Probabilistic approach for collision risk analysis of powered vessel with offshore platforms

The continuous increase in marine traffic and the construction of several offshore installations has led to a serious concern regarding the risks to offshore platforms from ship collisions. The main aim of this study was to carry out a probabilistic collision-risk analysis for offshore platforms exposed to powered collisions with passing vessels using an automatic identification system (AIS) database. The paper first describes the statistical distribution of the ship traffic under study and then considers how this information can be effectively used to estimate collision frequencies and impact energies for various categories of vessel, based on a simple probabilistic method. The effects of various collision mitigation measures, such as the use of enhanced collision alarming devices and the ability of platforms to rotate using thrusters, are considered in the frequency calculations. The risk method presented in this paper can be applied in the design and development phase of both new and existing platforms.