Is Montgomery County, VA a radon risk area?

EPA's own radon map rates Montgomery County zone 1 - highest potential, predicting a county-wide average indoor level above 4 pCi/L. Montgomery County sits at the 94th percentile nationally for radon potential — above 94 of every 100 rated counties.

Montgomery County by the numbers

About 98,998 people live in Montgomery County, Virginia, spread over 386.848 square miles. Averaged across its land area, Montgomery County runs about 256 people per square mile. Rank 197 by population within its EPA zone puts Montgomery County at the 82nd percentile among zone peers. Geologically, Montgomery 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

Where the national indoor average runs about 1.3 pCi/L, Montgomery County's Zone 1 rating puts its predicted county average above EPA's 4 pCi/L action level itself. That doesn't mean every Montgomery County house tests high — a zone is a county-wide prediction, never a single-home reading — but it's a reason to test sooner rather than let it wait.

Testing and mitigation in Montgomery County

Nothing about Montgomery 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

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

The methodology guide shows exactly which EPA and Census sources feed Montgomery County's numbers. The guide to what a radon zone actually means covers why testing matters in every zone, not just Zone 1.