Safety is of paramount concern to passenger ship owners and integral to their reputation. For this reason, passenger ship owners are aiming for safety standards well beyond the statutory requirements. The current methods for assessing ship survivability following hull breach and subsequent flooding, adopt a simplified application to define a complex issue leading to uncertainty and over-design. This study uses high fidelity deterministic Computational Fluid Dynamics (CFD) analysis in order to explore the shortfalls of the current design guidance such as SOLAS. A number of flooding scenarios are modelled on a cruise ship at full scale for calm and rough seas.