BP focused too much on the little details of personal worker safety instead of the big systemic hazards that led to the 2010 Gulf of Mexico oil spill and was not as strict on overall safety when drilling rigs involved other companies that they hired, a US government safety panel has concluded.
Eleven workers were killed in the April 2010 explosion of the Deepwater Horizon rig and about 200 million gallons (757 million litres) of oil flowed into the gulf from the blown-out Macondo well.
The company had the lease on the well, but the drilling rig was owned and operated by another company and BP has faulted drilling contractor Transocean.
That contractor-owner split made a difference in major accident prevention with the oil disaster, the US Chemical Safety Board concluded in a presentation to be made at a hearing in Houston.
"BP applied lesser process safety standards" to rigs contracted out than it does to its own facilities, safety board managing director Daniel Horowitz told The Associated Press. "In reality, both Transocean and BP dropped the ball on major accident hazards in this case."
The oil company "did not conduct an effective comprehensive hazard evaluation of the major accident risks for the activities of the Deepwater Horizon rig or for the Macondo well" because BP's large risk evaluation programme "looked only at BP assets, not drilling rigs that it contracted" to other firms for operation, investigators said.
A BP spokesman said the company "stepped up" and developed more rigorous safety indicators following the accident.
The safety board said when BP looked at offshore endeavours it "focused on financial risks, not process safety risks". And after the Deepwater Horizon explosion, the company's own accident investigation report "recommended requiring hazard reviews of BP-owned and contracted rigs", the safety board's presentation says.
"That's very disturbing because the Gulf of Mexico belongs to the American people," said former senator Bob Graham of Florida, who co-chaired a different government oil spill investigation, one appointed by President Barack Obama.
The Chemical Safety Board's findings, which mostly mirror the report from Mr Graham's panel and another, pointed at a second standard for what BP owned and operated and what it did not. Mr Graham said he did not know that.