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 Madison County, Indiana
EPA puts Madison County in Zone 1, its highest radon zone, and high results are common there: 49.0% of the 239 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
49.0%
10.1 pts above IN
- Madison
- 49.0%
- Indiana
- 38.9%
239 tests, 2008 to 2017
Median result
3.8pCi/L
Below action level
- Madison
- 3.8 pCi/L
- EPA
- 4.0 pCi/L
Midpoint of the tests, 2008 to 2017
Tests reported
239
25th of 69 by tests
- Madison
- 239
- 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
20 of 69
Middle half
- Madison
- 49.0%
- Miami
- 63.3%
By share, of 69 with 30+ tests
Read a result for Madison County
Starts at Madison County's median, 3.8 pCi/L
EPA’s own thresholds; the figures are the area’s, never this home’s.
EPA’s reading of 3.8 pCi/L
Between 2 and 4 pCi/L
- Under 20 to 1.9 pCi/L
- 2 to 4consider a fix
- 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. Madison County's median reported result, 2008 to 2017.
The data
Madison County, At a glance
Madison County at a glance
Predicted: EPA radon zone
EPA Zone 1: highest predicted potential
EPA puts all of Madison 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 Madison County, 2008 to 2017, laboratory
Under 2 pCi/L: 25%2 to 4 pCi/L: 26%4 pCi/L and above: 49%
Of 239 pre-mitigation tests reported to CDC, not homes in this area.
| Result band | Tests Measured | Share Measured |
|---|---|---|
| Under 2 pCi/L | 59 | 24.7% |
| 2 to 4 pCi/L | 63 | 26.4% |
| 4 pCi/L and above | 117 | 49.0% |
What these figures count
These are the 239 tests reported to CDC for Madison 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).
Madison County, Compared
Madison County radon figures, compared
Calculated by Radon411In Madison County, about 5 in 10 reported tests over the 2008 to 2017 laboratory totals (117 of 239) were at or above EPA's action level. Against the national pool of 35.7%, the gap is 13.3 points higher. Across 92 Indiana counties pooled together, 38.9% of tests reached that level, so Madison County runs 10.1 points above its state.
Of 6 neighbours with a figure, 4 reported a larger share at or above 4 pCi/L and 2 a smaller one; the spread is 33.9% (Hancock County) to 58.2% (Grant County). By share, Madison County is 20th of 69 Indiana counties with 30 or more tests for the same period.
Half the tests came in under 3.8 pCi/L and half over it; the single highest reached 51.5 pCi/L. Below the action level, 59 tests (24.7%) came in under 2 pCi/L, against 32.8% statewide, and 63 tests (26.4%) fell between 2 and 4, against 28.3% statewide.
Zone 1 on EPA's map (predicted average above 4 pCi/L) and a 49.0% share point the same way here. USGS geology rates 100% of the county's land high radon potential. CDC also counts 31 tests taken after mitigation in Madison County for the same period: tests in homes where a fix was already in.
CDC's ten-year totals for Madison County went from 267 tests (2005 to 2014) to 239 (2008 to 2017), the share going from 43.8% to 49.0%.
Pooled shares: Radon411's sum of CDC's county counts for one period.
Madison County, Geology
The ground under Madison County
PredictedUSGS's geologic map puts all of Madison 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.
Madison County beside the ground around it
Madison 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; Delaware County comes nearest at 100%.
The map rates the ground, not the air in any home.
Local help
Madison County, Local resources
Radon testing and mitigation in Madison 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
Madison County, Questions
Questions about radon in Madison County
Are radon levels high in Madison County?
Over the 2008 to 2017 laboratory totals, 49.0% of the radon tests reported to CDC for Madison County, Indiana were at or above 4 pCi/L, and the median reported pre-mitigation result was 3.8 pCi/L. Of 69 Indiana counties with 30 or more tests for the same period, 19 reported a higher share; pooled, the state comes to 38.9%.
Which counties border Madison County?
Madison County borders 6 counties: Delaware County, Hamilton County, Tipton County, Hancock County, Grant County and Henry County.
Products
Madison County, Products
Testing a home in Madison County
In Madison County, 49.0% of 239 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 Madison 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
lüft plug-in radon and indoor air quality monitor
- C-NRPP 2024/25: Approved
- Plug-in
- Wi-Fi, Bluetooth
- App only
First reading: Within 90 minutes
Short-term kitempowerDX
Standard Radon Test short-term mail-in radon test kit
- Lab fee included
Method: Passive sampler
In home: 48 to 96 hours
- See every kit and monitor Test kits and monitors
Test kits and monitors: 1 of 3
Madison County is in EPA Zone 1, the highest predicted radon potential. Best radon monitors for Zone 1 counties like Madison County
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Madison County, Bordering counties
Counties bordering Madison County
Calculated by Radon411- Radon levels in Grant CountyEPA zone 1
58.2%at or above 4 pCi/L
Median 4.6 pCi/L · 79 tests · 9.2 points above Madison County
- Radon levels in Delaware CountyEPA zone 1
55.1%at or above 4 pCi/L
Median 4.2 pCi/L · 187 tests · 6.1 points above Madison County
- Radon levels in Henry CountyEPA zone 1
50.5%at or above 4 pCi/L
Median 4.0 pCi/L · 95 tests · 1.5 points above Madison County
- Radon levels in Tipton CountyEPA zone 1
49.3%at or above 4 pCi/L
Median 3.9 pCi/L · 69 tests · 0.3 points above Madison County
- Radon levels in Hamilton CountyEPA zone 1
37.6%at or above 4 pCi/L
Median 2.7 pCi/L · 3,479 tests · 11.4 points below Madison County
- Radon levels in Hancock CountyEPA zone 1
33.9%at or above 4 pCi/L
Median 2.6 pCi/L · 271 tests · 15.1 points below Madison County
Madison County, Cities and towns
Cities and towns in Madison County
The Census Bureau estimates 135,088 residents in Madison County for July 1, 2025, 4,933 more than in 2020 (+3.8%). That works out to 299 people per square mile of land. Its largest town, Anderson, has 56,153 residents, 41.6% of the total. Reported testing is thin here: 239 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 Anderson to River Forest, CDC publishes no figure by town: each reads Madison County's.
| Place | Residents | Since 2020 | Share of residents |
|---|---|---|---|
| Anderson | 56,153 | +2.5% | 41.6% |
| Elwoodextends beyond Madison County | 8,525 | +1.5% | Counted whole |
| Pendleton | 5,930 | +25.3% | 4.4% |
| Alexandria | 5,223 | +1.7% | 3.9% |
| Ingalls | 2,635 | +14.2% | 2.0% |
| Lapel | 2,570 | +10.3% | 1.9% |
| Chesterfieldextends beyond Madison County | 2,523 | +1.7% | Counted whole |
| Edgewood | 2,087 | +1.4% | 1.5% |
| Frankton | 1,827 | +3.2% | 1.4% |
| Summitville | 991 | +1.7% | 0.7% |
| Markleville | 493 | +1.4% | 0.4% |
| Orestes | 340 | +4.0% | 0.3% |
- Country Club Heights
- Woodlawn Heights
- River Forest
15 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 Madison County is counted whole, so it has no share.
Madison County, Homes
Homes in Madison County
Madison County is a place of houses on their own lots: 77% of its 59,075 homes are detached single-family houses, against 73% across Indiana. The homes are older than Indiana's as a whole: half were built before 1965 (1976 for Indiana), and 42% date from before 1960. 70% 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 | Madison County | Indiana |
|---|---|---|
| Housing units | 59,075 | 2,953,344 |
| Detached houses | 77% | 73% |
| In buildings of 5 or more | 7% | 13% |
| Mobile homes | 6% | 4% |
| Built before 1960 | 42% | 32% |
| Built since 2000 | 12% | 21% |
| Middle year built | 1965 | 1976 |
| Owner-occupied | 70% | 70% |
Census Bureau, American Community Survey, 2019 to 2023: estimates from a sample of homes, looser for a small place. Shares by Radon411.