Criteria Pollutants

The Clean Air Act requires EPA to establish National Ambient Air Quality Standards (NAAQS) for six common air pollutants which are identified as “criteria air pollutants.”  The criteria pollutants are particulate matter (PM), carbon monoxide (CO), sulfur dioxide (SO2), Nitrogen dioxide (NO2), ozone, and lead (Pb).  

Additional information is provided in the following links:

Particulate Matter (PM10/PM2.5)