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
Locations and reports
Radon Levels in Washington County, Kentucky
EPA puts Washington County in Zone 2, its middle radon zone, and 27.3% of its 44 reported radon tests (2008 to 2017, laboratory totals) 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
27.3%
16.4 pts below KY
- Washington
- 27.3%
- Kentucky
- 43.7%
44 tests, 2008 to 2017
Median result
2.4pCi/L
Below action level
- Washington
- 2.4 pCi/L
- EPA
- 4.0 pCi/L
Midpoint of the tests, 2008 to 2017
Tests reported
44
55th of 69 by tests
- Washington
- 44
- Jefferson
- 6,590
Reported to CDC before any fix, 2008 to 2017
EPA radon zone
Zone 2
Moderate potential
- 1
- Zone 2
- 3
1 highest, 3 lowest
EPA predicts 2 to 4 pCi/L indoors
Rank in Kentucky
49 of 69
Middle half
- Washington
- 27.3%
- Meade
- 68.4%
By share, of 69 with 30+ tests
Read a result for Washington County
Starts at Washington County's median, 2.4 pCi/L
EPA’s own thresholds; the figures are the area’s, never this home’s.
EPA’s reading of 2.4 pCi/L
Between 2 and 4 pCi/L
- Under 20 to 1.9 pCi/L
- 2 to 4consider a fix
- 4 and aboveEPA says fix it
This result is between 2 and 4 pCi/L. EPA recommends considering a fix when the level is between 2 and 4 pCi/L. Washington County's median reported result, 2008 to 2017.
The data
Washington County, At a glance
Washington County at a glance
Predicted: EPA radon zone
EPA Zone 2: moderate predicted potential
Washington 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 Washington County, 2008 to 2017, laboratory
Under 2 pCi/L: 43%2 to 4 pCi/L: 30%4 pCi/L and above: 27%
Of 44 pre-mitigation tests reported to CDC, not homes in this area.
| Result band | Tests Measured | Share Measured |
|---|---|---|
| Under 2 pCi/L | 19 | 43.2% |
| 2 to 4 pCi/L | 13 | 29.5% |
| 4 pCi/L and above | 12 | 27.3% |
What these figures count
These are the 44 tests reported to CDC for Washington County over 2008 to 2017 (laboratory totals), 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: 2008 to 2017, laboratory. Measured data period: 2005 to 2017 (every CDC figure on file).
Washington County, Compared
Washington County radon figures, compared
Calculated by Radon411Washington County's 44 reported tests over the 2008 to 2017 laboratory totals had a middle value of 2.4 pCi/L and a maximum of 14.6 pCi/L, and 27.3% reached 4 pCi/L. Kentucky as a whole (120 Kentucky counties, pooled) comes to 43.7%: 16.4 points higher than here.
Among its state's counties it ranks 49th of 69 Kentucky counties with 30 or more tests for the same period. Statewide for the same period, Meade County reported the highest share (68.4%) and Hopkins County the lowest (9.5%).
Below the action level, 19 tests (43.2%) came in under 2 pCi/L, against 33.2% statewide, and 13 tests (29.5%) fell between 2 and 4, against 23.1% statewide. CDC's ten-year totals for Washington County went from 45 tests (2005 to 2014) to 44 (2008 to 2017), the share going from 35.6% to 27.3%.
EPA's 1993 zone map puts Washington County in Zone 2, a predicted county average between 2 and 4 pCi/L. USGS geology rates 100% of the county's land moderate radon potential.
Next door, the shares run from 25.2% in Anderson County to 66.1% in Nelson County, with Anderson County below Washington County.
CDC also counts 6 tests taken after mitigation in Washington 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.
Washington County, Geology
The ground under Washington County
PredictedUSGS's geologic map puts all of Washington County's mapped land in one class: moderate radon potential. All of it lies in the area the map calls Outer Bluegrass, 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 |
|---|---|---|---|---|
| Outer Bluegrass | Ordovician-Devonian 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.
Washington County beside the ground around it
Across Kentucky 18.2% of the land is rated high; none of Washington County's is. Every one of the 5 counties that border it has more high-potential ground, Marion County the most at 67.7%.
The map rates the ground, not the air in any home.
Local help
Washington County, Local resources
Radon testing and mitigation in Washington 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
Washington County, Questions
Questions about radon in Washington County
Are radon levels high in Washington County?
Over the 2008 to 2017 laboratory totals, 27.3% of the radon tests reported to CDC for Washington County, Kentucky were at or above 4 pCi/L, and the median reported pre-mitigation result was 2.4 pCi/L. Of 69 Kentucky counties with 30 or more tests for the same period, 48 reported a higher share; pooled, the state comes to 43.7%.
Which counties border Washington County?
Washington County borders 5 counties: Marion County, Mercer County, Nelson County, Anderson County and Boyle County.
Products
Washington County, Products
Testing a home in Washington County
In Washington County, 27.3% of 44 tests reported to CDC over the 2008 to 2017 laboratory totals reached 4 pCi/L, against 43.7% pooled across Kentucky. In Zone 2 a short-term kit (2 to 90 days) is the quick first check in Washington 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
MonitorINKBIRD
INK-RD3 battery radon monitor with an e-ink screen
- C-NRPP 2024/25: Not included
- Battery
- Screen
First reading: Within 24 hours
- See every kit and monitor Test kits and monitors
Test kits and monitors: 1 of 3
Explore
Washington County, Bordering counties
Counties bordering Washington County
Calculated by Radon411- Radon levels in Nelson CountyEPA zone 1
66.1%at or above 4 pCi/L
Median 6.3 pCi/L · 304 tests · 38.8 points above Washington County
- Radon levels in Boyle CountyEPA zone 1
53.9%at or above 4 pCi/L
Median 4.4 pCi/L · 492 tests · 26.6 points above Washington County
- Radon levels in Marion CountyEPA zone 1
48.6%at or above 4 pCi/L
Median 3.9 pCi/L · 177 tests · 21.3 points above Washington County
- Radon levels in Mercer CountyEPA zone 1
38.2%at or above 4 pCi/L
Median 2.7 pCi/L · 288 tests · 10.9 points above Washington County
- Radon levels in Anderson CountyEPA zone 2
25.2%at or above 4 pCi/L
Median 2.2 pCi/L · 226 tests · 2.1 points below Washington County
Washington County, Cities and towns
Cities and towns in Washington County
The Census Bureau estimates 12,368 residents in Washington County for July 1, 2025, 326 more than in 2020 (+2.7%). That works out to 42 people per square mile of land. Its largest town, Springfield, has 3,033 residents, 24.5% of the total. Together its 3 incorporated places hold 28.6% of those residents; the other 71.4% live outside any of them. Reported testing is thin here: 44 tests over 2008 to 2017, or 3.6 for every 1,000 residents (2025 estimate), where Kentucky as a whole comes to 6.3.
From Springfield to Mackville, CDC publishes no figure by town: each reads Washington County's.
| Place | Residents | Since 2020 | Share of residents |
|---|---|---|---|
| Springfield | 3,033 | +5.8% | 24.5% |
| Willisburg | 303 | +1.0% | 2.4% |
| Mackville | 207 | +1.5% | 1.7% |
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).
Washington County, Homes
Homes in Washington County
Washington County is a place of houses on their own lots: 79% of its 5,222 homes are detached single-family houses, against 68% across Kentucky. Half of its homes were built before 1983, close to Kentucky's 1982: 24% date from before 1960 and 28% from 2000 or later. Owners live in 78% of the occupied homes (Kentucky: 68%), so for most households a test and a fix are their own to order.
| Homes | Washington County | Kentucky |
|---|---|---|
| Housing units | 5,222 | 2,010,655 |
| Detached houses | 79% | 68% |
| In buildings of 5 or more | 4% | 12% |
| Mobile homes | 12% | 11% |
| Built before 1960 | 24% | 22% |
| Built since 2000 | 28% | 24% |
| Middle year built | 1983 | 1982 |
| Owner-occupied | 78% | 68% |
Census Bureau, American Community Survey, 2019 to 2023: estimates from a sample of homes, looser for a small place. Shares by Radon411.