4.1 Criteria regarding righting lever curve properties
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Statutory Documents - IMO Publications and Documents - Circulars - Maritime Safety Committee - MSC.1/Circular.1281 – Explanatory Notes to the International Code on Intact Stability, 2008 – (9 December 2008) - Annex – Explanatory Notes to the International Code on Intact Stability, 2008 - Chapter 4 – Guidance for the Application of the 2008 IS Code - 4.1 Criteria regarding righting lever curve properties

4.1 Criteria regarding righting lever curve properties

 For certain ships the requirement contained in paragraph 2.2.3 of part A of the Code may not be practicable. Such ships are typically of wide beam and small depth, indicatively B/D ≥ 2.5. For such ships Administrations may apply the following alternative criteria:

  • .1 the maximum righting lever (GZ) should occur at an angle of heel not less than 15°; and

  • .2 the area under the curve of righting levers (GZ curve) should not be less than 0.070 metre-radians up to an angle of 15° when the maximum righting lever (GZ) occurs at 15° and 0.055 metre-radians up to an angle of 30° when the maximum righting lever (GZ) occurs at 30° or above. Where the maximum righting lever (GZ) occurs at angles of between 15° and 30°, the corresponding area under the righting lever curve should be:

  • 0.055 + 0.001 (30° - ϕmax) metre-radiansfootnote.


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