The importance of first-principles tools in estimating passenger ship safety

A passenger ship’s design is a multifaceted process that involves numerous aspects of marine engineering and naval architecture with the main goals being, performance, functionality, safety and cost. Between these, safety is a crucial component with passengers’ safety a top priority. Ship safety requires accurate assessment using a suitable measure from the beginning of the design process. For this purpose, the Potential Loss of Life can be used to assess safety from a risk perspective. However, multiple levels of reliability can be achieved in the final assessment of flooding risk, de-pending on the approximations and assumptions made in evaluating the consequences of a given hazard. This relates principally to assessing the dynamic stability of a damaged ship in waves and to the different tools employed for such assessment. The conventional approach of designers relies on the execution of simplified static analyses whilst the indications shown by years of research suggest the application of first-principle tools. The present work highlights the importance of performing damage stability calculations based on rigorous hydrodynamic modelling of the motion of a damaged ship to achieve a more reliable estimation of the safety level. The conclusions are endorsed by reporting the results of conventional and first-principles risk analysis on a set of reference passenger ships.