UIC 564-2: Fire Protection Regulations for Passenger Railway Vehicles and Test Methods Explained

On 11 November 2000, a Kaprun train fire in Austria killed 155 people as they were trapped in a burning funicular railway carriage. The fire started from a faulty electric heater located in the driver‘s cab at the lower end of the train and, within minutes, spread into the passenger compartment. The synthetic materials used for seat cushions, interior panelling and floor coverings released dense, toxic smoke that filled the carriage within three minutes. Many passengers never even had the chance to move towards the emergency exits. The tragedy became a turning point for railway fire safety worldwide. Post‑incident investigations revealed the fundamental weakness of relying on tests for ‘non‑flammability’ alone: many materials considered ‘low‑ignitable’ under older test methods were still producing lethal smoke and toxic gases in a real fire. (Source: Austrian Federal Ministry of Transport, Innovation and Technology; Final Report GZ 85.000/001‑II/‑30/2001)

The Kaprun disaster, and other catastrophic fires like it across Europe and Asia, demonstrated that railway fire safety could no longer be left to fragmented national rules or a simplistic ‘non‑flammable’ requirement. UIC Leaflet 564‑2 — Chapter 5, Rolling Stock — Regulations relating to fire protection and firefighting measures in passenger carrying railway vehicles or assimilated vehicles used on international services was the response. First published in 1991 and now in its 5th edition (September 2017), the 108‑page specification defines a comprehensive framework for material selection, component testing, fire detection, emergency equipment and crew training. Unlike earlier requirements that focused almost exclusively on preventing ignition, UIC 564‑2 introduced a performance‑based approach covering fire propagation, smoke density, toxicity and firefighting capability, making it the reference standard for international passenger fleets for over three decades. (Source: Normadoc; Demiryolu.net; CASfiretec)

What Is UIC Leaflet 564‑2?

UIC 564‑2 is a technical specification developed by the International Union of Railways (UIC) under Chapter 5 (Rolling Stock). The 5th edition, effective from September 2017, is the current version. The leaflet is available in English, German and French. (Source: Normadoc; DIN)

The leaflet applies to all passenger‑carrying railway vehicles — including carriages, multiple units (DMUs and EMUs), sleeping and couchette cars, driving trailers, and any vehicle of passenger coach construction — intended for international service. It does not apply to locomotives without passenger accommodation, freight wagons, or driver‘s cabs alone (although specific provisions cover cab materials). The scope explicitly covers: (a) material selection and fire behaviour; (b) construction requirements to limit flame propagation; (c) fire detection and alarm systems; (d) portable fire extinguishing equipment; (e) emergency lighting (referencing UIC 555); (f) training of train crew in fire‑fighting. (Source: Demiryolu.net; ZJTCN)

UIC 564‑2 is part of a family of UIC fire protection leaflets, including UIC 642 (fire precautions for all rail vehicles) and UIC 617‑1/625‑1 (fire protection for electric and diesel traction units). It is also the historical foundation for the European EN 45545 series, which superseded it for new EU rolling stock in 2013 but which continues to reference UIC 564‑2 for legacy vehicles and as a source document. (Source: Normadoc; Intertek Inform)

What Are the Core Material Selection and Fire Behaviour Requirements?

The most demanding section of UIC 564‑2 concerns the materials used in passenger compartments. The leaflet requires that, wherever possible, all materials incorporated into the vehicle structure shall be of inherently non‑flammable or low‑flammability types. This applies explicitly to:

• Thermal and sound insulation materials — Must resist ignition and flame propagation without using asbestos, which is strictly prohibited.
• Interior panelling (walls and ceilings) — Must have documented fire resistance determined by test methods referenced in the leaflet‘s appendices.
• Upholstery and seat cushions — Cushions made of combustible materials must be protected by non‑flammable covers. The textile materials themselves are subject to flame spread testing.
• Floor coverings — Tested for flame spread and smoke emission in accordance with Appendix 12.
• Carpets in aisles and other areas — Must meet specific ignition and flame propagation limits.
• Curtains, blinds and bedding — Subject to vertical flame test requirements.
• Paints and varnishes applied inside and outside the vehicle — Must not significantly contribute to fire propagation.
• Rubber seals for doors and windows — Tested for flame resistance per Appendix 6.

All materials must comply with the current fire protection standards of the railway administration that owns the vehicle, and those standards must include defined assessment criteria. The toxicity of combustion gases must be kept as low as technically achievable, and materials that produce dense, vision‑obscuring smoke or highly toxic gases are to be avoided. (Source: ZJTCN; CASfiretec)

The table below summarises the core material application categories and associated test appendices as defined in UIC 564‑2.

(Source: CASfiretec; UIC 564‑2 Appendices 3‑15; Baijian Test)

What Are the Fire Extinguishing Equipment and Emergency Requirements?

Beyond passive fire protection (limiting ignition and flame spread), UIC 564‑2 mandates active firefighting equipment and emergency procedures. These requirements are designed to give train crews and passengers the means to extinguish a fire in its early stages and to evacuate safely if suppression is not possible. (Source: ZJTCN)

Portable fire extinguishers: The leaflet requires that each passenger coach be equipped with a total extinguishing capacity of at least 6 kg. These extinguishers must be:

• Painted red (for immediate recognition).
• Not locked in cabinets (immediate access without tools).
• Placed in visible and easily accessible positions, sufficiently far from likely fire sources to be usable during an emergency.
• Protected from excessive heat while stored, but certified to remain effective at –20 °C to ensure winter service capability.
• Of types appropriate to the vehicle‘s construction materials and potential fire classes (e.g., powder or CO₂ for electrical fires, foam for combustible solids).

Vehicles equipped with oil‑fired heaters or appliances for cooking or electrical generation must also have an additional portable extinguisher dedicated to those appliances, as required by the national railway authority. (Source: ZJTCN)

Emergency lighting: Although the primary requirements for emergency lighting are defined in UIC 555, UIC 564‑2 explicitly references and mandates that emergency lighting must be provided to ensure safe evacuation in the event of primary power failure during a fire. The emergency lighting system must activate automatically when normal supply fails and provide sufficient illuminance for passengers to locate exits without panic. (Source: Demiryolu.net; UIC 555)

Electrical installations: Wiring must be installed in accordance with the national standards of each railway authority. Where cables pass through walls or bulkheads, they must be protected by metal conduits wherever possible, reducing the risk of fire spreading through cable‑penetration openings. (Source: ZJTCN)

Liquefied gas installations: Vehicles using liquefied petroleum gas (LPG) for cooking or heating must comply with mandatory requirements set out in Appendix 1 (Technical and safety regulations for LPG installations) and Appendix 2 (operating instructions for LPG appliances). These appendices cover cylinder storage, piping, ventilation, leak detection and shutdown procedures.

Crew training: The leaflet makes clear that the effectiveness of fire protection measures depends critically on the training of train crew. All crew members must be familiar with the location and operation of extinguishers and with emergency procedures. Fire drills and periodic refresher training are required. (Source: ZJTCN)

What Are the Mandatory Fire Test Methods in UIC 564‑2?

UIC 564‑2 does not merely specify “fire‑resistant materials”; it defines a comprehensive suite of test methods that must be applied to verify compliance. The leaflet‘s Appendices 3 through 15 provide detailed test procedures for specific material types and components. These test methods are recognised internationally and have been adopted as the basis for many national standards and for the EN 45545 series. (Source: CASfiretec; Baijian Test)

The table below summarises the key test methods defined in the UIC 564‑2 appendices.

(Source: CASfiretec; Baijian Test; fire‑testing.com)Comparison Table: UIC 564‑2 vs. EN 45545‑1 & ‑2EN 45545 is the European standard series for fire protection on railway vehicles. Since 2013, it has been the harmonised standard under the Technical Specifications for Interoperability (TSI) and has superseded UIC 564‑2 for new rolling stock placed on the EU market. However, the two standards differ significantly in their structure, risk assessment approach and test requirements. Understanding these differences is essential for engineers specifying fire protection for cross‑border or legacy vehicles. (Source: fire‑testing.com; Giordano; Intertek Inform)(Source: fire‑testing.com; Giordano; DKXF; Intertek Inform)

✍️ Editor’s Analysis

UIC 564‑2 was a groundbreaking document at the time of its first publication: it unified fragmented national fire safety rules, introduced a material‑by‑material test matrix, and moved beyond the simplistic concept of ‘non‑flammability’ to include flame spread, smoke opacity and toxicity. For nearly three decades, it was the gold standard for international passenger rolling stock. However, the leaflet now stands at a crossroads. It has been superseded in Europe by the more rigorous EN 45545 series, but it remains the primary reference for much of the world. Three critical gaps define its present and future.

The most significant deficiency is the lack of quantitative smoke toxicity limits. UIC 564‑2 states only that “the toxicity of combustion gases should be kept as low as possible” — a qualitative, unenforceable requirement. After the Kaprun disaster, it became tragically clear that many ‘low‑flammability’ materials release lethal hydrogen cyanide, carbon monoxide and hydrogen chloride when burning. EN 45545‑2 specifies exact limits for the Conventional Index of Toxicity (CIT_al) for each Requirement Set (R) and Hazard Level (HL). A modernised UIC 564‑2 must adopt similar quantitative toxicity thresholds, either by directly referencing EN 45545‑2 or by developing its own numeric limits based on recent fire toxicology research.

The second challenge is the growing divergence between UIC 564‑2 and European TSI requirements. For new rolling stock placed into service in the EU, TSI LOC & PAS mandates compliance with EN 45545‑1 and EN 45545‑2. Vehicles certified only to UIC 564‑2 are not accepted. This creates a two‑tier compliance burden for manufacturers producing fleets for both EU and non‑EU markets. The UIC and CEN should work towards a convergence document — perhaps a joint IRS (International Railway Solution) that maps UIC 564‑2 material classes to EN 45545 Requirement Sets and Hazard Levels, allowing a single design to be certified under both frameworks without duplicate testing.

The final — and most urgent — gap is the test method obsolescence. Some fire tests referenced in UIC 564‑2, such as the Appendix 5 textile flame spread method and the Appendix 13 seat test with paper ignition source, are known to produce less repeatable results than the modern European standards EN 16989 and EN 16990. EN 16989 uses a 15 kW gas burner for seat tests, eliminating the variability of paper ignition; UIC 564‑2 Appendix 13 has no equivalent requirement. The industry should petition the UIC to adopt the EN test methods as normative references in the next edition of Leaflet 564‑2, retiring the outdated appendices.

Despite these gaps, UIC 564‑2 cannot be discarded. It remains the only unified fire safety standard recognised globally, and it is deeply embedded in procurement contracts, maintenance manuals and certification records for thousands of passenger coaches operating outside the European Union. The path forward is not abandonment, but modernisation: quantitative toxicity limits, alignment with EN 45545 hazard levels, and adoption of repeatable test methods. — Railway News Editorial

What are the specific requirements for portable fire extinguishers under UIC 564‑2?

UIC 564‑2 Clause 4.2 mandates a total fire extinguishing capacity of at least 6 kg per passenger coach. The extinguishers must be painted red, not locked in cabinets (immediate access without tools), placed in visible and easily accessible positions, and located sufficiently far from likely fire sources so that they remain usable during an emergency. They must be protected from excessive heat while stored but certified to remain effective at –20 °C to ensure winter service capability. For vehicles fitted with oil‑fired heaters or gas appliances for cooking or electrical generation, each such appliance must have a dedicated extinguisher in addition to the 6 kg minimum, as specified by the national railway authority. The extinguisher type (powder, CO₂, foam) must be selected according to the potential fire classes in the vehicle: powder or CO₂ for electrical fires; foam or powder for combustible solids. (Source: UIC 564‑2, Clause 4.2; ZJTCN)

How does UIC 564‑2 address the prohibition of asbestos and other hazardous materials?

UIC 564‑2 explicitly prohibits the use of asbestos‑containing materials in thermal and acoustic insulation throughout the vehicle. The leaflet states: “Avoid use of insulation materials containing asbestos is prohibited.” Additionally, materials that produce toxic combustion gases (e.g., halogenated polymers such as PVC in upholstery or cables) are discouraged, although the leaflet does not provide a numeric threshold for toxicity. The selection of interior materials must take into account not only flame resistance but also the density of smoke (Appendix 15) and toxicity as low as technically achievable. For electrical cables, Appendix 9 references fire‑resistant cable types that reduce smoke and halogen emissions, aligning with the principle of low‑toxicity design. However, engineers should be aware that a direct ban on all halogenated materials is not present; for EU projects, EN 45545‑2 provides stricter limits on halogen content (e.g., for Requirement Sets R15‑R17 for cables). (Source: UIC 564‑2; ZJTCN; EN 45545‑2:2020 Annex A)

What is the difference between Appendix 7 (oxygen index) and Appendix 8 (foam material test) in UIC 564‑2?

Appendix 7 measures the Limiting Oxygen Index (LOI) of a material — the minimum oxygen concentration (as a percentage) required to sustain combustion. A material with LOI ≥ 25 % is generally considered self‑extinguishing in normal air (21 % oxygen). The test follows ISO 4589‑2, exposing a small vertical specimen to an oxygen‑nitrogen mixture and observing whether the material continues to burn. This is a small‑scale screening test, not a full fire scenario simulation. Appendix 8, by contrast, is a larger‑scale test specifically for foam materials (seat cushions, upholstery padding, insulation foams). It measures flame spread rate across the surface, after‑flame time, melt dripping and mass loss. The foam sample (typically 150 mm × 200 mm × 50 mm) is exposed to a defined gas burner flame for a set period. While Appendix 7 provides a fundamental property of the material, Appendix 8 gives a more realistic assessment of how a thick foam component behaves in a fire. For seat cushions, both Appendix 7 (on the foam core) and Appendix 13 (full‑scale seat test) are required. (Source: UIC 564‑2 Appendices 7, 8, 13; CASfiretec)

Is UIC 564‑2 still acceptable for new rolling stock operating in Europe, or must I use EN 45545?

For new rolling stock placed on the European Union market and operated under the Interoperability Directive (EU) 2016/797, the Technical Specifications for Interoperability for Locomotives and Passenger Rolling Stock (TSI LOC & PAS, Regulation (EU) No 1302/2014) requires compliance with EN 45545‑1 and EN 45545‑2. These European standards are harmonised and provide a ‘presumption of conformity’ with the TSI. UIC 564‑2 is not a harmonised standard and does not confer a presumption of conformity. Therefore, for a new locomotive or passenger train placed into service in any EU member state, referencing UIC 564‑2 alone is not sufficient. However, for (a) legacy fleets built before the TSI came into force, (b) vehicles operating exclusively outside the EU (e.g., in CIS countries, Africa, Asia, or South America), or (c) vehicles operating on non‑interoperable networks, UIC 564‑2 remains the applicable standard. For cross‑border fleets that operate both inside and outside the EU, it is common practice to specify compliance with both standards — using EN 45545 for the European portion and UIC 564‑2 as an additional requirement for international services. (Source: TSI LOC & PAS 1302/2014, Annex F; fire‑testing.com)

What is the maximum permissible smoke density for interior materials under UIC 564‑2 Appendix 15?

UIC 564‑2 Appendix 15 does not provide a single numerical limit for all materials; instead, the acceptance criterion is defined by the specific railway authority for each vehicle type. The test method itself follows a 3 m³ closed chamber (similar to the NBS smoke chamber), with a light source and photodetector measuring light transmission through the smoke. A sample of the material (typically 75 mm × 75 mm) is exposed to a radiant heat flux of 25 kW/m², with or without a pilot flame. The measurement output is the specific optical density (D_s) or the percentage light obscuration at defined time intervals (e.g., D_s at 90 seconds, 240 seconds, and 480 seconds). In practice, many railways have adopted limits of D_s ≤ 100 at 90 seconds and D_s ≤ 200 at 240 seconds for seat cushions and wall panels, but these are not mandated by the leaflet itself. By contrast, EN 45545‑2 specifies clear numeric limits: for example, for Requirement Set R1 (seats — other than driver‘s seats), the smoke density D_s (4 min) must be ≤ 600 at HL1, ≤ 300 at HL2, and ≤ 150 at HL3. Engineers should confirm the applicable limits with the ordering railway or national safety authority before designing a material to Appendix 15. (Source: UIC 564‑2 Appendix 15; EN 45545‑2:2020, Table 1; ISO 5659‑2)