Overview
ISO 14819-2:2021 - part of the ISO 14819 series - defines the standardized Event and Information Codes used to encode traffic and travel messages for the Radio Data System Traffic Message Channel (RDS‑TMC) using the ALERT‑C protocol. This third‑edition document specifies the authoritative “Events List” (the meta‑language) and related coding conventions that enable compact, densely coded traffic messages to be broadcast over FM/RDS and decoded consistently by navigation terminals and in‑vehicle systems.
Key Topics
- Event List (database format): Canonical, language‑neutral CEN‑English phrase descriptions with decimal event codes used by RDS‑TMC operators. The list supports single‑phrase and combined‑phrase events to maximize channel efficiency.
- Event attributes: Each event entry includes fields for nature (information/forecast/silent), quantifier references, duration type (dynamic D or long L), default directionality, urgency, update class, and a phased‑out (P) indicator for deprecated codes.
- Quantifiers: Standardized quantifier types (examples: count, distance in metres, percent, speed km/h, duration minutes/hours, temperature °C, time‑of‑day, tonnes, metres, precipitation mm, frequency MHz) allow numeric parameters to be attached to phrases in a compact binary form.
- Phrase codes and categories: Phrase codes (A–Z) categorize messages (e.g., A: Level of Service, B: Incidents/Accidents, E: Roadworks, H: Weather, Q: Delays/Cancellations, Z: Supplementary Information). Terminals reconstruct human‑readable messages from stored phrase libraries.
- Message management: Update classes and duration semantics guide terminal presentation, persistence, and message prioritization.
- Annexes: Non‑metric and regional (GB‑English) variants of quantifiers, event lists, supplementary and forecast lists are provided.
Applications
- Encoding broadcast traffic alerts for FM/RDS using RDS‑TMC and ALERT‑C
- Traffic Message Channel (TMC) service providers creating compact broadcasts for navigation devices
- Navigation system and in‑vehicle terminal manufacturers implementing message decoding, presentation and localization
- ITS software developers integrating standardized event codes to ensure interoperability across countries and service providers
- Broadcasters and traffic authorities who need a consistent meta‑language for traffic and travel information
Who should use this standard
- ITS architects, RDS‑TMC service operators, and TMC content producers
- Navigation OEMs and aftermarket device manufacturers
- Road authorities, traffic management centers, and telematics service providers
- Software developers implementing ALERT‑C encoding/decoding and terminal message management
Related standards
- ISO 14819‑1: ALERT‑C coding protocol and message structure
- ISO 14819‑3: Position and place coding using ALERT‑C
- ISO 14819‑6: Optional message encryption (conditional access)
- IEC 62106: RDS specification (relevant for FM/RDS transport)
- DATEX Data Dictionary: terminology alignment referenced by ISO 14819‑2
Keywords: ISO 14819-2, RDS‑TMC, ALERT‑C, event codes, traffic message coding, intelligent transport systems, traffic and travel information.