• by admin
• 2022-08-09

Fire rating of polyurethane sandwich panels

The fire rating of polyurethane sandwich panel is divided according to the national standard: B1, B2, B3. The highest fire rating of edge-sealed polyurethane sandwich panels is Class A. The national standard polyurethane sandwich panel does not have this fire rating, because the core material in the polyurethane sandwich panel is filled with core materials such as rock wool and glass wool. Customers of the core board self-define the fire rating as Class A. Therefore, customers in the market are commonly known as polyurethane edge-sealed rock wool (glass wool) sandwich panels as grade A.

Therefore, the fire rating of polyurethane sandwich panel can be divided into B1, B2, B3 and A grades (polyurethane edge-sealed rock wool (glass wool) sandwich panels commonly known by customers in the market). Next, we will talk about the fire rating of polyurethane sandwich panels in detail.

The fire rating of pure polyurethane sandwich panel is divided into three levels: B1, B2, and B3. Generally speaking, the fire rating of polyurethane sandwich panels of grade B1 is better, followed by B2, followed by B3. Next, let's learn about the difference between each fire rating.

1. B1 grade fireproof polyurethane sandwich panel - flame retardant building material

Flame retardant materials have better flame retardant effect. It is difficult to catch fire in the air or under the action of high temperature, and it is not easy to spread quickly, and the combustion stops immediately when the fire source is removed.

According to the national standard: a high oxygen index indicates that the material is not easy to burn, and a low oxygen index indicates that the material is easy to burn. It is generally considered that an oxygen index <22 is a flammable material, an oxygen index between 22 and 27 is a combustible material, and an oxygen index ≥ 27 is a flame-retardant material.

B1 grade fireproof polyurethane sandwich panel refers to the oxygen index ≥ 27. The direct way to test the fire rating of polyurethane sandwich panel is to ask the manufacturer for a monitoring report. The most direct way is to ignite it with a lighter, and the non-combustible phenomenon is obviously B1 fireproof.

2. B2 grade fireproof polyurethane sandwich panel - flammable building materials

Combustible materials have a certain flame retardant effect. It will not catch fire immediately when it encounters an open flame in the air or under the action of high temperature, but it will burn after a period of time, which may easily lead to the spread of the fire. B2 grade fireproof polyurethane sandwich panel refers to the oxygen index between 22 and 27. It can be seen that the B2 grade fireproof polyurethane sandwich panel is flammable but not easy to burn.

3. B3 grade fireproof polyurethane sandwich panel - flammable building materials

Without any flame retardant effect, it is easy to burn, and the fire danger is very high.

B3 grade fireproof polyurethane sandwich panel refers to the oxygen index <22, which can only be applied to customers without fire protection requirements.