Long-term kit
RL116 long-term radon test kit
- Lab fee extra
Method: Alpha track
In home: 90 days to 12 months
Locations and reports
Radon Levels in Shelby County, Indiana
EPA puts Shelby County in Zone 1, its highest radon zone, and high results are common there: 50.0% of the 84 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
Share at 4+ pCi/L
50.0%
11.1 pts above IN
- Shelby
- 50.0%
- Indiana
- 38.9%
84 tests, 2008 to 2017
Median result
4.0pCi/L
Action level reached
- Shelby
- 4.0 pCi/L
- EPA
- 4.0 pCi/L
Midpoint of the tests, 2008 to 2017
Tests reported
84
51st of 69 by tests
- Shelby
- 84
- St. Joseph
- 7,346
Reported to CDC before any fix, 2008 to 2017
EPA radon zone
Zone 1
Highest potential
- Zone 1
- 2
- 3
1 highest, 3 lowest
EPA predicts over 4 pCi/L indoors
Rank in Indiana
17 of 69
Top quarter
- Shelby
- 50.0%
- Miami
- 63.3%
By share, of 69 with 30+ tests
Read a result for Shelby County
Starts at Shelby County's median, 4.0 pCi/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
- 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. Shelby County's median reported result, 2008 to 2017.
The data
Shelby County, At a glance
Shelby County at a glance
Predicted: EPA radon zone
EPA Zone 1: highest predicted potential
EPA puts all of Shelby County in
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 Shelby County, 2008 to 2017, laboratory
Under 2 pCi/L: 37%2 to 4 pCi/L: 13%4 pCi/L and above: 50%
Of 84 pre-mitigation tests reported to CDC, not homes in this area.
| Result band | Tests Measured | Share Measured |
|---|---|---|
| Under 2 pCi/L | 31 | 36.9% |
| 2 to 4 pCi/L | 11 | 13.1% |
| 4 pCi/L and above | 42 | 50.0% |
What these figures count
These are the 84 tests reported to CDC for Shelby 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).
Shelby County, Compared
Shelby County radon figures, compared
Calculated by Radon411More than half: 50.0% of the 84 radon tests reported to CDC for Shelby County over the 2008 to 2017 laboratory totals read at least 4 pCi/L. That places it 17th of 69 Indiana counties with 30 or more tests for the same period. That is 11.1 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 39.5 pCi/L. The rest split 36.9% under 2 pCi/L and 13.1% from 2 to 4 (Indiana: 32.8% and 28.3%). Zone 1 on EPA's map (predicted average above 4 pCi/L) and a 50.0% share point the same way here.
No bordering county with a figure for the same period reported a higher share; the closest is Bartholomew County at 48.7%, the lowest Decatur County at 33.3%. 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 Shelby County went from 77 tests (2005 to 2014) to 84 (2008 to 2017), the share going from 39.0% to 50.0%.
Nationally, every county with a figure for the same period pools to 35.7%; Shelby County sits 14.3 points above it. CDC also counts 9 tests taken after mitigation in Shelby County for the same period: tests in homes where a fix was already in.
Pooled shares: Radon411's sum of CDC's county counts for one period.
Shelby County, Geology
The ground under Shelby County
PredictedUSGS's geologic map puts all of Shelby 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).
| Area | The rock, in USGS's words | Potential | Radon index | Share of land |
|---|---|---|---|---|
| Huron-Erie Lobe | Calcareous clayey and loamy glacial deposits derived from marine carbonate and clastic sedimentary rocks. | High | 13 | 100% |
Names, descriptions and indexes: U.S. Geological Survey, Geologic Radon Potential Map (2025). Shares: Radon411, from the map cut to the boundary.
Shelby County beside the ground around it
Shelby 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; Hancock County comes nearest at 100%.
The map rates the ground, not the air in any home.
Local help
Shelby County, Local resources
Radon testing and mitigation in Shelby County
- Indiana's radon programIndiana Department of HealthIndiana's radon program licenses or certifies radon professionals and offers free or discounted test kits, and answers questions about testing and mitigation in Indiana.Visit the program’s page(opens in a new tab)
- Free and low-cost kitsThe program says:
To purchase a low-cost radon short term or long term test kit, please visit the American Lung Association
- Compare kits
- Professionals in Indiana17 professionals are listed in Indiana.
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
Shelby County, Questions
Questions about radon in Shelby County
Are radon levels high in Shelby County?
Over the 2008 to 2017 laboratory totals, 50.0% of the radon tests reported to CDC for Shelby 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, 16 reported a higher share; pooled, the state comes to 38.9%.
Which counties border Shelby County?
Shelby County borders 6 counties: Johnson County, Rush County, Hancock County, Bartholomew County, Decatur County and Marion County.
Products
Shelby County, Products
Testing a home in Shelby County
In Shelby County, 50.0% of 84 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 Shelby 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
View Plus radon and air quality monitor
- C-NRPP 2024/25: Approved
- Battery
- Wi-Fi, Bluetooth
- Screen, app
Method: Alpha spectrometry
Short-term kit
PicoCan short-term charcoal canister radon test
- Lab fee included
Method: Charcoal
In home: 48 to 96 hours
- See every kit and monitor Test kits and monitors
Test kits and monitors: 1 of 3
Shelby County is in EPA Zone 1, the highest predicted radon potential. Best radon monitors for Zone 1 counties like Shelby County
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Shelby County, Bordering counties
Counties bordering Shelby County
Calculated by Radon411- Radon levels in Bartholomew CountyEPA zone 1
48.7%at or above 4 pCi/L
Median 3.9 pCi/L · 1,707 tests · 1.3 points below Shelby County
- Radon levels in Rush CountyEPA zone 1
47.1%at or above 4 pCi/L
Median 3.9 pCi/L · 17 tests · 2.9 points below Shelby County
- Radon levels in Marion CountyEPA zone 1
40.1%at or above 4 pCi/L
Median 3.1 pCi/L · 3,668 tests · 9.9 points below Shelby County
- Radon levels in Johnson CountyEPA zone 1
39.4%at or above 4 pCi/L
Median 2.9 pCi/L · 556 tests · 10.6 points below Shelby County
- Radon levels in Hancock CountyEPA zone 1
33.9%at or above 4 pCi/L
Median 2.6 pCi/L · 271 tests · 16.1 points below Shelby County
- Radon levels in Decatur CountyEPA zone 1
33.3%at or above 4 pCi/L
Median 2.8 pCi/L · 63 tests · 16.7 points below Shelby County
Shelby County, Cities and towns
Cities and towns in Shelby County
The Census Bureau estimates 45,882 residents in Shelby County for July 1, 2025, 817 more than in 2020 (+1.8%). That works out to 112 people per square mile of land. Its largest town, Shelbyville, has 21,204 residents, 46.2% of the total. Reported testing is thin here: 84 tests over 2008 to 2017, or 1.8 for every 1,000 residents (2025 estimate), where Indiana as a whole comes to 6.2.
From Shelbyville to Fairland, CDC publishes no figure by town: each reads Shelby County's.
| Place | Residents | Since 2020 | Share of residents |
|---|---|---|---|
| Shelbyville | 21,204 | +5.3% | 46.2% |
| Edinburghextends beyond Shelby County | 4,575 | +3.1% | Counted whole |
| Morristown | 1,183 | −2.2% | 2.6% |
| St. Paulextends beyond Shelby County | 974 | +1.4% | Counted whole |
| Fairland | 536 | −1.3% | 1.2% |
5 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 Shelby County is counted whole, so it has no share.
Shelby County, Homes
Homes in Shelby County
Shelby County is a place of houses on their own lots: 79% of its 19,576 homes are detached single-family houses, against 73% across Indiana. Half of its homes were built before 1971, close to Indiana's 1976: 37% date from before 1960 and 16% from 2000 or later. 74% of occupied homes are lived in by their owner (Indiana: 70%); in the rest a tenant can run a test, but a fix is the landlord's to make.
| Homes | Shelby County | Indiana |
|---|---|---|
| Housing units | 19,576 | 2,953,344 |
| Detached houses | 79% | 73% |
| In buildings of 5 or more | 9% | 13% |
| Mobile homes | 5% | 4% |
| Built before 1960 | 37% | 32% |
| Built since 2000 | 16% | 21% |
| Middle year built | 1971 | 1976 |
| Owner-occupied | 74% | 70% |
Census Bureau, American Community Survey, 2019 to 2023: estimates from a sample of homes, looser for a small place. Shares by Radon411.