Air Quality Index (AQI) is an index for reporting daily air quality. It tells you how clean or polluted your outdoor air is, and what associated health effects might be a concern for you. The AQI focuses on health effects you may experience within a few hours or days after breathing polluted air. 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. For Information regarding indoor air quality please visit the Indoor Web site.
The AIRNow Web siteThe U.S. EPA, NOAA, NPS, tribal, state, and local agencies developed the AIRNow Web site to provide the public with easy access to national air quality information. The Web site offers daily AQI forecasts as well as real-time AQI conditions for over 300 cities across the US, and provides links to more detailed State and local air quality
Air Quality Forecasts - Nationwide daily air quality forecasts provided
by State and local Air Agencies for over 300 major U.S. cities.
Air Quality Conditions - Nationwide and regional real-time ozone air
quality maps covering 46 US States and parts of Canada. These maps are updated daily every hour.