Is Grayson County, VA a radon risk area?

EPA's own radon map rates Grayson County zone 2 - moderate potential, predicting a county-wide average indoor level between 2 and 4 pCi/L. That puts Grayson County in the 43rd percentile nationally for radon potential — higher than 43% of the counties EPA has rated.

How Grayson County compares

About 15,265 people live in Grayson County, Virginia, spread over 441.785 square miles. Population density there runs about 35 people per square mile. Rank 710 by population within its EPA zone puts Grayson County at the 31st percentile among zone peers. Geologically, Grayson County is grouped into EPA Region 3 alongside 244 other counties that share its rock and soil setting.

Why the zone isn't the answer by itself

Call it a middle case: above the 1.3 pCi/L most US homes average, below the 4 pCi/L line EPA uses to recommend mitigation — that's Grayson County's Zone 2 prediction. A Zone 2 rating is a moderate county-wide average, not a guarantee about any one house in Grayson County — testing is the only way to know an individual home's actual level.

If Grayson County tests above the action level

Nothing about Grayson 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

Grayson County's test kit answers today; a Airthings radon monitor keeps answering for Grayson 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

Every figure on this page traces to EPA's own Map of Radon Zones and Census data, documented in the methodology guide. If you're unsure why a low zone still deserves a test, the zone explainer covers that directly.