BS ISO 13713:2020 Ships and marine technology — Ship’s mooring and towing fittings — Mooring chocks.
1 Scope
This document specifies the types, nominal sizes, dimensions and materials, as well as construction,manufacturing and marking requirements, for mooring chocks installed to lead the mooring and
towing rope of a ship.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content constitutes requirements of this document. For dated references, only the edition cited applies. Forundated references, the latest edition of the referenced document (including any amendments) applies.
IMO Circular MSC/Circ.1175, Guidance on shipboard towing and mooring equipment
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
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safe working load
safe load limit (maximum permissible load) of the fittings used for mooring and towing
4 Classification
4.1 Type
The mooring chocks shall be classified by its installation site as belonging to one of the following types:
a) Type A: deck-mounted mooring chock;
b) Type B: bulwark-mounted mooring chock.
4.2 Nominal sizes
The nominal sizes, L × H, of mooring chocks are denoted by reference to the width and height of the opening of the chock, in millimetres. For the mooring chocks having the same size, the letter of the alphabet, i.e. A or B, is followed by the nominal size for the different safe working loads (SWL).BS ISO 13713 pdf download.