Fire safety requirements on rolling stock

Whether it is cables, seat upholstery, small attachments, or coatings – every installation material must comply with the applicable fire safety requirements for rolling stock. Extensive testing is therefore indispensable. These tests are designed to identify the hazards posed by materials and their constituents during combustion. Fire safety is assessed based on the extent to which the safety performance targets are achieved, as defined in the applicable standard for the specific type and area of use of the rolling stock.

The following international standards are of particular relevance in the field of materials testing:

• EN 45545-2
• British Standard (BS)
• NFPA 130 (ASTM E162 / E662)
• GOST

A material will only be considered suitable for assessment against the fire safety requirements applicable to rolling stock after successfully passing all individual tests. It is then classified for use based on its compliance with the relevant limit values, as defined in standard EN 45545-2. Materials that are inherently designed to meet the highest standards of fire performance are exempt from the testing requirement, as they are approved for use on rolling stock of any category. For example, components classified as A1 (non-combustible) under EN 13501-1.

Over 90% of our classified fire protection products comply with the HL3 standard requirements, making them approved for use on rolling stock of any design category. The table illustrates the assignment of hazard levels in relation to operation categories and design categories:

Our fire protection solutions are tested to EN 45545-2, taking into account the size of the exposed surface and their location of use on the rolling stock, in accordance with the requirements outlined in the table:

Fire protection testing in the railway sector is divided into two distinct categories or levels. On the one hand, tests are conducted at the material level: these tests focus on the composition, intrinsic properties, ingredients, and interactions of materials installed in trains.  On the other hand, there are global assessments. These assessments (prescribed by standards such as EN 45545-3 or NFPA 130) focus on the train’s structural components and its overall fire resistance performance. This approach considers the vehicle as an integrated whole and aims to ensure the safety of the structure  itself. Fire tests are conducted under conditions close to reality to evaluate the ability of materials and structures to effectively protect passengers and staff in case of fire. Unlike the material tests focused on hazard levels, this latter approach concentrates on fire resistance times required and provided by a material or structure.

Fire barriers are subject to various fire safety requirements for rolling stock, which depend on the operation category. A railway vehicle that passes through long tunnels and only allows lateral passenger evacuation in the event of a fire must meet more stringent fire safety requirements in terms of overall structural resistance than, for example, a tram.

Specially developed for use on rolling stock, our fire protection coating FLAMMADUR^® TE C has demonstrated impressive protective capabilities in fire resistance tests conducted to EN 45545-3 standards. To test the material and its fire protection properties under the most realistic conditions possible, we simulated a rolling stock floor structure using an extruded aluminium profile with a 18 mm thick plywood board installed on top. The fire-exposed side of the extruded aluminium profile – the side that would be subject to thermal attack in the event of a fire – was coated with FLAMMADUR^® TE C in a dry film thickness of 1200 µm. Thanks to the fast foam formation of the fire protection coating (intumescent or thermo-expanding effect), the aluminium profile and thus the entire floor structure were protected in a very short period of time. The fire safety requirements of class EI 45 in accordance with EN 45545-3 were fully met.

Fire barriers are subject to various fire safety requirements for rolling stock, which depend on the operation category. A railway vehicle that passes through long tunnels and only allows lateral passenger evacuation in the event of a fire must meet more stringent fire safety requirements in terms of overall structural resistance than, for example, a tram.