The Merchant Shipping (Passenger Ship Construction: Ships of Classes III to VI(A)) Regulations 1998

Stability in the damaged condition

33.—(1) This regulation applies to all subdivided ships constructed before 29th April 1990.

(2) (a) (i) In addition to the requirements of regulation 30 every ship shall be so constructed as to provide sufficient intact stability in all service conditions to enable the ship to withstand the flooding of any one of the main compartments into which the ship is subdivided in accordance with the requirements of regulation 32.

(ii) If two of the main compartments, being adjacent to each other, are separated by a bulkhead which is stepped under the conditions of paragraph 4(3)(a) of Section 2 of Schedule 2 in Merchant Shipping Notice MSN 1699(M), the intact stability shall be adequate to withstand the flooding of those two adjacent main compartments.

(b) Where in any ship in relation to which the factor of subdivision required by regulation 32 is 0.50, the intact stability shall be adequate to withstand the flooding of any two adjacent main compartments.

(3) (a) For the purposes of this regulation the sufficiency of the intact stability shall be determined in accordance with the provisions of sections 1 and 2 in Schedule 3 in Merchant Shipping Notice MSN 1699(M).

(b) (i) The intact stability of every ro-ro passenger ship shall be re-examined in accordance with the provisions of sections 2 or 3 of Schedule 3 as appropriate in Merchant Shipping Notice MSN 1699(M) in order to establish the sufficiency of positive stability provided as required by sub-paragraphs (2)(a) and (3)(a) whenever considered necessary in connection with amended stability information prepared in accordance with regulation 31(4) and (5).

(ii) Such re-examinations shall demonstrate that at all stages of flooding there is sufficient positive residual stability after the assumed damage prescribed in section 1 of Schedule 3 in Merchant Shipping Notice MSN 1699(M).

(4) (a) (i) Every ship shall be so constructed as to keep asymmetrical flooding, when the ship is in a damaged condition, at the minimum consistent with efficient arrangements.

(ii) If cross-flooding fittings are provided in any such ship the fitting shall, where practicable, be self-acting but in any case where controls to cross-flooding fittings are provided, they shall be capable of being operated from an accessible position above the bulkhead deck.

(iii) Such fittings together with their controls as well as the maximum heel before equalisation shall be such as will not endanger the safety of the ship.

(iv) The cross-flooding fittings shall be capable of reducing the heel within 15 minutes sufficiently to meet the requirements of sub-paragraph 2(b)(iii) of sections 2 or 3 of Schedule 3 as appropriate in Merchant Shipping Notice MSN 1699(M).

(b) If the margin line may become submerged during the flooding assumed for the purposes of the calculation referred to in Schedule 3 in Merchant Shipping Notice MSN 1699(M), the construction of the ship shall be such as will enable the master of the ship to ensure—

(i) that the maximum angle of heel during any stage of such flooding will not be such as will endanger the safety of the ship; and

(ii) that the margin line will not be submerged in the final stage of flooding.

Requirements for subdivided ships constructed on or after 29th April 1990

(5) Every ship shall comply with the provisions of paragraphs (1) to (4) except that—

(a) for the purpose of paragraph (3)(a) the sufficiency of intact stability shall be calculated in accordance with section 1 and 3 of Schedule 3 in Merchant Shipping Notice MSN 1699(M); and

(b) the heel referred to in paragraph (4)(a) shall not exceed 15 degrees and the cross-flooding fittings shall be capable of meeting the requirements of section 3(2)(c) of Schedule 3 in Merchant Shipping Notice MSN 1699.