What EPA's radon map says about Ashtabula County

Ashtabula 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. That puts Ashtabula County in the 59th percentile nationally for radon potential — higher than 59% of the counties EPA has rated.

How Ashtabula County compares

About 96,906 people live in Ashtabula County, Ohio, spread over 702.417 square miles. That works out to roughly 138 people per square mile. Among counties sharing Ashtabula County's EPA zone, it outranks 80% of them by population. Geologically, Ashtabula County is grouped into EPA Region 5 alongside 523 other counties that share its rock and soil setting.

Why the zone isn't the answer by itself

Ashtabula County's predicted average falls between EPA's 4 pCi/L action level and the national indoor average of about 1.3 pCi/L (outdoor air runs roughly 0.4 pCi/L). Ashtabula County's Zone 2 rating sits in the middle nationally; EPA's guidance is unchanged by that — test every home regardless of its zone.

If Ashtabula County tests above the action level

Mitigation cost doesn't depend on Ashtabula 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

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

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. If you're unsure why a low zone still deserves a test, the zone explainer covers that directly.