Traffic & Transportation

Understanding Air Quality

Local air quality affects how you live and breathe. Like the weather, it can change from day to day or even hour to hour.

How the AQI Works

Think of the AQI as a yardstick that runs from zero to 500. The higher the AQI value, the greater the level of air pollution and the greater the health concern. For example, an AQI value of 50 represents good air quality; an AQI value over 300 represents hazardous air quality.

An AQI value of 100 generally corresponds to the national air quality standard for the pollutant, which is the level EPA has set to protect public health. AQI values below 100 are satisfactory.

When AQI values are above 100, air quality is considered to be unhealthy - at first for certain sensitive groups of people, then for everyone as values get higher.

A key tool understanding outdoor air quality is the Air Quality Index, or AQI. The U.S. Environmental Protection Agency (EPA) and local officials use the AQI to provide simple information about local air quality, how it may affect you and how to protect your health.

What is the AQI?

The AQI is an index for reporting daily air quality. EPA calculates the AQI for five major air pollutants regulated by the Clean Air Act: ground-level ozone, particle pollution (also known as particulate matter), carbon monoxide, sulfur dioxide and nitrogen dioxide.

For each of these pollutants, EPA has established national air quality standards to protect public health. Ground-level ozone and airborne particles are the two pollutants that pose the greatest threat to human health in the United States.

Today's Air Quality

Office of Environmental Stewardship

Melissa Baker

Transportation Project Manager

M-F, 8 a.m. to 5 p.m.

City Hall

825 W. Irving Blvd.

Irving, TX 75060

P: (972) 721-484 6