Short-term kit
RA400 short-term liquid scintillation radon test kit, lab fee included
- Lab fee included
Method: Liquid scintillation
In home: 48 to 96 hours
Locations and reports
Radon Levels in Marion County, Alabama
EPA puts Marion County in Zone 2, its middle radon zone, and only 25 radon tests from it are on file with CDC (2008 to 2017, laboratory totals). Homes with elevated levels occur in all three zones, so only a test measures yours.
Data checked By Radon411Methodology
Highest bordering
18.1%
Franklin County
- Franklin
- 18.1%
1 of 7 neighbours have 30+ tests, 2008 to 2017
Nearest county
18.1%
Franklin County, 21 miles
- Franklin
- 18.1%
- Alabama
- 21.9%
Share at 4+ pCi/L, 193 tests, 2008 to 2017
Ground above low
99.8%
35.1 pts above Alabama
- Marion
- 99.8%
- Alabama
- 64.7%
Share of land USGS rates moderate or high potential
Tests reported
28
Too few for a share
- Marion
- 28
- Needed
- 30
2006 to 2015, laboratory
EPA radon zone
Zone 2
Moderate potential
- 1
- Zone 2
- 3
1 highest, 3 lowest
EPA predicts 2 to 4 pCi/L indoors
Read a result for Marion County
Starts at EPA's action level
EPA’s own thresholds; the figures are the area’s, never this home’s.
EPA’s reading of 4.0 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.
The data
Marion County, At a glance
Marion County at a glance
Predicted: EPA radon zone
EPA Zone 2: moderate predicted potential
Marion County is a
USGS geologic potential: Moderate across 100% of the county's area
Predicted: EPA Map of Radon Zones
Measured: tests reported to CDC
Radon tests reported for Marion County, 2008 to 2017, laboratory
CDC holds 25 reported tests for Marion County over the 2008 to 2017 laboratory totals, with a median of 1.0 pCi/L: too few to describe a county (Radon411 reads a share from 30 tests up). Marion County beside the counties around it is how this page reads it.
What these figures count
Only 25 tests were reported to CDC for Marion County over 2008 to 2017 (laboratory totals), and tests are often run on homes being sold or already suspected of a problem: so few describe neither the county nor this house.
Measured: CDC tracking data. Figure above: 2008 to 2017, laboratory. Measured data period: 2005 to 2017 (every CDC figure on file).
Marion County, Compared
Marion County radon figures, compared
Calculated by Radon411CDC's largest figure for Marion County rests on 28 tests over the 2006 to 2015 laboratory totals, 2 of them at or above 4 pCi/L, so each test moves its share by 3.6 points and no rank or comparison is drawn from it. Results reached as high as 5.1 pCi/L, with a middle value of 1.2 pCi/L.
Franklin County, the one bordering county with a figure over the 2008 to 2017 laboratory totals, reported 18.1% of its tests at or above 4 pCi/L. Farther out, Colbert County (39 miles away) at 36.2%, Lawrence County (42 miles away) at 16.2% and Lauderdale County (54 miles away) at 27.2% have figures too. Pooled across 65 Alabama counties, 21.9% of reported tests reached that level; across every county in the country with a figure, 35.7%.
Statewide for the same period, Colbert County reported the highest share (36.2%) and Baldwin County the lowest (0.0%). EPA's 1993 map puts Marion County in Zone 2, its middle label: a predicted county average between 2 and 4 pCi/L. USGS geology rates 100% of the county's land moderate radon potential.
Pooled shares: Radon411's sum of CDC's county counts for one period.
Marion County, Geology
The ground under Marion County
PredictedMost of the ground under Marion County is one class on USGS's geologic map: 99.8% of its land is moderate radon potential, with 0.2% low. The map puts 58.8% of Marion County in the area it calls Inner Coastal Plain and 41.0% in Appalachian Plateau. USGS gives the first a radon index of 10 and the second 9, both in the moderate band (9 to 11).
| Area | The rock, in USGS's words | Potential | Radon index | Share of land |
|---|---|---|---|---|
| Inner Coastal Plain | Marly sandy clay, chalk, and glauconitic sands. | Moderate | 10 | 58.8% |
| Appalachian Plateau | Limestone, sandstone, carbonaceous shale, coal | Moderate | 9 | 41.0% |
Names, descriptions and indexes: U.S. Geological Survey, Geologic Radon Potential Map (2025). Shares: Radon411, from the map cut to the boundary.
Marion County beside the ground around it
Across Alabama 14.3% of the land is rated high; none of Marion County's is. Of the 7 counties that border it, 1 has more high-potential ground, Franklin County the most at 49.4%.
The map rates the ground, not the air in any home.
Local help
Marion County, Local resources
Radon testing and mitigation in Marion County
- Alabama Radon ProgramAlabama Radon Program, run by Alabama Department of Public Health, answers questions about testing, mitigation and the rules in Alabama.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
- See the Alabama directoryNo professionals are listed in Alabama yet. The state program can point you to registered testers and mitigators.
What Alabama's program says
- Phone
- (334) 290-6244
What it means
Marion County, Questions
Questions about radon in Marion County
Are radon levels high in Marion County?
Over the 2008 to 2017 laboratory totals, 8.0% of the radon tests reported to CDC for Marion County, Alabama were at or above 4 pCi/L, and the median reported pre-mitigation result was 1.0 pCi/L. Franklin County, the one bordering county with a figure over the 2008 to 2017 laboratory totals, reported 18.1% of its tests at or above 4 pCi/L.
Which counties border Marion County?
Marion County borders 7 counties: Franklin County, AL, Itawamba County, MS, Lamar County, AL, Fayette County, AL, Winston County, AL, Monroe County, MS and Walker County, AL.
Products
Marion County, Products
Testing a home in Marion County
No CDC figure names Marion County; the nearest county with one, Franklin County (21 miles away), reported 18.1% of its tests at or above 4 pCi/L over the 2008 to 2017 laboratory totals, the only reading nearby until a test of this home. In Zone 2 a short-term kit (2 to 90 days) is the quick first check in Marion 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
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
- See every kit and monitor Test kits and monitors
Test kits and monitors: 1 of 3
Explore
Marion County, Bordering counties
Counties bordering Marion County
Calculated by Radon411- Radon levels in Lamar County, ALEPA zone 2
75.0%at or above 4 pCi/L
Median 7.5 pCi/L · 4 tests
- Radon levels in Walker County, ALEPA zone 2
33.3%at or above 4 pCi/L
Median 1.4 pCi/L · 15 tests
- Radon levels in Franklin County, ALEPA zone 1
18.1%at or above 4 pCi/L
Median 1.4 pCi/L · 193 tests
- Radon levels in Winston County, ALEPA zone 2
16.7%at or above 4 pCi/L
Median 1.6 pCi/L · 12 tests
- Radon levels in Fayette County, ALEPA zone 2
0.0%at or above 4 pCi/L
Median 1.1 pCi/L · 2 tests
- Radon levels in Itawamba County, MSEPA zone 3
No CDC figure for 2008 to 2017; its page reads it against its own neighbours.
- Radon levels in Monroe County, MSEPA zone 3
No CDC figure for 2008 to 2017; its page reads it against its own neighbours.
Marion County, Cities and towns
Cities and towns in Marion County
Marion County's population has barely moved since 2020: 29,097 residents on July 1, 2025 against 29,192 then, by the Census Bureau's estimates. That works out to 39 people per square mile of land. Its largest town, Hamilton, has 6,769 residents, 23.3% of the total. Reported testing is thin here: 28 tests over 2006 to 2015, or 1.0 for every 1,000 residents (2025 estimate), where Alabama as a whole comes to 2.6.
From Hamilton to Gu-Win, CDC publishes no figure by town: each reads Marion County's.
| Place | Residents | Since 2020 | Share of residents |
|---|---|---|---|
| Hamilton | 6,769 | −2.5% | 23.3% |
| Winfieldextends beyond Marion County | 4,842 | −0.5% | Counted whole |
| Haleyvilleextends beyond Marion County | 4,303 | −1.0% | Counted whole |
| Guin | 2,136 | −2.9% | 7.3% |
| Hackleburg | 1,465 | +2.2% | 5.0% |
| Bear Creek | 1,054 | +1.6% | 3.6% |
| Brilliant | 838 | +1.1% | 2.9% |
| Glen Allenextends beyond Marion County | 421 | −1.6% | Counted whole |
| Twin | 351 | −0.6% | 1.2% |
| Gu-Winextends beyond Marion County | 135 | −2.2% | Counted whole |
10 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). A place that extends beyond Marion County is counted whole, so it has no share.
Marion County, Homes
Homes in Marion County
Of Marion County's 14,156 homes, 63% are detached houses, against 69% across Alabama; 22% are mobile homes. Half of its homes were built before 1978, close to Alabama's 1985: 16% date from before 1960 and 14% from 2000 or later. Owners live in 75% of the occupied homes (Alabama: 70%), so for most households a test and a fix are their own to order.
| Homes | Marion County | Alabama |
|---|---|---|
| Housing units | 14,156 | 2,316,192 |
| Detached houses | 63% | 69% |
| In buildings of 5 or more | 4% | 12% |
| Mobile homes | 22% | 13% |
| Built before 1960 | 16% | 16% |
| Built since 2000 | 14% | 27% |
| Middle year built | 1978 | 1985 |
| Owner-occupied | 75% | 70% |
Census Bureau, American Community Survey, 2019 to 2023: estimates from a sample of homes, looser for a small place. Shares by Radon411.