Ice class rules like the Finnish-Swedish Ice Class Rules, Russian Maritime Register of Shipping ice rules and International Association for Classification Societies harmonized ice class (PC-)rules each contain an explicitly given or implicitly used definition of the design point. The design point specifies what the allowable limit response of the structure is and how often this limit is reached. Allowable limit responses are often characterized by Ultimate Limit State (ULS), Serviceability Limit State (SLS), Accidental Limit State (ALS) or Fatigue Limit State (FLS), see e.g. NORSOK (2004). It is important to note that in the design point only the frequency and the limit state are free parametres; loading for example follows in principle from the intended operational spectrum and the frequency.