Transport Malta has released an investigation report into the boiler explosion on board oil/chemical tanker Torc, resulting in the death of a crewmember.
The incident took place on 8 January 2024 as the Maltese-registered ship was traveling between Agioi Theodorai and Genoa.
On 03 January 2024, Torc departed Agioi Theodoroi, Greece, after discharging part of its cargo of Paraffin. The vessel was bound for Genoa, Italy with an expected date of arrival of 10 January 2024. Shortly after departing from Agioi Theodoroi, the engineers changed over the boiler fuel consumption to very low sulphur fuel oil (VLSFO) for both boilers. However, the starboard boiler failed repeatedly to start. Eventually, both boilers were restarted on low sulphur marine gas oil (LSMGO). On the morning of 08 January 2024, the engineers, in consultation with the master and chief officer, decided to change over the fuel consumption of the boilers from LSMGO to VLSFO.
Just before 1400, the boiler fuel consumption was changed to very low sulphur fuel oil. Both boilers failed to fire because of low fuel oil temperature. Subsequently, the port boiler started working normally, but the starboard boiler failed to fire. Eventually, another attempt was made to restart it. While it was on the purge cycle, the second engineer went up to the burner platform to inspect it. At 1406, a loud explosion was heard and a fire started at the top of the starboard boiler. The fire alarm sounded within a few seconds.
The engineers went up to the boiler platform, to find the second engineer lying unconscious on top of the starboard boiler. The water mist system installed above the port boiler activated and the crew extinguished the fire with the help of portable extinguishers. The second engineer was carried outside onto the poop deck and placed in the dry provision room. The master sought medical advice from the company doctor and broadcast an emergency signal on the Digital Selective Calling system. Although the crew members attempted cardiopulmonary resuscitation, the second engineer passed away at around 1450.
Chemical analysis results made available to the safety investigation revealed that at the time of the explosion, the boiler was burning LSMGO and in the process of changing to VLSFO. The safety investigation believes that the cause of the explosion on boiler no. 1 was excessive vaporised LSMGO inside the unit and the likely presence of unburnt LSMGO inside the boiler.
Findings and other safety factors:
• The LSMGO had an elevated temperature due to the bunker fuel system preheating, in preparation for the changeover to VSLFO.
• A failure in solenoid valve caused it to remain closed, resulting in an increase in pressure within the fuel circuit.
• It was very likely that unburned LSMGO was present inside the boiler furnace.
• The failure of solenoid valve was unforeseen and unexpected by the crew members.
• The physical status of solenoid valve was not designed to be monitored and therefore provided no cues to the crew members if its imminent failure.
• The decision to start the boiler without a technical evaluation and investigation of the underlying cause for the flame failure when the VLSFO was in use can be described as an absent error identification of the boiler control system i.e., the ways in which the boiler and the burner could fail to fire as designed.
• The initial misfiring of the boiler was not perceived by the crew members to affect the boiler’s barrier systems, which were designed to either avoid an accident, or neutralise the consequences of such accident and this could have convinced the crew members to try and start the boiler, believing that the system would not collapse.
• The risk that the boiler burner would not fire, may have well been considered by the crew members, but this was not seen as a potential compromise to the vessel’s safety, given that the boiler’s barrier systems had always operated as designed.
Read the report in full: Transport Malta Marine Safety Investigation Report 01/2025
