Division EXISTING CLASS A AND B SHIPS OF 24 METRES IN LENGTH AND ABOVE:F1

All existing class A and B ships shall, in all loading conditions, satisfy the following stability criteria after due correction for the effect of free surface of liquids in tanks in accordance with the assumptions of paragraph 3.3 of IMO Resolution A.749(18) as amended, or equivalent.

1. (a)

   The area under the curve of righting lever (GZ curve) shall not be less than:

   1. (i)

      0,055 metre-radians up to an angle of heel of 30 °;

   2. (ii)

      0,09 metre-radians up to an angle of heel of either 40 ° or the angle of flooding, i.e. the angle of heel at which the lower edges of any openings in the hull, superstructures or deckhouses, being openings that cannot be closed weathertight, are immersed, if that angle be less than 40 °;

   3. (iii)

      0,03 metre-radians between the angles of heel of 30 ° and 40 ° or between 30 ° and the angle of flooding if this angle is less than 40 °;

2. (b)

   The righting lever GZ shall be at least 0,20 metre at an angle of heel equal to or greater than 30 °.

3. (c)

   The maximum righting lever GZ shall occur at an angle of heel preferably exceeding 30 ° but not less than 25 °.

4. (d)

   The initial transverse metacentric height shall not be less than 0,15 metre.

The loading conditions to be considered in order to verify the compliance with the above stability criteria shall include at least those listed in paragraph 3.5.1.1 of IMO Resolution A.749(18), as amended.

All existing ships of classes A and B having a length of 24 metres and over shall also comply with the additional criteria as given in IMO Resolution A.749(18), as amended, paragraph 3.1.2.6 (additional criteria for passenger ships) and paragraph 3.2 (Severe Wind and Rolling Criterion).

Where Member States consider the application of the Severe Wind and Rolling Criterion of IMO Resolution A.749(18), as amended, inappropriate, an alternative approach to ensuring satisfactory stability may be applied. This should be supported by evidence to the Commission which confirms that an equivalent level of safety is achieved.