The safety of Ro-Ro vessels in the light of the probabilistic concept for standardizing unsinkability

Abstract

This presentation concerns the probabilistic concept for the standardization of the unsinkability of ships, based on the assurance of an appropriate probability for the survival of collission.

Emphasis has been put on the buoyancy version of this approach, which has also been applied to Ro-Ro vessels. The probability of collision survival has been calculated for 19 Ro-Ro vessels built in various countries during the past few years. It has been concluded from this analysis that the retention of a buoyancy reserve following collision cannot be the basis for the standardization of the unsinkability of vessels of this type. The main safety factor for vessels of this type is stability in the damaged condition and that should be the basis for standardizing unsinkability.