​On March 24, 2023, about 2252 eastern daylight time, a fire broke out in the deck 1 wait station on the passenger vessel Spirit of Boston while it was moored at the Commonwealth Pier in Boston Harbor, Boston, Massachusetts. All 16 persons aboard evacuated the vessel to the pier. The local fire department responded and extinguished the fire. There were no injuries, and no pollution was reported. Damage to the vessel was estimated at $3.1 million.

​We found that the fire originated in the deck 1 wait station under a plastic glassware rolling cart and was caused by an improperly extinguished chafing fuel heating canister that was unintentionally dropped in the area. Without a marine crewmember on board, City Cruises US’s (the vessel’s operator) emergency response plan for a fire aboard the Spirit of Boston was unable to be executed as intended. Had a marine crewmember been on board at the time, they likely could have extinguished the fire before it grew and spread. 

We found that City Cruises US’s lack of documented procedures on how to handle open-flame devices, like chafing fuel heating canisters, on board its vessels increased the risk of a fire. A safety management system (SMS) would have established mechanisms for the company to identify unsafe practices and fire risks on the Spirit of Boston and take corrective action before the fire occurred. Further, we found that requiring SMSs on all US-flagged passenger vessels would enhance operators’ ability to identify and mitigate safety risks by establishing mechanisms to identify unsafe practices and take corrective action before an accident occurs.

We determined the probable cause of the fire aboard the passenger vessel Spirit of Boston was the improper extinguishing and disposal of a chafing fuel heating canister due to City Cruises US’s lack of documented procedures for handling open-flame devices, which led to the ignition of a plastic glassware rolling rack. Contributing to the growth and spread of the fire was City Cruises US not requiring a marine crewmember—designated and trained to execute City Cruises US’s emergency response plan for a fire aboard a vessel—to remain aboard the vessel until all hospitality staff and other noncrew personnel departed the vessel.

​As a result of this investigation, the NTSB issued four new recommendations and reiterated one recommendation. ​​

We recommended that City Cruises US require at least one marine crewmember—who is properly trained to respond to shipboard emergencies, including fire—to remain on board its vessels until all hospitality staff and other noncrew personnel depart the vessel. We also recommended that City Cruises US develop procedures for, and train crewmembers and hospitality staff on, the proper handling and extinguishing of chafing fuel heating canisters on board its vessels.

We further recommended that City Cruises US implement an SMS for its fleet to improve safety practices and minimize risk. We also reiterated Safety Recommendation M 12 3 to the US Coast Guard to require all operators of US-flag passenger vessels to implement SMSs, taking into account the characteristics, methods of operation, and nature of service of these vessels, and, with respect to ferries, the sizes of the ferry systems within which the vessels operate.

Finally, we recommended that the Passenger Vessel Association share with its members the circumstances of this accident, including the importance of having at least one marine crewmember on board a vessel with hospitality staff or noncrew personnel, having procedures for handling open-flame devices, and implementing SMSs.