News

Custom foams which meet smoke / fire protection standards in the rail transport industry

The key criteria of choice in selecting materials intended for use inside trains is its meeting of smoke / fire protection standards. In the case of foams, this compatibility depends on the chemical composition of the foam, the presence of additives and physical characteristics.

Smoke / fire protection standards in the rail transport industry

The materials used in the rail transport industry must meet the requirements of several different smoke / fire protection standards. Here are the standard principles used.

General standards

  • EN 45545-2: European Union standard on fire resistance testing of rail transport components
  • Standard NFPA 130: protection against fire and the safety of guideways in transit and passenger rail systems

Flame resistance

  • Standard ASTM E162: flammability of surfaces
  • Standard ASTM C1166: flame propagation
  • FAR 25.853: Federal standard for flammability

Release of smoke

  • Standard ASTM E1354: release rates of heat and visible smoke
  • Standard ASTM E662: optical density of smoke

Toxicity

  • Standard ASTM E662/BSS 7239: generation of toxic gases by materials upon combustion (the United States and the European Union).

What are the types of suitable foams?

The types of foams most commonly used in the rail transport industry for a variety of different applications as they meet smoke / fire protection standards.

  • Elastomeric rubber foams are used for phonic and thermal insulation;
  • Silicone foams are the materials most often used to meet the requirements of smoke / fire protection standards;
  • Vinyl nitrile foams have good flame resistance and impact resistance;
  • Polyurethane elastomer foams are well known for their anti-vibration and noise reduction as well as sealant properties;
  • PET foams are used for structural applications and they can also be used for thermal insulation;
  • Mass-loaded vinyl foams are used for soundproofing and to design sound barriers;
  • Melamine foams are used for cushioning and have anti-fire properties;

The foams used must also not include any toxic components

Over and above the chemical composition of the polymers used, to be compatible with smoke / fire protection standards, the foams must not contain toxic products likely to be released in the event of a fire:

  • Halogenated products, such as chlorine or bromine, are to be avoided. In fact although bromine is an element well known for its use as a flame retardant, it is also highly toxic;
  • Heavy metals, such as cadmium and lead, are prohibited;
  • Formaldehyde, a binder often used in plastics but that is a highly flammable and carcinogenic gas, is to be avoided.

 

Do not hesitate to contact an ADDEV Materials expert for help regarding your applications