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Rubber insulation material, as a widely used insulation material in the construction and industrial fields, has attracted much attention for its fire resistance performance. According to the national standard GB8624-2012, the fire rating of rubber insulation materials is mainly divided into Class A, B1, B2, and B3.

A-class (non combustible material): A-class materials have almost no or only slight combustion when exposed to a fire source, and do not produce flame spread, with extremely high fire resistance. This type of material is usually used in situations where high fire resistance is required.

B1 level (flame retardant material): B1 level materials are difficult to ignite and can quickly self extinguish even after ignition. The flame propagation speed is slow, the amount of smoke generated is low, and the toxicity is low. Suitable for interior decoration and insulation of most buildings.

B2 level (combustible material): B2 level materials are easy to ignite, but have a slower combustion rate, faster flame propagation, and higher smoke generation. Has certain flame retardant properties, but its fire resistance is not as good as B1 grade materials.

B3 level (flammable material): B3 level materials are highly flammable, with fast flame propagation, high smoke generation, and high toxicity. Poor fire resistance, usually not recommended for use in important building areas.

In addition, rubber insulation materials have a special fire rating - Class 0. Class 0 is internationally recognized as the highest grade and best fire resistance among rubber foam insulation materials. To achieve Class 0, the material must pass the two important fire performance testing requirements of BS476 Part 7 and BS476 Part 61989 in the UK.