Step 1: Select a health concern

You can generate reports based on specific health concerns or activity level. The default report provides information for the general population (with no specific health concern).

Asthma or other lung disease
Heart disease
Older adults and children (with no specific health concern)
Active Outdoors (with no specific health concern)
General Population (with no specific health concern)

Not sure which health concern to choose? Understand how health concerns affect the comparison.

Step 2: Select a location(s) from the map below

Use the map below to select up to 10 counties to compare. To begin, click on a state from the map (or list) to see a map of that state's counties. To select a county, click on the map or choose from the list of available counties. To compare counties from another state, choose "Select a Different State" near the upper right corner of the map.

Need help with the map?

On the state maps, counties without monitoring data appear gray. Note that some of these counties could be part of a nonattainment area, even though they lack monitoring data. For a list of nonattainment counties by pollutant, visit EPA's Greenbook. The red lines on the state maps indicate major highways.