Ice classes of ships

The Finnish and Swedish maritime authorities have elaborated and issued Finnish-Swedish ice class regulations (or rules, FSICR) since 1971. The regulations have also been incorporated into the rules of the classification societies.

In Finnish law, provisions on ice classes are included in the Act on the Ice Classes of Ships and Icebreaker Assistance (1121/2005). The year of build of a ship determines which set of regulations apply to the ship. Provisions on the application of the varoius sets of regulations are laid down in the 2010 regulations. 

The ice class regulations define the minimum engine output, hull strength, machinery and rudder strength of ships navigating in ice. The ice class affects the net tonnage of the ship, which in turn forms the basis for determining the size of the fairway due to be charged. When restrictions concerning icebreaker assistance are imposed, it depends on the ice class whether a ship is entitled to assistance or not.

The aim of the regulations is to ensure that ships operating in the Baltic Sea are capable of navigating in ice and winter navigation runs safely and smoothly.

List of equivalences

Trafi has issued a regulation on which Finnish ice classes are equivalent to the class notations of recognized classification societies (the so called list of equivalences). If a ship has an ice class notation of a recognized classification society, it is granted one of the Finnish ice classes IA Super, IA, IB, IC, II and III in accordance with the equivalence list.

The regulation also includes provisions on documentation required for the determination of the ice classes of ships.

Winter navigation studies

Continuous research and development is required to keep the ice class regulations up to date with the latest developments in ship construction. During the past few years research efforts have centered on issues related to the regulations concerning hull strength and rudder machinery. Studies on ice forecasting and the smoothness of winter navigation have been carried out as joint efforts of various research institutes.

Research relating to winter navigation is financed by Trafi, the Finnish Transport Agency and the Swedish maritime authorities.