Rig's Alarm System Disabled on Day of Blast

An electronics technician aboard the ill-fated oil rig Deepwater Horizon told an investigative panel today that an alarm system was partially shut down on the day the rig exploded. Mike Williams said the system was turned on to monitor for fire, explosive gas, and toxic gas but that its sound and light alarms had been disabled. Williams worked for rig owner Transocean Ltd.

Williams testified that he had asked before about the settings and was told the company didn't want a false alarm waking people at night. Williams said that if the system had been fully active, an alarm likely would have sounded before the explosion, which happened on the night of April 20. The rig sank 2 days later. Since then, millions of gallons of oil have poured into the Gulf. (More Gulf oil spill stories.)