What EPA's radon map says about Cuyahoga County

EPA's own radon map rates Cuyahoga County zone 2 - moderate potential, predicting a county-wide average indoor level between 2 and 4 pCi/L. That puts Cuyahoga County in the 66th percentile nationally for radon potential — higher than 66% of the counties EPA has rated.

How Cuyahoga County compares

About 1,240,594 people live in Cuyahoga County, Ohio, spread over 457.232 square miles. Population density there runs about 2,713 people per square mile. Among counties sharing Cuyahoga County's EPA zone, it outranks 99% of them by population. EPA's geology-based Region 5 groups Cuyahoga County with 523 other counties nationally sharing its underlying rock and soil profile.

Zone vs. an actual test

Cuyahoga 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 county-wide moderate average, like Cuyahoga County's, can still hide a specific house well above or below it — testing is what actually answers the question.

If Cuyahoga County tests above the action level

Mitigation cost doesn't depend on Cuyahoga 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

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

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