Notwithstanding the provisions of Regulation III/8(1)(a) and (b) the following icing allowance shall be made in the stability calculations for vessels operating in the area north of latitude 63° N, between longitude 28° W and longitude 11° W: (a) 40 kilograms per square metre on exposed weather decks and gangways; (b) 10 kilograms per square metre for projected lateral area of each side of the vessel above the water plane.