An integrated quantitative risk assessment of an oil carrier

Class Societies have traditionally taken an experience based approach to developing Class Rules that has provided a high level of safety for both personnel and the environment. With emerging technologies and advanced designs, however, the experience base is small. A risk-based approach to Classification is being developed by the American Bureau of Shipping (ABS) to ensure that the high level of safety that currently exists continues, and will be extended to new and novel designs. As part of this effort, an integrated Quantitative Risk Assessment (QRA) model for an oil carrier was developed. The basic design modeled is that of a double hulled, redundant propulsion/rudder vessel. This model is being used to evaluate the "value" of Class Rules, evaluate the relative benefit of redundancy, and the risk impact of maintenance while underway. This paper will present the basic design and methodology used to build the model, along with results from the applications performed.