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 Anderson County, Tennessee
EPA puts Anderson County in Zone 1, its highest radon zone, and 16.2% of its 37 reported radon tests (2023) were at or above 4 pCi/L. Homes with elevated levels occur in all three zones, so only a test measures yours.
Data checked By Radon411Methodology
Share at 4+ pCi/L
16.2%
8.7 pts below TN
- Anderson
- 16.2%
- Tennessee
- 24.9%
37 tests, 2023
Median result
1.4pCi/L
Below action level
- Anderson
- 1.4 pCi/L
- EPA
- 4.0 pCi/L
Midpoint of the tests, 2023
Tests reported
37
13th of 15 by tests
- Anderson
- 37
- Hamblen
- 594
Reported to CDC before any fix, 2023
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
13 of 15
Lowest quarter
- Anderson
- 16.2%
- Blount
- 50.0%
By share, of 15 with 30+ tests
Read a result for Anderson County
Starts at Anderson County's median, 1.4 pCi/L
EPA’s own thresholds; the figures are the area’s, never this home’s.
EPA’s reading of 1.4 pCi/L
Below 2 pCi/L
- Under 20 to 1.9 pCi/L
- 2 to 4consider a fix
- 4 and aboveEPA says fix it
This result is below 2 pCi/L, the level at which EPA says a fix should be considered. Anderson County's median reported result, 2023.
The data
Anderson County, At a glance
Anderson County at a glance
Predicted: EPA radon zone
EPA Zone 1: highest predicted potential
EPA puts all of Anderson County in
USGS geologic potential: High across 69% of the county's area
Predicted: EPA Map of Radon Zones
Measured: tests reported to CDC
Radon tests reported for Anderson County, 2023
| Year | Share of reported tests at or above 4 pCi/L |
|---|---|
| 2022 | 27.1% |
| 2023 | 16.2% |
2023: 16.2%. Across these years the share ran from 16.2% to 27.1%. Each column counts radon tests reported to CDC that year, not homes.
What these figures count
These are the 37 tests reported to CDC for Anderson County over 2023, many from homes being sold or already suspected of a problem: they describe the county's reported tests, not this house.
Measured: CDC tracking data. Figure above: 2023. Measured data period: 2005 to 2023 (every CDC figure on file).
Anderson County, Compared
Anderson County radon figures, compared
Calculated by Radon411Anderson County's 37 reported tests in 2023 had a middle value of 1.4 pCi/L and a maximum of 6.2 pCi/L, and 16.2% reached 4 pCi/L. Tennessee as a whole (70 Tennessee counties, pooled) comes to 24.9%: 8.7 points higher than here.
Among its state's counties it ranks 13th of 15 Tennessee counties with 30 or more tests for the same period. Statewide for the same period, Blount County reported the highest share (50.0%) and Hamilton County the lowest (2.4%).
Below the action level, 21 tests (56.8%) came in under 2 pCi/L, against 49.4% statewide, and 10 tests (27.0%) fell between 2 and 4, against 25.7% statewide. The busiest year on file was 2022, with 144 tests reported; the quietest, 2023, had 37.
EPA's 1993 zone map puts Anderson County in Zone 1, a predicted county average above 4 pCi/L. USGS geology rates 69% of the county's land high radon potential.
Knox County, the one bordering county with a figure for the same period, reported 17.7%.
CDC also counts 5 tests taken after mitigation in Anderson County for the same period: tests in homes where a fix was already in.
Pooled shares: Radon411's sum of CDC's county counts for one period.
Anderson County, Geology
The ground under Anderson County
PredictedUSGS's geologic map splits Anderson County: 68.6% of its land is high radon potential and 31.4% low. The map puts 68.6% of Anderson County in the area it calls Ridge and Valley and 31.4% in Appalachian Plateau. USGS gives the first a radon index of 14, in the high band (12 to 17), and the second 8, in the low band (5 to 8).
| Area | The rock, in USGS's words | Potential | Radon index | Share of land |
|---|---|---|---|---|
| Ridge and Valley | Paleozoic sandstone and cherty dolostone. | High | 14 | 68.6% |
| Appalachian Plateau | Sandstone and shale. | Low | 8 | 31.4% |
Names, descriptions and indexes: U.S. Geological Survey, Geologic Radon Potential Map (2025). Shares: Radon411, from the map cut to the boundary.
Anderson County beside the ground around it
Anderson County has more high-potential ground than Tennessee as a whole: 68.6% of its land against 47.2%. Of the 6 counties that border it, 3 have more high-potential ground, Knox County the most at 100%.
The map rates the ground, not the air in any home.
Local help
Anderson County, Local resources
Radon testing and mitigation in Anderson 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
Anderson County, Questions
Questions about radon in Anderson County
Are radon levels high in Anderson County?
In 2023, 16.2% of the radon tests reported to CDC for Anderson County, Tennessee were at or above 4 pCi/L, and the median reported pre-mitigation result was 1.4 pCi/L. Of 15 Tennessee counties with 30 or more tests for the same period, 12 reported a higher share; pooled, the state comes to 24.9%.
Which counties border Anderson County?
Anderson County borders 6 counties: Campbell County, Knox County, Scott County, Morgan County, Roane County and Union County.
Products
Anderson County, Products
Testing a home in Anderson County
In Anderson County, 16.2% of 37 tests reported to CDC in 2023 reached 4 pCi/L, against 24.9% pooled across Tennessee. In Zone 1 the year-round level in Anderson 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 monitor
Monitor
View Radon Wi-Fi radon monitor with an e-paper display
- C-NRPP 2024/25: Approved
- Battery
- Wi-Fi, Bluetooth
- Screen, app
Method: Alpha spectrometry
Readings: Every 60 minutes
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
Anderson County is in EPA Zone 1, the highest predicted radon potential. Best radon monitors for Zone 1 counties like Anderson County
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Anderson County, Bordering counties
Counties bordering Anderson County
Calculated by Radon411- Radon levels in Morgan CountyEPA zone 3
100.0%at or above 4 pCi/L
Median 23.2 pCi/L · 1 test · 83.8 points above Anderson County
- Radon levels in Campbell CountyEPA zone 3
40.0%at or above 4 pCi/L
Median 2.7 pCi/L · 5 tests · 23.8 points above Anderson County
- Radon levels in Union CountyEPA zone 1
33.3%at or above 4 pCi/L
Median 1.8 pCi/L · 3 tests · 17.1 points above Anderson County
- Radon levels in Roane CountyEPA zone 1
20.0%at or above 4 pCi/L
Median 2.2 pCi/L · 20 tests · 3.8 points above Anderson County
- Radon levels in Knox CountyEPA zone 1
17.7%at or above 4 pCi/L
Median 1.8 pCi/L · 203 tests · 1.5 points above Anderson County
- Radon levels in Scott CountyEPA zone 3
No CDC figure for 2023; its page reads it against its own neighbours.
Anderson County, Cities and towns
Cities and towns in Anderson County
Anderson County is growing: the Census Bureau puts it at 82,066 residents on July 1, 2025, up 6.1% from 77,347 in 2020. That works out to 243 people per square mile of land. Oak Ridge, the largest place on its list (35,395 residents in all), extends beyond Anderson County, so no share of the total is worked out for it. CDC's 37 reported tests for 2023 work out to 0.5 per 1,000 residents (2025 estimate), close to Tennessee's 0.3.
From Oak Ridge to Norris, CDC publishes no figure by town: each reads Anderson County's.
| Place | Residents | Since 2020 | Share of residents |
|---|---|---|---|
| Oak Ridgeextends beyond Anderson County | 35,395 | +11.6% | Counted whole |
| Clinton | 10,466 | +4.3% | 12.8% |
| Oliver Springsextends beyond Anderson County | 3,433 | +4.4% | Counted whole |
| Rocky Topextends beyond Anderson County | 1,681 | +3.0% | Counted whole |
| Norris | 1,621 | +1.6% | 2.0% |
5 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 Anderson County is counted whole, so it has no share.
Anderson County, Homes
Homes in Anderson County
Of Anderson County's 35,570 homes, 71% are detached houses, against 68% across Tennessee; 12% are in buildings of five or more homes. The homes are older than Tennessee's as a whole: half were built before 1977 (1986 for Tennessee), and 31% date from before 1960. 71% 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 | Anderson County | Tennessee |
|---|---|---|
| Housing units | 35,570 | 3,095,472 |
| Detached houses | 71% | 68% |
| In buildings of 5 or more | 12% | 14% |
| Mobile homes | 10% | 8% |
| Built before 1960 | 31% | 18% |
| Built since 2000 | 18% | 29% |
| Middle year built | 1977 | 1986 |
| Owner-occupied | 71% | 67% |
Census Bureau, American Community Survey, 2019 to 2023: estimates from a sample of homes, looser for a small place. Shares by Radon411.