4.1.1 For ship units, the design of construction details for primary members is to comply with Pt 10 Ship Units. For other unit types, the design of construction details for primary members is to comply with Pt 3, Ch 10, 4 Construction details for primary members of the Rules for Ships.
4.1.2 Additional requirements with respect to unit types as indicated in this Section should also be complied with, as applicable.
4.2.1 The minimum web thickness of primary shell members in the lower hulls of column-stabilised units is to be not less than 0,017, where is spacing of stiffeners on member web, or depth of unstiffened web, in mm.