3.3 Each metal fastener shall be made of material which is inherently corrosion-resistant or treated to be corrosion-resistant.
3.3.1 Each ferrous metal part which is not stainless steel, shall be coated in accordance with ISO 1461.
3.3.2 Each stainless steel part shall be of a marine grade alloy having a corrosion resistance equal or better to grade 316.
3.3.3 Each aluminium part shall be of a marine grade containing not more than 0.06% copper.
3.3.4 Metals in contact with each other shall be galvanically compatible, or insulated to prevent galvanic corrosion in a marine environment.
3.4 Each mechanical fastening device securing a part of a ladder shall have a locking mechanism to prevent the device from loosening.
3.5 Each plastic material shall be of a type that retains at least 30 percent of its original tensile strength and at least 80 percent of its original impact strength when subjected to the one year outdoor weathering test described in ASTM D 1435.
3.6 Each part of a ladder shall be free of splinters, burrs, sharp edges, comers, projections, or other defects that could injure a person using the ladder.
3.7 Seizing, if used, shall consist of two- or three-ply marline of minimum breaking strength 800 N, or other suitable material of equivalent strength.
4 Construction
4.1 Each ladder shall have two side ropes on each side. Each step in the ladder shall be supported by each side rope.
4.2 The side ropes shall：
- be continuous from the top of the ladder to the bottom; and
- not be painted or otherwise coated or covered.
4.3 Unless a special arrangement is needed to secure the ladder to an accommodation ladder, powered pilot hoist, or other custom installation, the ends of the side ropes shall be finished as follows：
a) The top end of one or both of the side ropes on each side shall terminate just above the top step in a single eye splice or thimble large enough to accommodate at least two passes of side rope.
b) The top end of one side rope on each side of the ladder shall extend at least 3 m beyond the top ladder step or an extension service rope shall be fitted to each side rope eye splice or thimble by means of an eye splice or shackle, as shown in Figure 1. The diameter of an extension service rope shall be at least the diameter of the side ropes.
c) The side ropes shall not have fittings or form loops at the bottom of the ladder that can be used to attach additional ladder sections or tripping lines.
d) The ends of each side rope which do not terminate in a splice or fitting, shall be served or otherwise treated to prevent fraying.
