Is Berks County, PA a radon risk area?

Berks County is mapped as Zone 1 - Highest Potential by EPA — meaning the county-wide average indoor level is predicted above 4 pCi/L. Berks County sits at the 98th percentile nationally for radon potential — above 98 of every 100 rated counties.

How Berks County compares

About 439,117 people live in Berks County, Pennsylvania, spread over 856.404 square miles. Population density there runs about 513 people per square mile. Rank 50 by population within its EPA zone puts Berks County at the 95th percentile among zone peers. Geologically, Berks County is grouped into EPA Region 3 alongside 244 other counties that share its rock and soil setting.

What this actually means for a house in Berks County

Berks County carries a Zone 1 label because its predicted average clears 4 pCi/L outright — three-plus times the 0.4 pCi/L typical outdoors and above the 1.3 pCi/L most homes see. Being in Zone 1 raises the odds Berks County homes test above the action level, but it does not mean any specific house does — EPA recommends every home be tested, in every zone, because the only way to know is to test.

Testing and mitigation in Berks County

Nothing about Berks County's EPA zone changes the mitigation number: $800–$2,500 nationally (around $1,200 typical), set by the house's foundation rather than the county it sits in — and only relevant once a test actually clears 4 pCi/L.

Find Pennsylvania's state radon program

Berks County's test kit answers today; a Airthings radon monitor keeps answering for Berks County over time. Affiliate link, RadonZoneCheck earns a commission there, at no extra cost to you. Use code RADONZONE-10OFF at checkout for 10% off.

More on how this number was built

Berks County's zone, rank and region all trace back to named EPA and Census sources — the methodology guide lists exactly which ones. If you're unsure why a low zone still deserves a test, the zone explainer covers that directly.