Regulation 8 - Special requirements concerning passenger ship stability
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Statutory Documents - IMO Publications and Documents - International Conventions - SOLAS - International Convention for the Safety of Life at Sea - Chapter II-1 - Construction - Structure, subdivision and stability, machinery and electrical installations - Part B-1 - Stability - Regulation 8 - Special requirements concerning passenger ship stability

Regulation 8 - Special requirements concerning passenger ship stability

  1 A passenger ship intended to carry 400 or more persons shall have watertight subdivision abaft the collision bulkhead so that si = 1 for a damage involving all the compartments within 0.08L measured from the forward perpendicular for the three loading conditions used to calculate the attained subdivision index A. If the attained subdivision index A is calculated for different trims, this requirement shall also be satisfied for those loading conditions.

  2 A passenger ship intended to carry 36 or more persons is to be capable of withstanding damage along the side shell to an extent specified in paragraph 3. Compliance with this regulation is to be achieved by demonstrating that si, as defined in regulation 7-2, is not less than 0.9 for the three loading conditions used to calculate the attained subdivision index A. If the attained subdivision index A is calculated for different trims, this requirement shall also be satisfied for those loading conditions.

  3 The damage extent to be assumed when demonstrating compliance with paragraph 2, is to be dependent on the total number of persons carried, and L, such that:

  • .1 the vertical extent of damage is to extend from the ship's moulded baseline to a position up to 12.5 m above the position of the deepest subdivision draught as defined in regulation 2, unless a lesser vertical extent of damage were to give a lower value of si , in which case this reduced extent is to be used;

  • .2 where 400 or more persons are to be carried, a damage length of 0.03L, but not less than 3 m is to be assumed at any position along the side shell, in conjunction with a penetration inboard of 0.1B but not less than 0.75 m measured inboard from the ship side, at right angles to the centreline at the level of the deepest subdivision draught;

  • .3 where less than 400 persons are carried, damage length is to be assumed at any position along the shell side between transverse watertight bulkheads provided that the distance between two adjacent transverse watertight bulkheads is not less than the assumed damage length. If the distance between adjacent transverse watertight bulkheads is less than the assumed damage length, only one of these bulkheads shall be considered effective for the purpose of demonstrating compliance with paragraph 2;

  • .4 where 36 persons are carried, a damage length of 0.015L but not less than 3 m is to be assumed, in conjunction with a penetration inboard of 0.05B but not less than 0.75 m; and

  • .5 where more than 36, but fewer than 400, persons are carried the values of damage length and penetration inboard, used in the determination of the assumed extent of damage, are to be obtained by linear interpolation between the values of damage length and penetration which apply for ships carrying 36 persons and 400 persons as specified in subparagraphs .4 and .2.


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