Tesoro refinery explosion was preventable, CSB says

Seattle – The fatal explosion at the Tesoro Corp. refinery in Anacortes, WA, in 2010 could have been prevented if the company had replaced steel tubing with inherently safer alloys, according to a new report from the Chemical Safety Board.

Seven workers died in the explosion, which CSB said was caused by a “high temperature hydrogen attack” that cracked and weakened carbon steel tubing over time until it ultimately burst.

The draft report, released along with a computer animation in January, said the inherently safer materials that Tesoro should have used were well known within the industry, but not mandatory.

Another problem CSB identified was a poor safety culture in which employees had become complacent about recurring flammable leaks and fires.

CSB noted that the Tesoro incident was similar to the 2012 fire at a Chevron refinery in Richmond, CA, that CSB concluded resulted from the company’s failure to upgrade corroded equipment and apply inherently safer technology. The board’s recommendations include a national mandate at the state and federal level requiring chemical facilities to use inherently safer technology when possible.

Public comments on the draft report are due March 16.