Sammendrag
This paper describes a model to estimate the frequency of near collision situations between ships, which can be an indication of collision risk. The proposed model uses several risk indicators to identify near-miss situations, such as Automatic Identification System (AIS) data, ship domain, speed, rate of turn, ship type and more. The model utilizes a ship domain approach to find potential near collision situations. If a ship domain was violated and a last-moment evasive manoeuvre was performed, the situation is identified as a near-collision (identified by an abnormal ship rate-of-turn (ROT)). With the new model a case-study is performed at an area in Vestfjorden in North-Norway for a three-year period. The case-study detected 476 ship domain violations and 46 near collision. All detected nearcollisions were graphically plotted and examined; from the 47 detected situations, 19 were positively identified as near-collisions. The conclusion is that the current state of the model, with the uncertainties in both dataset and model, should be considered as a risk indicator that can be used to identify areas of interest for further risk assessment, and has a potential to become a solid risk assessment tool with further development.