LOS ANGELES, Sept. 12 (Xinhua) -- The U.S. National Transportation Safety Board (NTSB) has released a preliminary report Thursday on the dive boat fire which killed 34 people off the California coast, confirming that all crew members were asleep when the boat caught fire.
According to Coast Guard regulations, boats like the Conception, are required to have a crew member on lookout duty throughout the night.
According to the two-page report released by the NTSB, five crew members were asleep in berths behind the wheelhouse on the second deck, and another one was asleep in the bunkroom below deck when the boat caught fire around 3 a.m. on Sept. 2 and sank.
The U.S. Department of Justice confirmed that it was participating in the joint investigation with the U.S. Coast Guard, the Federal Bureau of Investigation, the Bureau of Alcohol, Tobacco, Firearms and Explosives, and the Santa Barbara County Sheriff's Office.
Investigators will be looking at key issues, including whether passengers had been informed of safety procedures on board. They will also be looking carefully at an escape hatch which can provide an alternative route out of the sleeping area.
NTSB spokesman Eric Weiss said investigators are looking at "all ignition sources" as they try to find the source of the blaze on the boat.
The NTSB will include the findings of its investigation in a final report, which may take more than a year to complete, Weiss said.
The U.S. Coast Guard records show the Conception passed its two most recent inspections with no safety violations.
Divers on Wednesday recovered the body of the final missing victim of the boat fire.
The 34 victims - 21 women and 13 men - ranged from 16 to 62 years old, according to authorities.
Preliminary examinations indicate the victims died of smoke inhalation and perished before they were burned, according to Santa Barbara County Sheriff Bill Brown.
In the wake of the fatal boat fire, the U.S. Coast Guard issued new safety requirements to passenger vessels on Wednesday to limit the unsupervised charging of lithium-ion batteries and the use of power strips and extension cords.
The bulletin also suggests that owners and operators of vessels review emergency duties with the crew, identify emergency escapes, check all firefighting and lifesaving equipment on board, and look at the condition of passenger accommodation spaces for "unsafe practices or other hazardous arrangements."
A total of 39 people were on board the 75-foot dive boat when the fire broke out. The 34 victims were thought to be sleeping below deck when the boat was engulfed by fire. Five crew members on deck survived by jumping into the water, and were later rescued.