What EPA's radon map says about Isle of Wight County

Isle of Wight County is mapped as Zone 3 - Low Potential by EPA — meaning the county-wide average indoor level is predicted below 2 pCi/L. Rank it against the rest of the country and Isle of Wight County lands in the 20th percentile for radon potential.

Where Isle of Wight County sits nationally

About 40,942 people live in Isle of Wight County, Virginia, spread over 315.685 square miles. That works out to roughly 130 people per square mile. Among counties sharing Isle of Wight County's EPA zone, it outranks 61% of them by population. EPA's geology-based Region 3 groups Isle of Wight County with 244 other counties nationally sharing its underlying rock and soil profile.

What this actually means for a house in Isle of Wight County

At Zone 3, Isle of Wight County's predicted county average is under the national indoor average (~1.3 pCi/L) and well below EPA's 4 pCi/L action level — outdoor air nationally runs about 0.4 pCi/L for comparison. Low doesn't mean zero: EPA's own data shows homes in Zone 3 counties like Isle of Wight County testing above the action level often enough that skipping a test isn't the safe assumption.

If Isle of Wight County tests above the action level

Mitigation cost doesn't depend on Isle of Wight County's zone — it depends on the house's foundation. A typical system runs $800–$2,500 (about $1,200 typical), and testing first is what tells you whether that's needed at all.

Find Virginia's state radon program

Isle of Wight County's test kit answers today; a Airthings radon monitor keeps answering for Isle of Wight 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

Isle of Wight 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.