Is Jackson County, IL a radon risk area?

EPA's own radon map rates Jackson County zone 2 - moderate potential, predicting a county-wide average indoor level between 2 and 4 pCi/L. Rank it against the rest of the country and Jackson County lands in the 55th percentile for radon potential.

Where Jackson County sits nationally

About 53,199 people live in Jackson County, Illinois, spread over 583.574 square miles. That works out to roughly 91 people per square mile. Rank 336 by population within its EPA zone puts Jackson County at the 68th percentile among zone peers. EPA's geology-based Region 5 groups Jackson County with 523 other counties nationally sharing its underlying rock and soil profile.

What this actually means for a house in Jackson County

EPA's Zone 2 rating for Jackson County sits below its own 4 pCi/L action level but above the national indoor average of about 1.3 pCi/L. Jackson County's Zone 2 rating sits in the middle nationally; EPA's guidance is unchanged by that — test every home regardless of its zone.

Next steps for a home in Jackson County

Nothing about Jackson 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 Illinois's state radon program

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

The methodology guide shows exactly which EPA and Census sources feed Jackson County's numbers. If you're unsure why a low zone still deserves a test, the zone explainer covers that directly.