Fire Highlighted Confusion About CO2 System
The Danish Marine Accident Investigation Board has released a summary report on the fire on board the crew transfer vessel World Calima citing problems that may arise when using a CO2 system in an emergency because the operation of the system cannot be trained in practice in periodic fire drills.
On November 15, 2017, World Calima left Helgoland with a crew of five and 11 technicians who were to disembark at three different windfarm installations. When the master reversed the engine to get away from one of the wind turbines, he observed a fire in the engine room on the CCTV. The alarm was raised, and the remaining eight technicians on board assembled on the foredeck and donned immersion suits. The technicians were quickly evacuated to a nearby rescue vessel from the German coastguard in case the fire spread.
The master released the vessel’s CO2 system from the bridge and began to cool the external accommodation bulkheads from the outside using water from the vessel’s fire hoses. When he had activated the remote control lever for the CO2 installation, he could neither see nor hear whether the system had been released. Therefore, the mate went down to the CO2 room on the aft of the vessel and activated it manually by pulling a wire directly connected to the valves on the bottles.
Because the engine room was filled with smoke, the crew could not monitor the development of the fire using the cameras. Rather, they had to touch the bulkhead to check whether the temperature was decreasing. After a while, they ascertained that the fire had been extinguished, and World Calima was towed back to Helgoland by the German coastguard.
The investigation identified that the origin of the fire was below a worktable in the engine room – either on a shelf or on the floor below the table. The source of ignition could not be identified, because the area had burnt out. Once it had ignited, the fire had spread to the rest of the table, and the heat from the fire spread on the upper deck in the engine room and caused damage to light fixtures, cabinets and cables.
The investigators stated that ships constructed of aluminum are especially vulnerable to fire because the ship’s structure is quickly eroded by the effect of heat, and minor fires may quickly develop into an uncontrollable emergency. Therefore, it was decisive that an early decision was made to evacuate the technicians and the crew, even though this decision may expose the technicians to danger when they are leaving the vessel by means of ladders or jumping into a liferaft.
In this accident, the technicians were prepared to act fast. They could easily don the immersion suits and be evacuated quickly to another ship in the vicinity. This was the case because they were not considered ordinary untrained passengers, but had instead acquired detailed knowledge about the onboard emergency procedures, which turned out to be effective. Because of this, the crew could quickly focus their resources on fighting the fire.
The remote-releasing of the CO2 installation on board was impeded by the fact that it had not been possible to train the practical aspects of its use. Therefore, the training was based on ideas about how the system would function in a real emergency. Furthermore, it was feared that the system would be activated unintentionally.
When the system is operated in stressing circumstances, the risk of incorrect operation will increase, and the consequences may be serious, because time is of the utmost importance in connection with fires, especially on board rather small aluminum vessels. In this fire, it was expected that it would be evident whether the system had been activated. Since it was not clear whether the system had been activated, it was necessary to open the door to the CO2 room and to release the system locally. Doing this without being equipped with a fresh air breathing apparatus is, however, connected with a considerable risk because a suddenly arising leakage may have fatal consequences.
Therefore, the CO2 system must not only be accompanied by an intuitive manual, but also be accompanied by information stating what is expected to happen upon activation. Furthermore, the fire fighting strategy must contain information about the actions to be made following use of the system.