Is Chittenden County, VT a radon risk area?

Chittenden County is mapped as Zone 3 - Low Potential by EPA — meaning the county-wide average indoor level is predicted below 2 pCi/L. That puts Chittenden County in the 28th percentile nationally for radon potential — higher than 28% of the counties EPA has rated.

How Chittenden County compares

About 170,851 people live in Chittenden County, Vermont, spread over 536.87 square miles. Population density there runs about 318 people per square mile. Rank 153 by population within its EPA zone puts Chittenden County at the 85th percentile among zone peers. Chittenden County falls in EPA Radon Region 1, one of 59 counties nationally EPA assigns to that same geologic province.

What this actually means for a house in Chittenden County

Well clear of both the 1.3 pCi/L national indoor average and EPA's 4 pCi/L action level, Chittenden County's Zone 3 prediction is the low end of the scale. Low doesn't mean zero: EPA's own data shows homes in Zone 3 counties like Chittenden County testing above the action level often enough that skipping a test isn't the safe assumption.

Testing and mitigation in Chittenden County

Nothing about Chittenden 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 Vermont's state radon program

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

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.