Watertight bulkhead, deck, doors, trunks, etc

(1) This regulation does not apply to such ships the hull of which is constructed of wood. (2) Each watertight subdivision bulkhead, whether transverse or longitudinal, shall be constructed in such a manner that it should be capable of supporting, with a proper margin of resistance, the pressure due to the maximum head of water which it might have to sustain in the event of damage to the ship but at least the pressure due to a head of water up to the margin line. The construction of these bulkheads shall be to the satisfaction of the Administration or a recognised organization. (3) Steps and recesses in bulkheads, shall be watertight and as strong as the bulkhead at the place where each occurs. (4) Where the frames or beams pass through a watertight deck or bulkhead, such deck or bulkhead shall be made structurally watertight to the satisfaction of the Administration. Merchant Ships (Registration) 129 (5) The number of openings in watertight bulkheads shall be reduced to the minimum compatible with the general arrangements and operational needs of the ship. Openings shall be fitted with watertight closing appliances to the satisfaction of the Administration. Watertight doors shall be of equivalent strength to the adjacent unpierced structure. (6) Watertight decks, trunks, tunnels, duct keels and ventilators shall be of the same strength as watertight bulkheads at corresponding levels. The means used for making them watertight, and the arrangements adopted for closing openings in them, shall be to the satisfaction of the Administration. Watertight ventilators and trunks shall be carried at least up to the freeboard deck. (7) Testing main compartments by filling them with water is not compulsory. When testing by filling with water is not carried out, a hose test is compulsory. In any case, a thorough inspection of watertight bulkheads shall be carried out. (8) The forepeak, double bottoms, including duct keels, and inner skins shall be tested with water to a head corresponding to the requirements of subregulation (2). (9) Tanks which are intended to hold liquids, and which form part of the subdivision of the ship shall be tested for tightness with water to a head corresponding to two-thirds of the depth from the top of keel to the margin line in way of the tanks provided that in no case shall the test head be less than 0.9m above the top of the tank. (10) The tests referred to in subregulation (8) and (9) are for the purpose of ensuring that the subdivision structural arrangements are watertight and are not to be regarded as a test of the fitness of any compartment for the storage of oil fuel or for other special purposes for which a test of a superior character may be required depending on the height to which the liquid has access in the tank or its connections. Merchant Ships (Registration) 130