ISO 25862:2019 specifies requirements for the construction and performance of marine magnetic compasses for navigation and steering purposes, binnacles and azimuth reading devices.

Two types of binnacle are specified; the appropriate type for a given vessel is determined by the design of the ship (see Clause 5).

This document applies to liquid-filled magnetic compasses:

— intended for use in ship's navigation and steering in sea navigation;

— having a direct reading system; and

— which can be of the reflecting, projecting or transmitting types.

In the context of this document, a magnetic compass is an instrument consisting of a directional system supported by a single pivot inside a bowl that is completely filled with liquid and supported by gimbals inside or outside the bowl. However, this document also addresses compasses without gimbals; the requirements relating to gimbals do not apply to such compasses.

This document applies to magnetic compasses carried on board:

a) all ships required to carry a standard compass as per SOLAS Chapter V, the Class A magnetic compass;

b) lifeboats and rescue boats as per the IMO Lifesaving Appliances (LSA) Code, fitted with the Class B magnetic compass; and

c) all ships to which a) and b) above do not apply, but which are fitted with a Class A or B magnetic compass.

This document does not apply to:

a) dry card compasses;

b) types of compass designed on principles different from those stated above or not complying with the descriptions given; or

c) hand bearing compasses.

The requirements for the testing and certification of marine magnetic compasses, azimuth reading devices and binnacles are given in Annexes A, B, C, and D. The requirements for the positioning in ships, the determination of safe distances and the deviation adjustment of compasses are given in Annexes E, F and G, respectively. The special requirements of the magnetic compass for lifeboats/rescue boats are given in Annex H.