Criteria Air Pollutants

 
These pollutants are particulate matter, photochemical oxidants (including ozone), carbon monoxide, sulfur oxides, nitrogen oxides, and lead. The EPA calls these pollutants "criteria" air pollutants because it sets NAAQS for them based on criteria, as specified in the Clean Air Act. The term "criteria" refers to the latest scientific information related to these pollutants' effects on health or welfare.
 
Learn how EPA sets, reviews and revises standards (primary standardsHelpprimary standardsNational ambient air quality standards designed to protect human health with an adequate margin for safety. and secondary standardsHelpsecondary standardsNational ambient air quality standards designed to protect welfare, including effects on soils, water, crops, vegetation, man-made (anthropogenic) materials, animals, wildlife, weather, visibility, and climate; damage to property; transportation hazards; economic values, and personal comfort and well-being.),  standardsNational ambient air quality standards designed to protect welfare, including effects on soils, water, crops, vegetation, man-made (anthropogenic) materials, animals, wildlife, weather, visibility, and climate; damage to property; transportation hazards; economic values, and personal comfort and well-being.determines whether areas meet the standards, and works with areas to attain and maintain the standards.