What are the National Ambient Air Quality Standards (NAAQS)?
Since the Clean Air Act’s (CAA) inception in 1970, EPA has set NAAQS for six common air pollutants: carbon monoxide (CO), lead (Pb), nitrogen dioxide (NO2), ozone (O3), particulate matter with aerodynamic size less than or equal to 10 micrometers (PM-10), and sulfur dioxide (SO2). For these common air pollutants there are two types of pollution limits referred to as the primary and secondary standard. The primary standard is based on health effects; and the secondary standard is based on environmental effects such as damage to property, plants, and visibility. The CAA requires these standards be set at levels that protect public health and welfare with an adequate margin of safety. These standards allow the American people to assess whether or not the air quality in their communities is healthful. Also, the NAAQS present state and local governments with the air quality levels they must meet to achieve clean air. To find out more in-depth information about the criteria air pollutants, v
