Flame retardant rubber
Rubber materials used in environments with fire risk must slow the spread of flame and reduce smoke generation. For this purpose, flame retardant (FR) rubber is produced.
How does flame retardant rubber work?
FR rubber is made by adding special additives (halogenated or halogen-free flame retardants, metal hydroxides) to the compound. Under heat these components form a flame-quenching gas or a protective char layer, thereby preventing combustion from continuing.
Key flammability standards
- UL 94 — burning behaviour of plastics and elastomers (V-0, V-1, V-2 classification)
- EN 45545 — fire safety for railway transport materials
- FMVSS 302 — automotive interior materials
- ISO 5658 / LOI (oxygen index) — measurement of ignition ease
Where is it used?
Flame retardant rubber is required in areas where safety is critical:
- Metro, train and bus cabin components
- Electrical cable transits and insulation seals
- Building ventilation and fire protection systems
- Mining and oil & gas equipment
Material selection
The FR property can be given to various elastomer bases. EPDM-, NBR- and chloroprene-based compounds are often formulated with FR additives. The correct compound composition ensures both the flammability class and mechanical durability — our article on rubber compounds is helpful on this topic.
Trade-offs to consider
Too many flame retardant additives can reduce the rubber's flexibility and mechanical strength. A balance must therefore be struck between the FR level and physical properties. The required operating temperature also determines material selection; for high temperatures, materials such as Viton FKM for high temperatures are considered.
NUR KAUÇUK capabilities
In the NUR KAUÇUK laboratory we prepare and test flame retardant compounds according to the customer's flammability class requirement. Our production process ensures the precise application of the formulation.
To choose flame retardant rubber solutions for your project, see the products section and contact us for technical advice.