Is Cooper County, MO a radon risk area?

EPA places Cooper 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. Cooper County sits at the 45th percentile nationally for radon potential — above 45 of every 100 rated counties.

Where Cooper County sits nationally

About 17,122 people live in Cooper County, Missouri, spread over 564.746 square miles. Population density there runs about 30 people per square mile. Rank 670 by population within its EPA zone puts Cooper County at the 35th percentile among zone peers. Geologically, Cooper County is grouped into EPA Region 7 alongside 411 other counties that share its rock and soil setting.

What this actually means for a house in Cooper County

Cooper County's Zone 2 prediction clears the 1.3 pCi/L national indoor average without reaching EPA's own 4 pCi/L point for recommending a fix. A Zone 2 rating is a moderate county-wide average, not a guarantee about any one house in Cooper County — testing is the only way to know an individual home's actual level.

If Cooper County tests above the action level

Nothing about Cooper 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 Missouri's state radon program

Cooper County's test kit answers today; a Airthings radon monitor keeps answering for Cooper 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

Cooper County's zone, rank and region all trace back to named EPA and Census sources — the methodology guide lists exactly which ones. The guide to what a radon zone actually means covers why testing matters in every zone, not just Zone 1.