The Navy has directed all public shipyards to empty industrial shop vacuum cleaners after each shift because combustibles inside a cleaner at the Portsmouth Naval Shipyard in Kittery started a fire that caused $400 million worth of damage to a nuclear submarine.

The Navy said there was no defect in the vacuum cleaner and it was unplugged when the fire broke out in a forward compartment of the USS Miami on May 23. The fire burned for 10 hours before it was put out by firefighters from three states.

The Navy is investigating the cause of the fire and corrective steps it should take. Conclusions and recommendations are expected in two weeks.

The Navy took the immediate step of warning all shipyards that vacuum cleaners should be emptied or removed from vessels at the end of each shift, according to a release issued Friday.

The release does not say whether the Navy has identified what was vacuumed into the cleaner’s container and ignited the fire.

Repairs to the nuclear submarine would cost $400 million, plus $40 million in disrupted work schedules and private contractor costs in Kittery and other shipyards. The Navy is still assessing whether the steel hull of the sub was damaged too much by the fire to be repaired. It won’t know that until later this month.

The Navy is operating under the assumption that the submarine will be repaired, and is developing a schedule for when the USS Miami would be returned to service.

Staff Writer David Hench can be contacted at 791-6327 or at:

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