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Radon Levels in Hancock County, Indiana

EPA puts Hancock County in Zone 1, its highest radon zone, and 33.9% of its 271 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

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  • Share at 4+ pCi/L

    33.9%

    5.0 pts below IN

    Hancock
    33.9%
    Indiana
    38.9%

    271 tests, 2008 to 2017

  • Median result

    2.6pCi/L

    Below action level

    Hancock
    2.6 pCi/L
    EPA
    4.0 pCi/L

    Midpoint of the tests, 2008 to 2017

  • Tests reported

    271

    22nd of 69 by tests

    Hancock
    271
    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

    58 of 69

    Lowest quarter

    Hancock
    33.9%
    Miami
    63.3%

    By share, of 69 with 30+ tests

Read a result for Hancock County

Starts at Hancock County's median, 2.6 pCi/L

2.6pCi/L

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

EPA’s reading of 2.6 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. Hancock County's median reported result, 2008 to 2017.

Interpret this readingWhat a fix costs

The data

Hancock County, At a glance

Hancock County at a glance

Predicted: EPA radon zone

EPA Zone 1: highest predicted potential

EPA puts all of Hancock 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 Hancock County, 2008 to 2017, laboratory

Reported results by concentration band, Hancock County, 2008 to 2017, laboratory
Under 2 pCi/L: 41%2 to 4 pCi/L: 25%4 pCi/L and above: 34%

Of 271 pre-mitigation tests reported to CDC, not homes in this area.

Reported results by concentration band, Hancock County, 2008 to 2017, laboratory: data table
Result bandTests MeasuredShare Measured
Under 2 pCi/L11141.0%
2 to 4 pCi/L6825.1%
4 pCi/L and above9233.9%
What these figures count

These are the 271 tests reported to CDC for Hancock 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

Hancock County, Compared

Hancock County radon figures, compared

Calculated by Radon411

In Hancock County, about 3 in 10 reported tests over the 2008 to 2017 laboratory totals (92 of 271) were at or above EPA's action level. Against the national pool of 35.7%, the gap is 1.8 points lower. Across 92 Indiana counties pooled together, 38.9% of tests reached that level, so Hancock County runs 5.0 points below its state.

Of 5 neighbours with a figure, all 5 reported a larger share at or above 4 pCi/L; the spread is 37.6% (Hamilton County) to 50.5% (Henry County). By share, Hancock County is 58th of 69 Indiana counties with 30 or more tests for the same period.

Half the tests came in under 2.6 pCi/L and half over it; the single highest reached 39.7 pCi/L. Below the action level, 111 tests (41.0%) came in under 2 pCi/L, against 32.8% statewide, and 68 tests (25.1%) fell between 2 and 4, against 28.3% statewide.

Zone 1 on EPA's map (predicted average above 4 pCi/L) and a 33.9% share point the same way here. USGS geology rates 100% of the county's land high radon potential. CDC also counts 43 tests taken after mitigation in Hancock County for the same period: tests in homes where a fix was already in.

CDC's ten-year totals for Hancock County went from 252 tests (2005 to 2014) to 271 (2008 to 2017), the share going from 37.3% to 33.9%.

Hancock County against Indiana, the United States and nearby counties, 2008 to 2017, laboratory
AreaTestsAt or above 4 pCi/LMedianDifference from Hancock County
Hancock County27133.9%2.6 pCi/LThis county
Indiana, pooled92 counties, pooled43,14838.9%Not pooled+5.0 points
United States, pooled2,661 counties, pooled2,013,54435.7%Not pooled+1.8 points
Miami Countyhighest in the state3063.3%5.3 pCi/L+29.4 points
Jasper Countylowest in the state7114.1%1.2 pCi/L−19.8 points
Henry County, INborders it9550.5%4.0 pCi/L+16.6 points
Shelby County, INborders it8450.0%4.0 pCi/L+16.1 points
Madison County, INborders it23949.0%3.8 pCi/L+15.1 points
Rush County, INborders it1747.1%3.9 pCi/L+13.2 points
Marion County, INborders it3,66840.1%3.1 pCi/L+6.2 points
Hamilton County, INborders it3,47937.6%2.7 pCi/L+3.7 points
Where Hancock County's reported results fell, 2008 to 2017, laboratory, beside Indiana and the United States
ResultHancock County testsHancock County shareIndiana shareU.S. shareAgainst Indiana
Under 2 pCi/L11141.0%32.8%39.6%+8.2 points
2 to 4 pCi/L6825.1%28.3%24.7%−3.2 points
4 pCi/L and above9233.9%38.9%35.7%−5.0 points
Hancock 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
Jennings County53 of 695735.1%2.8 pCi/L
Daviess County54 of 695834.5%3.1 pCi/L
Putnam County55 of 6911934.5%2.7 pCi/L
Monroe County56 of 692,37534.2%2.8 pCi/L
Cass County57 of 699134.1%2.6 pCi/L
Hancock County58 of 6927133.9%2.6 pCi/L
Decatur County59 of 696333.3%2.8 pCi/L
Greene County60 of 694932.7%3.0 pCi/L
Dearborn County61 of 6913630.1%2.6 pCi/L
St. Joseph County62 of 697,34629.3%2.7 pCi/L
Franklin County63 of 695028.0%2.1 pCi/L
Hancock County ten-year laboratory totals, against Indiana's pooled share
PeriodTestsAt or above 4 pCi/LMedianHighestIndiana, pooledChange from the row before
2008 to 201727133.9%2.6 pCi/L39.7 pCi/L38.9%−2.4 points
2007 to 201626736.3%2.7 pCi/L39.7 pCi/L39.2%−0.4 points
2006 to 201526736.7%2.9 pCi/L39.7 pCi/L39.6%−0.6 points
2005 to 201425237.3%2.9 pCi/L39.7 pCi/L39.3%First on file

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

Hancock County, Geology

The ground under Hancock County

Predicted

USGS's geologic map puts all of Hancock 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 Hancock 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.

Hancock County beside the ground around it

Hancock County has more high-potential ground than Indiana as a whole: 100% of its land against 56.6%. Of the 6 counties that border it, none has as large a share of high-potential ground; Hamilton County comes nearest at 100%.

Share of land by USGS radon potential: Hancock County, the 6 counties bordering it and Indiana
AreaEPA zoneLow potentialModerate potentialHigh potential
Hancock CountyZone 1NoneNone100%
Shelby CountyZone 1NoneNone100%
Marion CountyZone 1NoneNone100%
Henry CountyZone 1NoneNone100%
Rush CountyZone 1NoneNone100%
Hamilton CountyZone 1NoneNone100%
Madison CountyZone 1NoneNone100%
Indiana92 counties, pooled by land areaVariesNone43.4%56.6%

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

Local help

Hancock County, Local resources

Radon testing and mitigation in Hancock County

Listed radon businesses with an address in Hancock County:

Listed radon professionals by town: Greenfield

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

Hancock County, Questions

Questions about radon in Hancock County

Are radon levels high in Hancock County?

Over the 2008 to 2017 laboratory totals, 33.9% of the radon tests reported to CDC for Hancock County, Indiana were at or above 4 pCi/L, and the median reported pre-mitigation result was 2.6 pCi/L. Of 69 Indiana counties with 30 or more tests for the same period, 57 reported a higher share; pooled, the state comes to 38.9%.

Which counties border Hancock County?

Hancock County borders 6 counties: Shelby County, Marion County, Henry County, Rush County, Hamilton County and Madison County.

Products

Hancock County, Products

Testing a home in Hancock County

In Hancock County, 33.9% of 271 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 Hancock 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

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

Explore

Hancock County, Bordering counties

Counties bordering Hancock County

Calculated by Radon411

Hancock County, Cities and towns

Cities and towns in Hancock County

Hancock County is growing: the Census Bureau puts it at 90,969 residents on July 1, 2025, up 13.5% from 80,175 in 2020. That works out to 297 people per square mile of land. Its largest town, Greenfield, has 26,544 residents, 29.2% of the total. Reported testing is thin here: 271 tests over 2008 to 2017, or 3.0 for every 1,000 residents (2025 estimate), where Indiana as a whole comes to 6.2.

From Greenfield to Spring Lake, CDC publishes no figure by town: each reads Hancock County's.

The cities and towns in Hancock County by residents, July 1, 2025
PlaceResidentsSince 2020Share of residents
Greenfield26,544+12.7%29.2%
McCordsville13,094+47.4%14.4%
Cumberlandextends beyond Hancock County8,066+24.6%Counted whole
Fortville4,951+2.8%5.4%
New Palestine3,621+30.9%4.0%
Shirleyextends beyond Hancock County851+3.2%Counted whole
Wilkinson414−2.4%0.5%
Spring Lake216+1.4%0.2%

8 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 Hancock County is counted whole, so it has no share.

Hancock County, Homes

Homes in Hancock County

Hancock County is a place of houses on their own lots: 84% of its 33,398 homes are detached single-family houses, against 73% across Indiana. Much of Hancock County is recent building: 33% of its homes have gone up since 2000 and the middle year built is 1991, against 1976 for Indiana. Owners live in 80% of the occupied homes (Indiana: 70%), so for most households a test and a fix are their own to order.

Homes in Hancock County, Indiana, 2019 to 2023
HomesHancock CountyIndiana
Housing units33,3982,953,344
Detached houses84%73%
In buildings of 5 or more7%13%
Mobile homes1%4%
Built before 196019%32%
Built since 200033%21%
Middle year built19911976
Owner-occupied80%70%

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