Long-term kit
RL416 long-term radon test kit, lab fee included
- Lab fee included
Method: Alpha track
In home: 90 days to 12 months
Locations and reports
Radon Levels in McMinn County, Tennessee
EPA puts McMinn County in Zone 1, its highest radon zone, and only 4 radon tests from it are on file with CDC (2023). Homes with elevated levels occur in all three zones, so only a test measures yours.
Data checked By Radon411Methodology
Share at 4+ pCi/L
34.0%
0.7 pts above TN
- McMinn
- 34.0%
- Tennessee
- 33.3%
106 tests, 2008 to 2017
Median result
2.8pCi/L
Below action level
- McMinn
- 2.8 pCi/L
- EPA
- 4.0 pCi/L
Midpoint of the tests, 2008 to 2017
Tests reported
106
44th of 80 by tests
- McMinn
- 106
- Davidson
- 5,592
Reported to CDC before any fix, 2008 to 2017
EPA radon zone
Zone 1
Highest potential
- Zone 1
- 2
- 3
1 highest, 3 lowest
EPA predicts over 4 pCi/L indoors
Rank in Tennessee
34 of 80
Middle half
- McMinn
- 34.0%
- Jefferson
- 56.8%
By share, of 80 with 30+ tests
Read a result for McMinn County
Starts at McMinn County's median, 2.8 pCi/L
EPA’s own thresholds; the figures are the area’s, never this home’s.
EPA’s reading of 2.8 pCi/L
Between 2 and 4 pCi/L
- Under 20 to 1.9 pCi/L
- 2 to 4consider a fix
- 4 and aboveEPA says fix it
This result is between 2 and 4 pCi/L. EPA recommends considering a fix when the level is between 2 and 4 pCi/L. McMinn County's median reported result, 2008 to 2017.
The data
McMinn County, At a glance
McMinn County at a glance
Predicted: EPA radon zone
EPA Zone 1: highest predicted potential
EPA puts all of McMinn County in
USGS geologic potential: High across 100% of the county's area
Predicted: EPA Map of Radon Zones
Measured: tests reported to CDC
Radon tests reported for McMinn County, 2023
| Year | Share of reported tests at or above 4 pCi/L |
|---|---|
| 2022 | 0.0% |
| 2023 | 25.0% |
2023: 25.0%. Across these years the share ran from 0.0% to 25.0%. Each column counts radon tests reported to CDC that year, not homes.
What these figures count
Only 4 tests were reported to CDC for McMinn County over 2023, and tests are often run on homes being sold or already suspected of a problem: so few describe neither the county nor this house.
Measured: CDC tracking data. Figure above: 2023. Measured data period: 2005 to 2023 (every CDC figure on file).
McMinn County, Compared
McMinn County radon figures, compared
Calculated by Radon411In McMinn County, about 3 in 10 reported tests over the 2008 to 2017 laboratory totals (36 of 106) were at or above EPA's action level. Against the national pool of 35.7%, the gap is 1.7 points lower. Across 95 Tennessee counties pooled together, 33.3% of tests reached that level, so McMinn County runs 0.7 points above its state.
The newest figure, in 2023, counts only 4 tests (25.0% at or above 4 pCi/L), too few to compare, so this reading uses the 106-test figure.
Of 5 neighbours with a figure, 2 reported a larger share at or above 4 pCi/L and 3 a smaller one; the spread is 20.9% (Bradley County) to 54.5% (Loudon County). By share, McMinn County is 34th of 80 Tennessee counties with 30 or more tests for the same period.
Half the tests came in under 2.8 pCi/L and half over it; the single highest reached 18.2 pCi/L. Below the action level, 28 tests (26.4%) came in under 2 pCi/L, against 42.4% statewide, and 42 tests (39.6%) fell between 2 and 4, against 24.3% statewide.
Zone 1 on EPA's map (predicted average above 4 pCi/L) and a 34.0% share point the same way here. USGS geology rates 100% of the county's land high radon potential. CDC also counts 5 tests taken after mitigation in McMinn County for the same period: tests in homes where a fix was already in.
The busiest year on file was 2022, with 15 tests reported; the quietest, 2023, had 4.
Pooled shares: Radon411's sum of CDC's county counts for one period.
McMinn County, Geology
The ground under McMinn County
PredictedUSGS's geologic map puts all of McMinn County's mapped land in one class: high radon potential. All of it lies in the area the map calls Ridge and Valley, to which USGS gives a radon index of 14, in the high band (12 to 17).
| Area | The rock, in USGS's words | Potential | Radon index | Share of land |
|---|---|---|---|---|
| Ridge and Valley | Paleozoic sandstone and cherty dolostone. | High | 14 | 100% |
Names, descriptions and indexes: U.S. Geological Survey, Geologic Radon Potential Map (2025). Shares: Radon411, from the map cut to the boundary.
McMinn County beside the ground around it
McMinn County has more high-potential ground than Tennessee as a whole: 100% of its land against 47.2%. Of the 6 counties that border it, none has as large a share of high-potential ground; Loudon County comes nearest at 100%.
The map rates the ground, not the air in any home.
Local help
McMinn County, Local resources
Radon testing and mitigation in McMinn County
- Tennessee Radon ProgramTennessee Radon Program, run by Department of Environment & Conservation, offers free or discounted test kits, and answers questions about testing and mitigation in Tennessee.Visit the program’s page(opens in a new tab)
- Free and low-cost kitsThe 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.
- Compare kits
- Professionals in Tennessee1 professional is listed in Tennessee.
What Tennessee's program says
- Phone
- 1-800-232-1139
- TDEC.Radon@tn.gov
What it means
McMinn County, Questions
Questions about radon in McMinn County
Are radon levels high in McMinn County?
In 2023, 25.0% of the radon tests reported to CDC for McMinn County, Tennessee were at or above 4 pCi/L, and the median reported pre-mitigation result was 1.6 pCi/L. Of 80 Tennessee counties with 30 or more tests for the same period, 33 reported a higher share; pooled, the state comes to 33.3%.
Which counties border McMinn County?
McMinn County borders 6 counties: Meigs County, Polk County, Monroe County, Bradley County, Loudon County and Roane County.
Products
McMinn County, Products
Testing a home in McMinn County
In McMinn County, 34.0% of 106 tests reported to CDC over the 2008 to 2017 laboratory totals reached 4 pCi/L, against 33.3% pooled across Tennessee. In Zone 1 the year-round level in McMinn County is the one to know: a long-term test (more than 90 days) or a monitor, with a short-term kit for a first answer.
Test kits and monitors3
See every kit and monitorMonitorSafetySiren
Pro4 plug-in radon detector with a display and alarm
- C-NRPP 2024/25: Not included
- Plug-in
- Alarm
- Screen
First reading: Within 48 hours
Short-term kit
Radon Short Term Test Kit short-term charcoal radon test kit, lab fee included
- Lab fee included
Method: Charcoal
In home: 2 to 7 days
- See every kit and monitor Test kits and monitors
Test kits and monitors: 1 of 3
McMinn County is in EPA Zone 1, the highest predicted radon potential. Best radon monitors for Zone 1 counties like McMinn County
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McMinn County, Bordering counties
Counties bordering McMinn County
Calculated by Radon411- Radon levels in Loudon CountyEPA zone 1
54.5%at or above 4 pCi/L
Median 4.4 pCi/L · 859 tests · 20.5 points above McMinn County
- Radon levels in Monroe CountyEPA zone 1
45.5%at or above 4 pCi/L
Median 3.5 pCi/L · 189 tests · 11.5 points above McMinn County
- Radon levels in Meigs CountyEPA zone 1
34.5%at or above 4 pCi/L
Median 2.5 pCi/L · 29 tests · 0.5 points above McMinn County
- Radon levels in Roane CountyEPA zone 1
33.7%at or above 4 pCi/L
Median 2.5 pCi/L · 258 tests · 0.3 points below McMinn County
- Radon levels in Polk CountyEPA zone 2
27.9%at or above 4 pCi/L
Median 2.2 pCi/L · 43 tests · 6.1 points below McMinn County
- Radon levels in Bradley CountyEPA zone 1
20.9%at or above 4 pCi/L
Median 1.9 pCi/L · 425 tests · 13.1 points below McMinn County
McMinn County, Cities and towns
Cities and towns in McMinn County
McMinn County is growing: the Census Bureau puts it at 57,404 residents on July 1, 2025, up 7.6% from 53,347 in 2020. That works out to 133 people per square mile of land. Its largest town, Athens, has 15,263 residents, 26.6% of the total. Reported testing is thin here: 106 tests over 2008 to 2017, or 1.8 for every 1,000 residents (2025 estimate), where Tennessee as a whole comes to 4.2.
From Athens to Calhoun, CDC publishes no figure by town: each reads McMinn County's.
| Place | Residents | Since 2020 | Share of residents |
|---|---|---|---|
| Athens | 15,263 | +8.2% | 26.6% |
| Sweetwaterextends beyond McMinn County | 6,706 | +4.3% | Counted whole |
| Etowah | 3,786 | +5.1% | 6.6% |
| Englewood | 1,610 | +8.8% | 2.8% |
| Niota | 833 | +8.2% | 1.5% |
| Calhoun | 571 | +5.9% | 1.0% |
6 incorporated places, as listed in the U.S. Census Bureau’s 2020 place reference files. Residents: U.S. Census Bureau population estimates for July 1, 2025 (Vintage 2025). A place that extends beyond McMinn County is counted whole, so it has no share.
McMinn County, Homes
Homes in McMinn County
Of McMinn County's 24,027 homes, 71% are detached houses, against 68% across Tennessee; 18% are mobile homes. Half of its homes were built before 1983, close to Tennessee's 1986: 23% date from before 1960 and 26% from 2000 or later. 75% of occupied homes are lived in by their owner (Tennessee: 67%); in the rest a tenant can run a test, but a fix is the landlord's to make.
| Homes | McMinn County | Tennessee |
|---|---|---|
| Housing units | 24,027 | 3,095,472 |
| Detached houses | 71% | 68% |
| In buildings of 5 or more | 4% | 14% |
| Mobile homes | 18% | 8% |
| Built before 1960 | 23% | 18% |
| Built since 2000 | 26% | 29% |
| Middle year built | 1983 | 1986 |
| Owner-occupied | 75% | 67% |
Census Bureau, American Community Survey, 2019 to 2023: estimates from a sample of homes, looser for a small place. Shares by Radon411.