Short-term kit
Air Chek Short-Term radon test kit you hang, lab fee included
- Lab fee included
In home: 72 to 168 hours
Locations and reports
Radon Levels in Carter County, Missouri
EPA puts Carter County in Zone 2, its middle radon zone, and only 1 radon test from it is on file with CDC (2023). Homes with elevated levels occur in all three zones, so only a test measures yours.
Data checked By Radon411Methodology
Highest bordering
21.2%
Butler County
- Butler
- 21.2%
1 of 6 neighbours have 30+ tests, 2008 to 2017
Nearest county
21.2%
Butler County, 34 miles
- Butler
- 21.2%
- Missouri
- 30.6%
Share at 4+ pCi/L, 33 tests, 2008 to 2017
Ground above low
100.0%
5.8 pts above Missouri
- Carter
- 100.0%
- Missouri
- 94.2%
Share of land USGS rates moderate or high potential
Tests reported
15
Too few for a share
- Carter
- 15
- Needed
- 30
2017
EPA radon zone
Zone 2
Moderate potential
- 1
- Zone 2
- 3
1 highest, 3 lowest
EPA predicts 2 to 4 pCi/L indoors
Read a result for Carter County
Starts at EPA's action level
EPA’s own thresholds; the figures are the area’s, never this home’s.
EPA’s reading of 4.0 pCi/L
At or above 4 pCi/L
- Under 20 to 1.9 pCi/L
- 2 to 4consider a fix
- 4 and aboveEPA says fix it
This result is at or above 4 pCi/L. EPA recommends fixing a home when the radon level is 4 pCi/L or higher.
The data
Carter County, At a glance
Carter County at a glance
Predicted: EPA radon zone
EPA Zone 2: moderate predicted potential
Carter County is a
USGS geologic potential: Moderate across 100% of the county's area
Predicted: EPA Map of Radon Zones
Measured: tests reported to CDC
Radon tests reported for Carter County, 2023
| Year | Share of reported tests at or above 4 pCi/L |
|---|---|
| 2014 | 100.0% |
| 2015 | 0.0% |
| 2016 | 72.7% |
| 2017 | 60.0% |
| 2018 | 0.0% |
| 2019 | 100.0% |
| 2021 | 100.0% |
| 2022 | 100.0% |
| 2023 | 100.0% |
2023: 100.0%. Across these years the share ran from 0.0% to 100.0%. Each column counts radon tests reported to CDC that year, not homes.
What these figures count
Only 1 test was reported to CDC for Carter 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).
Carter County, Compared
Carter County radon figures, compared
Calculated by Radon411CDC's largest figure for Carter County rests on 15 tests in 2017, 9 of them at or above 4 pCi/L, so each test moves its share by 6.7 points and no rank or comparison is drawn from it. Results reached as high as 30.5 pCi/L, with a middle value of 6.2 pCi/L.
Butler County, the one bordering county with a figure over the 2008 to 2017 laboratory totals, reported 21.2% of its tests at or above 4 pCi/L. Farther out, Howell County (52 miles away) at 45.7%, Texas County (61 miles away) at 19.3% and St. Francois County (66 miles away) at 41.1% have figures too. Pooled across 115 Missouri counties, 30.6% of reported tests reached that level; across every county in the country with a figure, 35.7%.
Statewide for the same period, Atchison County reported the highest share (69.9%) and Vernon County the lowest (8.8%). EPA's 1993 map puts Carter County in Zone 2, its middle label: a predicted county average between 2 and 4 pCi/L. USGS geology rates 100% of the county's land moderate radon potential.
Pooled shares: Radon411's sum of CDC's county counts for one period.
Carter County, Geology
The ground under Carter County
PredictedUSGS's geologic map puts all of Carter County's mapped land in one class: moderate radon potential. All of it lies in the area the map calls Salem Plateau, to which USGS gives a radon index of 11, in the moderate band (9 to 11).
| Area | The rock, in USGS's words | Potential | Radon index | Share of land |
|---|---|---|---|---|
| Salem Plateau | Ordovician dolomite, sandstone, limestone, and shale. | Moderate | 11 | 100% |
Names, descriptions and indexes: U.S. Geological Survey, Geologic Radon Potential Map (2025). Shares: Radon411, from the map cut to the boundary.
Carter County beside the ground around it
Across Missouri 8.2% of the land is rated high; none of Carter County's is. Of the 6 counties that border it, 2 have more high-potential ground, Reynolds County the most at 14.5%.
The map rates the ground, not the air in any home.
Local help
Carter County, Local resources
Radon testing and mitigation in Carter County
- Missouri Radon ProgramMissouri Radon Program, run by Missouri Department of Health and Senior Services, offers free or discounted test kits, and answers questions about testing and mitigation in Missouri.Visit the program’s page(opens in a new tab)
- Free and low-cost kitsThe program says:
Free radon test kits are available for Missouri residents (limit one per household).
- Compare kits
- Professionals in Missouri27 professionals are listed in Missouri.
What Missouri's program says
- Phone
- 573-751-6102
- radon@health.mo.gov
What it means
Carter County, Questions
Questions about radon in Carter County
Are radon levels high in Carter County?
In 2023, 100.0% of the radon tests reported to CDC for Carter County, Missouri were at or above 4 pCi/L, and the median reported pre-mitigation result was 7.6 pCi/L. Butler County, the one bordering county with a figure over the 2008 to 2017 laboratory totals, reported 21.2% of its tests at or above 4 pCi/L.
Which counties border Carter County?
Carter County borders 6 counties: Ripley County, Shannon County, Reynolds County, Wayne County, Oregon County and Butler County.
Products
Carter County, Products
Testing a home in Carter County
No CDC figure names Carter County; the nearest county with one, Butler County (34 miles away), reported 21.2% of its tests at or above 4 pCi/L over the 2008 to 2017 laboratory totals, the only reading nearby until a test of this home. In Zone 2 a short-term kit (2 to 90 days) is the quick first check in Carter County; a long-term test tells the year-round average.
Test kits and monitors3
See every kit and monitor
Long-term kit
RL116 long-term radon test kit
- Lab fee extra
Method: Alpha track
In home: 90 days to 12 months
Monitor
RM-63Pro rechargeable radon monitor with a touchscreen
- C-NRPP 2024/25: Not included
- Battery
- Alarm
- Screen
Method: Semiconductor sensor
- See every kit and monitor Test kits and monitors
Test kits and monitors: 1 of 3
Explore
Carter County, Bordering counties
Counties bordering Carter County
Calculated by Radon411- Radon levels in Reynolds CountyEPA zone 2
33.3%at or above 4 pCi/L
Median 2.2 pCi/L · 3 tests
- Radon levels in Oregon CountyEPA zone 2
33.3%at or above 4 pCi/L
Median 2.0 pCi/L · 3 tests
- Radon levels in Ripley CountyEPA zone 2
30.0%at or above 4 pCi/L
Median 3.0 pCi/L · 10 tests
- Radon levels in Shannon CountyEPA zone 2
26.3%at or above 4 pCi/L
Median 1.3 pCi/L · 19 tests
- Radon levels in Wayne CountyEPA zone 2
23.5%at or above 4 pCi/L
Median 1.9 pCi/L · 17 tests
- Radon levels in Butler CountyEPA zone 3
21.2%at or above 4 pCi/L
Median 1.9 pCi/L · 33 tests
Carter County, Cities and towns
Cities and towns in Carter County
The Census Bureau estimates 5,418 residents in Carter County for July 1, 2025, 217 more than in 2020 (+4.2%). That works out to 11 people per square mile of land. No town dominates: Van Buren, the largest, has 792 residents, 14.6% of the total. Together its 3 incorporated places hold 26.7% of those residents; the other 73.3% live outside any of them. Testing is reported here more often than across the state: CDC's 15 reported tests for 2017 come to 2.8 for every 1,000 residents (2025 estimate), against 0.4 for Missouri.
From Van Buren to Grandin, CDC publishes no figure by town: each reads Carter County's.
| Place | Residents | Since 2020 | Share of residents |
|---|---|---|---|
| Van Buren | 792 | +5.3% | 14.6% |
| Ellsinore | 421 | +3.4% | 7.8% |
| Grandin | 233 | +4.5% | 4.3% |
3 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).
Carter County, Homes
Homes in Carter County
Of Carter County's 2,692 homes, 70% are detached houses, against 70% across Missouri; 22% are mobile homes. Half of its homes were built before 1984, close to Missouri's 1978: 10% date from before 1960 and 26% from 2000 or later. 64% of occupied homes are lived in by their owner (Missouri: 68%); in the rest a tenant can run a test, but a fix is the landlord's to make.
| Homes | Carter County | Missouri |
|---|---|---|
| Housing units | 2,692 | 2,809,501 |
| Detached houses | 70% | 70% |
| In buildings of 5 or more | 1% | 13% |
| Mobile homes | 22% | 5% |
| Built before 1960 | 10% | 28% |
| Built since 2000 | 26% | 21% |
| Middle year built | 1984 | 1978 |
| Owner-occupied | 64% | 68% |
Census Bureau, American Community Survey, 2019 to 2023: estimates from a sample of homes, looser for a small place. Shares by Radon411.