EN 45545-2 & EN 45545-3: Railway Fire Safety

Reaction to Fire & Fire Resistance

Railway vehicles use a wide variety of materials and components, including flooring, seats, cables, insulation, interior panels and fire barriers. Their behaviour during a fire is an important part of railway safety.

The EN 45545 series addresses different aspects of fire protection in railway vehicles. EN 45545-2 focuses on the fire behaviour of materials and products, while EN 45545-3 addresses the fire resistance of fire barriers.

Reaction to Fire – EN 45545-2

Reaction to fire describes how a material or product behaves when exposed to an ignition source or heat. Depending on the applicable requirement, testing may evaluate characteristics such as ignitability, flame spread, heat release, smoke production, smoke density and combustion-gas toxicity.

EN 45545-2 applies requirements according to the product, its intended application and the relevant railway hazard classification. The applicable testing pathway can broadly be understood as:

Product → Application → Requirement → Hazard Level → Required Tests

Typical railway products that may require fire-performance evaluation include:

• Flooring and floor coverings
• Seats and upholstery
• Interior panels
• Cables
• Insulation
• Plastics and polymeric materials
• Adhesives and other components

Typical Reaction-to-Fire Equipment

• Single Flame Source Apparatus – Used for applicable ignitability and flame-spread evaluations.
• Cone Calorimeter – Measures parameters such as heat release rate and total heat release under controlled heat exposure.
• Smoke Density Chamber – Evaluates smoke generation and optical smoke density under specified conditions.
• Gas Analysis / FTIR Systems – Used where applicable for analysing combustion gases.
• Radiant Panel Systems – Used for applicable evaluations of flame-spread characteristics, including certain flooring tests.

Fire Resistance – EN 45545-3

EN 45545-3 establishes the fire-resistance requirements and applicable test methods for fire barriers used in railway vehicles. Unlike reaction-to-fire testing, which examines material behaviour, fire-resistance testing evaluates the ability of a fire barrier or assembly to maintain its specified protective performance and provide the required level of protection during fire exposure.

Depending on the applicable requirement, evaluation can involve characteristics such as:

• Integrity – Ability to resist the passage of flames and hot gases.
• Insulation – Ability to limit heat transfer to the unexposed side.
• Structural Performance – Where applicable, ability to maintain required structural function during fire exposure.

Typical Fire-Resistance Equipment & Systems

• Fire Resistance Furnace – Exposes test specimens to controlled fire conditions and specified temperature profiles.
• Vertical Furnace Systems – Selected according to the orientation and type of fire barrier or construction.
• Load-Bearing Test Systems – Apply mechanical loads where structural fire-resistance performance needs to be evaluated.
• Temperature Measurement & Data Acquisition – Thermocouples and monitoring systems record temperatures and test data throughout the exposure.