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
Locations and reports
Radon Levels in Alger County, Michigan
EPA puts Alger County in Zone 2, its middle radon zone, and 16.4% of its 189 reported radon tests (2008 to 2017, laboratory totals) were 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
16.4%
10.5 pts below MI
- Alger
- 16.4%
- Michigan
- 26.9%
189 tests, 2008 to 2017
Median result
1.2pCi/L
Below action level
- Alger
- 1.2 pCi/L
- EPA
- 4.0 pCi/L
Midpoint of the tests, 2008 to 2017
Tests reported
189
68th of 82 by tests
- Alger
- 189
- Oakland
- 16,224
Reported to CDC before any fix, 2008 to 2017
EPA radon zone
Zone 2
Moderate potential
- 1
- Zone 2
- 3
1 highest, 3 lowest
EPA predicts 2 to 4 pCi/L indoors
Rank in Michigan
46 of 82
Middle half
- Alger
- 16.4%
- Lenawee
- 56.7%
By share, of 82 with 30+ tests
Read a result for Alger County
Starts at Alger County's median, 1.2 pCi/L
EPA’s own thresholds; the figures are the area’s, never this home’s.
EPA’s reading of 1.2 pCi/L
Below 2 pCi/L
- Under 20 to 1.9 pCi/L
- 2 to 4consider a fix
- 4 and aboveEPA says fix it
This result is below 2 pCi/L, the level at which EPA says a fix should be considered. Alger County's median reported result, 2008 to 2017.
The data
Alger County, At a glance
Alger County at a glance
Predicted: EPA radon zone
EPA Zone 2: moderate predicted potential
Alger County is a
USGS geologic potential: Moderate across 76% of the county's area
Predicted: EPA Map of Radon Zones
Measured: tests reported to CDC
Radon tests reported for Alger County, 2008 to 2017, laboratory
Under 2 pCi/L: 68%2 to 4 pCi/L: 16%4 pCi/L and above: 16%
Of 189 pre-mitigation tests reported to CDC, not homes in this area.
| Result band | Tests Measured | Share Measured |
|---|---|---|
| Under 2 pCi/L | 128 | 67.7% |
| 2 to 4 pCi/L | 30 | 15.9% |
| 4 pCi/L and above | 31 | 16.4% |
What these figures count
These are the 189 tests reported to CDC for Alger 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).
Alger County, Compared
Alger County radon figures, compared
Calculated by Radon411Alger County's 189 reported tests over the 2008 to 2017 laboratory totals had a middle value of 1.2 pCi/L and a maximum of 12.3 pCi/L, and 16.4% reached 4 pCi/L. Michigan as a whole (83 Michigan counties, pooled) comes to 26.9%: 10.5 points higher than here.
Among its state's counties it ranks 46th of 82 Michigan counties with 30 or more tests for the same period. Statewide for the same period, Lenawee County reported the highest share (56.7%) and Muskegon County the lowest (3.2%).
Below the action level, 128 tests (67.7%) came in under 2 pCi/L, against 46.4% statewide, and 30 tests (15.9%) fell between 2 and 4, against 26.7% statewide. CDC's ten-year totals for Alger County went from 244 tests (2005 to 2014) to 189 (2008 to 2017), the share going from 11.9% to 16.4%.
EPA's 1993 zone map puts Alger County in Zone 2, a predicted county average between 2 and 4 pCi/L. USGS geology rates 76% of the county's land moderate radon potential.
Next door, the shares run from 15.2% in Schoolcraft County to 23.4% in Marquette County, with Schoolcraft County below Alger County.
Pooled shares: Radon411's sum of CDC's county counts for one period.
Alger County, State data
Michigan's own radon test data
MeasuredWhat Michigan's own agencies publish about radon tests in Alger County, with their period. These are not CDC's figures and are never added to them.
MeasuredState figures, not CDC's
What Michigan EGLE reports for the ZIP codes in Alger County
Michigan EGLE publishes its figures by ZIP code, not by county. These are the 12 ZIP codes that lie wholly or partly in Alger County, each with the state's own figures for it. Period: About 10 years to 2026-05-15.
| ZIP code | What the state reports |
|---|---|
| 49806 | 0% greater than 4 pCi/L, median 1.0 pCi/L, 9 tests |
| 49816 | 18% greater than 4 pCi/L, median 2.2 pCi/L, 11 tests |
| 49822 | 1 tests, figures not shown |
| 49825 | 2 tests, figures not shown |
| 49839 | 4 tests, figures not shown |
| 49862 | 17% greater than 4 pCi/L, median 0.9 pCi/L, 36 tests |
| 49878 | 8% greater than 4 pCi/L, median 1.6 pCi/L, 60 tests |
| 49883 | 1 tests, figures not shown |
| 49884 | 3 tests, figures not shown |
| 49885 | 17% greater than 4 pCi/L, median 1.9 pCi/L, 12 tests |
| 49891 | 25% greater than 4 pCi/L, median 1.7 pCi/L, 8 tests |
| 49895 | 29% greater than 4 pCi/L, median 1.5 pCi/L, 14 tests |
- EGLE's figures cover first-time tests only, from organizations willing to provide data.
- EGLE does not publish figures for a ZIP code with fewer than 5 test results.
- EGLE says the map is not intended to decide whether a home should be tested: all homes should be tested.
- ZIP code boundaries are postal delivery areas, not legal or administrative boundaries.
- A ZIP code that crosses the county line is listed whole; its figures cover all of it.
Measured: Michigan EGLE data, About 10 years to 2026-05-15.
Alger County, Geology
The ground under Alger County
PredictedMost of the ground under Alger County is one class on USGS's geologic map: 75.9% of its land is moderate radon potential, with 21.6% low. The map puts 75.9% of Alger County in the area it calls Outer Michigan Basin and 21.6% in Glacial Lakes. USGS gives the first a radon index of 10, in the moderate band (9 to 11), and the second 7, in the low band (5 to 8).
| Area | The rock, in USGS's words | Potential | Radon index | Share of land |
|---|---|---|---|---|
| Outer Michigan Basin | Glacial deposits derived from Paleozoic carbonate rocks and sandstones. | Moderate | 10 | 75.9% |
| Glacial Lakes | Silt and clay glacial lake deposits. | Low | 7 | 21.6% |
Names, descriptions and indexes: U.S. Geological Survey, Geologic Radon Potential Map (2025). Shares: Radon411, from the map cut to the boundary.
Alger County beside the ground around it
Across Michigan 9.6% of the land is rated high; none of Alger County's is. Of the 4 counties that border it, 1 has more moderate-potential ground, Marquette County the most at 99.9%.
The map rates the ground, not the air in any home.
Local help
Alger County, Local resources
Radon testing and mitigation in Alger County
- Michigan Indoor Radon ProgramMichigan Indoor Radon Program, run by Michigan Department of Environment, Great Lakes, and Energy, does not license radon professionals, and answers questions about testing and mitigation in Michigan.Visit the program’s page(opens in a new tab)
- Free and low-cost kitsAsk the program whether it has free or discounted kits, or compare kits you can buy.
- Compare kits
- Professionals in Michigan69 professionals are listed in Michigan.
What Michigan's program says
- Phone
- 800-723-6642
- Radon@Michigan.gov
- Licensing of radon professionals
Michigan does not license or regulate radon testing and mitigation contractors.
What it means
Alger County, Questions
Questions about radon in Alger County
Are radon levels high in Alger County?
Over the 2008 to 2017 laboratory totals, 16.4% of the radon tests reported to CDC for Alger County, Michigan were at or above 4 pCi/L, and the median reported pre-mitigation result was 1.2 pCi/L. Of 82 Michigan counties with 30 or more tests for the same period, 45 reported a higher share; pooled, the state comes to 26.9%.
Which counties border Alger County?
Alger County borders 4 counties: Schoolcraft County, Delta County, Marquette County and Luce County.
Products
Alger County, Products
Testing a home in Alger County
In Alger County, 16.4% of 189 tests reported to CDC over the 2008 to 2017 laboratory totals reached 4 pCi/L, against 26.9% pooled across Michigan. In Zone 2 a short-term kit (2 to 90 days) is the quick first check in Alger County; a long-term test tells the year-round average.
Test kits and monitors3
See every kit and monitor
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
MonitorKidde
Radon Detector (RAB) battery digital radon detector with an alarm
- C-NRPP 2024/25: Not included
- Battery
- Alarm
- Screen
Method: Semiconductor sensor
First reading: Within 12 hours
- See every kit and monitor Test kits and monitors
Test kits and monitors: 1 of 3
Explore
Alger County, Bordering counties
Counties bordering Alger County
Calculated by Radon411- Radon levels in Marquette CountyEPA zone 2
23.4%at or above 4 pCi/L
Median 2.0 pCi/L · 1,082 tests · 7.0 points above Alger County
- Radon levels in Delta CountyEPA zone 3
21.5%at or above 4 pCi/L
Median 1.7 pCi/L · 711 tests · 5.1 points above Alger County
- Radon levels in Schoolcraft CountyEPA zone 3
15.2%at or above 4 pCi/L
Median 0.6 pCi/L · 66 tests · 1.2 points below Alger County
- Radon levels in Luce CountyEPA zone 3
4.2%at or above 4 pCi/L
Median 1.0 pCi/L · 24 tests · 12.2 points below Alger County
Alger County, Cities and towns
Cities and towns in Alger County
About 8,641 people live in Alger County by the Census Bureau's estimate for July 1, 2025, 204 fewer than in 2020 (−2.3%). Spread over its land, that is 9.4 people to the square mile. Its largest town, Munising, has 1,938 residents, 22.4% of the total. Together its 2 incorporated places hold 24.9% of those residents; the other 75.1% live outside any of them. Testing is reported here more often than across the state: CDC's 189 reported tests for 2008 to 2017 come to 21.9 for every 1,000 residents (2025 estimate), against 11.3 for Michigan.
From Munising to Chatham, CDC publishes no figure by town: each reads Alger County's.
| Place | Residents | Since 2020 | Share of residents |
|---|---|---|---|
| Munising | 1,938 | −1.8% | 22.4% |
| Chatham | 214 | −1.4% | 2.5% |
2 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).
Alger County, Homes
Homes in Alger County
Alger County is a place of houses on their own lots: 85% of its 6,205 homes are detached single-family houses, against 72% across Michigan. Half of its homes were built before 1973, close to Michigan's 1972: 35% date from before 1960 and 15% from 2000 or later. Owners live in 84% of the occupied homes (Michigan: 73%), so for most households a test and a fix are their own to order.
| Homes | Alger County | Michigan |
|---|---|---|
| Housing units | 6,205 | 4,599,683 |
| Detached houses | 85% | 72% |
| In buildings of 5 or more | 4% | 13% |
| Mobile homes | 6% | 5% |
| Built before 1960 | 35% | 36% |
| Built since 2000 | 15% | 15% |
| Middle year built | 1973 | 1972 |
| Owner-occupied | 84% | 73% |
Census Bureau, American Community Survey, 2019 to 2023: estimates from a sample of homes, looser for a small place. Shares by Radon411.