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Radon Levels in Trigg County, Kentucky

EPA puts Trigg County in Zone 2, its middle radon zone, and 22.2% of its 45 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

How to test this homeFind a certified tester

  • Share at 4+ pCi/L

    22.2%

    21.5 pts below KY

    Trigg
    22.2%
    Kentucky
    43.7%

    45 tests, 2008 to 2017

  • Median result

    2.4pCi/L

    Below action level

    Trigg
    2.4 pCi/L
    EPA
    4.0 pCi/L

    Midpoint of the tests, 2008 to 2017

  • Tests reported

    45

    54th of 69 by tests

    Trigg
    45
    Jefferson
    6,590

    Reported to CDC before any fix, 2008 to 2017

  • EPA radon zone

    Zone 2

    Moderate potential

    1. 1
    2. Zone 2
    3. 3

    1 highest, 3 lowest

    EPA predicts 2 to 4 pCi/L indoors

  • Rank in Kentucky

    57 of 69

    Lowest quarter

    Trigg
    22.2%
    Meade
    68.4%

    By share, of 69 with 30+ tests

Read a result for Trigg County

Starts at Trigg County's median, 2.4 pCi/L

2.4pCi/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

  1. Under 20 to 1.9 pCi/L
  2. 2 to 4consider a fix
  3. 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. Trigg County's median reported result, 2008 to 2017.

Interpret this readingWhat a fix costs

The data

Trigg County, At a glance

Trigg County at a glance

Predicted: EPA radon zone

EPA Zone 2: moderate predicted potential

Trigg County is a county: EPA's forecast for it as a whole is an average indoor of 2 to 4 pCi/L (75 to 150 Bq/m³). It describes no single address, and homes above EPA's are found in every zone, this one included.

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 Trigg County, 2008 to 2017, laboratory

Reported results by concentration band, Trigg County, 2008 to 2017, laboratory
Under 2 pCi/L: 36%2 to 4 pCi/L: 42%4 pCi/L and above: 22%

Of 45 pre-mitigation tests reported to CDC, not homes in this area.

Reported results by concentration band, Trigg County, 2008 to 2017, laboratory: data table
Result bandTests MeasuredShare Measured
Under 2 pCi/L1635.6%
2 to 4 pCi/L1942.2%
4 pCi/L and above1022.2%
What these figures count

These are the 45 tests reported to CDC for Trigg 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).

How to read these figures

Trigg County, Compared

Trigg County radon figures, compared

Calculated by Radon411

Trigg County's 45 reported tests over the 2008 to 2017 laboratory totals had a middle value of 2.4 pCi/L and a maximum of 14.5 pCi/L, and 22.2% reached 4 pCi/L. Kentucky as a whole (120 Kentucky counties, pooled) comes to 43.7%: 21.5 points higher than here.

Among its state's counties it ranks 57th 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, 16 tests (35.6%) came in under 2 pCi/L, against 33.2% statewide, and 19 tests (42.2%) fell between 2 and 4, against 23.1% statewide. CDC's ten-year totals for Trigg County went from 38 tests (2005 to 2014) to 45 (2008 to 2017), the share going from 42.1% to 22.2%.

EPA's 1993 zone map puts Trigg 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 10.6% in Marshall County to 36.1% in Christian County, with Marshall County below Trigg County.

Trigg County against Kentucky, the United States and nearby counties, 2008 to 2017, laboratory
AreaTestsAt or above 4 pCi/LMedianDifference from Trigg County
Trigg County4522.2%2.4 pCi/LThis county
Kentucky, pooled120 counties, pooled28,79343.7%Not pooled+21.5 points
United States, pooled2,661 counties, pooled2,013,54435.7%Not pooled+13.5 points
Meade Countyhighest in the state11768.4%8.2 pCi/L+46.2 points
Hopkins Countylowest in the state429.5%1.7 pCi/L−12.7 points
Caldwell County, KYborders it2040.0%3.7 pCi/L+17.8 points
Christian County, KYborders it7236.1%3.2 pCi/L+13.9 points
Lyon County, KYborders it1435.7%2.5 pCi/L+13.5 points
Stewart County, TNborders it9526.3%2.1 pCi/L+4.1 points
Calloway County, KYborders it2722.2%2.4 pCi/LLevel
Marshall County, KYborders it8510.6%1.5 pCi/L−11.6 points
Where Trigg County's reported results fell, 2008 to 2017, laboratory, beside Kentucky and the United States
ResultTrigg County testsTrigg County shareKentucky shareU.S. shareAgainst Kentucky
Under 2 pCi/L1635.6%33.2%39.6%+2.4 points
2 to 4 pCi/L1942.2%23.1%24.7%+19.1 points
4 pCi/L and above1022.2%43.7%35.7%−21.5 points
Trigg County ranked among the 69 Kentucky counties with 30 or more tests, by share at or above 4 pCi/L, 2008 to 2017, laboratory
CountyRankTestsAt or above 4 pCi/LMedian
Kenton County52 of 691,16726.0%2.3 pCi/L
Anderson County53 of 6922625.2%2.2 pCi/L
Mason County54 of 693225.0%2.6 pCi/L
Russell County54 of 693225.0%2.9 pCi/L
Henderson County56 of 695424.1%2.3 pCi/L
Trigg County57 of 694522.2%2.4 pCi/L
Laurel County58 of 6910022.0%1.9 pCi/L
Menifee County59 of 694122.0%1.4 pCi/L
Edmonson County60 of 696221.0%1.6 pCi/L
Daviess County61 of 6914520.0%1.8 pCi/L
Breathitt County62 of 694719.1%1.7 pCi/L
Trigg County ten-year laboratory totals, against Kentucky's pooled share
PeriodTestsAt or above 4 pCi/LMedianHighestKentucky, pooledChange from the row before
2008 to 20174522.2%2.4 pCi/L14.5 pCi/L43.7%−13.7 points
2007 to 20163935.9%3.0 pCi/L14.5 pCi/L45.1%−6.2 points
2006 to 20153842.1%3.1 pCi/L14.5 pCi/L46.4%Level
2005 to 20143842.1%3.1 pCi/L14.5 pCi/L47.3%First on file

Pooled shares: Radon411's sum of CDC's county counts for one period.

Trigg County, Geology

The ground under Trigg County

Predicted

USGS's geologic map puts all of Trigg County's mapped land in one class: moderate radon potential. All of it lies in the area the map calls Mississippian Plateau, to which USGS gives a radon index of 11, in the moderate band (9 to 11).

USGS's geologic areas under Trigg County
AreaThe rock, in USGS's wordsPotentialRadon indexShare of land
Mississippian PlateauMississippian marine limestones, dolomites, marine sandstones, siltstones, and shales.Moderate1199.8%

Names, descriptions and indexes: U.S. Geological Survey, Geologic Radon Potential Map (2025). Shares: Radon411, from the map cut to the boundary.

Trigg County beside the ground around it

Across Kentucky 18.2% of the land is rated high; none of Trigg County's is. Of the 6 counties that border it, 2 have more high-potential ground, Stewart County, TN the most at 17.3%.

Share of land by USGS radon potential: Trigg County, the 6 counties bordering it and Kentucky
AreaEPA zoneLow potentialModerate potentialHigh potential
Trigg CountyZone 2None100%None
Lyon CountyZone 2None100%None
Stewart County, TNZone 2None82.7%17.3%
Caldwell CountyZone 2None100%None
Calloway CountyZone 378.2%19.6%2.2%
Marshall CountyZone 368.5%31.5%None
Christian CountyZone 2None100%None
Kentucky120 counties, pooled by land areaVaries5.7%76.1%18.2%

The map rates the ground, not the air in any home.

Local help

Trigg County, Local resources

Radon testing and mitigation in Trigg County

What Kentucky's program says
Phone
502-782-2782
Email
Radon@ky.gov

What it means

Trigg County, Questions

Questions about radon in Trigg County

Are radon levels high in Trigg County?

Over the 2008 to 2017 laboratory totals, 22.2% of the radon tests reported to CDC for Trigg 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, 56 reported a higher share; pooled, the state comes to 43.7%.

Which counties border Trigg County?

Trigg County borders 6 counties: Lyon County, KY, Stewart County, TN, Caldwell County, KY, Calloway County, KY, Marshall County, KY and Christian County, KY.

Products

Trigg County, Products

Testing a home in Trigg County

In Trigg County, 22.2% of 45 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 Trigg County; a long-term test tells the year-round average.

Test kits and monitors3

See every kit and monitor

Best radon monitors for Trigg County homes, compared

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Trigg County, Bordering counties

Counties bordering Trigg County

Calculated by Radon411

Trigg County, Cities and towns

Cities and towns in Trigg County

The Census Bureau estimates 14,512 residents in Trigg County for July 1, 2025, 435 more than in 2020 (+3.1%). That works out to 33 people per square mile of land. Cadiz, its one incorporated place, has 2,771 residents, 19.1% of the total. Reported testing is thin here: 45 tests over 2008 to 2017, or 3.1 for every 1,000 residents (2025 estimate), where Kentucky as a whole comes to 6.3.

Cadiz is the one incorporated place here; CDC publishes no figure by town, so it reads Trigg County's.

Cadiz, Trigg County: residents on July 1, 2025
PlaceResidentsSince 2020Share of residents
Cadiz2,771+7.5%19.1%

One incorporated place, 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).

Trigg County, Homes

Homes in Trigg County

Of Trigg County's 7,625 homes, 74% are detached houses, against 68% across Kentucky; 18% are mobile homes. Half of its homes were built before 1985, close to Kentucky's 1982: 11% date from before 1960 and 25% from 2000 or later. 74% 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 in Trigg County, Kentucky, 2019 to 2023
HomesTrigg CountyKentucky
Housing units7,6252,010,655
Detached houses74%68%
In buildings of 5 or more4%12%
Mobile homes18%11%
Built before 196011%22%
Built since 200025%24%
Middle year built19851982
Owner-occupied74%68%

Census Bureau, American Community Survey, 2019 to 2023: estimates from a sample of homes, looser for a small place. Shares by Radon411.