Section 3 Air Environment
Clasification Society 2024 - Version 9.40
Clasifications Register Rules and Regulations - Rules and Regulations for the Classification of Offshore Units, July 2022 - Part 3 Functional Unit Types and Special Features - Chapter 6 Units for Transit and Operation in Ice - Section 3 Air Environment

Section 3 Air Environment

Parent topic: Chapter 6 Units for Transit and Operation in Ice

3.1 Air temperature

3.1.1 For units intended to operate in cold regions, the temperature on exposed surfaces is to be considered. See the Rules for the Winterisation of Ships, July 2022.

3.1.2 The average external design air temperature is to be taken as the lowest mean daily average air temperature in the area of operation:

where

Mean = statistical mean over a minimum of 20 years
Average = average during one day and one night
Lowest = lowest during the year
MDHT = Mean Daily High Temperature
MDAT = Mean Daily Average Temperature
MDLT = Mean Daily Low Temperature

Pt 3, Ch 6, 3.1 Air temperature 3.1.4 shows the definition graphically.

3.1.3 The lowest external design air temperature is to be taken as the lowest mean daily lowest air temperature in the area of operation. Where reliable environmental records for contemplated operational areas exist, the lowest external design air temperature may be obtained after the exclusion of all recorded values having a probability of occurrence of less than 3 per cent.

3.1.4 Lowest mean daily average air temperatures for the Arctic and Antarctic are provided in Pt 3, Ch 6, 3.1 Air temperature 3.1.4 to Pt 3, Ch 6, 3.1 Air temperature 3.1.4.

Figure 6.3.1 Air temperature

Figure 6.3.2 Lowest mean daily average air temperatures for the Arctic

Figure 6.3.3 Lowest mean daily average air temperatures for the Antarctic
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