Key rig alarm disabled before blast: rig worker

HOUSTON (Reuters) – An emergency alarm that could have warned workers aboard the doomed Deepwater Horizon Gulf of Mexico drilling rig was intentionally disabled, a rig engineer told US investigators on Friday.

Mike Williams, chief engineer technician aboard Swiss-based Transocean Ltd’s rig, said the general alarm that could have detected the cloud of flammable methane gas that enveloped the rig’s deck on April 20 was “inhibited”.

“They (rig managers) did not want people woke up at three o’clock in the morning from false alarms,” Williams told a six-member federal board in the New Orleans suburb of Kenner, Louisiana.

Williams’ appearance capped a week of testimony from company officials involved in the rig, which exploded on April 20 and sank two days later, killing 11 crewmen and sparking the worst oil spill in US history.

The Transocean-owned rig was drilling a well a mile beneath the Gulf under contract for London-based BP Plc.

However, written statements from several rig personnel taken by US investigators and obtained by Reuters refer to alarms sounding on the rig.

“At time of incident, I was in engine control room working on nightly log,” wrote Douglas Brown, the rig’s chief mechanic. “At which (sic) multiple gas alarms went off.”

“The general alarm configuration on the Deepwater Horizon was intentional and conforms to accepted maritime practices,” Transocean said in a statement. The rig “had hundreds of individual fire and gas alarms, all of which were tested, in good condition, not bypassed and monitored from the bridge.”

Four Transocean witnesses declined to appear voluntarily on Wednesday at the hearings before a joint US panel convened by the US Coast Guard and the Interior Department’s Bureau of Ocean Energy Management, Regulation, and Enforcement.

The board on Thursday declared two BP officials “parties of interest” in the investigation, after they declined to appear.