What is Stability booklet and what information we get from Stability booklets?

Each ship should be provided with a stability booklet, approved by the Ad- ministration, which contains  sufficient information to enable the master  to operate  the ship in compliance with the applicable  requirements contained in the  Code.  The Administration may have additional requirements. On a mobile offshore drilling  unit,  the  stability booklet  may  be referred  to as an  operating manual.

The  stability booklet  may  include  information on longitudinal strength.  This  Code addresses  only the  stability-related contents of the booklet.

The format of the stability booklet and the information included will vary dependent on the  ship  type and  operation.  In  developing  the  stability booklet,  consideration should be given to including the following information:

  1. A general description of the ship;
  2. Instructions on the use of the booklet;
  3. General arrangement plans showing  watertight compartments,  closures, vents,  down flooding angles, permanent ballast, allowable deck loadings and freeboard  diagrams;
  4. Hydrostatic curves  or tables  and  cross curves  of stability calculated on  a  free-trimming basis,  for the  ranges  of displacement and  trim anticipated in normal  operating conditions;
  5. Capacity  plan or tables  showing capacities  and centres  of gravity for each cargo stowage space;
  6. Tank  sounding  tables  showing capacities,  centres  of gravity,  and free surface data  for each tank;
  7. Information on loading  restrictions, such as maximum  KG or mini- mum  GM curve or table  that can be used to determine  compliance with the applicable  stability criteria;
  8. Standard operating conditions  and examples for developing other  acceptable  loading  conditions  using  the  information contained in the stability booklet;
  9. A brief  description of the  stability calculations   done  including  assumptions;
  10. General precautions for preventing unintentional flooding;
  11. Information concerning  the use of any special cross-flooding fittings with  descriptions   of damage  conditions   which  may  require  cross- flooding;
  12. Any other necessary guidance for the safe operation of the ship under normal  and emergency  conditions;
  13. A table  of contents and index for each booklet;
  14. Inclining test report  for the ship, or:
    • Where the stability data is based on a sister ship, the inclining test report  of that sister  ship along with  the  lightship  measurement report  for the ship in question;  or
    • Where  lightship   particulars  are  determined  by  other  methods than  from inclining  of the  ship  or its  sister,  a summary  of the method  used to determine those particulars;
  15. Recommendation for determination of ship’s stability by means of an in-service inclining test.



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