Analysis of ship domains in traffic separation schemes

The ship domain is a criterion of safety assessment in ship encounter situations. This criterion allows us to identify dangerous situations in open sea and restricted areas, the latter characterized by natural limitations such as the shore line, or artificial ones e.g., boundaries of Traffic Separation Schemes (TSSs). This article analyzes ship domains in TSSs. These schemes, being established in areas where vessel traffic is intensive, as a rule have virtual traffic lanes that indicate the direction of vessel traffic flow. The influence of the ship size and type on domain shape and size in a TSS has been examined. The domains have been defined on the basis of AIS data and statistical methods. The analyzed ship domains have been approximated by ellipses. The authors have determined intervals of changes in domain parameters.