The BP report spreads blame for the explosion and the spill far and wide.
The four-month investigation has found that the accident was caused by “a complex and interlinked series of mechanical failures, human judgments, engineering design, operational implementation and team interfaces”.
The main points are indeed complex and technical, but here is Tony Hayward, BP’s outgoing chief executive, trying to make it easier to understand for those of us who don’t work on oil rigs:
To put it simply, there was a bad cement job and a failure of the shoe track barrier at the bottom of the well, which let hydrocarbons from the reservoir into the production casing. The negative pressure test was accepted when it should not have been, there were failures in well control procedures and in the blow-out preventer; and the rig’s fire and gas system did not prevent ignition.