Damage Stability of Ro-Ro Passenger Ships: Investigations about The \u2018Water On Deck\u2019 issues within Safety Rules

Ro-Ro passenger ships engaged in regular international voyages, to or from Europe member states, have to fulfil the directive 2003/25/EC, which requires the compliance with SOLAS 90, Regulation II-1/B/8 paragraph 2.3 to 2.3.4, with the defined amount of water on deck (this criterion is also known as Stockholm Agreement\u201d requirement). At the same time, after a long period of review and development at IMO, the probabilistic SOLAS 2009 is at present the new regulation for the damage stability assessment of a ship. The point is that SOLAS 2009 doesn\u2019t take into account the effect of water on deck. Therefore a further improvement in SOLAS2009, involving the water on deck issue is in the Agenda of IMO SLF Committee and several Administrations and research groups have carried out calculations and analysis in order properly face the issue. The question is still open. In this paper, some damage stability investigations for real ship within the probabilistic approach are carried out in order to observe the influence on results of the inclining moment due to the presence of water on the garage deck; the water amount and the application modality are identified within the paradigm of the Stockholm agreement requirements but then they are properly \u201ctranslated\u201d into the probabilistic approach. This lesson should be a contribute to the common knowledge on the matter A further insight into the problem is gained performing parametric calculations for different Ro-Ro ship sizes, addressing specifically the influence of ship size with special attention to the different residual freeboard values