changes to the regulatory system,” Moure-Eraso said in a statement on the report.

Recommendations include improving how refineries are regulated on the federal and state level, such as the Environmental Protection Agency requiring inherently safer systems analysis and the hierarchy of controls, and the Washington legislature enhancing its process safety management regulatory framework.