What EPA's radon map says about Lake County

Lake County is mapped as Zone 2 - Moderate Potential by EPA — meaning the county-wide average indoor level is predicted between 2 and 4 pCi/L. Nationally that's the 63rd percentile for radon potential — Lake County outranks 63% of every county EPA has rated.

How Lake County compares

About 232,360 people live in Lake County, Ohio, spread over 229.395 square miles. That works out to roughly 1,013 people per square mile. Among counties sharing Lake County's EPA zone, it outranks 90% of them by population. Lake County falls in EPA Radon Region 5, one of 524 counties nationally EPA assigns to that same geologic province.

What this actually means for a house in Lake County

Call it a middle case: above the 1.3 pCi/L most US homes average, below the 4 pCi/L line EPA uses to recommend mitigation — that's Lake County's Zone 2 prediction. Middle-of-the-pack doesn't mean risk-free for any one Lake County address — a moderate county average still leaves individual homes to test either side of it.

Next steps for a home in Lake County

Mitigation cost doesn't depend on Lake County's zone — it depends on the house's foundation. A typical system runs $800–$2,500 (about $1,200 typical), and testing first is what tells you whether that's needed at all.

Find Ohio's state radon program

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

The methodology guide shows exactly which EPA and Census sources feed Lake County's numbers. The guide to what a radon zone actually means covers why testing matters in every zone, not just Zone 1.