Ship safety against capsizing and IMO stability criteria

First aim of this paper is to provide the naval architects with a suitable tool to optimise hull design in the preliminary design stage, not only hydrodynamically, as it is traditionally made and it is possible for the methodical hull series, but also looking at the transverse standard stability. By means of the analysis of the results obtained for the sistematic hull series the author's second aim is to show the influence of the geometrical and loading parameters on the I.M.O. stability criteria and the validity of these criteria, already adopted by many Administrations, in verifying ship's safety level against capsizing. By taking into account the comparison between weather stability criterion and the statistical criteria whose results have already been analysed in previous papers, the authors think that the stability statistical criteria, undoubtedly the easiest to apply, could be applied also in the next future in order to verify ship's intact stability with suitable modifications.