Ice Class and Ice‐Going Merchant Ships

Abstract

Abstract Merchant ships first started year‐round operations in the Baltic Sea in the late 1870s with seaborne trade between northern Finland and Stockholm, Sweden. Ice class rules are principally features that enhance the ship's capability to navigate in ice; however, they should also take into account the environment and the type of operation that the ship is undertaking. The first Finnish ice class rules were introduced in 1890. Ice class rules and regulations have generally been developed by countries whose ports and harbours are closed in the winter season due to ice, and today's Finnish‐Swedish ice class rules (FSICR) have been adopted by members of the International Associations of Classification Societies (IACS) as the de facto standard for first‐year ice requirements. First‐year ice is sea ice that is present only during the winter season; in late spring/early summer the ice melts completely. As the ice has only one winter to accumulate, the ice has relatively low ice strength properties. Typically, first‐year ice conditions are found in the Baltic Sea and the St. Lawrence Seaway. Multi‐year ice is ice that has survived at least one summer and may be 3 m or more in thickness. The ice is usually much stronger than first‐year ice and is found in parts of the Arctic Ocean and Antarctica. This document will also contain an overview of some of the different types of ice‐going vessels and their different areas of operation, but will predominately focus on ships operating in winter conditions in the northern Baltic Sea.