AMSA issues recommendations from NTSB probe into fatal 2019 dive boat fire off California

The passenger vessel Conception at sunrise prior to sinking, September 2, 2019. (Photo: Ventura County Fire Department)

The Australian Maritime Safety Authority (AMSA) has issued Domestic Commercial Vessel Safety Alert 1/2021, which the agency says is intended to raise awareness of recommendations made by the US National Transportation Safety Board (NTSB) following the investigation into the fire and subsequent loss of the passenger vessel Conception.

AMSA claims that, while this incident did not occur in Australia, the findings of the NTSB investigation provide the Australian maritime industry with an opportunity to learn from the unfortunate experience of others.

The incident

Conception was a 22.8-metre, US-flagged passenger vessel that caught fire in the early hours (local time) of September 2, 2019. Of the 39 people on board, 34 perished in the incident.

When the fire broke out, the vessel was at anchor off Santa Cruz Island, California.

Five crewmembers were asleep in the crew berthing area on the upper deck. One crewmember and all 33 passengers were asleep in the bunkroom below.

A crewmember sleeping in an upper deck berth was awakened by a noise and got up to investigate. Upon seeing a glow outside, he realised that fire was rising up from the saloon compartment directly below, and he immediately alerted the other four crewmembers sleeping on the upper deck.

The master was able to send a distress message to the US Coast Guard.

The crewmembers attempted to access the saloon to assist the passengers and the other crewmember in the bunkroom below the main deck, but access was blocked by fire and thick smoke.

The coast guard and other first responder vessels began arriving on scene within 90 minutes. However, despite firefighting and search and rescue efforts, the vessel burned to the waterline and sank just after daybreak.


The NTSB report drew 18 conclusions, the following of which are considered worthy of note by those persons involved in operating passenger vessels in Australia:

  • Although a definitive ignition source cannot be determined, the most likely ignition sources include the electrical distribution system of the vessel, unattended batteries being charged, improperly discarded smoking materials, or another undetermined ignition source.
  • Although the arrangement of detectors aboard Conception met regulatory requirements, the lack of smoke detectors in the saloon delayed detection and allowed for the growth of the fire, precluded firefighting and evacuation efforts, and directly led to the high number of fatalities in the accident.
  • The absence of the required roving patrol on Conception delayed detection and allowed for the growth of the fire, precluded firefighting and evacuation efforts, and directly led to the high number of fatalities in the accident.
  • Conception’s bunkroom emergency escape arrangements were inadequate because both means of escape led to the same space, which was obstructed by a well-developed fire.
  • Although designed in accordance with the applicable regulations, the effectiveness of Conception’s bunkroom escape hatch as a means of escape was diminished by the location of bunks immediately under the hatch.
  • Conception’s operator provided ineffective oversight of its vessels’ operations, which jeopardised the safety of crewmembers and passengers.
  • Had a safety management system been implemented, the operator could have identified unsafe practices and fire risks on Conception and taken corrective action before the accident occurred.
  • Implementing safety management systems on all domestic passenger vessels would further enhance operators’ ability to achieve a higher standard of safety.

While the NTSB investigation did not determine the cause of the fire, the analysis section of the report included the following text which is worth noting:

“Since the salon compartment was a critical element in the egress pathway from the passenger bunkroom, prudent fire safety planning would suggest that risky activities (unattended charging of batteries) and materials, such as the plastic chairs and polyethylene trash cans that could contribute to a fire should have been minimised in this area. This was not the case on Conception.

“Crew statements, as well as statements from previous passengers, indicated that the overnight, unattended charging of a large number of batteries was a normal practice in the salon compartment and was a risk that had not been considered. Each device and battery represented a separate potential source of ignition.

“The passengers on Conception were recreational divers, so in addition to common types of electronic items – such as phones, tablets, digital cameras, and laptops – divers also used underwater cameras, flashes, strobes, and flashlights.”

AMSA will consider the NTSB report in full when reviewing the current regulatory requirements for domestic commercial vessels, including the standards for fire safety and accommodation and arrangement.


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