Long-term kit
RL416 long-term radon test kit, lab fee included
- Lab fee included
Method: Alpha track
In home: 90 days to 12 months
Locations and reports
Radon Levels in Benton County, Iowa
EPA puts Benton County in Zone 1, its highest radon zone, and high results are common there: 62.1% of the 696 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
62.1%
3.6 pts above IA
- Benton
- 62.1%
- Iowa
- 58.5%
696 tests, 2008 to 2017
Median result
5.6pCi/L
Action level reached
- Benton
- 5.6 pCi/L
- EPA
- 4.0 pCi/L
Midpoint of the tests, 2008 to 2017
Tests reported
696
34th of 99 by tests
- Benton
- 696
- Polk
- 10,945
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 Iowa
57 of 99
Middle half
- Benton
- 62.1%
- Sioux
- 84.2%
By share, of 99 with 30+ tests
Read a result for Benton County
Starts at Benton County's median, 5.6 pCi/L
EPA’s own thresholds; the figures are the area’s, never this home’s.
EPA’s reading of 5.6 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. Benton County's median reported result, 2008 to 2017.
The data
Benton County, At a glance
Benton County at a glance
Predicted: EPA radon zone
EPA Zone 1: highest predicted potential
EPA puts all of Benton 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 Benton County, 2008 to 2017, laboratory
Under 2 pCi/L: 19%2 to 4 pCi/L: 19%4 pCi/L and above: 62%
Of 696 pre-mitigation tests reported to CDC, not homes in this area.
| Result band | Tests Measured | Share Measured |
|---|---|---|
| Under 2 pCi/L | 132 | 19.0% |
| 2 to 4 pCi/L | 132 | 19.0% |
| 4 pCi/L and above | 432 | 62.1% |
What these figures count
These are the 696 tests reported to CDC for Benton 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).
Benton County, Compared
Benton County radon figures, compared
Calculated by Radon411More than half: 62.1% of the 696 radon tests reported to CDC for Benton County over the 2008 to 2017 laboratory totals read at least 4 pCi/L. That places it 57th of 99 Iowa counties with 30 or more tests for the same period. That is 3.6 points above the 58.5% pooled from 99 Iowa counties.
The median result, 5.6 pCi/L, sits above EPA's 4 pCi/L action level, and the top reported result was 121.7 pCi/L. The rest split 19.0% under 2 pCi/L and 19.0% from 2 to 4 (Iowa: 21.8% and 19.7%). Zone 1 on EPA's map (predicted average above 4 pCi/L) and a 62.1% share point the same way here.
2 of its 7 bordering counties with figures ran higher, led by Poweshiek County at 70.6%; Linn County reported 39.7%. Statewide for the same period, Sioux County reported the highest share (84.2%) and Decatur County the lowest (25.9%).
CDC's ten-year totals for Benton County went from 573 tests (2005 to 2014) to 696 (2008 to 2017), the share going from 66.5% to 62.1%.
Nationally, every county with a figure for the same period pools to 35.7%; Benton County sits 26.4 points above it. CDC also counts 86 tests taken after mitigation in Benton 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.
Benton County, Geology
The ground under Benton County
PredictedUSGS's geologic map puts all of Benton County's mapped land in one class: high radon potential. The map puts 83.5% of Benton County in the area it calls Iowan Surface and 16.5% in Loess-Covered Drift Plains. USGS gives the first a radon index of 12 and the second 13, both in the high band (12 to 17).
| Area | The rock, in USGS's words | Potential | Radon index | Share of land |
|---|---|---|---|---|
| Iowan Surface | Pre-Illinoian glaical deposits and loess. | High | 12 | 83.5% |
| Loess-Covered Drift Plains | Pre-Illinoian and Illinoian glacial deposits, and loess. | High | 13 | 16.5% |
Names, descriptions and indexes: U.S. Geological Survey, Geologic Radon Potential Map (2025). Shares: Radon411, from the map cut to the boundary.
Benton County beside the ground around it
On high-potential ground Benton County is close to Iowa as a whole: 100% of its land against 98.8%. Of the 7 counties that border it, none has as large a share of high-potential ground; Black Hawk County comes nearest at 100%.
The map rates the ground, not the air in any home.
Local help
Benton County, Local resources
Radon testing and mitigation in Benton County
Listed radon businesses with an address in Benton County:
- Iowa HHS Radon ProgramIowa HHS Radon Program, run by Iowa Department of Health and Human Services, licenses or certifies radon professionals, offers free or discounted test kits and states the rule for disclosing radon when a home is sold, and answers questions about testing and mitigation in Iowa.Visit the program’s page(opens in a new tab)
- Free and low-cost kitsThe program says:
You can reach the Hotline by calling 1-800-383-5992 to order low-cost radon test kits and find answers to your radon questions.
- Compare kits
- Professionals in Iowa185 professionals are listed in Iowa.
Listed radon professionals by town: Vinton, Shellsburg
What Iowa's program says
- Phone
- (515) 281-4928
- Licensing of radon professionals
Iowa’s radon program approves applications for persons who wish to become certified to perform radon testing or credentialed to perform mitigation and laboratories that provide radon testing devices and analytical services.
- Disclosure when a home is sold or rented
However, per Iowa Code chapters 543B.9 and 543B.18 and Iowa Administrative Code 193E Chapter 14 administered by the Iowa Real Estate Commission, a seller must disclose any known tests for the presence of radon and if yes, provide the date of last report and the result(s).
What it means
Benton County, Questions
Questions about radon in Benton County
Are radon levels high in Benton County?
Over the 2008 to 2017 laboratory totals, 62.1% of the radon tests reported to CDC for Benton County, Iowa were at or above 4 pCi/L, and the median reported pre-mitigation result was 5.6 pCi/L. Of 99 Iowa counties with 30 or more tests for the same period, 56 reported a higher share; pooled, the state comes to 58.5%.
Which counties border Benton County?
Benton County borders 7 counties: Linn County, Tama County, Black Hawk County, Iowa County, Buchanan County, Johnson County and Poweshiek County.
Products
Benton County, Products
Testing a home in Benton County
In Benton County, 62.1% of 696 tests reported to CDC over the 2008 to 2017 laboratory totals reached 4 pCi/L, against 58.5% pooled across Iowa. In Zone 1 the year-round level in Benton 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 monitorMonitorSafetySiren
Pro4 plug-in radon detector with a display and alarm
- C-NRPP 2024/25: Not included
- Plug-in
- Alarm
- Screen
First reading: Within 48 hours
Short-term kit
Radon Short Term Test Kit short-term charcoal radon test kit, lab fee included
- Lab fee included
Method: Charcoal
In home: 2 to 7 days
- See every kit and monitor Test kits and monitors
Test kits and monitors: 1 of 3
Benton County is in EPA Zone 1, the highest predicted radon potential. Best radon monitors for Zone 1 counties like Benton County
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Benton County, Bordering counties
Counties bordering Benton County
Calculated by Radon411- Radon levels in Poweshiek CountyEPA zone 1
70.6%at or above 4 pCi/L
Median 7.2 pCi/L · 419 tests · 8.5 points above Benton County
- Radon levels in Tama CountyEPA zone 1
67.9%at or above 4 pCi/L
Median 7.0 pCi/L · 333 tests · 5.8 points above Benton County
- Radon levels in Iowa CountyEPA zone 1
59.2%at or above 4 pCi/L
Median 5.1 pCi/L · 519 tests · 2.9 points below Benton County
- Radon levels in Buchanan CountyEPA zone 1
51.2%at or above 4 pCi/L
Median 4.1 pCi/L · 564 tests · 10.9 points below Benton County
- Radon levels in Black Hawk CountyEPA zone 1
48.4%at or above 4 pCi/L
Median 3.8 pCi/L · 3,223 tests · 13.7 points below Benton County
- Radon levels in Johnson CountyEPA zone 1
41.6%at or above 4 pCi/L
Median 3.2 pCi/L · 7,321 tests · 20.5 points below Benton County
- Radon levels in Linn CountyEPA zone 1
39.7%at or above 4 pCi/L
Median 3.0 pCi/L · 9,395 tests · 22.4 points below Benton County
Benton County, Cities and towns
Cities and towns in Benton County
The Census Bureau estimates 26,004 residents in Benton County for July 1, 2025, 452 more than in 2020 (+1.8%). That works out to 36 people per square mile of land. No town dominates: Vinton, the largest, has 5,004 residents, 19.2% of the total. CDC's 696 reported tests for 2008 to 2017 work out to 26.8 per 1,000 residents (2025 estimate), close to Iowa's 29.4.
From Vinton to Luzerne, CDC publishes no figure by town: each reads Benton County's.
| Place | Residents | Since 2020 | Share of residents |
|---|---|---|---|
| Vinton | 5,004 | +1.6% | 19.2% |
| Belle Plaine | 2,346 | +0.9% | 9.0% |
| Atkins | 2,203 | +6.8% | 8.5% |
| Urbana | 1,671 | +6.8% | 6.4% |
| Walfordextends beyond Benton County | 1,359 | −0.4% | Counted whole |
| Shellsburg | 997 | +3.6% | 3.8% |
| Newhall | 906 | +3.0% | 3.5% |
| Van Horne | 769 | −0.3% | 3.0% |
| Blairstown | 709 | Level | 2.7% |
| Keystone | 617 | +2.5% | 2.4% |
| Norway | 470 | +1.1% | 1.8% |
| Garrison | 353 | +0.9% | 1.4% |
- Mount Auburn
- Luzerne
14 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 Benton County is counted whole, so it has no share.
Benton County, Homes
Homes in Benton County
Benton County is a place of houses on their own lots: 88% of its 11,095 homes are detached single-family houses, against 72% across Iowa. Half of its homes were built before 1965, close to Iowa's 1971: 46% date from before 1960 and 16% from 2000 or later. Owners live in 84% of the occupied homes (Iowa: 72%), so for most households a test and a fix are their own to order.
| Homes | Benton County | Iowa |
|---|---|---|
| Housing units | 11,095 | 1,427,175 |
| Detached houses | 88% | 72% |
| In buildings of 5 or more | 5% | 14% |
| Mobile homes | 3% | 3% |
| Built before 1960 | 46% | 39% |
| Built since 2000 | 16% | 21% |
| Middle year built | 1965 | 1971 |
| Owner-occupied | 84% | 72% |
Census Bureau, American Community Survey, 2019 to 2023: estimates from a sample of homes, looser for a small place. Shares by Radon411.