Air Quality Data

The data gathered by the United States Environmental Protection Agency (EPA) on air quality with respect to carbon monoxide, a major air pollutant. The data includes information from more than 200 sites, identified by state, county, city, and local site names. An AQI value close to 0 signals "little to no" public health concern, while higher values are associated with increased risk to public health.

Think of the AQI as a yardstick that runs from 0 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 or below represents good air quality, while an AQI value over 300 represents hazardous air quality.

For each pollutant an AQI value of 100 generally corresponds to an ambient air concentration that equals the level of the short-term national ambient air quality standard for protection of public health. AQI values at or below 100 are generally thought of as satisfactory. When AQI values are above 100, air quality is unhealthy: at first for certain sensitive groups of people, then for everyone as AQI values get higher.