BP's oil spill probe criticised
US engineering experts probing the Gulf of Mexico oil spill exposed holes in BP's internal investigation as the company was questioned for the first time in public about its findings.
BP's head investigator acknowledged that the company's probe had limitations.
Mark Bly, head of safety and operations for BP, told a National Academy of Engineering committee that a lack of physical evidence and interviews with employees from other companies limited BP's study.
The internal team only looked at the immediate cause of the April disaster, which killed 11 workers and unleashed 206 million gallons (780 million litres) of oil into the Gulf.
"It is clear that you could go further into the analysis," said Bly, who said the investigation was geared to discovering things that BP could address in the short term. "This does not represent a complete penetration into potentially deeper issues."
For example, the National Academy of Engineering panel noted that the study avoided organisational flaws which could have contributed to the blast. BP has focused much of its work on decisions made on the rig, not with the managers on shore.
Najmedin Meshtaki, a professor at the Viterbi School of Engineering at the University of Southern California, said he wondered why BP named its report an accident investigation when it left critical elements out. He asked BP to turn over information on shift duration and worker fatigue.
"How could you call this great work accident investigation ... and not addressing human performance issues and organisational issues and decision-making issues?" Prof Meshtaki asked.
He referred specifically to the confusion that occurred leading up to the explosion, when many on board the rig were busy with work associated with finishing up a well. This distraction could have led to missed signs that something was wrong. "It wasn't intended to be anything that it isn't," Bly responded. "It was a good contribution and a good foundation for further work for BP itself and others."
BP's study found eight separate failures led to the oil rig accident. The report blamed the oil giant and other companies.