Humphreys County Radon · Tennessee
Humphreys County is EPA Radon Zone 1, yet unincorporated areas enforce no residential building code. In Waverly and New Johnsonville, today's radon provisions cannot be verified online. Testing is the only reliable way to know a home's radon level.
EPA zone: Zone 1Region: Middle TennesseeState test data: State test figures couldn't be confirmed, so they aren't shown
Yes, it can be. Humphreys County is in EPA Zone 1, the highest radon-potential category, where the predicted average indoor screening level is above 4 pCi/L. Levels vary from house to house, so a test is the only way to know your home's level.
No, not outside city limits: unincorporated Humphreys County has no residential code enforcement. Waverly's published code has no radon appendix, and New Johnsonville's current code couldn't be confirmed. Local code details
Order a free short-term kit from the Tennessee Radon Program online or by calling 1-800-232-1139. Place it on the lowest lived-in floor, about 3 feet off the floor, for 3 to 5 days, then mail it back right away. How to test your home
EPA recommends fixing your home if radon is 4 pCi/L or higher, and considering a fix between 2 and 4 pCi/L. Confirm a high short-term result with a second test first. What your result means
Tennessee doesn't license radon professionals, so look for NRPP or NRSB certification. Search both national directories by ZIP code; certified professionals often serve Humphreys County from nearby cities. How to choose a radon professional
Unincorporated Humphreys County has no residential code enforcement. The two cities issue permits, but their current code editions and radon appendices are not published online.
The county website shows no building, inspection, planning, zoning, or code-enforcement department, and Humphreys County is absent from the State Fire Marshal's residential-permit jurisdiction list. Whether the county formally opted out or never participated could not be verified online. 12
No county code department is published, and the county is outside the state's residential permit program. 12
Waverly issues permits and conducts inspections. Its published 2008 code lists no appendices, and the 2006 IRC has no radon appendix. A newer adoption is likely but unverified. 34
The city has Planning & Zoning and issues permits, but its MTAS code is too old to establish today's requirements. 5
EPA's zone classification is publishable. The Tennessee dashboard's Humphreys County average, median, and maximum are withheld because they could not be reproduced.
Highest potential: predicted average indoor levels may exceed 4 pCi/L. Elevated homes can occur in every zone. 67
The tooltip label was confirmed as “Humphreys,” but its numeric values were not exposed to the accessibility tree and the dashboard offers no CSV/data export.
State test figures that couldn't be confirmed on repeat checks aren't shown here. A missing figure doesn't mean radon is absent; test your home to know its level.
Tennessee doesn't license radon testers or mitigators, so national certification is the best way to check qualifications. The Tennessee Radon Program points residents to two directories: search them by ZIP code and widen the radius if nothing is listed nearby.
We don't recommend or rank companies. Before you hire, check the certification number in the directory yourself and ask for a follow-up test after any system is installed. Questions to ask a radon professional.
Tennessee's seller disclosure asks about known radon hazards, but sellers do not have to test or investigate. Buyers can make a professional radon test part of the contract.
Zone 1 and the lack of a county code backstop mean age is not assurance. No verified countywide radon-resistant construction requirement exists.
The state form permits Yes, No, or Unknown based on the seller's knowledge; it is not a warranty and does not require an investigation. 11
The disclosure form advises buyers to include radon inspection contingencies. Arrange the test rather than relying on prior knowledge. 11
The Tennessee Department of Environment and Conservation's statewide Radon Program offers free test kits to homeowners. 12
Tennessee's statewide radon program offers free kits to homeowners.
TDEC Radon Program ↗Search the national directory by ZIP and review certification details.
Search NRPP ↗Search for a Radon Measurement Specialist serving your area.
Search NRSB ↗The published record is stale or incomplete in both cities. These are evidence gaps, not assumptions about current enforcement.
Verified-live citations were checked on October 16, 2026. “Not verified” means the available public record or interface did not support the claim; it does not mean the answer is negative.