Column-stabilized units
Clasification Society 2024 - Version 9.40
Statutory Documents - IMO Publications and Documents - International Codes - 1989 MODU Code – Code for the Construction and Equipment of Mobile Offshore Drilling Units, 1989 – Resolution A.649(16) - Chapter 3 – Subdivision, Stability and Freeboard - 3.7 Freeboard - Column-stabilized units

Column-stabilized units

  3.7.20 The hull form of this type of unit makes the calculation of geometric freeboard in accordance with the provisions of chapter III of the 1966 Load Line Convention impracticable. Therefore the minimum freeboard of each column-stabilized unit should be determined by meeting the applicable requirements for:

  • .1 the strength of the unit's structure;

  • .2 the minimum clearance between passing wave crests and deck structure (see 2.6.1 to 2.6.3); and

  • .3 intact and damage stability requirements.

  3.7.21 The minimum freeboard should be marked in appropriate locations on the structure.

  3.7.22 The enclosed deck structure of each column-stabilized unit should be made weathertight.

  3.7.23 Windows, sidescuttles and portlights, including those of the non-opening type, or other similar openings should not be located below the deck structure of column-stabilized units.

  3.7.24 Administrations should give special consideration to the position of openings which cannot be closed in emergencies, such as air intakes for emergency generators, having regard to the intact righting arm curves and the final waterline after assumed damage.

Parent topic: 3.7 Freeboard
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