Montgomery County, TN: EPA's radon zone, explained

Montgomery 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, Montgomery County ranks higher in radon potential than 63% of rated counties (the 63rd percentile).

Montgomery County by the numbers

Montgomery County, Tennessee is home to about 246,025 people across 539.169 square miles. That works out to roughly 456 people per square mile. By population, Montgomery County is the 96th largest of every county sharing its EPA zone — the 91st percentile by population within that zone. Geologically, Montgomery County is grouped into EPA Region 4 alongside 735 other counties that share its rock and soil setting.

Zone vs. an actual test

Montgomery 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 Zone 2 rating is a moderate county-wide average, not a guarantee about any one house in Montgomery County — testing is the only way to know an individual home's actual level.

If Montgomery County tests above the action level

For a Montgomery 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 Tennessee's state radon program

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

Where Montgomery County's figures come from

The methodology guide shows exactly which EPA and Census sources feed Montgomery County's numbers. Whatever zone Montgomery County carries, the zone explainer covers what it does and doesn't tell you about any one house.