Criteria Pollutants

The Clean Air Act, last amended in 1990, requires the
Environmental Protection Agency (EPA) to set National Ambient Air
Quality Standards (NAAQS) for pollutants considered harmful to public health and the environment. The Clean Air Act established two types of standards for these major air pollutants: primary and secondary. Primary standards set limits to protect public health, including the health of "sensitive" populations such as asthmatics, children, and the elderly. Secondary standards set limits to protect public welfare, including protection against decreased visibility, damage to animals, crops, vegetation, and buildings.

The EPA Office of Air Quality Planning and Standards (OAQPS) established NAAQS for six criteria pollutants:

• Ground Level Ozone
• Carbon Monoxide
• Lead
• Nitrogen Dioxide
• Particulate Matter
• Sulfur Dioxide

The Dallas-Fort Worth Region is in attainment for all criteria pollutants, with the exception of ground level ozone.  To learn more about ozone in the DFW nonattainment region, visit the links below.

• Current Ozone Activity
• Ozone Information

Monitoring Stations
The Texas Commission on Environmental Quality regulates monitors throughout the region to measure and analyze these pollutants. These Continuous Ambient Monitoring Stations (CAMS) measure various types of pollutants and weather parameters. To learn more, visit TCEQ's Air Monitoring Sites web page.

Additional Information:

• National Ambient Air Quality Standards Table
• Plain English Guide to The Clean Air Act