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The Air We Breathe

What is the Air Quality Index? What are the general health effects?

The Air Quality Index or AQI is a set of measures for 5 air pollutants.

Additional information can be found at the EPA's site, Air Quality Index-- a Guide to Air Quality and Your Health.


The image on the left is from the Pennsylvania Department of Environmental Protection. It shows the health statements for each of the AQI pollutants by AQI-- Good, Moderate, Unhealth for Sensitive Groups, Very Unhealthy, and Hazardous.

Air Quality Monitoring Stations can be found all around the country. You can map the monitoring stations for each AQI pollutant in your community.

AirData PA air quality monitoring stations mapAfter clicking on the link, enter a location to view a map of air monitor stations in that area.

Click a monitor location symbol on the map to view a pop-up with details about the monitor and to download concentration data.

Air Quality Index (AQI) today & tomorrow

Pennsylvania logo

View today's AQI and tomorrow's forecast from AIRNow for select Pennsylvania cities and counties
Altoona Erie Indiana County Johnstown
Lehigh Valley Liberty/Clairton area Mercer County Philadelphia
Pittsburgh Scranton/Wilkes-Barre State College Susquehanna Valley


Pennsylvania logo

Daily AQI data for PA regions from the PA Dept of Environmental Protection
Northwest PA Southwest PA Central PA Northeast PA Southeast PA

This site uses crowd sourcing to gather particulate matter data from sites around the world. After clicking on the link, enable the location finder, click on the map, or enter a state, city, or zip code in the search box in the upper left corner. You can view up to 7 days of data. To see more data, you will need to download the full data set.

Summary reports with historical data


Air Quality Index (AQI) historical data