NTSB prepares to finalise report on Conception dive boat fire

Due to the risk of COVID-19 transmission, the first hearing into one of the most serious marine casualties in the U.S. in recent memory will be held via teleconference. The National Transportation Safety Board has scheduled its first public session on the loss of the dive boat Conception for the morning of October 20, The NTSB’s five-member board will vote on the findings, probable cause and recommendations in a draft of the board’s not-yet-released final report.

The dive boat Conception burned and sank in the early hours of September 2, 2019 off Santa Cruz Island, California. 34 people lost their lives in the accident, putting it among the ranks of the deadliest civilian marine casualties in recent U.S. history.

The cause of the casualty has not yet been definitively established, but an electrical fire or battery charging fire is one suspected cause. The dive boat operator offered passengers access to 120-volt power strips for the purpose of recharging high-capacity batteries for camera gear, underwater scooters and other equipment. It is suspected that the load on the circuit may have exceeded the electrical system’s design limits or that one of the batteries may have overheated and caught fire. The U.S. Coast Guard has issued a preliminary warning to passenger boat operators to consider limiting battery charging and excessive use of power strips.

The design of the Conception has also come under scrutiny: her lower berthing area, where all victims were located prior to the fire, had one relatively small emergency escape hatch located above the top level of a bunk bed. In addition, her hull was built with fiberglass-epoxy composite over a plywood core, a combination that proved to be flammable once ignited. The vessel burned to the waterline and sank within hours of the start of the fire. The U.S. Coast Guard has said that Conception passed all inspections prior to the accident.

In addition, according to testimony from three of the five surviving crewmembers, all personnel on board were asleep at the time the fire broke out. NTSB has suggested that based upon available evidence, it appears likely that there was no roving watchstander while the vessel lay at anchor.

The accident was severe enough to merit three separate lines of inquiry: a federal criminal investigation led by the Coast Guard Investigative Service, an NTSB safety investigation and a U.S. Coast Guard Marine Board of Investigation (MBI), a formal process reserved for the most serious casualties. The NTSB will be the first to offer published conclusions.

The hearing would ordinarily be a well-attended event, but in the era of COVID-19, social distancing standards require that it be held virtually. The meeting will be webcast to the public, with the members of the board and NTSB’s staff attending remotely. There will be no in-person elements to the discussion and vote.

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