Is Shenandoah County, VA a radon risk area?
EPA places Shenandoah County in Zone 1 - Highest Potential — a predicted county-wide average indoor radon level above 4 pCi/L, based on the geology, soil and aerial radioactivity data behind EPA's national map. Nationally that's the 89th percentile for radon potential — Shenandoah County outranks 89% of every county EPA has rated.
How Shenandoah County compares
About 45,441 people live in Shenandoah County, Virginia, spread over 508.08 square miles. Averaged across its land area, Shenandoah County runs about 89 people per square mile. Rank 347 by population within its EPA zone puts Shenandoah County at the 67th percentile among zone peers. Shenandoah County falls in EPA Radon Region 3, one of 245 counties nationally EPA assigns to that same geologic province.
Zone vs. an actual test
Where the national indoor average runs about 1.3 pCi/L, Shenandoah County's Zone 1 rating puts its predicted county average above EPA's 4 pCi/L action level itself. Being in Zone 1 raises the odds Shenandoah 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.
Next steps for a home in Shenandoah County
Nothing about Shenandoah 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 Virginia's state radon program
Shenandoah County's test kit answers today; a Airthings radon monitor keeps answering for Shenandoah County over time. Affiliate link, RadonZoneCheck earns a commission there, at no extra cost to you. RADONZONE-10OFF at checkout knocks 10% off.
More on how this number was built
The methodology guide shows exactly which EPA and Census sources feed Shenandoah County's numbers. Whatever zone Shenandoah County carries, the zone explainer covers what it does and doesn't tell you about any one house.