The commonest form of dirt in holds are hydrocarbons: oils, diesel, greases, as well as stagnant water which sometimes carries microorganisms. These hydrocarbons are emulsified and evacuated through the use of solvent-based cleaners. <br>It should be noted that a biodegradable product does not make the dirt biodegradable. Discharging cleansing waters into the sea is always a source of pollution. The cleansing is rounded of with a deodorant, which destroys the microorganisms responsible for disagreeable odours. <br>Non anodised aluminium decks must be washed outside the craft.