
MonitorAEGTEST
HOUND-1011 rechargeable radon detector with a screen
- C-NRPP 2024/25: Not included
- Battery
- Alarm
- Screen
Method: Semiconductor sensor
First reading: Within 6 hours
Locations and reports
EPA puts Winona County in Zone 1, its highest radon zone. Homes with elevated levels occur in all three zones, so only a test measures yours.
Data checked By Radon411Methodology
The data
Winona County, At a glance
Predicted: EPA radon zone
This is a county-level geologic prediction. It is not a measurement of any address, and houses with elevated radon are found in all three zones.
EPA predicts an average indoor
USGS geologic potential: High across 100% of the county's area
Predicted: EPA Map of Radon Zones
Measured: tests reported to CDC
Of 139 pre-mitigation tests reported to CDC, not homes in this area.
| Result band | Tests Measured | Share Measured |
|---|---|---|
| Under 2 pCi/L | 43 | 30.9% |
| 2 to 4 pCi/L | 42 | 30.2% |
| 4 pCi/L and above | 54 | 38.8% |
CDC publishes this figure only for counties here, so there is no state or national number to compare Winona County, Minnesota with.
Distribution of radon tests reported to CDC, not this house. People testing before a sale, or because they suspect a problem, are over-represented in any reported testing data.
The figures at the top are for 2023: a percentage there is a share of radon tests reported to CDC for Winona County in 2023, and a percentage in a view below is a share of the tests reported for the year or period it names. It is not a share of homes in Winona County, and it is not a random sample: it counts only the tests people chose to run and that were reported.
CDC works out the shares and the median over pre-mitigation tests, counting a test not marked as before or after mitigation as one of them (139 for 2023). The median is the middle result of those tests, not of buildings. CDC also reports the number of buildings tested (118), a different count, so the two totals are not interchangeable.
Winona County's own published CDC figures beside those of the counties that border it, for the same period.
Each figure is that county’s own published CDC figure for 2023, counting radon tests reported to CDC, not homes. Winona County is this page. Nothing is averaged or combined across counties. The test count beside each county is CDC’s published number of pre-mitigation tests behind its figures. Figures from few tests can swing widely from year to year. Every Minnesota county’s own figure is in the Minnesota county table.
Measured: CDC tracking data. Figure above: 2023. Measured data period: 2005 to 2023 (every CDC figure on file).
Winona County, State data
What Minnesota's own agencies publish about radon tests in Winona County, with their period. These are not CDC's figures and are never added to them.
Radon Testing (MN Public Health Data Access Portal): home radon tests reported voluntarily by private laboratories and licensed radon measurement professionals, counted by property. Period: 2016-2025.
Share with one or more tests at or above 4 pCi/L
41.3%
806 properties tested with one or more tests at or above 4 pCi/L
Median result
3.1 pCi/L
Average result
4.3 pCi/L
Tests behind these figures
195 properties tested a year on average
Measured: Minnesota Department of Health data, 2016-2025.
Radon Action Brief
National Radon Action MonthPre-sale
Save 64%Sale price: $8.99Price after the sale: $25Ends Jan 31Then $25Sale ends January 31, then $25
Local help
Winona County, Local resources
Who tests and fixes radon in Winona County: listed businesses, Minnesota's radon program and test kits.
Listed radon businesses with an address in Winona County:
Listed radon professionals by town: Winona, Altura
The Radon Licensing Act requires anyone who performs a radon test or radon mitigation, in a building they do not own or lease, must be licensed by MDH.
The Minnesota Radon Awareness Act requires specific disclosure and education be provided to potential home buyers during residential real estate transactions in Minnesota.
What it means
Winona County, Questions
EPA says you can test your home yourself or hire a qualified radon test company, and that either approach takes only a small amount of time and effort. No radon testing business listed on Radon411 has an address in Winona County or names it as a service area yet. The Minnesota radon program is the place to ask about certified testers and any test kit offer it runs.
Radon testing: how to test a homeRadon test kits comparedFree and low-cost kits by stateRadon Action Month checklistMinnesota radon program
No listed mitigator names Winona County as a service area yet; the Minnesota directory lists 253 companies. EPA recommends having a qualified contractor fix a home with a radon problem, because lowering high radon levels takes technical knowledge and special skills, and some states require the work to be done by a licensed or certified professional. Your state radon program is the place to check whether Minnesota requires one.
Radon mitigation: how it worksRadon mitigation costRadon mitigation systemsMitigators in Minnesota
In 2023, 38.8% of the radon tests reported to CDC for Winona County, Minnesota were at or above 4 pCi/L, and the median reported pre-mitigation result was 3.0 pCi/L. That is a share of reported tests, not of homes. EPA places Winona County in Zone 1, highest predicted potential, a predicted average indoor screening level greater than 4 pCi/L. Homes with elevated levels occur in all three zones, so the figures describe the area, not your house. Testing is the only way to know the radon level in a specific building.
Radon levels: what a result meansWhat is radon?Radon levels in Minnesota
EPA places Winona County, Minnesota in Zone 1, which EPA describes as highest predicted potential for the area. A zone is a prediction for the whole county and never determines whether a particular home should be tested. EPA recommends testing every home regardless of zone.
Yes. Testing is the only way to know the radon level in a specific building. EPA recommends fixing a home when the radon level is 4 pCi/L or higher. EPA recommends considering a fix when the level is between 2 and 4 pCi/L. How to test a home.
EPA says short-term tests stay in the home from 2 to 90 days and that all radon tests should run a minimum of 48 hours; long-term tests stay more than 90 days. EPA's guides do not name a best season: they say radon levels tend to vary from day to day and season to season, so a long-term test is more likely than a short-term test to tell you the year-round average.
EPA's Citizen's Guide calls testing easy and inexpensive, and EPA's Home Buyer's and Seller's Guide says passive short-term and long-term devices are generally inexpensive, while active devices may cost more. No national average price is published for this, so Radon411 does not give one. What testing costs.
Winona County borders 7 counties, derived from Census county geometry. Radon potential follows geology rather than county lines, so a bordering county's report can be relevant.
The reported-test figures on this page describe Winona County, Minnesota in 2023. They describe tests other people carried out in other buildings, and none of them measures yours.
What the published data says about Winona County, in words. A zone and a share of tests describe an area, never the level in any one home.
EPA places Winona County in Zone 1, highest predicted potential, as it does 67 other counties of Minnesota's 87.
Of the 7 bordering counties, EPA places Buffalo County, WI, Fillmore County, Houston County, Olmsted County and Wabasha County in Zone 1 and La Crosse County, WI and Trempealeau County, WI in Zone 2.
CDC has annual figures for Winona County for 10 years, 2014 to 2023. In 2023, 38.8% of 139 reported tests were at or above 4 pCi/L.
Across those years the share ranged from 21.2% (2020) to 49.0% (2014). Few tests in a year can move it a long way.
Minnesota's radon program is the MDH Indoor Air Unit, run by MN Dept. of Health; its contacts are under Local resources.
The county's largest incorporated places are Winona, La Crescent and Goodview; the figures here cover them as part of the county.
Products
Winona County, Products
Whatever the figures for Winona County show, only a test tells you about one home.
Test kits and monitors: 1 of 42
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Winona County is in EPA Zone 1, the highest predicted radon potential. Best radon monitors for Zone 1 counties like Winona County
Testing: 1 of 5
Mitigation: 1 of 3
Explore
Winona County, Bordering counties
counties bordering Winona County: 1 of 7
7 counties share a boundary with Winona County, computed from Census county geometry. Radon potential follows geology rather than county lines, so a bordering county’s report can be worth reading alongside this one.
Winona County, Cities and towns
The radon figures on this page are for Winona County as a whole. They do not differ by city or town.
13 incorporated places, as listed in the U.S. Census Bureau’s 2020 place reference files. “(part)” marks a place that extends into another county.
Winona County, Next steps
What to do next: 1 of 4
Informational. Follow EPA guidance. EPA says all radon tests should be taken for a minimum of 48 hours, with windows and doors closed from 12 hours before a short-term test.