Investigation finds BP at fault for fatal US refinery explosion that killed two
17 March 2023
A federal investigation into two workers' fatal burns at an Oregon, Ohio, refinery's crude unit has found its operator, BP Products North America Inc. violated the US Department of Labor's process safety procedures for highly hazardous materials and failed to adequately train the workers.
Image: CSB
As the workers attempted to correct rising liquid levels in the fuel gas mix drum, a flammable vapour cloud formed, ignited and then triggered an explosion in September 2022, causing the deadly burns.
Inspectors with the department's Occupational Safety and Health Administration identified the training deficiencies and failure by BP Products North America to meet OSHA's process safety management procedures. They also determined naphtha – a flammable liquid hydrocarbon mixture – was released when flow control valves were opened in an attempt to regulate an overfill occurring in upstream process equipment. The opened valve allowed the flammable liquid to enter the refinery's fuel gas system.
OSHA cited BP Products for failing to implement shutdown procedures for the equipment when requested by the operators responding to the naphtha release and for not clearly defining conditions for emergency shutdown of the crude tower.
"Federal safety standards require BP Products North America Inc. to develop companywide process safety and response procedures that address worst-case scenarios," explained OSHA Area Director Todd Jensen in Toledo, Ohio. "This tragedy is a reminder of why employers must consistently reevaluate those procedures for accuracy and ensure workers are properly trained to respond in dangerous situations."
OSHA proposed $156,250 in penalties, an amount set by federal statutes, and cited the company for 10 serious violations, and one other-than-serious violation of process safety management procedures. Specifically, the agency found BP Products failed to:
- Train operators to identify the presence of naphtha during an upset condition.
- Develop and implement safe work practices for responding to upset conditions.
- Document design for pressure safety valves, including for an overpressure scenario.
- Address hazards of overfilling process vessels, and safeguards needed to protect against an overfill.
- Evaluate for engineering or administrative controls for draining process equipment during upset conditions.
- Address human factors with the operation of the inside control board screen loading delays.
- Ensure process hazard assessments were accurate with respect to level indicator safeguards.
The US Chemical Safety and Hazard Investigation Board (CSB) is still working on an ongoing investigation into the incident. In its last investigation update in November 2022, the CSB said it is examining the valves and interconnected piping associated with the refinery’s Fuel Gas Mix Drum located in the Crude 1 Unit.
The Fuel Gas Mix Drum was installed around 2016 and combines various sources of flammable gases for use as fuel in refinery furnaces and boilers, the CSB said. The Fuel Gas Mix Drum is primarily a vapour-filled vessel and is equipped with features to remove liquids that could be entrained with vapor or that otherwise enter the refinery’s fuel gas system.
CSB investigators are focusing on a release of flammable naphtha from the Fuel Gas Mix Drum. The investigation team is conducting witness and employee interviews, documenting the incident scene, collecting equipment and equipment components, obtaining documents, and evaluating recorded process data. The CSB will continue providing updates as the investigation progresses and additional information becomes available.
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