Overview
EN 15355:2019+A1:2023 (CEN) specifies requirements for distributor valves and distributor‑isolating devices used in railway braking systems. The standard covers graduable‑release distributor valves (direct‑release types are excluded) and applies whether the isolating device is integral or separate. It defines requirements for design, type testing and quality assurance for components intended for vehicles up to 31 m length and brake‑pipe volumes up to 25 L (considering brake‑pipe inner diameters 25–32 mm). This edition supersedes EN 15355:2019 and includes Amendment A1 (approved Dec 2022 / published May 2023).
Key topics and technical requirements
The standard addresses functional, environmental and safety aspects relevant to distributor valves and isolating devices, including:
- Functional requirements: behavior as an inverse function of brake‑pipe input pressure; graduable release operation; treatment of relay valves (functionally regarded as none even if physically integral).
- Design and structural integrity: mechanical strength and sealing under maximum pressure conditions.
- Performance and type tests: tightness, inexhaustibility, sensitivity/insensitivity, compensation of output pressure, build‑up and release times, maximum output pressure behavior, quick‑service and inshot functions, manual release, and distribution/isolation functions.
- Environmental and durability tests: shock and vibration, temperature ranges, humidity, altitude, service life and compressed air quality per referenced standards.
- Test benches and procedures: defined bench types for single vehicles and trains (various lengths) to validate propagation, release times and charging behavior.
- Safety, marking and in‑service assessment: requirements for identification, designation, quality assurance and ongoing assessment.
- Related safety topics: fire behaviour of materials (EN 45545-2) and compatibility with braking system vocabulary and relay valve standards.
Applications and users
EN 15355:2019+A1:2023 is essential for stakeholders involved in railway braking components and systems, including:
- Manufacturers and suppliers of distributor valves and isolating devices
- Rail vehicle designers and system integrators specifying brake subsystem components
- Test laboratories and certification bodies conducting type and environmental testing
- Maintenance and quality assurance teams responsible for in‑service assessment and component marking
- Procurement and regulatory authorities referencing CEN standards in tenders and compliance
Keywords: EN 15355:2019+A1:2023, distributor valves, distributor‑isolating devices, railway braking standards, brake system components, CEN.
Related standards
Normative and referenced documents include (but are not limited to): EN 14198, EN 14478, EN 15611, EN 45545‑2, EN 61373, and ISO 8573‑1 - all relevant for brake systems, environmental testing and compressed air quality.