Woodford County, IL Radon Zone Data

Woodford County, IL: EPA's radon zone, explained

Woodford County is mapped as Zone 1 - Highest Potential by EPA — meaning the county-wide average indoor level is predicted above 4 pCi/L. Nationally, Woodford County ranks higher in radon potential than 87% of rated counties (the 87th percentile).

How Woodford County compares

Woodford County, Illinois is home to about 38,290 people across 527.557 square miles. That works out to roughly 73 people per square mile. By population, Woodford County is the 392nd largest of every county sharing its EPA zone — the 63rd percentile by population within that zone. Geologically, Woodford County is grouped into EPA Region 5 alongside 523 other counties that share its rock and soil setting.

What this actually means for a house in Woodford County

Woodford County's predicted average sits above EPA's own action level of 4 pCi/L — the concentration at which EPA recommends fixing a home — versus a national average around 1.3 pCi/L indoors and 0.4 pCi/L outdoors. That doesn't mean every Woodford County house tests high — a zone is a county-wide prediction, never a single-home reading — but it's a reason to test sooner rather than let it wait.

Next steps for a home in Woodford County

For a Woodford 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 Illinois's state radon program

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

Where Woodford County's figures come from

Every figure on this page traces to EPA's own Map of Radon Zones and Census data, documented in the methodology guide. Whatever zone Woodford County carries, the zone explainer covers what it does and doesn't tell you about any one house.