Artikel 21

(1) Where air pipes to tanks and void spaces below deck extend above the working or the superstructure decks, the exposed parts of the pipes shall be of strength equivalent to the adjacent structures and fitted with appropriate protection. Openings of air pipes shall be provided with means of closing, permanently attached to the pipe or adjacent structure.
(2) The height of air pipes above deck to the point where water may have access below shall be at least 760 millimetres on the working deck and at least 450 millimetres on the superstructure deck. The Administration may accept reduction of the height of an air pipe to avoid interference with the fishing operations.