Criteria air contaminants (CAC), or criteria pollutants, are a set of air pollutants that cause smog, acid rain and other health hazards. The laws and regulations of different polities may define different sets. CACs are typically emitted from many sources in industry, mining, transportation, electricity generation and agriculture. In most cases they are the products of the combustion of fossil fuels or industrial processes.
Contents |
Criteria air contaminants were the first set of pollutants recognized by the United States Environmental Protection Agency as needing standards on a national level. [1] The US National Ambient Air Quality Standards (NAAQS) requires the EPA to set standards on six CACs:[2]
The US regulates volatile organic compounds (VOCs), but not as CACs.
Canadian regulations include among CACs those species regulated by the US, plus volatile organic compounds (VOCs).[3]