49.—(1) Every ship shall be provided with an efficient pumping plant capable of pumping from and draining any watertight compartment in the ship, other than a space permanently appropriated for the carriage of fresh water, water ballast or oil and for which other efficient means of pumping or drainage is provided, under all conditions likely to arise in practice after a casualty, whether or not the ship remains upright.
(ii)Wing suctions shall be provided if necessary for that purpose.
(iii)Efficient arrangements shall be provided whereby water in any watertight compartment may find its way to the suction pipes.
(iv)Efficient means shall be provided for draining water from all insulated holds and insulated between-decks in such a ship; provided that the provision for drainage may be omitted in a particular compartment if—
(a)according to the calculations made in accordance with the conditions set out in Schedule 3 in Merchant Shipping Notice MSN 1698 (M) the safety of the ship will not be impaired; and
(b)that the provision of drainage would otherwise be undesirable.
(2) Sanitary, ballast and general service pumps having a capacity in accordance with paragraph 4(3) of Schedule 6 in Merchant Shipping Notice MSN 1698 (M) may be accepted as independent power pumps if fitted with the necessary connections to the bilge pump systems.
(3) All tanks forming part of the structure of the ship and all watertight compartments, not being part of the machinery space, shall be provided with efficient sounding arrangements which shall be protected where necessary against damage.