ISO 25862:2019

Overview

ISO 25862:2019 - "Ships and marine technology - Marine magnetic compasses, binnacles and azimuth reading devices" - specifies construction, performance and testing requirements for liquid-filled marine magnetic compasses, associated binnacles and azimuth reading devices used for ship navigation and steering. The standard covers compasses with a direct-reading system (reflecting, projecting or transmitting types) and defines two types of binnacles; the appropriate binnacle type is selected according to ship design (see Clause 5). It applies to Class A compasses (SOLAS-required standard compasses) and Class B compasses for lifeboats/rescue boats (IMO LSA Code), and excludes dry card compasses, hand-bearing compasses and devices using fundamentally different principles.

Key Topics and Technical Requirements

• Scope and applicability: liquid-filled, single-pivot directional systems supported inside a bowl; both gimballed and non-gimballed designs addressed.
• Construction and materials: magnetic materials, card position, top glass thickness (Class A), temperature and environmental conditions (Clauses 4 and 5).
• Directional system and dynamics: moment of inertia, suspension (Class A), magnetic moment, settling time, tilt and supporting forces.
• Compass card and readability: graduation intervals, card diameter and markings for Class A/B; visibility and lubber mark accuracy.
• Accuracy and errors: directional error, friction, swirl and induction errors, mounting errors for azimuth devices (Clause 4.6).
• Binnacle specifications: two binnacle types with requirements for correction provision, fore-and-aft marks, illumination and environmental tests (Clause 5).
• Azimuth reading devices: sights, vanes and level requirements (Clause 6).
• Testing, certification and installation: normative Annexes A–D cover testing/certification; Annexes E–G cover positioning on ship, determination of safe distances and deviation adjustment; Annex H gives lifeboat/rescue boat special requirements.

Practical Applications and Users

ISO 25862 is intended for:

• Marine equipment manufacturers (compass, binnacle and azimuth device designers)
• Shipbuilders and shipyards specifying navigation gear
• Classification societies and flag State surveyors for type approval and certification
• Lifeboat and rescue-boat equipment manufacturers (Class B requirements)
• Marine navigation officers and ship technical managers responsible for installation, adjustment and maintenance
• Maritime safety assessors and procurement teams seeking compliant navigation instruments

Using ISO 25862 helps ensure reliable heading information, reduced magnetic deviation risk, and regulatory compliance (SOLAS, IMO LSA).

Related Standards and References

• SOLAS Chapter V (navigation equipment requirements)
• IMO Lifesaving Appliances (LSA) Code (lifeboat compasses)
• ISO 1069 - Magnetic compasses and binnacles - Vocabulary
• Referenced bibliographic items in ISO 25862 (e.g., IMO Resolutions, EN standards)

Keywords: ISO 25862, marine magnetic compasses, binnacles, azimuth reading devices, Class A compass, Class B compass, SOLAS, lifeboats, compass testing, compass positioning, deviation adjustment.