Amount of cleaning a cargo space would require ,mostly depends up on What was the cargo the ship previously carried & that which is to be loaded.
As a general guidelines holds should be clean, dry ,free from any traces of previous cargo and well ventilated before the cargo is received.
Dunnage which was used for the previous cargo should be removed & after cleaning should be laid back after discarding the damaged one. Bagged cargo requires widely sized dunnages. This is mainly to improve Air circulation between the stacks of bags.CLEANING:
SPAR CEILING & CARGO BATTENS ( SIDE BATTENS)
Cargo battens, as they are called comprise portable wooden battens fitted to the inner edge of the side frames. So that an inner barrier is created to prevent cargoes touching shipside & to enhance ventilation within cargo hold. This is done to avoid cargo damage due to absorption of moist being in touch with ship-sweat.
A through sweeping has to be done and rubbish of previous cargo is removed.
BILGES must be cleaned & rose box ( strum box) is cleaned for better bilge suction. If the hold is required to be washed down ( for bulk carrier) then It is a prudent idea that bilges are cleaned beforehand & bilge pump tried out.
It is customary to wash the hold with fresh water after washing with sea water.
A thorough ventilation of cargo hold is necessary by mechanical vents fitted with cargo holds.
In the dry bulk trades, there are essentially five grades of hold cleanliness:
hospital clean, or ‘ stringent’ cleanliness
grain clean, or high cleanliness
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