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 Calloway County, Kentucky
EPA puts Calloway County in Zone 3, its lowest radon zone, and only 27 radon tests from it are on file with CDC (2008 to 2017, laboratory totals). Homes with elevated levels occur in all three zones, so only a test measures yours.
Data checked By Radon411Methodology
Highest bordering
26.3%
Stewart County
- Stewart
- 26.3%
- Marshall
- 10.6%
4 of 5 neighbours have 30+ tests, 2008 to 2017
Nearest county
10.6%
Marshall County, 18 miles
- Marshall
- 10.6%
- Kentucky
- 43.7%
Share at 4+ pCi/L, 85 tests, 2008 to 2017
Ground above low
21.8%
72.5 pts below Kentucky
- Calloway
- 21.8%
- Kentucky
- 94.3%
Share of land USGS rates moderate or high potential
Tests reported
27
Too few for a share
- Calloway
- 27
- Needed
- 30
2008 to 2017, laboratory
EPA radon zone
Zone 3
Lower potential
- 1
- 2
- Zone 3
1 highest, 3 lowest
EPA predicts under 2 pCi/L indoors
Read a result for Calloway 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
Calloway County, At a glance
Calloway County at a glance
Predicted: EPA radon zone
EPA Zone 3: lower predicted potential
USGS geologic potential: Low across 78% of the county's area
Predicted: EPA Map of Radon Zones
Measured: tests reported to CDC
Radon tests reported for Calloway County, 2008 to 2017, laboratory
CDC holds 27 reported tests for Calloway County over the 2008 to 2017 laboratory totals, with a median of 2.4 pCi/L: too few to describe a county (Radon411 reads a share from 30 tests up). Calloway County beside the counties around it is how this page reads it.
What these figures count
Only 27 tests were reported to CDC for Calloway County over 2008 to 2017 (laboratory totals), 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: 2008 to 2017, laboratory. Measured data period: 2005 to 2017 (every CDC figure on file).
Calloway County, Compared
Calloway County radon figures, compared
Calculated by Radon411CDC's largest figure for Calloway County rests on 27 tests over the 2008 to 2017 laboratory totals, 6 of them at or above 4 pCi/L, so each test moves its share by 3.7 points and no rank or comparison is drawn from it. Results reached as high as 8.9 pCi/L, with a middle value of 2.4 pCi/L.
Of the counties bordering it, 4 have a figure over the 2008 to 2017 laboratory totals: Stewart County, TN reported the largest share at or above 4 pCi/L, 26.3%, and Marshall County the smallest, 10.6%, with Trigg County at 22.2% and Henry County, TN at 16.7% between. Farther out, Christian County (47 miles away) at 36.1%, Hopkins County (62 miles away) at 9.5% and Todd County (62 miles away) at 17.7% have figures too. Pooled across 120 Kentucky counties, 43.7% of reported tests reached that level; across every county in the country with a figure, 35.7%.
Statewide for the same period, Meade County reported the highest share (68.4%) and Hopkins County the lowest (9.5%). EPA's 1993 map puts Calloway County in Zone 3, its lowest label: a predicted county average under 2 pCi/L. USGS geology rates 78% of the county's land low radon potential.
Pooled shares: Radon411's sum of CDC's county counts for one period.
Calloway County, Geology
The ground under Calloway County
PredictedMost of the ground under Calloway County is one class on USGS's geologic map: 78.2% of its land is low radon potential, with 2.2% high and 19.6% moderate. The map puts 77.9% of Calloway County in the area it calls Jackson Purchase and 14.8% in Mississippian Plateau, with 2 smaller areas beside them. USGS gives the first a radon index of 6, in the low band (5 to 8), and the second 11, in the moderate band (9 to 11).
| Area | The rock, in USGS's words | Potential | Radon index | Share of land |
|---|---|---|---|---|
| Jackson Purchase | Cretaceous and Tertiary marine and continental gravels, sands, silts, and clays, overlain by alluvium and loess. | Low | 6 | 77.9% |
| Mississippian Plateau | Mississippian marine limestones, dolomites, marine sandstones, siltstones, and shales. | Moderate | 11 | 14.8% |
| East Coastal Plain | Cretaceous and younger marine and fluvial sand, clay, and marl. | Moderate | 9 | 4.7% |
| Cherty Highland | Cherty dolostone. | High | 12 | 2.2% |
Names, descriptions and indexes: U.S. Geological Survey, Geologic Radon Potential Map (2025). Shares: Radon411, from the map cut to the boundary.
Calloway County beside the ground around it
Kentucky as a whole has more high-potential ground than Calloway County: 18.2% of its land, against 2.2% here. Of the 5 counties that border it, 2 have more high-potential ground, Stewart County, TN the most at 17.3%.
The map rates the ground, not the air in any home.
Local help
Calloway County, Local resources
Radon testing and mitigation in Calloway County
- Kentucky's radon programKentucky Board of Radon SafetyKentucky's radon program answers questions about testing, mitigation and the rules in Kentucky.Visit the program’s page(opens in a new tab)
- Free and low-cost kitsAsk the program whether it has free or discounted kits, or compare kits you can buy.
- Compare kits
- Professionals in Kentucky8 professionals are listed in Kentucky.
What Kentucky's program says
- Phone
- 502-782-2782
- Radon@ky.gov
What it means
Calloway County, Questions
Questions about radon in Calloway County
Are radon levels high in Calloway County?
Over the 2008 to 2017 laboratory totals, 22.2% of the radon tests reported to CDC for Calloway County, Kentucky were at or above 4 pCi/L, and the median reported pre-mitigation result was 2.4 pCi/L. Of the counties bordering it, 4 have a figure over the 2008 to 2017 laboratory totals: Stewart County, TN reported the largest share at or above 4 pCi/L, 26.3%, and Marshall County the smallest, 10.6%, with Trigg County at 22.2% and Henry County, TN at 16.7% between.
Which counties border Calloway County?
Calloway County borders 5 counties: Henry County, TN, Marshall County, KY, Graves County, KY, Trigg County, KY and Stewart County, TN.
Products
Calloway County, Products
Testing a home in Calloway County
No CDC figure names Calloway County; the nearest county with one, Marshall County (18 miles away), reported 10.6% 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. 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 Calloway County.
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
Calloway County, Bordering counties
Counties bordering Calloway County
Calculated by Radon411- Radon levels in Stewart County, TNEPA zone 2
26.3%at or above 4 pCi/L
Median 2.1 pCi/L · 95 tests
- Radon levels in Trigg County, KYEPA zone 2
22.2%at or above 4 pCi/L
Median 2.4 pCi/L · 45 tests
- Radon levels in Henry County, TNEPA zone 3
16.7%at or above 4 pCi/L
Median 1.6 pCi/L · 60 tests
- Radon levels in Marshall County, KYEPA zone 3
10.6%at or above 4 pCi/L
Median 1.5 pCi/L · 85 tests
- Radon levels in Graves County, KYEPA zone 3
8.3%at or above 4 pCi/L
Median 1.5 pCi/L · 24 tests
Calloway County, Cities and towns
Cities and towns in Calloway County
The Census Bureau estimates 39,421 residents in Calloway County for July 1, 2025, 1,826 more than in 2020 (+4.9%). That works out to 102 people per square mile of land. Its largest town, Murray, has 18,964 residents, 48.1% of the total. Together its 2 incorporated places hold 49.1% of those residents; the other 50.9% live outside any of them. Reported testing is thin here: 27 tests over 2008 to 2017, or 0.7 for every 1,000 residents (2025 estimate), where Kentucky as a whole comes to 6.3.
From Murray to Hazel, CDC publishes no figure by town: each reads Calloway County's.
| Place | Residents | Since 2020 | Share of residents |
|---|---|---|---|
| Murray | 18,964 | +6.7% | 48.1% |
| Hazel | 408 | +3.0% | 1.0% |
2 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).
Calloway County, Homes
Homes in Calloway County
Of Calloway County's 18,034 homes, 64% are detached houses, against 68% across Kentucky; 14% are mobile homes. Half of its homes were built before 1985, close to Kentucky's 1982: 17% date from before 1960 and 25% from 2000 or later. 64% of occupied homes are lived in by their owner (Kentucky: 68%); in the rest a tenant can run a test, but a fix is the landlord's to make.
| Homes | Calloway County | Kentucky |
|---|---|---|
| Housing units | 18,034 | 2,010,655 |
| Detached houses | 64% | 68% |
| In buildings of 5 or more | 9% | 12% |
| Mobile homes | 14% | 11% |
| Built before 1960 | 17% | 22% |
| Built since 2000 | 25% | 24% |
| Middle year built | 1985 | 1982 |
| 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.