Radon zones in Pennsylvania
Last updated
EPA’s Map of Radon Zones places 67 Pennsylvania counties in its three radon potential zones: 49 in Zone 1 (highest), 17 in Zone 2 (moderate), and 1 in Zone 3 (low).
What this means for Pennsylvania homes
Most Pennsylvania counties fall in Zone 1. EPA predicts average indoor screening levels above 4 pCi/L across much of Pennsylvania, so elevated radon is common. Testing is especially worthwhile here, and radon-resistant construction features make sense for new homes.
EPA’s guidance is the same everywhere: test your home, fix it if the level is 4 pCi/L or higher, and consider fixing between 2 and 4 pCi/L. The zone map is from 1993 and should not be used to decide whether a single home needs testing.
Pennsylvania radon program
EPA lists the following state contact for Pennsylvania: PA Dept. of Environmental Protection, Bureau of Radiation Protection, phone 717-783-3594. Website: www.dep.pa.gov/Business/RadiationProtection/RadonDivision/Pages/Radon-in-the-home.aspx. State programs can tell you about local testing data, free or discounted test kits, disclosure rules for home sales, and credentialed radon professionals.
Pennsylvania counties and their EPA radon zones
| County | EPA radon zone |
|---|---|
| Adams County | Zone 1 |
| Allegheny County | Zone 1 |
| Armstrong County | Zone 1 |
| Beaver County | Zone 1 |
| Bedford County | Zone 1 |
| Berks County | Zone 1 |
| Blair County | Zone 1 |
| Bradford County | Zone 1 |
| Bucks County | Zone 1 |
| Butler County | Zone 1 |
| Cambria County | Zone 2 |
| Cameron County | Zone 1 |
| Carbon County | Zone 1 |
| Centre County | Zone 1 |
| Chester County | Zone 1 |
| Clarion County | Zone 1 |
| Clearfield County | Zone 1 |
| Clinton County | Zone 1 |
| Columbia County | Zone 1 |
| Crawford County | Zone 2 |
| Cumberland County | Zone 1 |
| Dauphin County | Zone 1 |
| Delaware County | Zone 1 |
| Elk County | Zone 2 |
| Erie County | Zone 2 |
| Fayette County | Zone 2 |
| Forest County | Zone 2 |
| Franklin County | Zone 1 |
| Fulton County | Zone 1 |
| Greene County | Zone 2 |
| Huntingdon County | Zone 1 |
| Indiana County | Zone 1 |
| Jefferson County | Zone 2 |
| Juniata County | Zone 1 |
| Lackawanna County | Zone 1 |
| Lancaster County | Zone 1 |
| Lawrence County | Zone 2 |
| Lebanon County | Zone 1 |
| Lehigh County | Zone 1 |
| Luzerne County | Zone 1 |
| Lycoming County | Zone 1 |
| McKean County | Zone 2 |
| Mercer County | Zone 2 |
| Mifflin County | Zone 1 |
| Monroe County | Zone 1 |
| Montgomery County | Zone 1 |
| Montour County | Zone 1 |
| Northampton County | Zone 1 |
| Northumberland County | Zone 1 |
| Perry County | Zone 1 |
| Philadelphia County | Zone 3 |
| Pike County | Zone 2 |
| Potter County | Zone 2 |
| Schuylkill County | Zone 1 |
| Snyder County | Zone 1 |
| Somerset County | Zone 2 |
| Sullivan County | Zone 1 |
| Susquehanna County | Zone 1 |
| Tioga County | Zone 1 |
| Union County | Zone 1 |
| Venango County | Zone 1 |
| Warren County | Zone 2 |
| Washington County | Zone 2 |
| Wayne County | Zone 2 |
| Westmoreland County | Zone 1 |
| Wyoming County | Zone 1 |
| York County | Zone 1 |
County names follow the 2020 Census. Zones from the EPA Map of Radon Zones (text version). Rows marked “zone of” use the zone EPA gave the predecessor or surrounding county.
Next steps: read how to test your home, check a result with the level calculator, or look up a single address by ZIP code.