Skip to content
RADON411

Locations and reports

Radon Levels in Henry County, Indiana

EPA puts Henry County in Zone 1, its highest radon zone, and high results are common there: 50.5% of the 95 radon tests reported to CDC (2008 to 2017, laboratory totals) came back 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

    50.5%

    11.6 pts above IN

    Henry
    50.5%
    Indiana
    38.9%

    95 tests, 2008 to 2017

  • Median result

    4.0pCi/L

    Action level reached

    Henry
    4.0 pCi/L
    EPA
    4.0 pCi/L

    Midpoint of the tests, 2008 to 2017

  • Tests reported

    95

    46th of 69 by tests

    Henry
    95
    St. Joseph
    7,346

    Reported to CDC before any fix, 2008 to 2017

  • EPA radon zone

    Zone 1

    Highest potential

    1. Zone 1
    2. 2
    3. 3

    1 highest, 3 lowest

    EPA predicts over 4 pCi/L indoors

  • Rank in Indiana

    16 of 69

    Top quarter

    Henry
    50.5%
    Miami
    63.3%

    By share, of 69 with 30+ tests

Read a result for Henry County

Starts at Henry County's median, 4.0 pCi/L

4.0pCi/L

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

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

Interpret this readingWhat a fix costs

The data

Henry County, At a glance

Henry County at a glance

Predicted: EPA radon zone

EPA Zone 1: highest predicted potential

EPA puts all of Henry County in and predicts an average indoor of greater than 4 pCi/L (greater than 150 Bq/m³) across the county. That is one forecast for the whole county, not a reading of any address in it; homes above EPA's turn up in all three zones.

USGS geologic potential: High across 100% of the county's area

Predicted: EPA Map of Radon Zones

Measured: tests reported to CDC

Radon tests reported for Henry County, 2008 to 2017, laboratory

Reported results by concentration band, Henry County, 2008 to 2017, laboratory
Under 2 pCi/L: 23%2 to 4 pCi/L: 26%4 pCi/L and above: 51%

Of 95 pre-mitigation tests reported to CDC, not homes in this area.

Reported results by concentration band, Henry County, 2008 to 2017, laboratory: data table
Result bandTests MeasuredShare Measured
Under 2 pCi/L2223.2%
2 to 4 pCi/L2526.3%
4 pCi/L and above4850.5%
What these figures count

These are the 95 tests reported to CDC for Henry 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

Henry County, Compared

Henry County radon figures, compared

Calculated by Radon411

More than half: 50.5% of the 95 radon tests reported to CDC for Henry County over the 2008 to 2017 laboratory totals read at least 4 pCi/L. That places it 16th of 69 Indiana counties with 30 or more tests for the same period. That is 11.6 points above the 38.9% pooled from 92 Indiana counties.

The median result, 4.0 pCi/L, sits above EPA's 4 pCi/L action level, and the top reported result was 50.1 pCi/L. The rest split 23.2% under 2 pCi/L and 26.3% from 2 to 4 (Indiana: 32.8% and 28.3%). Zone 1 on EPA's map (predicted average above 4 pCi/L) and a 50.5% share point the same way here.

2 of its 4 bordering counties with figures ran higher, led by Wayne County at 56.4%; Hancock County reported 33.9%. Statewide for the same period, Miami County reported the highest share (63.3%) and Jasper County the lowest (14.1%).

CDC's ten-year totals for Henry County went from 80 tests (2005 to 2014) to 95 (2008 to 2017), the share going from 47.5% to 50.5%.

Nationally, every county with a figure for the same period pools to 35.7%; Henry County sits 14.8 points above it. CDC also counts 7 tests taken after mitigation in Henry County for the same period: tests in homes where a fix was already in.

Henry County against Indiana, the United States and nearby counties, 2008 to 2017, laboratory
AreaTestsAt or above 4 pCi/LMedianDifference from Henry County
Henry County9550.5%4.0 pCi/LThis county
Indiana, pooled92 counties, pooled43,14838.9%Not pooled−11.6 points
United States, pooled2,661 counties, pooled2,013,54435.7%Not pooled−14.8 points
Miami Countyhighest in the state3063.3%5.3 pCi/L+12.8 points
Jasper Countylowest in the state7114.1%1.2 pCi/L−36.4 points
Fayette County, INborders it1376.9%7.9 pCi/L+26.4 points
Randolph County, INborders it2860.7%4.5 pCi/L+10.2 points
Wayne County, INborders it14056.4%4.5 pCi/L+5.9 points
Delaware County, INborders it18755.1%4.2 pCi/L+4.6 points
Madison County, INborders it23949.0%3.8 pCi/L−1.5 points
Rush County, INborders it1747.1%3.9 pCi/L−3.4 points
Hancock County, INborders it27133.9%2.6 pCi/L−16.6 points
Where Henry County's reported results fell, 2008 to 2017, laboratory, beside Indiana and the United States
ResultHenry County testsHenry County shareIndiana shareU.S. shareAgainst Indiana
Under 2 pCi/L2223.2%32.8%39.6%−9.6 points
2 to 4 pCi/L2526.3%28.3%24.7%−2.0 points
4 pCi/L and above4850.5%38.9%35.7%+11.6 points
Henry County ranked among the 69 Indiana counties with 30 or more tests, by share at or above 4 pCi/L, 2008 to 2017, laboratory
CountyRankTestsAt or above 4 pCi/LMedian
Delaware County11 of 6918755.1%4.2 pCi/L
Fountain County12 of 696055.0%4.6 pCi/L
Noble County13 of 6913652.9%4.3 pCi/L
Whitley County14 of 6918451.6%4.0 pCi/L
Kosciusko County15 of 691,24850.6%4.0 pCi/L
Henry County16 of 699550.5%4.0 pCi/L
Shelby County17 of 698450.0%4.0 pCi/L
Tipton County18 of 696949.3%3.9 pCi/L
Howard County19 of 6921649.1%3.8 pCi/L
Madison County20 of 6923949.0%3.8 pCi/L
Bartholomew County21 of 691,70748.7%3.9 pCi/L
Henry County ten-year laboratory totals, against Indiana's pooled share
PeriodTestsAt or above 4 pCi/LMedianHighestIndiana, pooledChange from the row before
2008 to 20179550.5%4.0 pCi/L50.1 pCi/L38.9%+4.2 points
2007 to 20169546.3%3.6 pCi/L50.1 pCi/L39.2%−0.4 points
2006 to 20159246.7%3.6 pCi/L50.1 pCi/L39.6%−0.8 points
2005 to 20148047.5%3.6 pCi/L50.1 pCi/L39.3%First on file

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

Henry County, Geology

The ground under Henry County

Predicted

USGS's geologic map puts all of Henry County's mapped land in one class: high radon potential. All of it lies in the area the map calls Huron-Erie Lobe, to which USGS gives a radon index of 13, in the high band (12 to 17).

USGS's geologic areas under Henry County
AreaThe rock, in USGS's wordsPotentialRadon indexShare of land
Huron-Erie LobeCalcareous clayey and loamy glacial deposits derived from marine carbonate and clastic sedimentary rocks.High13100%

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

Henry County beside the ground around it

Henry County has more high-potential ground than Indiana as a whole: 100% of its land against 56.6%. Of the 7 counties that border it, none has as large a share of high-potential ground; Delaware County comes nearest at 100%.

Share of land by USGS radon potential: Henry County, the 7 counties bordering it and Indiana
AreaEPA zoneLow potentialModerate potentialHigh potential
Henry CountyZone 1NoneNone100%
Delaware CountyZone 1NoneNone100%
Wayne CountyZone 1NoneNone100%
Rush CountyZone 1NoneNone100%
Hancock CountyZone 1NoneNone100%
Fayette CountyZone 1None7.1%92.9%
Madison CountyZone 1NoneNone100%
Randolph CountyZone 1NoneNone100%
Indiana92 counties, pooled by land areaVariesNone43.4%56.6%

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

Local help

Henry County, Local resources

Radon testing and mitigation in Henry County

What Indiana's program says
Phone
1-800-272-9723
Licensing of radon professionals
According to the Indiana Radon Rule, 410 IAC 5.1, everyone who is serving Indiana by doing radon testing, analysis and mitigation (radon reduction) in residential structures must be certified by the Indiana State Department of Health.

What it means

Henry County, Questions

Questions about radon in Henry County

Are radon levels high in Henry County?

Over the 2008 to 2017 laboratory totals, 50.5% of the radon tests reported to CDC for Henry County, Indiana were at or above 4 pCi/L, and the median reported pre-mitigation result was 4.0 pCi/L. Of 69 Indiana counties with 30 or more tests for the same period, 15 reported a higher share; pooled, the state comes to 38.9%.

Which counties border Henry County?

Henry County borders 7 counties: Delaware County, Wayne County, Rush County, Hancock County, Fayette County, Madison County and Randolph County.

Products

Henry County, Products

Testing a home in Henry County

In Henry County, 50.5% of 95 tests reported to CDC over the 2008 to 2017 laboratory totals reached 4 pCi/L, against 38.9% pooled across Indiana. In Zone 1 the year-round level in Henry 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

Henry County is in EPA Zone 1, the highest predicted radon potential. Best radon monitors for Zone 1 counties like Henry County

Explore

Henry County, Bordering counties

Counties bordering Henry County

Calculated by Radon411

Henry County, Cities and towns

Cities and towns in Henry County

Henry County's population has barely moved since 2020: 49,137 residents on July 1, 2025 against 48,905 then, by the Census Bureau's estimates. That works out to 125 people per square mile of land. Its largest town, New Castle, has 17,390 residents, 35.4% of the total. Reported testing is thin here: 95 tests over 2008 to 2017, or 1.9 for every 1,000 residents (2025 estimate), where Indiana as a whole comes to 6.2.

From New Castle to Blountsville, CDC publishes no figure by town: each reads Henry County's.

The 12 largest cities and towns in Henry County by residents, July 1, 2025
PlaceResidentsSince 2020Share of residents
New Castle17,390Level35.4%
Middletown2,248+0.2%4.6%
Knightstown2,165+0.9%4.4%
Spiceland961+0.4%2.0%
Shirleyextends beyond Henry County851+3.2%Counted whole
Kennard447Level0.9%
Mount Summit353+0.6%0.7%
Mooreland341+0.6%0.7%
Sulphur Springs337+1.2%0.7%
Lewisville335+0.6%0.7%
Straughn267+0.8%0.5%
Dunreith172+1.2%0.4%
  • Cadiz
  • Springport
  • Greensboro
  • Blountsville

16 incorporated places, as listed in the U.S. Census Bureau’s 2020 place reference files. “(part)” marks a place that extends into another county. Residents: U.S. Census Bureau population estimates for July 1, 2025 (Vintage 2025). A place that extends beyond Henry County is counted whole, so it has no share.

Henry County, Homes

Homes in Henry County

Henry County is a place of houses on their own lots: 83% of its 20,968 homes are detached single-family houses, against 73% across Indiana. The homes are older than Indiana's as a whole: half were built before 1959 (1976 for Indiana), and 52% date from before 1960. Owners live in 76% of the occupied homes (Indiana: 70%), so for most households a test and a fix are their own to order.

Homes in Henry County, Indiana, 2019 to 2023
HomesHenry CountyIndiana
Housing units20,9682,953,344
Detached houses83%73%
In buildings of 5 or more6%13%
Mobile homes4%4%
Built before 196052%32%
Built since 20009%21%
Middle year built19591976
Owner-occupied76%70%

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