Short-term kit
RA400 short-term liquid scintillation radon test kit, lab fee included
- Lab fee included
Method: Liquid scintillation
In home: 48 to 96 hours
Locations and reports
Radon Levels in Obion County, Tennessee
EPA puts Obion County in Zone 3, its lowest radon zone, and only 3 radon tests from it are on file with CDC (2022). Homes with elevated levels occur in all three zones, so only a test measures yours.
Data checked By Radon411Methodology
Share at 4+ pCi/L
11.1%
22.2 pts below TN
- Obion
- 11.1%
- Tennessee
- 33.3%
36 tests, 2008 to 2017
Median result
1.8pCi/L
Below action level
- Obion
- 1.8 pCi/L
- EPA
- 4.0 pCi/L
Midpoint of the tests, 2008 to 2017
Tests reported
36
75th of 80 by tests
- Obion
- 36
- Davidson
- 5,592
Reported to CDC before any fix, 2008 to 2017
EPA radon zone
Zone 3
Lower potential
- 1
- 2
- Zone 3
1 highest, 3 lowest
EPA predicts under 2 pCi/L indoors
Rank in Tennessee
67 of 80
Lowest quarter
- Obion
- 11.1%
- Jefferson
- 56.8%
By share, of 80 with 30+ tests
Read a result for Obion County
Starts at Obion County's median, 1.8 pCi/L
EPA’s own thresholds; the figures are the area’s, never this home’s.
EPA’s reading of 1.8 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. Obion County's median reported result, 2008 to 2017.
The data
Obion County, At a glance
Obion County at a glance
Predicted: EPA radon zone
EPA Zone 3: lower predicted potential
USGS geologic potential: Low across 100% of the county's area
Predicted: EPA Map of Radon Zones
Measured: tests reported to CDC
Radon tests reported for Obion County, 2022
CDC holds 3 reported tests for Obion County in 2022, with a median of 1.6 pCi/L: too few to describe a county (Radon411 reads a share from 30 tests up). Obion County beside the counties around it is how this page reads it.
What these figures count
Only 3 tests were reported to CDC for Obion County over 2022, 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: 2022. Measured data period: 2005 to 2022 (every CDC figure on file).
Obion County, Compared
Obion County radon figures, compared
Calculated by Radon411Obion County reports fewer high tests than Tennessee overall. 11.1% of its 36 tests over the 2008 to 2017 laboratory totals were at or above 4 pCi/L. That is 22.2 points below the 33.3% pooled from 95 Tennessee counties.
The newest figure, in 2022, counts only 3 tests (0.0% at or above 4 pCi/L), too few to compare, so this reading uses the 36-test figure.
Ordered from highest share down, it comes 67th of 80 Tennessee counties with 30 or more tests for the same period. Nationally, every county with a figure for the same period pools to 35.7%; Obion County sits 24.6 points below it.
Gibson County, the one bordering county with a figure for the same period, reported 5.3%. Zone 3 on EPA's map (predicted average under 2 pCi/L) and a 11.1% share point the same way here.
Half the tests came in under 1.8 pCi/L and half over it; the single highest reached 13.2 pCi/L. The rest split 61.1% under 2 pCi/L and 27.8% from 2 to 4 (Tennessee: 42.4% and 24.3%).
CDC's ten-year totals for Obion County went from 30 tests (2005 to 2014) to 36 (2008 to 2017), the share going from 10.0% to 11.1%.
Pooled shares: Radon411's sum of CDC's county counts for one period.
Obion County, Geology
The ground under Obion County
PredictedUSGS's geologic map puts all of Obion County's mapped land in one class: low radon potential. The map puts 92.4% of Obion County in the area it calls Loess-Covered Coastal Plain and 7.6% in Mississippi Alluvial Plain. USGS gives the first a radon index of 8 and the second 7, both in the low band (5 to 8).
| Area | The rock, in USGS's words | Potential | Radon index | Share of land |
|---|---|---|---|---|
| Loess-Covered Coastal Plain | Cretaceous and younger marine and fluvial sand, clay, and marl covered with loess. | Low | 8 | 92.4% |
| Mississippi Alluvial Plain | Alluvial sand, silt, gravel, and clay. | Low | 7 | 7.6% |
Names, descriptions and indexes: U.S. Geological Survey, Geologic Radon Potential Map (2025). Shares: Radon411, from the map cut to the boundary.
Obion County beside the ground around it
Across Tennessee 47.2% of the land is rated high; none of Obion County's is. None of the 6 counties that border it has any moderate-potential ground either.
The map rates the ground, not the air in any home.
Local help
Obion County, Local resources
Radon testing and mitigation in Obion 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
Obion County, Questions
Questions about radon in Obion County
Are radon levels high in Obion County?
In 2022, 0.0% of the radon tests reported to CDC for Obion 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, 66 reported a higher share; pooled, the state comes to 33.3%.
Which counties border Obion County?
Obion County borders 6 counties: Fulton County, KY, Lake County, TN, Hickman County, KY, Weakley County, TN, Dyer County, TN and Gibson County, TN.
Products
Obion County, Products
Testing a home in Obion County
In Obion County, 11.1% of 36 tests reported to CDC over the 2008 to 2017 laboratory totals reached 4 pCi/L, against 33.3% pooled across Tennessee. Zone 3 is the lowest label, yet homes at or above 4 pCi/L occur in every zone: a short-term kit (2 to 90 days) is the quick first check in Obion County.
Test kits and monitors3
See every kit and monitor
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
MonitorAEGTEST
HOUND-3786 rechargeable radon monitor with a 3.5-inch color screen
- C-NRPP 2024/25: Not included
- Battery
- Alarm
- Screen
Method: Ion chamber
First reading: Within 10 minutes
- See every kit and monitor Test kits and monitors
Test kits and monitors: 1 of 3
Explore
Obion County, Bordering counties
Counties bordering Obion County
Calculated by Radon411- Radon levels in Weakley County, TNEPA zone 3
12.5%at or above 4 pCi/L
Median 1.1 pCi/L · 16 tests · 1.4 points above Obion County
- Radon levels in Gibson County, TNEPA zone 3
5.3%at or above 4 pCi/L
Median 1.0 pCi/L · 57 tests · 5.8 points below Obion County
- Radon levels in Fulton County, KYEPA zone 3
0.0%at or above 4 pCi/L
Median 1.9 pCi/L · 1 test · 11.1 points below Obion County
- Radon levels in Lake County, TNEPA zone 3
0.0%at or above 4 pCi/L
Median 1.0 pCi/L · 7 tests · 11.1 points below Obion County
- Radon levels in Hickman County, KYEPA zone 3
0.0%at or above 4 pCi/L
Median 0.1 pCi/L · 7 tests · 11.1 points below Obion County
- Radon levels in Dyer County, TNEPA zone 3
0.0%at or above 4 pCi/L
Median 1.4 pCi/L · 22 tests · 11.1 points below Obion County
Obion County, Cities and towns
Cities and towns in Obion County
About 30,067 people live in Obion County by the Census Bureau's estimate for July 1, 2025, 712 fewer than in 2020 (−2.3%). That works out to 55 people per square mile of land. Its largest town, Union City, has 10,814 residents, 36.0% of the total. Reported testing is thin here: 36 tests over 2008 to 2017, or 1.2 for every 1,000 residents (2025 estimate), where Tennessee as a whole comes to 4.2.
From Union City to Samburg, CDC publishes no figure by town: each reads Obion County's.
| Place | Residents | Since 2020 | Share of residents |
|---|---|---|---|
| Union City | 10,814 | −3.2% | 36.0% |
| South Fulton | 2,158 | −3.7% | 7.2% |
| Troy | 1,399 | −0.8% | 4.7% |
| Kentonextends beyond Obion County | 1,248 | −2.7% | Counted whole |
| Obion | 958 | −3.5% | 3.2% |
| Trimbleextends beyond Obion County | 533 | −2.0% | Counted whole |
| Hornbeak | 503 | −1.0% | 1.7% |
| Woodland Mills | 334 | −2.3% | 1.1% |
| Rives | 244 | −1.2% | 0.8% |
| Samburg | 198 | −4.8% | 0.7% |
10 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 Obion County is counted whole, so it has no share.
Obion County, Homes
Homes in Obion County
Obion County is a place of houses on their own lots: 75% of its 14,343 homes are detached single-family houses, against 68% across Tennessee. The homes are older than Tennessee's as a whole: half were built before 1975 (1986 for Tennessee), and 25% date from before 1960. 67% 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 | Obion County | Tennessee |
|---|---|---|
| Housing units | 14,343 | 3,095,472 |
| Detached houses | 75% | 68% |
| In buildings of 5 or more | 4% | 14% |
| Mobile homes | 12% | 8% |
| Built before 1960 | 25% | 18% |
| Built since 2000 | 15% | 29% |
| Middle year built | 1975 | 1986 |
| Owner-occupied | 67% | 67% |
Census Bureau, American Community Survey, 2019 to 2023: estimates from a sample of homes, looser for a small place. Shares by Radon411.