[BITList] Fw: ballast

[HUGH]

Colin,

MCA Rules, 5.2.2.9, state:

The nature, amount and distribution of any permanent ballast is to be shown in the lightship condition in the Stability Information Book.
  1.. If ballast consists of either oil or water, means shall be provided to prevent its accidental use or transfer. This may be achieved by fitting a spectacle blank in the suction line to each tank containing the ballast.
  2.. Solid ballast should be efficiently stowed, and fixed against movement, and should not be fitted in the double bottom tanks or any other confined space, because of the difficulties in surveying the structure, unless it is necessary to achieve the desired improvement in stability. When it is proposed to fit solid ballast in such spaces, the surveyor should warn the owners that it may be necessary to remove some or all of the ballast in the future, in order that surveyors may examine the internal structure.
>From this it might appear that solid ballast of whatever kind would have to be packaged.  Drilling mud doesn't fit easily with the above.
 
Bureau Veritas Rules, 1.2, state:

1.2.1 If used, permanent ballast is to be located in accordance with a plan approved by the Society and in a manner that prevents shifting of position. Permanent ballast is not to be removed from the ship or relocated within the ship without the approval of the Society. Permanent ballast particulars are to be noted in the ship's stability booklet.
1.2.2 Permanent solid ballast is to be installed under the supervision of the Society.

One website (can't open it - runtime errors) says permanent ballast is usually solid lead castings.

Why would a properly designed vessel need solid ballast in addition to normal ballast?

Hugh.


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