Manufactured in compliance with JIS-F rules, the 1974 SOLAS conditions and the ISO recommended dimensions. Excerpt of Pilot Ladder Rules (SOLAS) 1. Side Ropes Ropes should be mold-resistant manila or heat-treated polyester rope with polypropylene core and should not be covered. Ropes shall be of a diameter which is no less than 18mm dia (57 mm in circumference), and have a breaking strength more than 24 kN. 2. Steps The distance of inner edge of side ropes should be more than 400mm. The width of step is no less than 115 mm, and thickness no less than 25 mm. The steps should be non-slip, hard wood steps without knot and equally spaced at 330±20mm. 3. The bottom 4 steps may be made of resilient synthetic raw material or rubber if it is of sufficient strength and stiffness. Rubber steps should be of the same required dimensions as the wooden steps. 4. Preventer Steps Preventer steps shall have the same specifications as normal steps, but the length of preventer steps shall not be less than 1.8 meter. Position of Preventer Steps correspond to the total number of Pilot Ladder steps. 5. Replacement Steps Repairs to pilot ladder shall be made to the steps and preventer steps only. The repaired steps and preventer steps shall have the form and dimensions specified in item (2) and (4), and not more than 2 such steps shall be used in any pilot ladder. Repaired steps and preventer steps shall be replaced by new ones as soon as possible. 6. Step Fixing Piece Step fixing piece must be made of wood or plastic. 7. Fastening Hardware Fastening hardware for rope and steps must be corrosion resistant, or made of similar material treated corrosion resistance.