Page 402 - statbility for masters and mates

390 Ship Stability for Masters and Mates
Part 1
SHIPS IN GENERAL
Structural Strength and Stability
2.-(1) The construction of the ship shall be such that her general structural strength will be suf®cient for the freeboards to be assigned to her.
(a) See section 18 of the Merchant Shipping (Safety Convention) Act 1949 (12,13 & 14 Geo. 6 c 43.) and section 14 of the Merchant Shipping Act 1964 (1964 c 47).
(2) The design and construction of the ship shall be such as to ensure that her stability in all probable loading conditions will be suf®cient for the freeboards to be assigned to her, and for this purpose regard shall be had, in addition to the intended service of the ship and to any relevant requirements of Rules made under the Merchant Shipping (Safety Convention) Act 1949(a) and the Merchant Shipping Act 1964(b), to the following criteria:
(a) The Area under the curve of Righting Levers (GZ curve) shall not be less than:
(i) 0.055 metre-radians up to an angle of 30 degrees;
(ii) 0.09 metre-radians up to an angle of either 40 degrees or the angle at which the lower edges of any openings in the hull, superstructures or deckhouses, being openings which cannot be
closed weathertight, are immersed if that angle be less;
(iii) 0.03 metre-radians between the angles of heel of 30 degrees and
40 degrees or such lesser angle as is referred to in (ii).
(b) The Righting Lever (GZ) shall be at least 0.20 metres at an angle of
heel equal to or greater than 30 degrees.
(c) The maximum Righting Lever (GZ) shall occur at an angle of heel not
less than 30 degrees.
(d) The initial transverse metacentric height shall not be less than 0.15
metres. In the case of a ship carrying a timber deck cargo which complies with sub-paragraph (a) by taking into account the volume of timber deck cargo the initial transverse metacentric height shall not be less than 0.05 metres.
(3) To determine whether the ship complies with the requirements of sub- paragraph (2) the ship shall, unless the Board otherwise permit, be subjected to an inclining test carried out in the presence of a surveyor appointed by the Board, and the Board shall notify the Assigning Authority whether or not they are satis®ed that the ship complies with those requirements.
(a) 194912,13&14Geo.6c.43. (b) 1964 c. 47.