Tennessee radon statistics
38 of Tennessee's 95 counties are in EPA's highest radon-potential zone, and about 1 in 4 Tennessee homes that request a free state test kit test above EPA's 4 pCi/L action level (Tennessee Radon Program). Homes needing action have been found in every Tennessee county.
What are the key radon numbers for Tennessee?
| Statistic | Value | Source |
|---|---|---|
| Counties in EPA Zone 1 (highest potential, predicted average above 4 pCi/L) | 38 | EPA |
| Counties in EPA Zone 2 (2 to 4 pCi/L) | 30 | EPA |
| Counties in EPA Zone 3 (below 2 pCi/L) | 26 | EPA |
| Counties with no EPA zone assigned | 1 (Pickett) | EPA |
| Share of free state kits testing above 4 pCi/L | About 1 in 4 | TDEC |
| Free test kits the state program distributes | About 6,000 a year | TDEC |
| U.S. lung cancer deaths linked to radon each year | About 21,000 | EPA |
| Average U.S. indoor radon level | About 1.3 pCi/L | EPA |
| State license required for radon testers or mitigators | No | Indoor Environments Association |
Which Tennessee counties are in EPA Radon Zone 1?
Anderson, Bedford, Blount, Bradley, Claiborne, Davidson, Giles, Grainger, Greene, Hamblen, Hancock, Hawkins, Hickman, Humphreys, Jackson, Jefferson, Knox, Lawrence, Lewis, Lincoln, Loudon, Marshall, Maury, McMinn, Meigs, Monroe, Moore, Perry, Roane, Rutherford, Smith, Sullivan, Trousdale, Union, Washington, Wayne, Williamson, Wilson.
What do radon tests show in each Tennessee county?
The table lists each county's EPA zone and the 2022–2023 test figures from the Tennessee Department of Health's radon testing dashboard, in pCi/L. Figures are shown only where they were confirmed on repeat checks or seen once (provisional). These are self-selected tests, not a random survey, and a missing figure never means radon is absent. Download the table (CSV) · JSON
| County | Region | EPA zone | Average | Median | Maximum | State data status |
|---|---|---|---|---|---|---|
| Anderson | East | Zone 1 | 2.1 | 1.4 | 6.2 | State test figures confirmed on repeat checks |
| Bedford | Middle | Zone 1 | – | – | – | State test figures couldn't be confirmed, so they aren't shown |
| Benton | West | Zone 2 | 3.8 | – | – | State test figures confirmed on repeat checks |
| Bledsoe | East | Zone 3 | – | – | – | State test figures couldn't be confirmed, so they aren't shown |
| Blount | East | Zone 1 | 6.7 | 2.2 | 18.2 | State test figures confirmed on repeat checks |
| Bradley | East | Zone 1 | 4.5 | 1.9 | 19.5 | State test figures confirmed on repeat checks |
| Campbell | East | Zone 3 | 3.7 | 0.8 | 7.2 | State test figures seen once; shown with a caveat |
| Cannon | Middle | Zone 2 | 0.9 | 0.8 | 1.3 | State test figures confirmed on repeat checks |
| Carroll | West | Zone 3 | – | – | – | State test figures couldn't be confirmed, so they aren't shown |
| Carter | East | Zone 2 | – | – | – | State test figures couldn't be confirmed, so they aren't shown |
| Cheatham | Middle | Zone 2 | – | 1.5 | 5.3 | State test figures seen once; shown with a caveat |
| Chester | West | Zone 2 | 1.0 | 1.0 | 1.2 | State test figures confirmed on repeat checks |
| Claiborne | East | Zone 1 | – | – | – | State test figures couldn't be confirmed, so they aren't shown |
| Clay | Middle | Zone 3 | 2.5 | 1.1 | 2.6 | State test figures seen once; shown with a caveat |
| Cocke | East | Zone 2 | – | – | – | State test figures couldn't be confirmed, so they aren't shown |
| Coffee | Middle | Zone 2 | 1.3 | 0.6 | – | State test figures seen once; shown with a caveat |
| Crockett | West | Zone 3 | 0.9 | – | – | State test figures confirmed on repeat checks |
| Cumberland | East | Zone 3 | 2.3 | – | 7.0 | State test figures confirmed on repeat checks |
| Davidson | Middle | Zone 1 | 2.8 | – | 38.0 | State test figures seen once; shown with a caveat |
| DeKalb | Middle | Zone 2 | 59.7 | 59.2 | 62.3 | State test figures confirmed on repeat checks |
| Decatur | West | Zone 2 | – | – | – | No 2022–2023 state test records for this county |
| Dickson | Middle | Zone 2 | 5.1 | 1.6 | 7.8 | State test figures confirmed on repeat checks |
| Dyer | West | Zone 3 | – | – | – | No 2022–2023 state test records for this county |
| Fayette | West | Zone 3 | 2.3 | 1.3 | – | State test figures confirmed on repeat checks |
| Fentress | Middle | Zone 2 | – | – | – | State test figures couldn't be confirmed, so they aren't shown |
| Franklin | Middle | Zone 3 | – | – | – | State test figures couldn't be confirmed, so they aren't shown |
| Gibson | West | Zone 3 | 0.9 | 0.8 | 1.7 | State test figures seen once; shown with a caveat |
| Giles | Middle | Zone 1 | 4.3 | 1.5 | 4.4 | State test figures confirmed on repeat checks |
| Grainger | East | Zone 1 | – | – | – | State test figures couldn't be confirmed, so they aren't shown |
| Greene | East | Zone 1 | – | – | – | State test figures couldn't be confirmed, so they aren't shown |
| Grundy | Middle | Zone 3 | – | – | – | State test figures couldn't be confirmed, so they aren't shown |
| Hamblen | East | Zone 1 | – | – | – | State test figures couldn't be confirmed, so they aren't shown |
| Hamilton | East | Zone 2 | 2.1 | 0.7 | 35.3 | State test figures confirmed on repeat checks |
| Hancock | East | Zone 1 | – | – | – | State test figures couldn't be confirmed, so they aren't shown |
| Hardeman | West | Zone 3 | – | – | – | No 2022–2023 state test records for this county |
| Hardin | West | Zone 2 | 1.8 | 1.8 | 1.8 | State test figures confirmed on repeat checks |
| Hawkins | East | Zone 1 | – | – | – | State test figures couldn't be confirmed, so they aren't shown |
| Haywood | West | Zone 3 | – | – | – | State test figures couldn't be confirmed, so they aren't shown |
| Henderson | West | Zone 2 | – | – | – | No 2022–2023 state test records for this county |
| Henry | West | Zone 3 | – | – | – | No 2022–2023 state test records for this county |
| Hickman | Middle | Zone 1 | – | – | 4.4 | State test figures seen once; shown with a caveat |
| Houston | Middle | Zone 2 | – | – | – | State test figures couldn't be confirmed, so they aren't shown |
| Humphreys | Middle | Zone 1 | – | – | – | State test figures couldn't be confirmed, so they aren't shown |
| Jackson | Middle | Zone 1 | 2.3 | 1.6 | 3.8 | State test figures seen once; shown with a caveat |
| Jefferson | East | Zone 1 | – | – | – | State test figures couldn't be confirmed, so they aren't shown |
| Johnson | East | Zone 2 | 4.5 | – | 6.4 | State test figures seen once; shown with a caveat |
| Knox | East | Zone 1 | – | – | 18.2 | State test figures confirmed on repeat checks |
| Lake | West | Zone 3 | – | – | – | No 2022–2023 state test records for this county |
| Lauderdale | West | Zone 3 | – | – | – | No 2022–2023 state test records for this county |
| Lawrence | Middle | Zone 1 | – | – | – | State test figures couldn't be confirmed, so they aren't shown |
| Lewis | Middle | Zone 1 | – | – | – | No 2022–2023 state test records for this county |
| Lincoln | Middle | Zone 1 | 2.0 | – | 4.3 | State test figures confirmed on repeat checks |
| Loudon | East | Zone 1 | – | – | – | State test figures couldn't be confirmed, so they aren't shown |
| Macon | Middle | Zone 2 | – | – | – | State test figures couldn't be confirmed, so they aren't shown |
| Madison | West | Zone 3 | 2.0 | 1.6 | – | State test figures confirmed on repeat checks |
| Marion | East | Zone 3 | 5.2 | 4.6 | 10.2 | State test figures confirmed on repeat checks |
| Marshall | Middle | Zone 1 | 0.9 | 0.9 | 0.9 | State test figures confirmed on repeat checks |
| Maury | Middle | Zone 1 | 5.9 | 3.0 | 12.5 | State test figures confirmed on repeat checks |
| McMinn | East | Zone 1 | 2.1 | 1.4 | 2.5 | State test figures confirmed on repeat checks |
| McNairy | West | Zone 2 | – | – | – | No 2022–2023 state test records for this county |
| Meigs | East | Zone 1 | – | – | – | State test figures couldn't be confirmed, so they aren't shown |
| Monroe | East | Zone 1 | 2.0 | – | 9.1 | State test figures confirmed on repeat checks |
| Montgomery | Middle | Zone 2 | 4.6 | 1.6 | 9.4 | State test figures confirmed on repeat checks |
| Moore | Middle | Zone 1 | – | – | – | State test figures couldn't be confirmed, so they aren't shown |
| Morgan | East | Zone 3 | – | – | – | State test figures couldn't be confirmed, so they aren't shown |
| Obion | West | Zone 3 | 1.6 | – | – | State test figures confirmed on repeat checks |
| Overton | Middle | Zone 2 | 7.4 | 0.7 | 32.1 | State test figures confirmed on repeat checks |
| Perry | Middle | Zone 1 | – | – | – | No 2022–2023 state test records for this county |
| Pickett | Middle | Not assigned | – | – | – | State test figures couldn't be confirmed, so they aren't shown |
| Polk | East | Zone 2 | – | – | – | State test figures couldn't be confirmed, so they aren't shown |
| Putnam | Middle | Zone 2 | – | – | – | State test figures couldn't be confirmed, so they aren't shown |
| Rhea | East | Zone 3 | – | – | – | State test figures couldn't be confirmed, so they aren't shown |
| Roane | East | Zone 1 | 2.3 | 1.6 | 8.4 | State test figures seen once; shown with a caveat |
| Robertson | Middle | Zone 2 | 2.8 | 0.8 | 5.9 | State test figures confirmed on repeat checks |
| Rutherford | Middle | Zone 1 | – | – | 3.9 | State test figures confirmed on repeat checks |
| Scott | East | Zone 3 | – | – | – | State test figures couldn't be confirmed, so they aren't shown |
| Sequatchie | Middle | Zone 3 | 0.8 | – | – | State test figures seen once; shown with a caveat |
| Sevier | East | Zone 2 | 4.6 | 1.8 | 13.5 | State test figures seen once; shown with a caveat |
| Shelby | West | Zone 3 | – | – | – | State test figures couldn't be confirmed, so they aren't shown |
| Smith | Middle | Zone 1 | 2.0 | – | 2.9 | State test figures confirmed on repeat checks |
| Stewart | Middle | Zone 2 | – | – | – | No 2022–2023 state test records for this county |
| Sullivan | East | Zone 1 | – | – | – | State test figures couldn't be confirmed, so they aren't shown |
| Sumner | Middle | Zone 2 | 2.4 | 1.4 | 9.3 | State test figures confirmed on repeat checks |
| Tipton | West | Zone 3 | – | – | – | State test figures couldn't be confirmed, so they aren't shown |
| Trousdale | Middle | Zone 1 | – | – | – | State test figures couldn't be confirmed, so they aren't shown |
| Unicoi | East | Zone 2 | – | – | – | State test figures couldn't be confirmed, so they aren't shown |
| Union | East | Zone 1 | – | – | – | State test figures couldn't be confirmed, so they aren't shown |
| Van Buren | Middle | Zone 2 | 2.0 | – | – | State test figures confirmed on repeat checks |
| Warren | Middle | Zone 2 | – | – | – | State test figures couldn't be confirmed, so they aren't shown |
| Washington | East | Zone 1 | – | – | – | State test figures couldn't be confirmed, so they aren't shown |
| Wayne | Middle | Zone 1 | 9.7 | 10.2 | 17.4 | State test figures confirmed on repeat checks |
| Weakley | West | Zone 3 | – | – | – | No 2022–2023 state test records for this county |
| White | Middle | Zone 2 | 6.5 | 1.6 | 8.9 | State test figures confirmed on repeat checks |
| Williamson | Middle | Zone 1 | – | – | 17.2 | State test figures confirmed on repeat checks |
| Wilson | Middle | Zone 1 | 2.5 | 0.9 | 9.5 | State test figures confirmed on repeat checks |
Sources: EPA Map of Radon Zones: Tennessee · Tennessee Department of Health, Tennessee Radon Testing dashboard (2022–2023) · Tennessee Radon Program · EPA, Health Risk of Radon
Last reviewed October 17, 2026 by the Tennessee Radon Authority editorial team. How we research.