Is Clay County, AR a radon risk area?

EPA places Clay County in Zone 3 - Low Potential — a predicted county-wide average indoor radon level below 2 pCi/L, based on the geology, soil and aerial radioactivity data behind EPA's national map. That puts Clay County in the 10th percentile nationally for radon potential — higher than 10% of the counties EPA has rated.

Where Clay County sits nationally

About 14,112 people live in Clay County, Arkansas, spread over 639.224 square miles. Averaged across its land area, Clay County runs about 22 people per square mile. Rank 729 by population within its EPA zone puts Clay County at the 29th percentile among zone peers. EPA's geology-based Region 6 groups Clay County with 502 other counties nationally sharing its underlying rock and soil profile.

Why the zone isn't the answer by itself

Well clear of both the 1.3 pCi/L national indoor average and EPA's 4 pCi/L action level, Clay County's Zone 3 prediction is the low end of the scale. Don't read Zone 3 as a pass for Clay County — EPA's guidance to test every home makes no exception for counties predicted low.

Next steps for a home in Clay County

Nothing about Clay 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 Arkansas's state radon program

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