What is the EN45545-2 Standard for Rail Applications?
Since 2018, EN45545-2 has been the mandatory European fire safety standard for railway vehicles, specifying the behaviour of materials and components, including silicone gaskets, to ensure maximum passenger evacuation time in the event of a fire.
This framework for fire resistance and low smoke toxicity classifies materials based on operation categories and design configurations, assigning hazard levels from HL1 to HL3. This standard is in addition to other national standards such as BS6853 (the British standard) to create a unified safety protocol across European rail networks.
In order to comply with EN45545-2, manufacturers must rigorously test their materials to meet a range of demand criteria. Key areas evaluated include:
- Flame spread: Preventing the rapid spread of fire across surface areas.
- Heat release: Minimising the thermal energy contributed by burning materials.
- Smoke opacity: Ensuring visibility remains high enough for safe passenger evacuation.
- Toxic gas emission: Limiting the release of poisonous gases during combustion.
Why is EN45545-2 Compliance Critical for Silicone Gaskets?
Compliance is essential as non-compliant materials (such as general-purpose silicone gaskets) can allow the rapid spread of fire and emit highly toxic smoke, jeopardising passenger safety and resulting in severe legal repercussions.
High-performance silicone seals are used for a wide range of applications in modern rail design, including critical seals in HVAC systems, lighting enclosures, and exterior doors. Given their widespread use, any weakness in their fire resistance exponentially increases risks throughout the entire train carriage. This is why risk mitigation at the component level is essential for safety and success.
Using non-compliant materials also exposes rail manufacturers, suppliers and operators to massive liabilities. The table below compares the differences between compliant and non-compliant material choices.
| EN45545-2 Compliant Silicone Gaskets | Non-Compliant Gaskets | |
| Fire Resistance | Self-extinguishing and highly resistant to ignition. | Combustible, accelerating flame spread. |
| Smoke and Toxicity | Low smoke density and ultra-low toxic emissions. | Dense, opaque smoke with high toxicity. |
| Regulatory Status | Legally approved for European rail transit. | Subject to fines, impounding, and legal consequences. |
| Passenger Safety | Maximises evacuation time. | Rapidly compromises escape routes and air quality. |
How Do Hazard Levels (HL1-HL3) Dictate Silicone Gasket Selection?
Hazard levels dictate gasket material selection by matching the fire safety performance of the silicone compound to the train’s specific operating environment and design risk for the application. Higher-risk environments like underground networks and sleeping cars are classified as HL3 and require silicone gaskets with the highest flame resistance, lowest smoke opacity, and ultra-low toxicity.
A gasket approved for standard open-air surface routes (HL1) will fail compliance audits if installed on underground rolling stock requiring HL3 certification. It’s critical that engineering teams specify the correct hazard level during the initial design phase, preventing the need for costly redesigns.
Key factors that determine hazard level specification include:
- Operating infrastructure: Time spent in enclosed tunnels or underground networks.
- Vehicle type: Standard passenger carriages, compared to sleeping cars or double-decker carriages,
- Evacuation Capability: Estimated time required for passengers to reach a safe location during an emergency.
- Component Location: Internal carriage seals versus external body gaskets and seals.
Where Can Manufacturers Find EN45545-2 Compliant Rail Solutions?
Rail industry manufacturers can source fully EN45545-2 compliant materials and components, including high-performance silicone gaskets, through specialised rubber manufacturing partners who can provide documented testing credentials.
Sourcing materials and components from a leading rail industry supplier guarantees that every seal meets the strict regulatory and hazard level requirements for internal and external rail applications. Partnering with a trusted supplier streamlines the procurement process and provides peace of mind for rail engineers.
For compliant, high-performance materials from a company with extensive rail experience, explore CB Frost’s comprehensive rail industry services. Make sure your rail fleet is safe, fully compliant, and continuously operational.
