When railway vehicles are designed and constructed, the safety of passengers and staff is of the highest priority. The level of safety has been increased successively over the past

years and today all materials used must fulfil the highest fire protection requirements. The introduction of EN 45545-2 (Railway applications – Fire protection on railway vehicles Part 2: Requirements for fire behaviour of materials and components) sees the legislation being further tightened and standardised throughout Europe.

Armaflex Rail SD, manufactured by flexible technical insulation market leader Armacell, is the first closed-cell insulation material to offer greater fire safety for railway passenger vehicles. The product, which is the first to meet the Hazard Level 2 classification according to EN 45545, was officially launched in the UK at the recent Railtex exhibition.

Using Armaflex Rail SD on refrigerant pipework and air-ducts makes an important contribution to the high level of fire safety required in rail vehicles. The closed-cell insulation material with anti-microbial Microban® technology protects pipes against energy losses and condensation, and because it is so flexible, the material is extremely fast and easy to install.

Integrated protection

Armaflex Rail SD is the first flexible closed-cell insulation material with integrated fire protection for the rail vehicle construction industry. The completely new synthetic rubber achieves HL 2 according to EN 45545-2, a hazard level previously unattained by flexible insulation materials.

The highly flexible elastomeric foam has very good fire properties and extremely low smoke density, achieving an excellent Euroclass Bs1 D0 rating for insulation tubes. The smoke development of Armaflex Rail SD is 10 times lower than that of a standard elastomeric insulation product and the material is self-extinguishing, does not propagate fire or produce burning droplets.

Because it is a closed-cell insulation material with low thermal conductivity and high resistance to water vapour diffusion, Armaflex Rail SD provides installations with reliable long-term protection against energy losses and condensation.

As is the case with all Armaflex products, Armaflex Rail SD has a ‘built-in’ vapour barrier.

Armaflex Rail tubes [online]

Unlike traditional insulation materials, which need to be protected against moisture penetration by a separate vapour barrier, the resistance to water vapour diffusion is built up throughout the entire insulation thickness. This means increased reliability (the diffusion barriers of open-cell insulation materials usually consist of aluminium foils which can be easily damaged) but also leads to a substantial reduction in installation costs.

The Microban® technology offers additional protection against harmful microbes such as bacteria, mould and mildew. The antimicrobial additives are built into the insulation material during the manufacturing process and therefore do not wash or wear off.

Ease of installation

Armaflex Rail SD is available in different insulation thicknesses for a complete range of tubes, sheets, self-adhesive sheets and tape. A great advantage of the synthetic rubber, which becomes particularly apparent in the tight installation situations involved in rail vehicle construction, is the highly flexible nature of the material. The homogenous, three-dimensionally linked structure of elastomeric insulation allows the sheets to be cut neatly without the release of dust or fibre particles, which could pose a health threat if breathed in.

The high flexibility of the material also allows simple installation even on complex-shaped HVAC fittings and equipment. Application times can be further reduced by using self-adhesive sheets.