Why would Napolitano assume blowout preventers never fail? The evidence is overwhelming that they do fail.
http://www.politico.com/news/stories/0510/37373.html<edit>
And she said nobody would have predicted that a blowout preventer wouldn’t work.
“I think before the blowout, it is clear that there was an assumption that a <blowout preventer> would never fail,” Napolitano said.
http://www.dailyfinance.com/article/ap-investigation-blowout-preventers/1051475/<edit>
HOUSTON -Cutoff valves like the one that failed to stop the Gulf of Mexico oil disaster have repeatedly broken down at other wells in the years since federal regulators weakened testing requirements, according to an Associated Press investigation.
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But a detailed AP review shows that reliability questions have long shadowed blowout preventers:
— Accident reports from the U.S. Minerals Management Service, a branch of the Interior Department, show that the devices have failed or otherwise played a role in at least 14 accidents, mostly since 2005.
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"There is a history of failure with the blowout prevents that obviously was not heeded," he said.
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In 1999, right after that rule change, an MMS-commissioned report by a research group identified 117 blowout preventer failures at deepwater rigs within the previous year. These breakdowns created 3,638 hours of lost time — a 4 percent chunk of drilling time.
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