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
Locations and reports
Radon Levels in Robertson County, Kentucky
EPA puts Robertson County in Zone 1, its highest radon zone, and only 4 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
46.8%
Harrison County
- Harrison
- 46.8%
- Mason
- 25.0%
2 of 5 neighbours have 30+ tests, 2008 to 2017
Nearest county
25.0%
Mason County, 13 miles
- Mason
- 25.0%
- Kentucky
- 43.7%
Share at 4+ pCi/L, 32 tests, 2008 to 2017
Ground above low
100.0%
5.7 pts above Kentucky
- Robertson
- 100.0%
- Kentucky
- 94.3%
Share of land USGS rates moderate or high potential
Tests reported
4
Too few for a share
- Robertson
- 4
- Needed
- 30
2008 to 2017, laboratory
EPA radon zone
Zone 1
Highest potential
- Zone 1
- 2
- 3
1 highest, 3 lowest
EPA predicts over 4 pCi/L indoors
Read a result for Robertson 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
Robertson County, At a glance
Robertson County at a glance
Predicted: EPA radon zone
EPA Zone 1: highest predicted potential
EPA puts all of Robertson County in
USGS geologic potential: Moderate across 87% of the county's area
Predicted: EPA Map of Radon Zones
Measured: tests reported to CDC
Radon tests reported for Robertson County, 2008 to 2017, laboratory
CDC holds 4 reported tests for Robertson County over the 2008 to 2017 laboratory totals, with a median of 1.1 pCi/L: too few to describe a county (Radon411 reads a share from 30 tests up). Robertson County beside the counties around it is how this page reads it.
What these figures count
Only 4 tests were reported to CDC for Robertson 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).
Robertson County, Compared
Robertson County radon figures, compared
Calculated by Radon411CDC's largest figure for Robertson County rests on 4 tests over the 2008 to 2017 laboratory totals, 1 of them at or above 4 pCi/L, so each test moves its share by 25.0 points and no rank or comparison is drawn from it. Results reached as high as 5.0 pCi/L, with a middle value of 1.1 pCi/L.
Of the counties bordering it, 2 have a figure over the 2008 to 2017 laboratory totals: Harrison County reported the largest share at or above 4 pCi/L, 46.8%, and Mason County the smallest, 25.0%. Farther out, Pendleton County (21 miles away) at 26.5%, Bourbon County (23 miles away) at 53.5% and Grant County (32 miles away) at 33.3% 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 Robertson County in Zone 1, the map's highest label: a predicted county average above 4 pCi/L. USGS geology rates 87% of the county's land moderate radon potential.
Pooled shares: Radon411's sum of CDC's county counts for one period.
Robertson County, Geology
The ground under Robertson County
PredictedMost of the ground under Robertson County is one class on USGS's geologic map: 86.9% of its land is moderate radon potential, with 13.1% high. The map puts 86.9% of Robertson County in the area it calls Outer Bluegrass and 13.1% in Inner Bluegrass. 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 |
|---|---|---|---|---|
| Outer Bluegrass | Ordovician-Devonian limestone and shale. | Moderate | 11 | 86.9% |
| Inner Bluegrass | Ordovician limestones, dolomites and shales. | High | 13 | 13.1% |
Names, descriptions and indexes: U.S. Geological Survey, Geologic Radon Potential Map (2025). Shares: Radon411, from the map cut to the boundary.
Robertson County beside the ground around it
On high-potential ground Robertson County is close to Kentucky as a whole: 13.1% of its land against 18.2%. Of the 5 counties that border it, 2 have more high-potential ground, Fleming County the most at 45.0%.
The map rates the ground, not the air in any home.
Local help
Robertson County, Local resources
Radon testing and mitigation in Robertson 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
Robertson County, Questions
Questions about radon in Robertson County
Are radon levels high in Robertson County?
Over the 2008 to 2017 laboratory totals, 25.0% of the radon tests reported to CDC for Robertson County, Kentucky were at or above 4 pCi/L, and the median reported pre-mitigation result was 1.1 pCi/L. Of the counties bordering it, 2 have a figure over the 2008 to 2017 laboratory totals: Harrison County reported the largest share at or above 4 pCi/L, 46.8%, and Mason County the smallest, 25.0%.
Which counties border Robertson County?
Robertson County borders 5 counties: Bracken County, Nicholas County, Mason County, Harrison County and Fleming County.
Products
Robertson County, Products
Testing a home in Robertson County
No CDC figure names Robertson County; the nearest county with one, Mason County (13 miles away), reported 25.0% 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 1 the year-round level in Robertson County is the one to know: a long-term test (more than 90 days) or a monitor, with a short-term kit for a first answer.
Test kits and monitors3
See every kit and monitor
Monitor
EcoQube Wi-Fi continuous radon monitor
- C-NRPP 2024/25: Approved
- Plug-in
- Wi-Fi
- App only
Method: Ion chamber
First reading: Within 10 minutes
Short-term kit
Air Chek Short-Term radon test kit you hang, lab fee included
- Lab fee included
In home: 72 to 168 hours
- See every kit and monitor Test kits and monitors
Test kits and monitors: 1 of 3
Robertson County is in EPA Zone 1, the highest predicted radon potential. Best radon monitors for Zone 1 counties like Robertson County
Explore
Robertson County, Bordering counties
Counties bordering Robertson County
Calculated by Radon411- Radon levels in Harrison CountyEPA zone 1
46.8%at or above 4 pCi/L
Median 3.4 pCi/L · 111 tests
- Radon levels in Fleming CountyEPA zone 2
36.4%at or above 4 pCi/L
Median 2.9 pCi/L · 22 tests
- Radon levels in Mason CountyEPA zone 2
25.0%at or above 4 pCi/L
Median 2.6 pCi/L · 32 tests
- Radon levels in Bracken CountyEPA zone 2
20.0%at or above 4 pCi/L
Median 2.0 pCi/L · 5 tests
- Radon levels in Nicholas CountyEPA zone 2
10.0%at or above 4 pCi/L
Median 1.9 pCi/L · 20 tests
Robertson County, Cities and towns
Cities and towns in Robertson County
Robertson County is growing: the Census Bureau puts it at 2,325 residents on July 1, 2025, up 6.6% from 2,182 in 2020. That works out to 23 people per square mile of land. No town dominates: Mount Olivet, the largest, has 363 residents, 15.6% of the total. Reported testing is thin here: 4 tests over 2008 to 2017, or 1.7 for every 1,000 residents (2025 estimate), where Kentucky as a whole comes to 6.3.
From Mount Olivet to Sardis, CDC publishes no figure by town: each reads Robertson County's.
| Place | Residents | Since 2020 | Share of residents |
|---|---|---|---|
| Mount Olivet | 363 | +5.8% | 15.6% |
| Sardisextends beyond Robertson County | 61 | −1.6% | Counted whole |
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). A place that extends beyond Robertson County is counted whole, so it has no share.
Robertson County, Homes
Homes in Robertson County
Of Robertson County's 996 homes, 73% are detached houses, against 68% across Kentucky; 24% are mobile homes. Half of its homes were built before 1980, close to Kentucky's 1982: 32% date from before 1960 and 17% from 2000 or later. Owners live in 75% of the occupied homes (Kentucky: 68%), so for most households a test and a fix are their own to order.
| Homes | Robertson County | Kentucky |
|---|---|---|
| Housing units | 996 | 2,010,655 |
| Detached houses | 73% | 68% |
| In buildings of 5 or more | 1% | 12% |
| Mobile homes | 24% | 11% |
| Built before 1960 | 32% | 22% |
| Built since 2000 | 17% | 24% |
| Middle year built | 1980 | 1982 |
| Owner-occupied | 75% | 68% |
Census Bureau, American Community Survey, 2019 to 2023: estimates from a sample of homes, looser for a small place. Shares by Radon411.