The concept of atmospheric pollutant detection standards is explained in detail. With the rapid development of modern industry and the large-scale application of fossil fuels, people enjoy the beautiful life brought by social progress, and also see the problems of air pollution and ecological deterioration brought about by industrial development. With the problems that people live in, the disease increases, the quality of life declines, and people begin to reflect on the relationship between the environment and development.
The current environmental problems are mainly reflected in air pollution and water pollution. Air pollution is mainly manifested in complex types and compositions. For example, common pollutants include hydrocarbons, ketones, esters, aldehydes, and amines. According to the environmental impact assessment system classification, it is mainly divided into non-methane total hydrocarbons (NMHC), VOC, VOCs, TVOC, etc. The details are explained below.
1. Non-methane total hydrocarbon (NMHC) official website: http://
According to the "Air Pollutant Emission Standards" (GB16297-1996) and "Detailed Explanation of Air Pollutant Emission Standards", non-methane total hydrocarbons mainly include alkanes, olefins, aromatic hydrocarbons and oxygenated hydrocarbons, and actually refer to C2- Hydrocarbons of C12. "Gas Chromatography for Determination of Total Methane-Free Hydrocarbons in Fixed Source Exhaust Gases" (HJ/T38-1999) defines non-methane total hydrocarbons as "general term for hydrocarbons other than methane (mainly C2-C8)".
2, VOC
VOC generally refers to an organic compound that is easily volatilized at normal temperature. More common are benzene, toluene, xylene, ethylbenzene, styrene, formaldehyde, TVOC (6-16 carbon alkanes), ketones and the like. These compounds are highly volatile and lipophilic and are widely used in industries such as footwear, toys, paints and inks, adhesives, cosmetics, interior and automotive decorative materials.
3, VOCs
VOCs are the abbreviation of Volatile Organic Compounds. VOCs and VOCs are actually the same kind of substances. Because VOCs generally have more than one kind of components, VOCs are more precise. Http://
4, TVOC
TVOC (Total Volatile Organic Compounds) is the abbreviation of "Total Volatile Organic Compounds" in the Indoor Air Quality Standard (GB/T18883-2002). It mainly refers to "Using Tenax GC or Tenax TA sampling, non-polar columns. (Polarity index less than 3) was analyzed for retention of volatile organic compounds between n-hexane and n-hexadecane".
It can be seen from the definitions of non-methane total hydrocarbons (NMHC), TVOC, VOCs that non-methane total hydrocarbons mainly refer to hydrocarbons between C2-C12, TVOC mainly refers to volatile organic compounds between C6 and C16, VOCs The range is relatively wide and basically contains all volatile organic pollutants.
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