What EPA's radon map says about Giles County

EPA places Giles County in Zone 1 - Highest Potential — a predicted county-wide average indoor radon level above 4 pCi/L, based on the geology, soil and aerial radioactivity data behind EPA's national map. Rank it against the rest of the country and Giles County lands in the 85th percentile for radon potential.

Where Giles County sits nationally

About 30,971 people live in Giles County, Tennessee, spread over 610.931 square miles. Averaged across its land area, Giles County runs about 51 people per square mile. Among counties sharing Giles County's EPA zone, it outranks 57% of them by population. Giles County falls in EPA Radon Region 4, one of 736 counties nationally EPA assigns to that same geologic province.

Zone vs. an actual test

Fixing a home becomes an EPA recommendation past 4 pCi/L, and that is precisely the side of the line Giles County's Zone 1 prediction lands on, well above the roughly 1.3 pCi/L most US homes average. Some Giles County homes will test comfortably under the action level despite the county's Zone 1 rating — the only way to know which kind of home you have is an actual test.

If Giles County tests above the action level

Mitigation cost doesn't depend on Giles 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 Tennessee's state radon program

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

Giles County's zone, rank and region all trace back to named EPA and Census sources — the methodology guide lists exactly which ones. Whatever zone Giles County carries, the zone explainer covers what it does and doesn't tell you about any one house.