Overview
ISO/TR 18155:2025 - Railway applications - Principles of train detection for operations and services provides non‑technical, operational guidance on train detection across any railway. It links train detection methods to the management of operational principles, describing how detection affects safety, efficiency and service quality. The Technical Report is intended to support decision‑making for new lines, upgrades or renewals of train detection systems - without prescribing technical specifications.
Key topics and requirements
The report focuses on high‑level principles rather than detailed technical design. Major topics include:
- Categorization of train detection methods
- Signal block detection (section detection, border detection, manual block)
- Single point detection (e.g., optical detection, treadles)
- Operational characteristics that influence choice, such as sectioning/block mode, train speed (including high‑speed operations), train density/headway, station layout, shunting and interface conditions.
- Environmental conditions that affect detectability: climate, geography (plateau/plain), maintainability, electromagnetic environment, vibration, pollution and extreme events.
- Impacts on operations
- Safety: position information used to grant movement authorities and prevent collisions/derailments.
- Efficiency and service: capacity management, timetable adherence, passenger information and freight tracking.
- Operation modes and management
- Principles for normal operation, degraded operation and management measures when detection functions fail.
- Guidance on combining multiple detection methods for redundancy.
- Selection principles and criteria for choosing suitable methods based on operational and environmental constraints, and practical application examples.
Practical applications - who uses this standard
ISO/TR 18155:2025 is aimed at non‑technical stakeholders and practitioners involved in railway operations and service planning:
- Railway operators and traffic control centres - for aligning detection approach with operational rules and contingency procedures.
- Infrastructure managers - for investment decisions on new lines, upgrades and maintenance strategies.
- Signalling planners, procurement teams and systems integrators - to evaluate the operational suitability of detection options.
- Maintenance planners and emergency managers - to define degraded‑mode procedures and maintainability requirements.
- Consultants and regulators - for policy, operational risk assessment and interoperability considerations.
Related standards
- The report references terminology and definitions from IEC/ISO resources (for example, IEC 62290‑1:2025 is cited for the definition of “train detection”). Users should consult relevant signalling and electrotechnical standards for the technical and safety requirements to implement detection systems.
Keywords: ISO/TR 18155:2025, train detection, railway operations, signal block detection, border detection, axle counter, single point detection, operational safety, degraded operation, railway signalling.