How to define the degree of fire-resistant material
Determination of fire resistance is essential in building and industry. Under fire resistance ability understand designs and materials for a certain time without damage to withstand exposure to high temperatures. Not only to maintain, but in some cases and to limit the spread of fire, and maintain their required performance.
Instruction how to define the degree of fire-resistant material
All the building materials and construction for flammability are divided into three groups: non-flammable, nonflammable and sgoraemye.Nesgoraemye materials exposed to fire or high temperature non-flammable. It's all natural and artificial inorganic materials, gypsum boards, mineral plity.Trudnosgoraemymi called those materials when exposed to flame smolder, and after removal of the source of the fire smoldering stop. This asphalt concrete, gypsum concrete construction, timber, subjected to deep impregnation retardants.
It is obvious that flammable materials exposed to fire or high temperatures to ignite and continue to burn after removal of the source of fire. It's all organic materials: wood, peat, tar, felt, paper.
However, there are a number of building materials, visually non-open flame when ignited, but can harm the health food melting, releasing toxic gas.
Fire resistance occurs when any of the signs: the formation of cracks in the structure, the temperature rise on the unexposed surface, the loss of the bearing capacity of the construction or the complete combustion of the material.
Limits of fire resistance of materials or structures are defined by their fire tests. Standard fire reproduced in special furnaces lined with refractory bricks. A sample of the material or structure is installed in the furnace and remains there after the shutdown of the furnace until the temperature at all points of measurement starts to drop. Then, at the time that the sample design or construction material held in the furnace without damage, experts define the limits of fire resistance for the above opisaniyu.Poluchennye data is used in the construction of the choice of materials and designs.