The Intact Ship Stability Code: Present Status and Future Developments

Provisions concerning intact ship stability have been introduced at a later stage in international regulations of ship safety. The General Stability Criteria based on righting arm characteristics was adopted in 1968 and the Weather Criterion was adopted in 1985. Both criteria were based on ideas, concepts and ship typologies/dimensions, existing long before their adoption, so that the need of their upgrading and of implementing the important developments of ship dynamics, with particular emphasis on nonlinear aspects, assumed an increasing importance. The revision of the Intact Stability Code, IMO Res. A.749, was started in 2001 and the first step, consisting in an important structural reorganization and in the development of an alternative way on experimental basis to fulfil the requirements of Weather Criterion for ships having parameters outside the original range, was completed in 2007. In this paper, the present state of the art of revision of Intact Stability Code is presented in detail, together with the indication of the short term expected developments and of the general guidelines which will be adopted to drive the long term developments.