【 Weak current College 】 what is combustible gas explosion limits? ---Power By 【 China power house network 】

Combustible gas (vapor) and air mixture, and not at any concentration, experiencing the explosion fire can, and must be in a certain concentration range yuhuoyuan to explode. This could be an explosion of yuhuoyuan gas concentration range, known as gas explosion limits (including lower explosion limit and explosive limit). Different gas (vapor) explosion limits are different, such as hydrogen explosion limits are 4.0% ~ 75.6% (volume concentration), meaning that if the hydrogen gas in the air volume concentration in 4.0% ~ 75.6 per cent, yuhuoyuan would explode, but when the hydrogen concentration less than 4.0 per cent or greater than 75.6%, even if the experience of fire, do not explode. Methane explosion limits are 5.0% ~ 15% means that the volume of methane concentration in the air at 5.0% ~ 15%, between yuhuoyuan explode, otherwise it will not explode.
　　
Combustible dust explosion limit concept and gas explosion limits are consistent.
　　
Explosion limits generally used gas (dust) in the air volume percentage (%), gas (dust) expressed as a percentage of weight (g/m * or mg/l).
　　
Explosive limit is a very important concept, fire and explosion work has great practical significance:
　　
(1) it can be used to assess the combustible gas (vapor or dust) the size of the danger of explosion, as combustible gas classification and determine their fire risk category. In the lower explosion limit is less than a 10 per cent of combustible gases classified as level of combustible gases, their fire risk as CPI.
　　
(2) it can be used as the basis for the design, such as determining the fire rating of the building, design house ventilation system, all you need to know the places of combustible gas (vapor or dust) of explosive limit values.
　　
(3) it can be used as the development of safety and production procedures. In the production, use and storage of combustible gases (vapour, dust), to avoid fire and explosion, should strictly be combustible gas (vapor or dust) in concentrations below the lower explosion limit control. In order to ensure that, in developing safety procedures, according to the flammable vapor (steam, dust) blasting hazards, and other physicochemical properties, take appropriate precautions, such as ventilation, replacement, inert gas dilution, detection alarm, etc.