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Guide · Rail & Metro · Built in India
EN 45545-2 is the part of the European EN 45545 series that sets fire behaviour requirements for materials and components used on railway vehicles. It decides which reaction-to-fire tests apply to each product, such as flame spread, heat release, smoke density, smoke toxicity and oxygen index, and sets limits that get stricter as the vehicle's hazard level rises from HL1 to HL3.
The short answer
EN 45545 (Railway applications, Fire protection on railway vehicles) is published by CEN in seven parts: Part 1 general, Part 2 fire behaviour of materials and components, Part 3 fire barriers, Part 4 rolling stock design, Part 5 electrical equipment, Part 6 fire control and management systems, and Part 7 flammable liquid and gas installations. Part 2 is the materials testing part. The current edition is EN 45545-2:2020+A1:2023; the amendment added requirement sets R27 and R28, so the standard now defines 28 requirement sets (R1 to R28). In the EU, the rolling stock TSI (LOC&PAS) references EN 45545-2 for material fire requirements, and many rail projects outside Europe specify it too.
Why it matters
A fire on board must not start easily, spread quickly or give off dense or toxic smoke while passengers evacuate. So every combustible material in a vehicle has to be considered, including the enclosures, display covers, cables, seals and circuit boards inside onboard passenger information displays, CCTV cameras and recorders, and monitoring units. Rolling-stock tenders therefore often name EN 45545-2 alongside EN 50155 and EN 50121-3-2 and ask suppliers for fire test evidence for the materials in each unit. The vehicle builder or operator sets the hazard level; each supplier shows that its parts meet the requirement sets that apply at that level.
Key requirements
A summary of how the standard decides what to test and how hard. Always check the exact edition, hazard level and requirement sets named in your tender.
EN 45545-1 defines operation categories 1 to 4, based on factors such as tunnel running and how easily passengers can be evacuated, and design categories: N for standard vehicles, A for automatic trains with no emergency-trained staff on board, D for double-deck and S for sleeping and couchette cars. Together they give the hazard level, from HL1, the least demanding, to HL3, the most demanding.
The standard lists typical products, from interior panels and seats to cables, seals and electrotechnical equipment, and assigns each a requirement set. Each set names the tests and limit values per hazard level. For example, R1 covers interior surfaces and information displays, R15 and R16 cover interior and exterior cables, R24, R25 or R26 apply to printed circuit boards, and R26 covers small electrotechnical products.
Requirement sets combine tests such as ISO 5658-2 lateral flame spread, ISO 5660-1 cone calorimeter heat release (MARHE), EN ISO 5659-2 smoke density, EN 17084 smoke toxicity, EN ISO 4589-2 oxygen index and EN 60695 small-flame and glow-wire tests. Limits tighten from HL1 to HL3, so a material that is acceptable at HL1 may not be acceptable on an HL3 vehicle.
Products not in the list are assessed by location and exposed area: interior non-listed products larger than 0.2 m² follow R1 and smaller ones R22, with R7 and R23 for exterior. Small parts can be assessed with grouping rules, which add up the combustible mass of nearby components and apply no requirement, R24, or R22 (R23 outside) as the grouped mass grows. Test and classification reports should come from laboratories accredited to EN ISO/IEC 17025.
Related standards
EN 45545-2 covers how materials behave in a fire; it does not cover the electrical, environmental or EMC performance of onboard electronics. EN 50155 sets the overall requirements for rolling-stock electronic equipment and EN 50121-3-2 covers its electromagnetic compatibility, so the three are usually specified together for onboard units. For cabling, cables that meet EN 50306, EN 50264 or EN 50382 need no further testing against the cable requirement sets. Other parts of the series cover fire barriers (Part 3), vehicle design (Part 4) and electrical equipment design (Part 5). The edition, hazard level and requirement sets should be agreed between buyer and supplier at tender stage.
Checklist
Use these points when writing a specification or comparing suppliers. Ask for test and classification reports for the actual materials and components rather than relying on a datasheet statement.
Hazard level: which operation category and design category apply to the vehicle, and is the resulting hazard level (HL1, HL2 or HL3) stated in the tender?
Edition: does the evidence name the edition tested against, for example EN 45545-2:2020+A1:2023, and will the project accept reports to an older edition?
Material list: has the supplier listed every combustible material and component in the unit, such as enclosure, display cover, seals, cables and circuit boards, with the requirement set for each?
Test evidence: are there test or classification reports from an EN ISO/IEC 17025 accredited laboratory for each listed item, and are they recent enough for your project?
Cables: do the cables meet EN 50306, EN 50264 or EN 50382, or have they been tested against requirement set R15 or R16?
Grouping and small parts: where grouping rules are used, are the combustible mass, spacing and separation of small components documented?
Change control and sourcing: will the supplier keep material choices and fire evidence under change control for the life of the fleet, and does your programme favour Built in India / Make in India manufacturing?
Envision TechWorks
Envision TechWorks products are designed, manufactured and tested in an ISO 9001:2015 facility in India: production-ready and Built in India for Make in India programmes. PAPIS onboard passenger announcement and information hardware is built to EN 50155, and production includes in-circuit and functional test, AOI and X-ray inspection, and thermal cycling. Share the EN 45545-2 edition, hazard level and requirement sets named in your tender, and the team can discuss your requirements and build to your specification.
Related
The rolling-stock electronics standard that EN 45545-2 is often specified alongside, covering temperature, power supply, shock and vibration, EMC and testing.
Read the EN 50155 guide →Passenger announcement and information system for metro trainsets, with hardware built to EN 50155.
See PAPIS product details →Onboard and station IP surveillance with centralised video management and vandal-resistant cameras for rolling stock and stations.
See IP CCTV product details →The railway EMC series, with EN 50121-3-2 for apparatus on rolling stock: emission limits, immunity tests and performance criteria.
Read the EN 50121 guide →Platform and concourse displays that show route maps, arrivals, service status and emergency messages on sunlight-readable screens, managed centrally from the control room.
See Station PIS product details →How selecting IP CCTV for rolling stock differs from platforms, with a selection checklist for housings, operating envelopes and video management.
Read the IP CCTV guide →FAQ
EN 45545-2 is Part 2 of the European EN 45545 series on fire protection on railway vehicles. It sets the fire behaviour requirements for materials and components, defining which reaction-to-fire tests apply to each product and the limit values for hazard levels HL1 to HL3. The current edition is EN 45545-2:2020+A1:2023.
Hazard levels set how demanding the fire requirements are. They come from EN 45545-1, which combines the vehicle's operation category (1 to 4) with its design category (N standard, A automatic without emergency-trained staff, D double-deck, S sleeping and couchette). HL1 is the least demanding and HL3 the most; the vehicle builder or operator decides which applies.
It depends on each material and component. Examples include R1 for interior surfaces and information displays, R27 for light diffusers and display screen covers in the current edition, R15 and R16 for cables, R24, R25 or R26 for printed circuit boards, R26 for small electrotechnical products, and R22 or R23 for small non-listed products. Grouping rules can apply to small components mounted close together.
They cover different risks. EN 45545-2 covers the fire behaviour of materials, EN 50155 covers the overall design and testing of rolling-stock electronic equipment, and EN 50121-3-2 covers electromagnetic compatibility. Tenders for onboard electronics therefore often specify all three.
Envision TechWorks designs, manufactures and tests products in an ISO 9001:2015 facility in India. Share the EN 45545-2 edition, hazard level and requirement sets named in your tender, and the team can discuss your requirements and build to your specification, Built in India.
Share the EN 45545-2 edition, hazard level and requirement sets named in your tender, and the team will discuss how to build to your specification, Built in India.