Is Ringgold County, IA a radon risk area?

EPA places Ringgold County in Zone 1 - Highest Potential — a predicted county-wide average indoor radon level above 4 pCi/L, based on the geology, soil and aerial radioactivity data behind EPA's national map. That puts Ringgold County in the 70th percentile nationally for radon potential — higher than 70% of the counties EPA has rated.

How Ringgold County compares

About 4,608 people live in Ringgold County, Iowa, spread over 535.494 square miles. That works out to roughly 9 people per square mile. Rank 934 by population within its EPA zone puts Ringgold County at the 12th percentile among zone peers. Ringgold County falls in EPA Radon Region 7, one of 412 counties nationally EPA assigns to that same geologic province.

Zone vs. an actual test

Where the national indoor average runs about 1.3 pCi/L, Ringgold County's Zone 1 rating puts its predicted county average above EPA's 4 pCi/L action level itself. A Zone 1 rating means testing is worth doing sooner rather than later, but it is still county-wide average, not a reading for any single house — some homes in Ringgold County will test well under the action level, and EPA's guidance is to test regardless of zone.

Next steps for a home in Ringgold County

Nothing about Ringgold 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

Ringgold County's test kit answers today; a Airthings radon monitor keeps answering for Ringgold County over time. Affiliate link, RadonZoneCheck earns a commission there, at no extra cost to you. Code RADONZONE-10OFF takes 10% off at checkout.

More on how this number was built

Ringgold 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.