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Radon Levels in Caledonia County, Vermont

EPA puts Caledonia County in Zone 2, its middle radon zone, and 21.1% of its 76 reported radon tests (2023) 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

    21.1%

    0.5 pts above VT

    Caledonia
    21.1%
    Vermont
    20.6%

    76 tests, 2023

  • Median result

    2.0pCi/L

    Below action level

    Caledonia
    2.0 pCi/L
    EPA
    4.0 pCi/L

    Midpoint of the tests, 2023

  • Tests reported

    76

    5th of 12 by tests

    Caledonia
    76
    Chittenden
    398

    Reported to CDC before any fix, 2023

  • 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 Vermont

    9 of 12

    Middle half

    Caledonia
    21.1%
    Bennington
    29.5%

    By share, of 12 with 30+ tests

Read a result for Caledonia County

Starts at Caledonia County's median, 2.0 pCi/L

2.0pCi/L

EPA’s own thresholds; the figures are the area’s, never this home’s.

EPA’s reading of 2.0 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. Caledonia County's median reported result, 2023.

Interpret this readingWhat a fix costs

The data

Caledonia County, At a glance

Caledonia County at a glance

Predicted: EPA radon zone

EPA Zone 2: moderate predicted potential

Caledonia 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 Caledonia County, 2023

Share of reported tests at or above 4 pCi/L, by year, Caledonia County
Share of reported tests at or above 4 pCi/L, by year, Caledonia County
YearShare of reported tests at or above 4 pCi/L
201430.0%
201524.5%
201616.7%
201723.5%
201825.0%
201932.8%
202036.0%
202126.3%
202232.8%
202321.1%

2023: 21.1%. Across these years the share ran from 16.7% to 36.0%. Each column counts radon tests reported to CDC that year, not homes.

What these figures count

These are the 76 tests reported to CDC for Caledonia County over 2023, 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: 2023. Measured data period: 2005 to 2023 (every CDC figure on file).

How to read these figures

Caledonia County, Compared

Caledonia County radon figures, compared

Calculated by Radon411

Caledonia County's 76 reported tests in 2023 had a middle value of 2.0 pCi/L and a maximum of 14.0 pCi/L, and 21.1% reached 4 pCi/L. Vermont as a whole (14 Vermont counties, pooled) comes to 20.6%: 0.5 points lower than here.

Among its state's counties it ranks 9th of 12 Vermont counties with 30 or more tests for the same period. Statewide for the same period, Bennington County reported the highest share (29.5%) and Chittenden County the lowest (14.6%).

Below the action level, 36 tests (47.4%) came in under 2 pCi/L, against 56.8% statewide, and 24 tests (31.6%) fell between 2 and 4, against 22.5% statewide. The busiest year on file was 2022, with 174 tests reported; the quietest, 2014, had 30.

EPA's 1993 zone map puts Caledonia 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 21.6% in Orleans County to 26.4% in Orange County. Over 10 years of annual figures the share fell 8.9 points, from 30.0% in 2014 to 21.1% in 2023; its peak was 36.0% in 2020.

Share of reported tests at or above 4 pCi/L by year, Caledonia County against Vermont2014 to 2023, years with 30 or more tests: Caledonia County 30.0% to 21.1%, the state's pooled share 20.6% in 2023.
Caledonia CountyVermont, pooled
Share of reported tests at or above 4 pCi/L by year, Caledonia County against Vermont: data table
YearTestsCaledonia County, at or above 4 pCi/LVermont, pooled
20143030.0%18.3%
20154924.5%15.5%
20164816.7%15.9%
20175123.5%16.4%
20184025.0%15.8%
20196732.8%14.3%
20208636.0%16.5%
20219526.3%19.2%
202217432.8%19.4%
20237621.1%20.6%
Caledonia County against Vermont, the United States and nearby counties, 2023
AreaTestsAt or above 4 pCi/LMedianDifference from Caledonia County
Caledonia County7621.1%2.0 pCi/LThis county
Vermont, pooled14 counties, pooled1,30020.6%Not pooled−0.5 points
United States, pooled642 counties, pooled128,74033.4%Not pooled+12.3 points
Bennington Countyhighest in the state4429.5%2.0 pCi/L+8.4 points
Chittenden Countylowest in the state39814.6%1.3 pCi/L−6.5 points
Essex County, VTborders it1050.0%3.0 pCi/L+28.9 points
Orange County, VTborders it5326.4%2.5 pCi/L+5.3 points
Washington County, VTborders it19926.1%2.0 pCi/L+5.0 points
Lamoille County, VTborders it6222.6%1.8 pCi/L+1.5 points
Orleans County, VTborders it5121.6%1.7 pCi/L+0.5 points
Where Caledonia County's reported results fell, 2023, beside Vermont and the United States
ResultCaledonia County testsCaledonia County shareVermont shareU.S. shareAgainst Vermont
Under 2 pCi/L3647.4%56.8%41.4%−9.4 points
2 to 4 pCi/L2431.6%22.5%25.2%+9.1 points
4 pCi/L and above1621.1%20.6%33.4%+0.5 points
Caledonia County ranked among the 12 Vermont counties with 30 or more tests, by share at or above 4 pCi/L, 2023
CountyRankTestsAt or above 4 pCi/LMedian
Orange County2 of 125326.4%2.5 pCi/L
Washington County3 of 1219926.1%2.0 pCi/L
Franklin County4 of 124723.4%1.5 pCi/L
Lamoille County5 of 126222.6%1.8 pCi/L
Windsor County6 of 126722.4%1.6 pCi/L
Windham County7 of 126021.7%2.2 pCi/L
Orleans County8 of 125121.6%1.7 pCi/L
Caledonia County9 of 127621.1%2.0 pCi/L
Addison County10 of 128319.3%1.7 pCi/L
Rutland County11 of 1213018.5%1.3 pCi/L
Chittenden County12 of 1239814.6%1.3 pCi/L
Caledonia County radon tests by year, against Vermont's pooled share
YearTestsAt or above 4 pCi/LMedianHighestVermont, pooledChange from the row before
20237621.1%2.0 pCi/L14.0 pCi/L20.6%−11.7 points
202217432.8%2.7 pCi/L39.2 pCi/L19.4%+6.5 points
20219526.3%1.8 pCi/L36.3 pCi/L19.2%−9.7 points
20208636.0%2.5 pCi/L12.2 pCi/L16.5%+3.2 points
20196732.8%2.7 pCi/L16.5 pCi/L14.3%+7.8 points
20184025.0%2.0 pCi/L25.6 pCi/L15.8%+1.5 points
20175123.5%1.6 pCi/L13.7 pCi/L16.4%+6.8 points
20164816.7%1.6 pCi/L13.8 pCi/L15.9%−7.8 points
20154924.5%2.2 pCi/L11.0 pCi/L15.5%−5.5 points
20143030.0%2.5 pCi/L22.0 pCi/L18.3%First on file

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

Caledonia County, Geology

The ground under Caledonia County

Predicted

USGS's geologic map puts all of Caledonia County's mapped land in one class: moderate radon potential. The map puts 82.6% of Caledonia County in the area it calls Vermont Piedmont and 9.4% in Vermont Piedmont, with one smaller area beside them. USGS gives both a radon index of 11, in the moderate band (9 to 11).

USGS's geologic areas under Caledonia County
AreaThe rock, in USGS's wordsPotentialRadon indexShare of land
Vermont PiedmontPaleozoic metavolcanic and metasedimentary rocks that are intruded by igneous plutonic rocks.Moderate1182.6%
Vermont PiedmontGranite and granitic gneiss of the New Hampshire plutonic series.Moderate119.4%
Northeastern HighlandsPaleozoic to Mesozoic igneous rocks intruded into Silurian-Devonian metasedimentary and metavolcanic rocks.Moderate117.8%

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

Caledonia County beside the ground around it

Caledonia County has more moderate-potential ground than Vermont as a whole: 100% of its land against 87.8%. Of the 6 counties that border it, 1 has more high-potential ground, Grafton County, NH the most at 17.7%.

Share of land by USGS radon potential: Caledonia County, the 6 counties bordering it and Vermont
AreaEPA zoneLow potentialModerate potentialHigh potential
Caledonia CountyZone 2None100%None
Orleans CountyZone 2None99.7%None
Essex CountyZone 2None100%None
Lamoille CountyZone 2None100%None
Washington CountyZone 2None100%None
Orange CountyZone 2None100%None
Grafton County, NHZone 23.5%78.8%17.7%
Vermont14 counties, pooled by land areaVaries12.2%87.8%None

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

Local help

Caledonia County, Local resources

Radon testing and mitigation in Caledonia County

What Vermont's program says
Phone
802-863-7220

What it means

Caledonia County, Questions

Questions about radon in Caledonia County

Are radon levels high in Caledonia County?

In 2023, 21.1% of the radon tests reported to CDC for Caledonia County, Vermont were at or above 4 pCi/L, and the median reported pre-mitigation result was 2.0 pCi/L. Of 12 Vermont counties with 30 or more tests for the same period, 8 reported a higher share; pooled, the state comes to 20.6%.

Which counties border Caledonia County?

Caledonia County borders 6 counties: Orleans County, VT, Essex County, VT, Lamoille County, VT, Washington County, VT, Orange County, VT and Grafton County, NH.

Products

Caledonia County, Products

Testing a home in Caledonia County

In Caledonia County, 21.1% of 76 tests reported to CDC in 2023 reached 4 pCi/L, against 20.6% pooled across Vermont. In Zone 2 a short-term kit (2 to 90 days) is the quick first check in Caledonia County; a long-term test tells the year-round average.

Test kits and monitors3

See every kit and monitor

Best radon monitors for Caledonia County homes, compared

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Caledonia County, Bordering counties

Counties bordering Caledonia County

Calculated by Radon411

Caledonia County, Cities and towns

Cities and towns in Caledonia County

The Census Bureau estimates 30,414 residents in Caledonia County for July 1, 2025, 234 more than in 2020 (+0.8%). That works out to 47 people per square mile of land. No town dominates: West Burke, the largest, has 275 residents, 0.9% of the total. CDC's 76 reported tests for 2023 work out to 2.5 per 1,000 residents (2025 estimate), close to Vermont's 2.0.

From West Burke to Lyndonville, CDC publishes no figure by town: each reads Caledonia County's.

West Burke, Caledonia County: residents on July 1, 2025
PlaceResidentsSince 2020Share of residents
West Burke275−0.7%0.9%
  • Lyndonville

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).

Caledonia County, Homes

Homes in Caledonia County

Of Caledonia County's 16,084 homes, 75% are detached houses, against 67% across Vermont; 9% are mobile homes. Half of its homes were built before 1972, close to Vermont's 1976: 41% date from before 1960 and 19% from 2000 or later. Owners live in 78% of the occupied homes (Vermont: 73%), so for most households a test and a fix are their own to order.

Homes in Caledonia County, Vermont, 2019 to 2023
HomesCaledonia CountyVermont
Housing units16,084337,072
Detached houses75%67%
In buildings of 5 or more6%11%
Mobile homes9%6%
Built before 196041%33%
Built since 200019%17%
Middle year built19721976
Owner-occupied78%73%

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