1
The blowout preventer at the BP well failed, leading to the spill.
2
The Deepwater Horizon's blowout preventer failed to operate and seal the well.
3
April 25 - Efforts to activate the well's blowout preventer fail.
4
That pushes blowout preventer removal to Friday or Saturday, he said.
5
A blowout preventer, intended to prevent release of crude oil, failed to activate.