Sometimes, when the ballasting of a ship laden with bulk
grain is necessary in order to meet the stability requirements of
this chapter, ballast cannot be taken at the point of loading because
of a water depth limitation or the unsuitability of the harbour water.
In such cases, the ship takes on ballast after leaving the loading
berth but before proceeding on the high seas. The reverse situation
also occurs with respect to deballasting upon completion of a voyage.
The regulations, neither in chapter VI nor
in any other part of the Convention, identify a point in the voyage
at which full compliance commences. The following guideline is intended
to describe the usual practice with respect to this question.