Overview
ISO 19018:2020 - Ships and marine technology: Terms, abbreviations, graphical symbols and concepts on navigation standardizes the vocabulary, abbreviations, units and graphical symbols used for maritime navigation aboard ships. It covers special nautical units (nautical mile, cable, knot, degrees/minutes), directions and references (true, magnetic, compass, gyro north), course/heading/track terminology, bearings and corrections, effects of wind and current, position and waypoint conventions, time and astronomical navigation terms, depth/tides, terrestrial magnetism and GNSS concepts (including dilution of precision). Symbols for use in mathematical formulae are also provided, and the document harmonizes terminology with relevant IMO and IEC publications.
Key topics and standardized definitions
- Units and conversions: Nautical mile (1 NM = 1 852 m), cable (1/10 NM), knot as the unit of speed (nautical mile per hour) and angular units in degrees and minutes with guidance on notation.
- Reference directions: True, magnetic, compass and gyro north and the definition of “dead ahead.”
- Course, heading & track: Clear distinctions among course (CRS), heading (HDG), course over ground (COG), course through water (CTW), course made good (CMG) and related abbreviations.
- Speed terms: Speed through water (STW), speed over ground (SOG), speed of advance (SOA), etc.
- Bearings and corrections: Standardized terminology for bearing types and correction methods used in navigation.
- Environmental influences: Wind, current, leeway and drift triangle definitions to describe vessel motion and set/drift effects.
- Positioning and symbols: Geographic coordinates, fixes, tracks, waypoint navigation and a set of graphical symbols for charting and instruments.
- Time, celestial and GNSS: Universal time terms, celestial navigation concepts (sight reduction, celestial coordinates) and GNSS concepts including dilution of precision.
Practical applications and users
ISO 19018:2020 is used to harmonize communication, displays and documentation across the maritime sector. Primary users include:
- Ship bridge teams, navigators and training institutions (standardized terminology in procedures and logs)
- Hydrographic offices and chart makers (consistent symbols and units for charts)
- Marine electronics and ECDIS/Radar/AIS/GNSS manufacturers (uniform labels and symbols on displays)
- Maritime software developers and simulation providers (data models and UI consistency)
- Classification societies, flag administrations and operators (technical references for guidance and harmonization)
Related standards and harmonization
ISO 19018:2020 references and aligns terminology with IMO resolutions (e.g., MSC.191(79), MSC.192(79)), IEC navigation display standards (IEC 62288, IEC 62388) and chart specifications (Chart INT). It supersedes ISO 19018:2004 and reflects updates in GNSS and instrument terminology.
Keywords: ISO 19018:2020, maritime navigation, nautical mile, knot, course and heading, GNSS, waypoint navigation, graphical symbols, nautical terminology.
Открыть превью (PDF)Ships and marine technology — Terms, abbreviations, graphical symbols and concepts on navigation
