Ever since local application systems protecting engines and other high risk objects in the engine room were introduced in SOLAS, and came into force from 2002, water mist has become a main way of fighting onboard fires.
Now, the IMO has approved a revised standard for water mist system protecting the entire engine room. In this new standard, the IMO MSC/Circ. 1165, water mist can be used as an alternative to, for instance, CO2. However, all such water mist systems have restrictions with respect to volume – the systems with the largest approved volumes are at 3,000 to 4,000 cubic metres.
Water mist systems have proven their success in numerous test fires and also in several real fires. We expect this to continue with the new standard. There are also challenges mainly related to precision components that are not always suitable for marine operations. However, DNV GL actively follows up all findings from our surveys and information brought to our attention from shipowners on these matters, to ensure that these important systems have a high degree of reliability.