Validation of the new risk based design approaches (Polaris) for arctic and antarctic operations

Selection of suitable ice class for ships operation is an important but not simple task. The process of selecting an appropriate ice class is of high importance both from a safety as well as an economical perspective, but the selection process is still based on accumulated experience and traditions within the areas of existing operations. The increased exploitation of the Polar waters, both seasonal periods and geographical areas, as well as the introduction of new international design standards such as Polar Code, reduces the relevancy of using existing experience as basis for the selection, and new methods and knowledge have to be developed. This paper will critically review the current knowledge of applying risk based design methodologies for ice covered waters. To illustrate the current best practice, the new polar code and especially the new Polar Operational Limit Assessment Risk Indexing System (POLARIS) is applied for two vessels: one navigating independently in the Antarctica (SA Agulhas II) and one navigating with icebreaker assistance on the Kara Sea on the Russian Arctic (MT Uikku) to evaluate the suitable ice class for these waters. It is found the PC 3 is the most suitable ice class for ships navigating in harsh Antarctic ice conditions and PC 6 is enough behind an icebreaker on the Kara Sea during hard winter conditions.