Definition of combustibles
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How are the combustibles, retardants and non-combustibles commonly mentioned in construction regulations and petrochemical regulations defined? Are there any relevant specifications? Where can I find information about the combustion properties of a substance? Please advise. Thank you!
The distinction between refractory and non-combustible materials is based on the oxygen index. Materials with an oxygen index of more than 25 are flame retardant ； Materials with an oxygen index of more than 35 are non-combustible.
Thanks! What are the 25 and 35 you mentioned based on? Where can I find the oxygen index? 2#sdqd800
The oxygen index refers to the minimum oxygen concentration required for flammable combustion of materials in an oxygen-nitrogen mixed gas flow under specified conditions. Expressed as the volume percentage of oxygen.
We generally judge the flammability of materials through the MSDS of materials. The MSDS of general materials has a description of flammability, which can be used to judge.
GBT 21846-2008 Determination of solid flammability of industrial chemical products contains test methods, but it only states that conditions are flammable and does not distinguish between flammable and refractory
Take a look at the following information, maybe you will find some answers: Building materials are divided into three types: "non-combustible materials", "quasi-non-combustible materials" and "flammable retardant materials". This distinction is not to investigate the "flammability" of building materials, but to investigate their "usefulness" and "safety". “"Usefulness" refers to whether the building material melts or breaks when the temperature rises to a certain level. ； “"Safety" refers to whether building materials produce substances harmful to the human body after burning. In the event of a fire, materials whose non-combustible properties last for more than 20 minutes are called "non-combustible materials"” ； 1. Concrete, bricks, tiles, mortar, stone, glass 2. Iron, aluminum, metal plates 3. Gypsum boards with a thickness of more than 12 mm, cement boards with a thickness of more than 5 mm containing glass fiber, etc. Materials whose non-combustible properties can last for more than 10 minutes are "quasi-non-combustible materials"” ； 1. Gypsum board with a thickness of more than 9mm, wood wool cement board with a thickness of more than 15mm, hard wood cement board with a thickness of more than 9mm, pulp cement board with a thickness of more than 6mm, etc. 2. Non-combustible materials Materials whose non-combustible properties can last for more than 5 minutes are "flammable retardant materials". 1. Flame-retardant plywood with a thickness of more than 5.5mm, gypsum board with a thickness of more than 7mm, etc. 2. Non-combustible materials 3. Quasi-non-combustible materials