Short-term kitKidde
442020 short-term charcoal radon test kit
- Lab fee included
Method: Charcoal
In home: 3 days
Locations and reports
Radon Levels in Reynolds County, Missouri
EPA puts Reynolds County in Zone 2, its middle radon zone, and only 1 radon test from it is on file with CDC (2022). Homes with elevated levels occur in all three zones, so only a test measures yours.
Data checked By Radon411Methodology
Nearest county
41.1%
St. Francois County, 41 miles
- St. Francois
- 41.1%
- Missouri
- 30.6%
Share at 4+ pCi/L, 146 tests, 2008 to 2017
Ground above low
100.0%
5.8 pts above Missouri
- Reynolds
- 100.0%
- Missouri
- 94.2%
Share of land USGS rates moderate or high potential
Tests reported
3
Too few for a share
- Reynolds
- 3
- Needed
- 30
2008 to 2017, laboratory
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 Reynolds 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
Reynolds County, At a glance
Reynolds County at a glance
Predicted: EPA radon zone
EPA Zone 2: moderate predicted potential
Reynolds County is a
USGS geologic potential: Moderate across 85% of the county's area
Predicted: EPA Map of Radon Zones
Measured: tests reported to CDC
Radon tests reported for Reynolds County, 2022
| Year | Share of reported tests at or above 4 pCi/L |
|---|---|
| 2017 | 50.0% |
| 2019 | 100.0% |
| 2022 | 0.0% |
2022: 0.0%. 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 Reynolds 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).
Reynolds County, Compared
Reynolds County radon figures, compared
Calculated by Radon411CDC's largest figure for Reynolds County rests on 3 tests over the 2008 to 2017 laboratory totals, 1 of them at or above 4 pCi/L, so each test moves its share by 33.3 points and no rank or comparison is drawn from it. Results reached as high as 10.1 pCi/L, with a middle value of 2.2 pCi/L.
The nearest counties with a figure are St. Francois County (41 miles away) at 41.1%, Washington County (42 miles away) at 26.3% and Crawford County (46 miles away) at 14.7%. 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 Reynolds County in Zone 2, its middle label: a predicted county average between 2 and 4 pCi/L. USGS geology rates 85% of the county's land moderate radon potential.
Pooled shares: Radon411's sum of CDC's county counts for one period.
Reynolds County, Geology
The ground under Reynolds County
PredictedMost of the ground under Reynolds County is one class on USGS's geologic map: 85.5% of its land is moderate radon potential, with 14.5% high. The map puts 85.5% of Reynolds County in the area it calls Salem Plateau and 14.5% in St. Francois Mountains. USGS gives the first a radon index of 11, in the moderate band (9 to 11), and the second 13, in the high band (12 to 17).
| Area | The rock, in USGS's words | Potential | Radon index | Share of land |
|---|---|---|---|---|
| Salem Plateau | Ordovician dolomite, sandstone, limestone, and shale. | Moderate | 11 | 85.5% |
| St. Francois Mountains | Granitic and volcanic rocks. Some soils have high uranium concentrations. | High | 13 | 14.5% |
Names, descriptions and indexes: U.S. Geological Survey, Geologic Radon Potential Map (2025). Shares: Radon411, from the map cut to the boundary.
Reynolds County beside the ground around it
On high-potential ground Reynolds County is close to Missouri as a whole: 14.5% of its land against 8.2%. Of the 5 counties that border it, 1 has more high-potential ground, Iron County the most at 85.3%.
The map rates the ground, not the air in any home.
Local help
Reynolds County, Local resources
Radon testing and mitigation in Reynolds 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
Reynolds County, Questions
Questions about radon in Reynolds County
Are radon levels high in Reynolds County?
In 2022, 0.0% of the radon tests reported to CDC for Reynolds County, Missouri were at or above 4 pCi/L, and the median reported pre-mitigation result was 2.1 pCi/L. Of the 8 nearest counties with a figure, within 65 miles, the share of tests at or above 4 pCi/L runs from 14.7% to 45.7%.
Which counties border Reynolds County?
Reynolds County borders 5 counties: Iron County, Shannon County, Carter County, Wayne County and Dent County.
Products
Reynolds County, Products
Testing a home in Reynolds County
No CDC figure names Reynolds County; the nearest county with one, St. Francois County (41 miles away), reported 41.1% 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 Reynolds County; a long-term test tells the year-round average.
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
MonitorSafetySiren
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
- See every kit and monitor Test kits and monitors
Test kits and monitors: 1 of 3
Explore
Reynolds County, Bordering counties
Counties bordering Reynolds County
Calculated by Radon411- Radon levels in Iron CountyEPA zone 1
50.0%at or above 4 pCi/L
Median 3.5 pCi/L · 14 tests
- Radon levels in Dent CountyEPA zone 2
35.7%at or above 4 pCi/L
Median 3.0 pCi/L · 14 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 Carter CountyEPA zone 2
25.0%at or above 4 pCi/L
Median 2.8 pCi/L · 4 tests
- Radon levels in Wayne CountyEPA zone 2
23.5%at or above 4 pCi/L
Median 1.9 pCi/L · 17 tests
Reynolds County, Cities and towns
Cities and towns in Reynolds County
About 5,992 people live in Reynolds County by the Census Bureau's estimate for July 1, 2025, 85 fewer than in 2020 (−1.4%). Spread over its land, that is 7.4 people to the square mile. No town dominates: Ellington, the largest, has 777 residents, 13.0% of the total. Reported testing is thin here: 3 tests over 2008 to 2017, or 0.5 for every 1,000 residents (2025 estimate), where Missouri as a whole comes to 9.3.
From Ellington to Centerville, CDC publishes no figure by town: each reads Reynolds County's.
| Place | Residents | Since 2020 | Share of residents |
|---|---|---|---|
| Ellington | 777 | −1.9% | 13.0% |
| Bunkerextends beyond Reynolds County | 297 | −0.7% | Counted whole |
| Centerville | 165 | −1.8% | 2.8% |
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). A place that extends beyond Reynolds County is counted whole, so it has no share.
Reynolds County, Homes
Homes in Reynolds County
Reynolds County is a place of houses on their own lots: 76% of its 3,468 homes are detached single-family houses, against 70% across Missouri. Half of its homes were built before 1975, close to Missouri's 1978: 26% date from before 1960 and 16% from 2000 or later. Owners live in 81% of the occupied homes (Missouri: 68%), so for most households a test and a fix are their own to order.
| Homes | Reynolds County | Missouri |
|---|---|---|
| Housing units | 3,468 | 2,809,501 |
| Detached houses | 76% | 70% |
| In buildings of 5 or more | 2% | 13% |
| Mobile homes | 20% | 5% |
| Built before 1960 | 26% | 28% |
| Built since 2000 | 16% | 21% |
| Middle year built | 1975 | 1978 |
| Owner-occupied | 81% | 68% |
Census Bureau, American Community Survey, 2019 to 2023: estimates from a sample of homes, looser for a small place. Shares by Radon411.