A rig worker on Friday told a government panel that the emergency alarm on the Deepwater Horizon was not fully activated the day the oil rig caught fire and exploded, killing 11 people and setting off the massive spill in the Gulf of Mexico.

The general safety alarm was habitually set to “inhibited” to avoid waking up the crew with late-night sirens and emergency lights, said Mike Williams, the rig’s chief electronics technician.

Williams told the federal panel of investigators, “They did not want people woke up at 3 a.m. from false alarms.” Consequently, the alarm did not sound during the emergency, leaving workers to relay information through the loudspeaker system.

He added that while it is not known whether it would have saved the workers who died in the April 20 disaster, the lack of a fully functioning alarm hampered the effort to safely evacuate the rig.

Workers were allowed to set the alarm to prevent it “from sounding unnecessarily when one of the hundreds of local alarms activates for what could be a minor issue or a non-emergency,” said Transocean, which leased the rig to BP, in a statement.

(Thanks to The New York Times and Wikipedia)