Sharp County, AR: EPA's radon zone, explained

EPA places Sharp 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 Sharp County in the 45th percentile nationally for radon potential — higher than 45% of the counties EPA has rated.

Where Sharp County sits nationally

Sharp County, Arkansas is home to about 18,130 people across 604.637 square miles. Averaged across its land area, Sharp County runs about 30 people per square mile. By population, Sharp County is the 659th largest of every county sharing its EPA zone — the 36th percentile by population within that zone. EPA's geology-based Region 6 groups Sharp County with 502 other counties nationally sharing its underlying rock and soil profile.

Zone vs. an actual test

Sharp County's predicted average falls between EPA's 4 pCi/L action level and the national indoor average of about 1.3 pCi/L (outdoor air runs roughly 0.4 pCi/L). A county-wide moderate average, like Sharp County's, can still hide a specific house well above or below it — testing is what actually answers the question.

Testing and mitigation in Sharp County

For a Sharp County homeowner, the order is simple: test first, since a kit costs a small fraction of what mitigation would. Only if the result clears 4 pCi/L does a system — typically $800–$2,500, about $1,200 for a common install — become worth pricing out.

Find Arkansas's state radon program

For Sharp County, an ongoing number beats a one-time test - a Airthings radon monitor tracks Sharp County's levels over time. RadonZoneCheck earns a commission there, at no extra cost to you. Code RADONZONE-10OFF takes 10% off at checkout.

Where Sharp County's figures come from

The methodology guide shows exactly which EPA and Census sources feed Sharp County's numbers. Whatever zone Sharp County carries, the zone explainer covers what it does and doesn't tell you about any one house.