2 Freeboard
Clasification Society 2024 - Version 9.40
Statutory Documents - IMO Publications and Documents - Circulars - Maritime Safety Committee - MSC/Circular.608/Rev.1 – Interim Guidelines for Open-top Containerships – (Adopted on 5 July 1994) - Annex - Interim Guidelines for Open-Top Containerships - 2 Freeboard

2 Freeboard

  2.1 Minimum freeboard should be determined by seakeeping characteristics and stability. Model tests and calculations should be carried out to provide Administrations with:

  • .1 measured data for the maximum hourly rate of ingress of green water likely to be shipped into each cargo hold;

  • .2 evaluation of the adequacy of the discharge rates from cargo hold freeing ports (if they are fitted).

  2.2 The maximum hourly rate of ingress of green water in any one open hold determined from model testing should not exceed the hatch opening area multiplied by 400 mm/hour.

  2.3 A conventional geometrical freeboard and minimum bow height should be calculated assuming that hatch covers are fitted. Under no circumstances should a freeboard and bow height be assigned to an open-top containership which is less than the equivalent geometrical freeboard determined from the LL 1966.

  2.4 All seasonal freeboards should be omitted unless the minimum geometrical freeboard and corresponding seasonal freeboards for which the ship is eligible (assuming hatch covers fitted) are greater than the freeboard for which the model tests were satisfactorily carried out. In that case, the minimum geometrical freeboard and the corresponding seasonal freeboards greater than the freeboard for which the model tests were carried out should be assigned.

  2.5 The minimum freeboard and minimum bow height assigned to the ship should not be less than those corresponding to the model test conditions.


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