Fire testing of rubber

All rubber materials are more or less combustible. The rubber materials which contain halogens such as chlorine, fluorine and bromine can be difficult to ignite and they are self-extinguishing.

In order to improve the fire resistance of a rubber material, substances which contain chlorine can be added, like for an example chlorparaffin. Antimony trioxide and aluminium hydarate with large amounts of crystal water are also used. Substances which contain chlorine are no longer recommended from an environmental point of view, which is why aluminium hydrate is now the most populary used additive. Aluminium hydrate works in the way that a lot of energy is required in order for the crystal water to be converted into vapour thus making the rubber difficult to ignite.

Rubber's fire resistance can be tested using vertical or horizontal methods. The most common method of testing rubber is to ignite a test strip at one end using a Bunsen burner and then observe the time of burning of the strip after the flame has been removed.

Elastocon offers equipment from TAURUS Instruments for determination of fire characteristics of rubber.