Section 9 Navigation in ice

9.1.1 Where an ice class notation is to be included in the class of a craft, the scantlings will require to be specially considered. The additional requirements for operation in ice will, in general, be in accordance with LR’s Rules and Regulations for the Classification of Ships (hereinafter referred to as the Rules for Ships), Pt 8 Hull Construction in Composite, where appropriate, and also Pt 6, Ch 5, 7 Strengthening requirements for navigation in ice conditions, Pt 7, Ch 5, 7 Strengthening requirements for navigation in ice conditions and Pt 8, Ch 5, 6 Strengthening requirements for navigation in ice conditions for steel, aluminium and composite construction respectively.

9.1.2 It is the responsibility of the Owner to determine which ice class notation is most suitable for their requirements.

9.1.3 The strengthening requirements detailed in this Section are applicable to craft, other than those assigned the notation HSC and/or LDC (see Pt 1, Ch 2 Classification Regulations), intended for operation in first-year ice conditions.

9.1.4 For a multi-hull craft, special consideration is to be given to the interaction of the ice between the hulls.

9.1.5 The requirements of this Section assume that, when approaching ice-infested waters, the craft’s speed will be reduced appropriately. The vertical extent of ice strengthening for craft intended to operate in ice conditions at speeds exceeding 15 knots will be specially considered.

9.2.1 Side scuttles are not to be situated in the ice belt.

9.2.2 If the weather deck in any part of the craft is situated below the upper limit of the ice belt, the bulwark is to be reinforced to the same degree as the shell plating in the main ice belt.

9.3.1 A transom stern is not normally to extend below the ice load waterline. Where this cannot be avoided, the transom is to be kept as narrow as possible and the scantlings of plating and stiffeners are to be as required for the midcraft region.

9.4.1 For craft with two or more propellers, shafting and sterntubes are generally to be enclosed within plated bossings. If detached supporting struts are necessary, their design, strengthening and attachment to the hull will be specially considered.

9.5.1 For water jets, special consideration is to be given to the potential intake of ice pieces into the impeller causing additional loads and strengthening of steering buckets.