Fire on board revealed CO2 system confusion

A summary report from the Danish Marine Accident Investigation Board on a fire on board crew transfer vessel World Calima has cited problems that might occur when using a CO2 system in an emergency, mainly because the operation of the system cannot be trained in practice in standard fire drills.

World Calima left Helgoland with a crew of five and 11 technicians on November 15th. The technicians were scheduled to disembark at three windfarm installations. When the master reversed away from one of the wind turbines, CCTV revealed a fire in the engine room. An alarm was raised and the remaining eight technicians on board assembled on the foredeck and donned immersion suits. They were evacuated promptly to a nearby German coastguard rescue vessel.

The master then released the vessel’s CO2 system from the bridge and began to cool the external accommodation bulkheads from the outside with water from the vessel’s fire hoses. However, when he activated the remote control lever for the CO2 installation, he could neither see nor hear whether the system had been released. 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 with cameras. Instead 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, although the source of ignition could not be identified because the area had burned out. 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, causing damage to light fixtures, cabinets and cables.

The investigators said that ships constructed of aluminium were vulnerable to fire because the ship’s structure was eroded rapidly by the effect of heat. As a result, minor fires could develop rapidly into an uncontrollable emergency. The investigation found that it was decisive that an early decision was made to evacuate the technicians and the crew, even though this decision might have exposed the technicians to danger when they were leaving the vessel by means of ladders or jumping into a life raft.

Because the technicians had acquired detailed knowledge about the onboard emergency procedures, they were able to act quickly. This in turn permitted the crew to focus quickly 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 was operated in stressing circumstances, the risk of incorrect operation increased, and the consequences might be serious, because with fires time was of the utmost importance, especially on board relatively small aluminium vessels.

In this particular fire it had been 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 was, however, connected with a considerable risk because a suddenly arising leakage could have fatal consequences.

The investigation found that a CO2 system must not only be accompanied by an intuitive manual, but also be accompanied by information stating what was expected to happen when the system was activated. The fire-fighting strategy would also have to contain information about the actions to be made following use of the system.