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 Fayette County, Iowa
EPA puts Fayette County in Zone 1, its highest radon zone, and high results are common there: 62.7% of the 746 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
62.7%
4.2 pts above IA
- Fayette
- 62.7%
- Iowa
- 58.5%
746 tests, 2008 to 2017
Median result
5.6pCi/L
Action level reached
- Fayette
- 5.6 pCi/L
- EPA
- 4.0 pCi/L
Midpoint of the tests, 2008 to 2017
Tests reported
746
31st of 99 by tests
- Fayette
- 746
- 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
54 of 99
Middle half
- Fayette
- 62.7%
- Sioux
- 84.2%
By share, of 99 with 30+ tests
Read a result for Fayette County
Starts at Fayette 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. Fayette County's median reported result, 2008 to 2017.
The data
Fayette County, At a glance
Fayette County at a glance
Predicted: EPA radon zone
EPA Zone 1: highest predicted potential
EPA puts all of Fayette 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 Fayette County, 2008 to 2017, laboratory
Under 2 pCi/L: 17%2 to 4 pCi/L: 20%4 pCi/L and above: 63%
Of 746 pre-mitigation tests reported to CDC, not homes in this area.
| Result band | Tests Measured | Share Measured |
|---|---|---|
| Under 2 pCi/L | 130 | 17.4% |
| 2 to 4 pCi/L | 148 | 19.8% |
| 4 pCi/L and above | 468 | 62.7% |
What these figures count
These are the 746 tests reported to CDC for Fayette 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).
Fayette County, Compared
Fayette County radon figures, compared
Calculated by Radon411More than half: 62.7% of the 746 radon tests reported to CDC for Fayette County over the 2008 to 2017 laboratory totals read at least 4 pCi/L. That places it 54th of 99 Iowa counties with 30 or more tests for the same period. That is 4.2 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 79.4 pCi/L. The rest split 17.4% under 2 pCi/L and 19.8% from 2 to 4 (Iowa: 21.8% and 19.7%). Zone 1 on EPA's map (predicted average above 4 pCi/L) and a 62.7% share point the same way here.
2 of its 8 bordering counties with figures ran higher, led by Allamakee County at 73.2%; Black Hawk County reported 48.4%. 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 Fayette County went from 690 tests (2005 to 2014) to 746 (2008 to 2017), the share going from 65.4% to 62.7%.
Nationally, every county with a figure for the same period pools to 35.7%; Fayette County sits 27.0 points above it. CDC also counts 48 tests taken after mitigation in Fayette 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.
Fayette County, Geology
The ground under Fayette County
PredictedUSGS's geologic map puts all of Fayette County's mapped land in one class: high radon potential. The map puts 72.4% of Fayette County in the area it calls Iowan Surface and 27.6% in Paleozoic Plateau. 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 | 72.4% |
| Paleozoic Plateau | Ordovician carbonate and Cambrian sandstone bedrock covered by varying amounts of Quaternary glacial deposits and loess. | High | 13 | 27.6% |
Names, descriptions and indexes: U.S. Geological Survey, Geologic Radon Potential Map (2025). Shares: Radon411, from the map cut to the boundary.
Fayette County beside the ground around it
On high-potential ground Fayette County is close to Iowa as a whole: 100% of its land against 98.8%. Of the 8 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
Fayette County, Local resources
Radon testing and mitigation in Fayette County
Listed radon businesses with an address in Fayette 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: Elgin
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
Fayette County, Questions
Questions about radon in Fayette County
Are radon levels high in Fayette County?
Over the 2008 to 2017 laboratory totals, 62.7% of the radon tests reported to CDC for Fayette 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, 53 reported a higher share; pooled, the state comes to 58.5%.
Which counties border Fayette County?
Fayette County borders 8 counties: Buchanan County, Bremer County, Clayton County, Chickasaw County, Delaware County, Black Hawk County, Winneshiek County and Allamakee County.
Products
Fayette County, Products
Testing a home in Fayette County
In Fayette County, 62.7% of 746 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 Fayette 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
MonitorAEGTEST
HOUND-3786 rechargeable radon monitor with a 3.5-inch color screen
- C-NRPP 2024/25: Not included
- Battery
- Alarm
- Screen
Method: Ion chamber
First reading: Within 10 minutes
Short-term kitFirst Alert
RD1 short-term charcoal radon test kit
- Lab fee included
Method: Charcoal
In home: 2 to 4 days
- See every kit and monitor Test kits and monitors
Test kits and monitors: 1 of 3
Fayette County is in EPA Zone 1, the highest predicted radon potential. Best radon monitors for Zone 1 counties like Fayette County
Explore
Fayette County, Bordering counties
Counties bordering Fayette County
Calculated by Radon411- Radon levels in Allamakee CountyEPA zone 1
73.2%at or above 4 pCi/L
Median 7.0 pCi/L · 492 tests · 10.5 points above Fayette County
- Radon levels in Winneshiek CountyEPA zone 1
66.4%at or above 4 pCi/L
Median 6.2 pCi/L · 1,071 tests · 3.7 points above Fayette County
- Radon levels in Clayton CountyEPA zone 1
62.6%at or above 4 pCi/L
Median 5.8 pCi/L · 310 tests · 0.1 points below Fayette County
- Radon levels in Chickasaw CountyEPA zone 1
59.0%at or above 4 pCi/L
Median 4.9 pCi/L · 498 tests · 3.7 points below Fayette County
- Radon levels in Bremer CountyEPA zone 1
53.0%at or above 4 pCi/L
Median 4.3 pCi/L · 957 tests · 9.7 points below Fayette County
- Radon levels in Buchanan CountyEPA zone 1
51.2%at or above 4 pCi/L
Median 4.1 pCi/L · 564 tests · 11.5 points below Fayette County
- Radon levels in Delaware CountyEPA zone 1
50.0%at or above 4 pCi/L
Median 4.0 pCi/L · 520 tests · 12.7 points below Fayette 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 · 14.3 points below Fayette County
Fayette County, Cities and towns
Cities and towns in Fayette County
About 19,047 people live in Fayette County by the Census Bureau's estimate for July 1, 2025, 401 fewer than in 2020 (−2.1%). That works out to 26 people per square mile of land. Its largest town, Oelwein, has 5,757 residents, 30.2% of the total. CDC's 746 reported tests for 2008 to 2017 work out to 39.2 per 1,000 residents (2025 estimate), close to Iowa's 29.4.
From Oelwein to Randalia, CDC publishes no figure by town: each reads Fayette County's.
| Place | Residents | Since 2020 | Share of residents |
|---|---|---|---|
| Oelwein | 5,757 | −2.6% | 30.2% |
| West Union | 2,424 | −2.1% | 12.7% |
| Sumnerextends beyond Fayette County | 2,022 | −0.3% | Counted whole |
| Fayette | 1,185 | −5.5% | 6.2% |
| Fairbankextends beyond Fayette County | 1,145 | +3.2% | Counted whole |
| Elgin | 670 | −2.3% | 3.5% |
| Clermont | 568 | −1.6% | 3.0% |
| Maynard | 462 | −2.3% | 2.4% |
| Hawkeye | 427 | −2.7% | 2.2% |
| Arlington | 414 | −1.4% | 2.2% |
| Waucoma | 238 | +1.7% | 1.2% |
| Wadena | 204 | −1.4% | 1.1% |
- Westgate
- St. Lucas
- Stanley (part)
- Randalia
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 Fayette County is counted whole, so it has no share.
Fayette County, Homes
Homes in Fayette County
Fayette County is a place of houses on their own lots: 85% of its 9,324 homes are detached single-family houses, against 72% across Iowa. The homes are older than Iowa's as a whole: half were built before 1953 (1971 for Iowa), and 56% date from before 1960. Owners live in 77% of the occupied homes (Iowa: 72%), so for most households a test and a fix are their own to order.
| Homes | Fayette County | Iowa |
|---|---|---|
| Housing units | 9,324 | 1,427,175 |
| Detached houses | 85% | 72% |
| In buildings of 5 or more | 4% | 14% |
| Mobile homes | 5% | 3% |
| Built before 1960 | 56% | 39% |
| Built since 2000 | 10% | 21% |
| Middle year built | 1953 | 1971 |
| Owner-occupied | 77% | 72% |
Census Bureau, American Community Survey, 2019 to 2023: estimates from a sample of homes, looser for a small place. Shares by Radon411.