Generic risk models for ship inspection based on readily available information

Inspection and survey provide the lines of defence for eliminating high risk ships from the world fleet. Administration and classification societies are targeting ships for inspection/survey mainly based on parameters that are correlated to the condition of ship, such as ship type, age, size, flag, and related performance monitored in the past. The aim of the EU funded research project SAFEPEC is to improve the targeting process by developing a methodology for identifying ships by means of a risk analysis. For this methodology the following elements are considered: • Causes for degradation • Vulnerability of the ship / system to degradation • Consequences for the ship /system • Inspection. The main challenge for this development lies in balancing on the one side the objective of evaluating a larger group of ships, and on the other side the objective of assessing the risk accurately for each ship based on the available information, i.e. using exclusively data that is generally available. This paper outlines the developed models for the first two elements, causes and vulnerability. In the context of inspection/survey only causes are relevant that could be detected by inspection. Therefore, for the cause model the focus was put on the main time dependent degeneration processes corrosion and fatigue, and, exemplarily for on-board systems, on life-saving appliances. The vulnerability module estimates the effect of these “causes” on the probability of failure, for which representative limit state functions were developed.