Let’s start with the good news in the Australian Transport Safety Board, ATSB, report on the catastrophic crankcase fail, explosion and fire aboard Maersk Duffield in Moreton Bay, Queensland, Australia on 10 December 2009:
“The decision to use the ship’s fixed CO2 fire extinguishing system was prudent and the prompt use of the ship’s fire dampers, remote valves and emergency stops almost certainly reduced the severity of the damage to the generator room… Engine room re-entry and ventilation did not occur until after it had been determined that the fire was extinguished and that it was safe to do so. This occurred almost 3 hours after the fire had started”.
In this case the fire had initially been attacked with hoses and extinguishers until the Chief engineer decided that the fire was too big and that the CO2 system should be used.
Fire spreads with astonishing speed and time is everything. In this case the chief engineer decided, at the right moment, to use the CO2 system and acted promptly.
While CO2 is a very effective smothering agent flammable material may still be above the temperature at which it will self-ignite for a long time afterwards. Letting air reach that material can set the fire off again.
CO2 should left alone to do its job and left long enough, sometimes hours, to ensure that flammables are below their re-ignition temperature.
Here is how it went down: