Cotton County, OK: EPA's radon zone, explained

Cotton 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 Cotton County in the 3rd percentile nationally for radon potential — higher than 3% of the counties EPA has rated.

How Cotton County compares

Cotton County, Oklahoma is home to about 5,503 people across 632.637 square miles. Averaged across its land area, Cotton County runs about 9 people per square mile. By population, Cotton County is the 930th largest of every county sharing its EPA zone — the 10th percentile by population within that zone. Geologically, Cotton County is grouped into EPA Region 6 alongside 502 other counties that share its rock and soil setting.

What this actually means for a house in Cotton County

At Zone 3, Cotton County's predicted county average is under the national indoor average (~1.3 pCi/L) and well below EPA's 4 pCi/L action level — outdoor air nationally runs about 0.4 pCi/L for comparison. A Zone 3 label describes Cotton County's average, not any one basement or slab in it — testing is still the only way an individual homeowner actually finds out.

Testing and mitigation in Cotton County

For a Cotton 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 Oklahoma's state radon program

For Cotton County, an ongoing number beats a one-time test - a Airthings radon monitor tracks Cotton 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 Cotton County's figures come from

Cotton County's zone, rank and region all trace back to named EPA and Census sources — the methodology guide lists exactly which ones. Whatever zone Cotton County carries, the zone explainer covers what it does and doesn't tell you about any one house.