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 Washington County, Mississippi
EPA puts Washington County in Zone 3, its lowest radon zone. Homes with elevated levels occur in all three zones, so only a test measures yours.
Data checked By Radon411Methodology
Nearest county
6.2%
Pulaski County, 129 miles
- Pulaski
- 6.2%
Share at 4+ pCi/L, 97 tests, 2006 to 2015
Ground above low
None
8.1 pts below MS
- Washington
- 0.0%
- MS
- 8.1%
Share of land USGS rates moderate or high potential
Tests reported
0
None published
A home here needs its own test
EPA radon zone
Zone 3
Lower potential
- 1
- 2
- Zone 3
1 highest, 3 lowest
EPA predicts under 2 pCi/L indoors
Read a result for Washington 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
Washington County, At a glance
Washington County at a glance
Predicted: EPA radon zone
EPA Zone 3: lower predicted potential
USGS geologic potential: Low across 100% of the county's area
Predicted: EPA Map of Radon Zones
Measured: tests reported to CDC
No CDC test figures here
CDC has published no radon test figures for Washington County. Pulaski County, AR, 129 miles away, is the nearest county with a figure over the 2006 to 2015 laboratory totals.
Washington County, Compared
Washington County radon figures, compared
Calculated by Radon411Washington County is in a state CDC's county radon counts do not reach: no Mississippi county has a figure, while 2,669 counties elsewhere do over the 2006 to 2015 laboratory totals. Across every county in the country with a figure (2,669), 36.3% of reported tests reached that level; no Mississippi county contributes to that pool.
The nearest counties with a figure are Pulaski County, AR (129 miles away) at 6.2%, Saline County, AR (137 miles away) at 31.9% and Shelby County, TN (144 miles away) at 7.0%.
EPA's 1993 map puts Washington County in Zone 3, its lowest label: a predicted county average under 2 pCi/L. USGS geology rates 100% of the county's land low radon potential.
Pooled shares: Radon411's sum of CDC's county counts for one period.
Washington County, Geology
The ground under Washington County
PredictedUSGS's geologic map puts all of Washington County's mapped land in one class: low radon potential. All of it lies in the area the map calls Mississippi Alluvial Plain, to which USGS gives a radon index of 8, in the low band (5 to 8).
| Area | The rock, in USGS's words | Potential | Radon index | Share of land |
|---|---|---|---|---|
| Mississippi Alluvial Plain | Alluvial sand, silt, gravel, and clay. | Low | 8 | 100% |
Names, descriptions and indexes: U.S. Geological Survey, Geologic Radon Potential Map (2025). Shares: Radon411, from the map cut to the boundary.
Washington County beside the ground around it
Across Mississippi 0.1% of the land is rated high; none of Washington County's is. None of the 6 counties that border it has any moderate-potential ground either.
The map rates the ground, not the air in any home.
Local help
Washington County, Local resources
Radon testing and mitigation in Washington County
- Mississippi Radon ProgramMississippi Radon Program, run by Mississippi State Department of Health, answers questions about testing, mitigation and the rules in Mississippi.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 Mississippi directoryNo professionals are listed in Mississippi yet. The state program can point you to registered testers and mitigators.
What Mississippi's program says
- Phone
- 1-800-626-7739
What it means
Washington County, Questions
Questions about radon in Washington County
Are radon levels high in Washington County?
No CDC testing statistics are published here for Washington County, Mississippi yet. Of the 8 nearest counties with a figure, within 189 miles, the share of tests at or above 4 pCi/L runs from 0.0% to 45.5%.
Which counties border Washington County?
Washington County borders 6 counties: Humphreys County, MS, Chicot County, AR, Sharkey County, MS, Sunflower County, MS, Issaquena County, MS and Bolivar County, MS.
Products
Washington County, Products
Testing a home in Washington County
No CDC figure names Washington County; the nearest county with one, Pulaski County, AR (129 miles away), reported 6.2% of its tests at or above 4 pCi/L over the 2006 to 2015 laboratory totals, the only reading nearby until a test of this home. Zone 3 is the lowest label, yet homes at or above 4 pCi/L occur in every zone: a short-term kit (2 to 90 days) is the quick first check in Washington County.
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
Monitor
Corentium Home 2 battery digital radon monitor
- C-NRPP 2024/25: Not included
- Battery
- Bluetooth
- Screen, app
Method: Alpha spectrometry
Readings: Every 60 minutes
- See every kit and monitor Test kits and monitors
Test kits and monitors: 1 of 3
Explore
Washington County, Bordering counties
Counties bordering Washington County
Calculated by Radon411counties bordering Washington County: 1 of 6
Washington County, Cities and towns
Cities and towns in Washington County
Washington County has been losing residents: from 44,639 in 2020 to 40,446 on July 1, 2025, a fall of 9.4% by the Census Bureau's estimates. That works out to 56 people per square mile of land. Greenville alone is home to 26,530 of them, 65.6% of the total. Together its 5 incorporated places hold 82.1% of those residents; the other 17.9% live outside any of them.
From Greenville to Arcola, CDC publishes no figure by town: each reads Washington County's.
| Place | Residents | Since 2020 | Share of residents |
|---|---|---|---|
| Greenville | 26,530 | −10.1% | 65.6% |
| Leland | 3,555 | −10.0% | 8.8% |
| Hollandale | 2,090 | −9.9% | 5.2% |
| Metcalfe | 735 | −9.8% | 1.8% |
| Arcola | 276 | −8.9% | 0.7% |
5 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).
Washington County, Homes
Homes in Washington County
Of Washington County's 20,894 homes, 72% are detached houses, against 69% across Mississippi; 11% are in buildings of five or more homes. The homes are older than Mississippi's as a whole: half were built before 1973 (1986 for Mississippi), and 26% date from before 1960. 57% of occupied homes are lived in by their owner (Mississippi: 69%); in the rest a tenant can run a test, but a fix is the landlord's to make.
| Homes | Washington County | Mississippi |
|---|---|---|
| Housing units | 20,894 | 1,332,811 |
| Detached houses | 72% | 69% |
| In buildings of 5 or more | 11% | 9% |
| Mobile homes | 8% | 15% |
| Built before 1960 | 26% | 15% |
| Built since 2000 | 8% | 28% |
| Middle year built | 1973 | 1986 |
| Owner-occupied | 57% | 69% |
Census Bureau, American Community Survey, 2019 to 2023: estimates from a sample of homes, looser for a small place. Shares by Radon411.