Is Fayette County, IA a radon risk area?

Fayette County is mapped as Zone 1 - Highest Potential by EPA — meaning the county-wide average indoor level is predicted above 4 pCi/L. Nationally, Fayette County ranks higher in radon potential than 81% of rated counties (the 81st percentile).

Where Fayette County sits nationally

About 19,152 people live in Fayette County, Iowa, spread over 730.817 square miles. Averaged across its land area, Fayette County runs about 26 people per square mile. Rank 589 by population within its EPA zone puts Fayette County at the 45th percentile among zone peers. Geologically, Fayette County is grouped into EPA Region 7 alongside 411 other counties that share its rock and soil setting.

Why the zone isn't the answer by itself

Fayette County's predicted average sits above EPA's own action level of 4 pCi/L — the concentration at which EPA recommends fixing a home — versus a national average around 1.3 pCi/L indoors and 0.4 pCi/L outdoors. Being in Zone 1 raises the odds Fayette County homes test above the action level, but it does not mean any specific house does — EPA recommends every home be tested, in every zone, because the only way to know is to test.

If Fayette County tests above the action level

Nothing about Fayette 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 Iowa's state radon program

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