Fire rating of rock wool board.

The fireproof grade of rock wool board is an important index to measure its fireproof performance.

According to the national standards, the fire protection grade of rock wool board is mainly divided into Grade A, B1, B2 and B3.

1. Grade A: Grade A rock wool board has fireproof performance, is almost nonflammable, and can effectively prevent the fire from spreading. In case of fire, the A-grade rock wool board can keep the structure intact for a long time, providing valuable time for personnel evacuation and fire fighting and rescue. The fire resistance limit of grade A rock wool board is generally about 1.5-3 hours, and some high-performance products can even reach 5 hours.

2. B1 grade: B1 grade rock wool board has good flame retardancy, which can prevent the fire from spreading to some extent. When encountering open fire or high temperature, B1 rock wool board is not easy to catch fire quickly, and it can stop burning quickly after the fire source is removed. However, its fireproof performance is slightly inferior to that of grade A rock wool board.

3. B2 grade: B2 grade rock wool board belongs to combustible building materials, which has certain flame retardancy but low grade. In case of fire, B2 rock wool board is easy to cause the fire to spread, especially in the wooden building environment. Therefore, when choosing rock wool board, we should try to avoid using B2 grade products.

4. B3 grade: B3 grade rock wool board belongs to flammable grade, and its flame retardant ability is almost zero. Its material is easy to burn, which can easily cause the fire to spread rapidly in a fire. Therefore, in the field of architecture, the application of B3 rock wool board is extremely rare.