Locations and reports
Radon Levels in Tennessee
What this means for you
- Your area: EPA rates 39 of Tennessee's 95 classified counties Zone 1, the highest of its three radon zones. Zones are predictions for whole counties, and homes with elevated levels occur in all three zones.
- Local tests: CDC publishes Tennessee's radon test results by county. Open your county below to see its figures.
- Your home: The only way to know your home’s level is to test it.
pCi/L (picocuries per liter) is the unit radon is measured in. EPA recommends fixing a home at 4 pCi/L or above, its action level.
For Tennessee, EPA's Map of Radon Zones places 39 of its 95 classified counties in Zone 1, highest predicted potential, a prediction for each county as a whole. Radon levels vary from home to home, so only a test measures the level in yours.
Predicted: EPA radon zone
95 of 95 counties classified
EPA classifies counties, not states. Of the 95 counties in Tennessee with a zone, 39 are in Zone 1, 32 in Zone 2 and 24 in Zone 3.
- Zone 1: Highest predicted potentialgreater than 4 pCi/L39 of 95 counties · 41.1%
- Zone 2: Moderate predicted potential2 to 4 pCi/L32 of 95 counties · 33.7%
- Zone 3: Lower predicted potentialless than 2 pCi/L24 of 95 counties · 25.3%
An EPA radon zone describes predicted potential across a whole county. It is not intended to determine whether any individual home should be tested, and homes with elevated levels occur in all three zones. EPA recommends testing every home regardless of zone, and testing is the only way to know the radon level in a specific building.
This is a county-level geologic prediction. It is not a measurement of any address, and houses with elevated radon are found in all three zones.
Predicted: EPA Map of Radon Zones
Measured: tests reported to CDC
CDC publishes Tennessee's radon test figures by county: 95 of its 95 counties have one. Each county's share is in the county list.
Tennessee, In figures
Tennessee in figures
What the published data says about Tennessee, in words. A zone and a share of tests describe an area, never the level in any one home.
Predicted
PredictedEPA places 39 of Tennessee's 95 counties in Zone 1, 32 in Zone 2 and 24 in Zone 3.
Zone 1 counties, A to Z, begin with Anderson County, Bedford County and Blount County; the county section below lists all 39.
Compared
Calculated by Radon41141% of Tennessee's counties with a zone on file are in Zone 1, a larger share than across all U.S. counties (34%). It is a share of counties, not of land, people or homes.
Reported tests
MeasuredCDC has no statewide testing figure for Tennessee on file here.
95 of the 95 counties have a published county figure; the most tests in each one's latest year were reported for Knox County (174 in 2023), Davidson County (153 in 2023) and Loudon County (94 in 2023).
Local record
Tennessee's radon program is the Tennessee Radon Program, run by Department of Environment & Conservation; its contacts are under Local resources.
3 cities have a page setting the figures of the counties it lies in side by side: Knoxville, Chattanooga and Cleveland.
Tennessee, Counties
Tennessee counties by EPA zone
PredictedAll 95 counties, by the zone EPA predicts for each. Every county has its own report.
Zone 1: highest predicted potential39
- Anderson County16.2% of reported tests at or above 4 pCi/L, 2023
- Bedford CountyReported testing not yet available
- Blount County50.0% of reported tests at or above 4 pCi/L, 2023
- Bradley County25.7% of reported tests at or above 4 pCi/L, 2023
- Claiborne County50.0% of reported tests at or above 4 pCi/L, 2023
- Davidson County27.4% of reported tests at or above 4 pCi/L, 2023
- Giles County100.0% of reported tests at or above 4 pCi/L, 2023
- Grainger County100.0% of reported tests at or above 4 pCi/L, 2023
- Greene County47.1% of reported tests at or above 4 pCi/L, 2023
- Hamblen County37.0% of reported tests at or above 4 pCi/L, 2023
- Hancock County9.1% of reported tests at or above 4 pCi/L, 2017
- Hawkins County33.3% of reported tests at or above 4 pCi/L, 2023
- Hickman County33.3% of reported tests at or above 4 pCi/L, 2023
- Humphreys CountyReported testing not yet available
- Jackson County50.0% of reported tests at or above 4 pCi/L, 2023
- Jefferson County17.1% of reported tests at or above 4 pCi/L, 2023
- Knox County17.7% of reported tests at or above 4 pCi/L, 2023
- Lawrence CountyReported testing not yet available
- Lewis County16.1% of reported tests at or above 4 pCi/L, 2017
- Lincoln County50.0% of reported tests at or above 4 pCi/L, 2023
- Loudon County40.2% of reported tests at or above 4 pCi/L, 2023
- Macon County100.0% of reported tests at or above 4 pCi/L, 2023
- Madison CountyReported testing not yet available
- Marshall CountyReported testing not yet available
- McMinn County25.0% of reported tests at or above 4 pCi/L, 2023
- Meigs CountyReported testing not yet available
- Monroe County17.6% of reported tests at or above 4 pCi/L, 2023
- Moore County35.3% of reported tests at or above 4 pCi/L, 2017
- Perry County32.5% of reported tests at or above 4 pCi/L, 2017
- Roane County20.0% of reported tests at or above 4 pCi/L, 2023
- Rutherford County20.0% of reported tests at or above 4 pCi/L, 2023
- Smith CountyReported testing not yet available
- Sullivan County37.0% of reported tests at or above 4 pCi/L, 2023
- Trousdale CountyReported testing not yet available
- Union County33.3% of reported tests at or above 4 pCi/L, 2023
- Washington County26.1% of reported tests at or above 4 pCi/L, 2023
- Wayne County66.7% of reported tests at or above 4 pCi/L, 2022
- Williamson County16.5% of reported tests at or above 4 pCi/L, 2023
- Wilson County2.4% of reported tests at or above 4 pCi/L, 2023
Zone 2: moderate predicted potential32
- Benton CountyReported testing not yet available
- Cannon CountyReported testing not yet available
- Carter CountyReported testing not yet available
- Cheatham County28.6% of reported tests at or above 4 pCi/L, 2023
- Chester CountyReported testing not yet available
- Clay CountyReported testing not yet available
- Cocke County18.4% of reported tests at or above 4 pCi/L, 2023
- Coffee CountyReported testing not yet available
- Decatur County29.4% of reported tests at or above 4 pCi/L, 2017
- DeKalb County100.0% of reported tests at or above 4 pCi/L, 2022
- Dickson County50.0% of reported tests at or above 4 pCi/L, 2023
- Fentress CountyReported testing not yet available
- Hamilton County2.4% of reported tests at or above 4 pCi/L, 2023
- Hardin County0.0% of reported tests at or above 4 pCi/L, 2022
- Henderson County16.7% of reported tests at or above 4 pCi/L, 2017
- Houston CountyReported testing not yet available
- Johnson County50.0% of reported tests at or above 4 pCi/L, 2023
- Marion County60.0% of reported tests at or above 4 pCi/L, 2023
- McNairy County8.5% of reported tests at or above 4 pCi/L, 2017
- Montgomery County40.0% of reported tests at or above 4 pCi/L, 2023
- Overton County40.0% of reported tests at or above 4 pCi/L, 2023
- Pickett CountyReported testing not yet available
- Polk County66.7% of reported tests at or above 4 pCi/L, 2023
- Putnam County23.8% of reported tests at or above 4 pCi/L, 2023
- Robertson County7.1% of reported tests at or above 4 pCi/L, 2023
- Sevier County33.3% of reported tests at or above 4 pCi/L, 2023
- Stewart CountyReported testing not yet available
- Sumner County20.0% of reported tests at or above 4 pCi/L, 2023
- Unicoi County50.0% of reported tests at or above 4 pCi/L, 2023
- Van Buren County0.0% of reported tests at or above 4 pCi/L, 2022
- Warren County50.0% of reported tests at or above 4 pCi/L, 2023
- White County25.0% of reported tests at or above 4 pCi/L, 2023
Zone 3: lower predicted potential24
- Bledsoe CountyReported testing not yet available
- Campbell County40.0% of reported tests at or above 4 pCi/L, 2023
- Carroll County0.0% of reported tests at or above 4 pCi/L, 2022
- Crockett County0.0% of reported tests at or above 4 pCi/L, 2022
- Cumberland County22.2% of reported tests at or above 4 pCi/L, 2023
- Dyer County0.0% of reported tests at or above 4 pCi/L, 2017
- Fayette CountyReported testing not yet available
- Franklin County12.5% of reported tests at or above 4 pCi/L, 2023
- Gibson CountyReported testing not yet available
- Grundy CountyReported testing not yet available
- Hardeman County20.0% of reported tests at or above 4 pCi/L, 2017
- Haywood County0.0% of reported tests at or above 4 pCi/L, 2022
- Henry County16.7% of reported tests at or above 4 pCi/L, 2017
- Lake County0.0% of reported tests at or above 4 pCi/L, 2017
- Lauderdale County11.1% of reported tests at or above 4 pCi/L, 2017
- Maury County37.5% of reported tests at or above 4 pCi/L, 2023
- Morgan County100.0% of reported tests at or above 4 pCi/L, 2023
- Obion County0.0% of reported tests at or above 4 pCi/L, 2022
- Rhea County50.0% of reported tests at or above 4 pCi/L, 2023
- Scott County0.0% of reported tests at or above 4 pCi/L, 2022
- Sequatchie CountyReported testing not yet available
- Shelby CountyReported testing not yet available
- Tipton CountyReported testing not yet available
- Weakley County12.5% of reported tests at or above 4 pCi/L, 2017
Tennessee, Cities
Cities in Tennessee with their own page
Radon data is published by county, not by city. Each city page sets the figures of the counties the city lies in side by side.
Tennessee, Local resources
Local resources in Tennessee
Who to ask in Tennessee: the state's radon program, test kits and professionals.
Tennessee Radon Program
Department of Environment & Conservation
Tennessee’s radon program answers questions about testing, mitigation and the rules where you live.
- Phone
- 1-800-232-1139
- TDEC.Radon@tn.gov
Test kits
The program says: The Tennessee Radon Program provides free radon test kits and information assistance to residents, while also providing training opportunities to radon professionals across the state.
Radon professionals
1 professional is listed in Tennessee.
Professionals in TennesseeTennessee, Questions
Questions about radon in Tennessee
Common questions9 questions, answered from the figures above
Is radon a problem in Tennessee?
EPA's Map of Radon Zones places 39 of the 95 Tennessee counties it classifies in Zone 1, the highest predicted potential, 32 in Zone 2 and 24 in Zone 3. An EPA radon zone describes predicted potential across a whole county. It is not intended to determine whether any individual home should be tested, and homes with elevated levels occur in all three zones. EPA recommends testing every home regardless of zone, and testing is the only way to know the radon level in a specific building.
How do I get a radon test in Tennessee?
EPA says you can test your home yourself or hire a qualified radon test company, and that either approach takes only a small amount of time and effort. The Tennessee radon program is the place to ask about certified testers and any test kit offer it runs.
How to test a homeFree and low-cost kits by stateTennessee radon program
Which Tennessee counties are in EPA radon Zone 1?
39 counties are in Zone 1: Anderson County, Bedford County, Blount County, Bradley County, Claiborne County, Davidson County, Giles County, Grainger County, and 31 more in the county table on this page. Zone 1 is EPA's class for highest predicted potential, a predicted average indoor screening level greater than 4 pCi/L. A zone is a prediction for a county, not a measurement of any home.
Radon in Anderson CountyRadon in Bedford CountyRadon in Blount County
Who does radon mitigation in Tennessee?
Radon411's Tennessee directory lists 1 certified radon company. EPA recommends having a qualified contractor fix a home with a radon problem, because lowering high radon levels takes technical knowledge and special skills, and some states require the work to be done by a licensed or certified professional.
How radon mitigation worksWhat mitigation costsRadon professionals in Tennessee
Which Tennessee counties have the highest radon?
95 of Tennessee's 95 counties have an EPA radon zone published here. Radon411 will not rank counties on data it does not hold, and a zone is a prediction for an area rather than a measurement of any building.
What share of radon tests in Tennessee are high?
CDC has published no statewide radon testing statistics for Tennessee, so we cannot give a figure. Where CDC does publish one, the percentage describes radon tests reported to CDC, not homes.
Which EPA region is Tennessee in?
Tennessee is in EPA Region 4: Southeast.
Do I need to test my home in Tennessee?
Yes, wherever you live in the state. Testing is the only way to know the radon level in a specific building. EPA recommends fixing a home when the radon level is 4 pCi/L or higher. EPA recommends considering a fix when the level is between 2 and 4 pCi/L.
Why does this page show coverage rather than one radon level for Tennessee?
A statewide figure averages counties with very different geology and very different numbers of reported tests, so it hides more than it shows. The county report is the level at which the EPA zone, the geologic potential and the reported testing statistics are actually published, which is why the county table above links to every one of them.
What these figures mean if you own, buy, sell or rent
The zone counts on this page describe counties across Tennessee. They are predictions for areas, and none of them measures your building.
- How to test a home
If you own your home
Test the lowest lived-in level; a short-term kit screens in days, a long-term kit reflects the year.
- Buying a house: radon guide
If you are buying
Ask for past results and any system's post-mitigation test, and test during the sale.
- Selling a house: radon guide
If you are selling
Testing before you list puts the timing in your hands; disclosure rules differ by state.
- Radon in rental homes
If you rent, or rent out a home
A tenant can test; a fix is the owner's to make, and duties differ by state.
How long a test has to run, under what conditions, and what EPA says a result means: the testing standard, in full.
Tennessee, Products
Testing and mitigation products
Whatever the figures for Tennessee show, only a test tells you about one home.
Testing
- Short-term test kitsPassive detectors exposed for a few days under closed-building conditions, then analyzed by a lab.
- Long-term test kitsDetectors exposed for more than 90 days, for a closer picture of the annual average.
- Continuous monitorsPowered devices that log radon on a repeating cycle, often used for transaction tests.
- Digital detectorsConsumer devices that display a running radon reading without a lab.
- Water radon testsKits for radon dissolved in well water, analyzed by a lab.
Mitigation
- Mitigation fansThe inline fan that keeps a soil depressurization system running, sized by the installer.
- System indicatorsU-tube manometers and fan alarms that show whether a mitigation system is still working.
- Sealing materialsCrack, joint and sump sealing used alongside a mitigation system, not instead of one.
Tennessee / Next steps
What to do next
Learn
Know what radon is
What radon is, how it gets indoors, and why a county zone is not a reading for your home.
Learn about radonTest
Test the building you live in
Short-term or long-term, where the device goes, and closed-house conditions.
How to testFix
Bring a high level down
How a mitigation system works, and the retest that confirms it.
How mitigation worksFind a pro
Hire a certified professional
Measurement and mitigation professionals by state, with their certifications.
Find a professional
Informational. Follow EPA guidance. EPA says all radon tests should be taken for a minimum of 48 hours, with windows and doors closed from 12 hours before a short-term test.