Regulation 14

The off-shore supply vessels whose characteristics render compliance with regulation 13 impossible shall comply with the following criteria unless the Certifying Authority is satisfied that operating experience justifies departure therefrom: ( a ) the area under the righting lever curve (GZ curve) shall not be less than 0.070 metre-radians up to 15 degrees angle of heel when the maximum righting lever GZ max occurs at angle of heel of 15 degrees and 0.055 metre-radians up to 30 degrees angle of heel when the maximum righting lever GZ max occurs at angle of heel of 30 degrees and above. Where the maximum righting lever GZ max occurs at angle of heel between 15 degrees and 30 degrees, the corresponding requisite area under the righting lever curve shall be determined by the use of the formula: Area = 0.055 + 0.001 (30 degrees – θ max ) Where θ max is the angle of heel at which the righting lever curve reaches its maximum; ( b ) the area under the righting lever curve (GZ curve) between the angle of heel of 30 degrees and 40 degrees or between the angle of heel 30 degrees and θ f if this angle is less than 40 degrees, shall be not less than 0.03 metre-radians; ( c ) the righting lever GZ shall be at least 200 millimetres at an angle of heel equal to or greater than 30 degrees; ( d ) the maximum righting lever GZ max shall occur at an angle of heel not less than 15 degrees; and ( e ) the initial transverse metacentric height GM shall not be less than 150 millimetres.