Non-methane volatile organic compound

Non-methane volatile organic compounds (NMVOCs) are a large variety of chemically different compounds, such as benzene, ethanol, formaldehyde, cyclohexane, 1,1,1-trichloroethane or acetone.

Essentially, NMVOCs are identical to volatile organic compounds (VOCs), but with methane excluded. An important subset of NMVOCs are the non-methane hydrocarbons (NMHCs). Methane is excluded in air-pollution contexts because it is not harmful. Its low reactivity and thus long livetime in the atmosphere, however, makes it an important greenhouse gas.

Sometimes NMVOC is also used as a sum parameter for emissions, where all NMVOC emissions are added up per weight into one figure. In absence of more detailed data, this can be a very coarse parameter for pollution (e.g. for summer smog or indoor air pollution).

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