Is Forsyth County, NC a radon risk area?

EPA places Forsyth County in Zone 2 - Moderate Potential — a predicted county-wide average indoor radon level between 2 and 4 pCi/L, based on the geology, soil and aerial radioactivity data behind EPA's national map. That puts Forsyth County in the 64th percentile nationally for radon potential — higher than 64% of the counties EPA has rated.

Forsyth County by the numbers

About 398,143 people live in Forsyth County, North Carolina, spread over 408.046 square miles. Averaged across its land area, Forsyth County runs about 976 people per square mile. Rank 64 by population within its EPA zone puts Forsyth County at the 94th percentile among zone peers. Forsyth County falls in EPA Radon Region 4, one of 736 counties nationally EPA assigns to that same geologic province.

Zone vs. an actual test

Neither at the 4 pCi/L action level nor down at the roughly 1.3 pCi/L national indoor norm, Forsyth County's Zone 2 prediction lands in the gap between the two. Nothing about a Zone 2 label lowers the case for testing in Forsyth County — EPA recommends it in every zone, moderate included.

If Forsyth County tests above the action level

Nothing about Forsyth 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 North Carolina's state radon program

Forsyth County's test kit answers today; a Airthings radon monitor keeps answering for Forsyth 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 Forsyth County's numbers. Whatever zone Forsyth County carries, the zone explainer covers what it does and doesn't tell you about any one house.