On Aug. 6, 2012, a hydrocarbon release and massive fire occurred at the Chevron Refinery in Richmond, Calif. Following an investigation, the U.S. Chemical Safety and Hazard Investigation Board (CSB) released a joint report with Cal/OSHA pointing to sulfidation corrosion as the cause of the incident. CSB stressed that the petrochemical refiners carefully must examine potential corrosion mechanisms and use the safest possible construction materials to avoid experiencing this type of failure.

“The report, resulting from a cooperative effort between the CSB, Cal/OSHA, the United Steelworkers (USW) and Chevron, provides a solid, technical basis for the firm conclusion that the pipe corroded over time from sulfidation corrosion,” said CSB Chairperson Rafael Moure-Eraso.

According to CSB, 19 Chevron employees were engulfed in a vapor cloud formed by the hydrocarbon release in the incident. Eighteen workers escaped before the fire started and one employee escaped without injury after the fire ensued. The incident also resulted in six minor injuries. More than 15,000 residents in the surrounding area sought treatment at area medical facilities as a result of the release and fire.

Anamet Inc., a metallurgical laboratory in Hayward, Calif., prepared the report, which concluded that the 8-inch steel pipe, from a section designated as 4-sidecut that was installed in 1976, ruptured due to severe sulfidation corrosion. Tested pipe samples showed a very low concentration of corrosion-inhibiting silicon.

Production at the crude unit since has been suspended since the accident.

CSB: Pipe Corrosion Caused Chevron Refinery Fire
EHS Today