BS MA 92:1981 download. Pilot ladders.
NOTE Users of BS MA 92 Marine Series should note that, while observing the requirements of BS MA 92, they should at the same time ensure compliance with such statutory requirements, rules and regulations as may be applicable to the individual ship concerned.
1 Scope and field of application
BS MA 92 specifies requirements for a ship’s pilot ladder which is provided for a pilot to embark and disembark safely.
2 References
ISO/R 887, Washers for hexagon bolts and nuts — Metric series.
ISO 1181, Three- or four-strand manila and sisal ropes.
ISO 1461, Metallic coatings I-lot dip galvanized coatings on fabricated ferrous products — Requirements.
ISO 2262, Rope thimbles.
ISO 2358, Prevailing torque-type steel hexagon locknuts — Dimensions — Metric series.
3 Dimensions
The dimensions of the assembled pilot ladder and of the components shall he in accordance with Figure 1 to Figure 6.
4 Materials
4.1 The materials of components shall be in accordance with Table 1. Metal parts shall not be used in the pilot ladder construction, except for items 5,9, 10 and 1
4.2 Steps, spreader steps, replacement step, replacement spreader step and split distance pieces shall each be made of hardwood (ash, oak, elm, beech or teak) free from knots, or from other materials having equivalent relative density, strength, durability and buoyancy. The lowest four steps may be made of rubber of sufficient strength and stiffness, or of other suitable material of equivalent characteristics. Steps and spreaders shall have an efficient non-slip surface.
4.3 The lashing for side ropes shall consist of two- or three-ply marline of minimum breaking strength 800 N, or other suitable material of equivalent strength.
5 Construction
5.1 The pilot ladder shall be assembled in accordance with Figure 1 and Table 2 to have an equal step spacing of 310 ± 5 mm.
5.2 Steps shall be constructed from one piece to the dimensions given in Figure 2. Their non-slip upper surfaces shall be provided by either
a) longitudinal grooving, or
b) the application of an approved non-slip coating.
5.3 Spreader steps shall be constructed from one main bar and two split distance pieces to the dimensions given in Figure 4, held firmly together by four M5 cup square bolts, washers and prevailing torque nuts. Metal parts shall be galvanized in accordance with ISO 1461. Spreaders shall be positioned in accordance with Table 2.
5.4 Side ropes shall have a diameter of 20 mm (circumference 64 mm) and shall be seized together as closely as possible above and below each step by a figure-of-eight racking seizing. The side ropes below the bottom step shall have a double racking seizing as shown in Figure 1. A racking seizing shall be applied below the rope thimbles. Side ropes shall each be of one continous length without joints.
5.5 A single 20 mm diameter (circumference 64 mm) manila extension service rope 3 000 mm in length (minimum) shall be fitted to each side rope thimble by means of an eye splice.
5.6 All rope ends shall he whipped for a distance of 25 mm with waxed sailmaker’s twine or equivalent material.
5.7 One spare replacement step shall he constructed from a single section to the dimensions given in Figure 5, and assembled with two split distance pieces as required in 5.3.
5.8 One spare replacement spreader shall be constructed from one top section to the dimensions given in Figure 6, and assembled with two split distance pieces as required in 5.3.
6 Designation
Pilot ladders conforming to BS MA 92 shall be designated by the following indications, in the order given:
— number of this International Standard:
— number of steps (Table 2).
Example: The designation for a pilot ladder consisting of 14 steps is:
Pilot ladder ISO 799 S14
NOTE The length of a pilot ladder determined by the designation shall include an allowance for a 15° adverse list.
Spare or additional components shall be designated by reference to the relevant International Standard.
Example: The designation for a spare step according to this International Standard is:
Step ISO 799
7 Marking
Pilot ladders conforming to BS MA 92 shall be permanently marked under the
two steps by the number of BS MA 92: ISO 799.