Tank means and enclosed space which is formed by the permanent structure of a ship and which is designed for the carriage of liquid in bulk.
Wing tank means any tank adjacent to the side shall plating.
Centre tank means any tank inboard of a longitudinal bulkhead.
Slop tank means a tank specifically designated for the collection of tank draining, tank washings and other oily mixtures.
Clean ballast means the ballast in a tank which, since oil was last carried therein, has been so cleaned that effluent there from if it were discharged from a ship which stationary into clean calm water on a clear day would not produce visible traces of oil on the surface of the water or on adjoining shore lines.
