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 Dimmit County, Texas
EPA puts Dimmit 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
6.6%
Bexar County, 103 miles
- Bexar
- 6.6%
- Texas
- 10.4%
Share at 4+ pCi/L, 197 tests, 2007 to 2016
Ground above low
None
27.3 pts below Texas
- Dimmit
- 0.0%
- Texas
- 27.3%
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 Dimmit 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
Dimmit County, At a glance
Dimmit 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 Dimmit County. Bexar County, 103 miles away, is the nearest county with a figure over the 2007 to 2016 laboratory totals.
Dimmit County, Compared
Dimmit County radon figures, compared
Calculated by Radon411Dimmit County has no radon test figure of its own from CDC, whose counts over the 2007 to 2016 laboratory totals name 140 other Texas counties and leave it out. Pooled across 140 Texas counties, 10.4% of reported tests reached that level; across every county in the country with a figure, 35.8%.
The nearest counties with a figure are Bexar County (103 miles away) at 6.6%, Nueces County (139 miles away) at 0.0% and Travis County (178 miles away) at 9.3%. Statewide for the same period, Randall County reported the highest share (71.4%) and Nueces County the lowest (0.0%).
EPA's 1993 map puts Dimmit 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.
Dimmit County, Geology
The ground under Dimmit County
PredictedUSGS's geologic map puts all of Dimmit County's mapped land in one class: low radon potential. All of it lies in the area the map calls South Texas Plain, to which USGS gives a radon index of 7, in the low band (5 to 8).
| Area | The rock, in USGS's words | Potential | Radon index | Share of land |
|---|---|---|---|---|
| South Texas Plain | Cretaceous through Quaternary marine sandstone, shale, chalk, limestone, siltstone, clay, and lignite. | Low | 7 | 100% |
Names, descriptions and indexes: U.S. Geological Survey, Geologic Radon Potential Map (2025). Shares: Radon411, from the map cut to the boundary.
Dimmit County beside the ground around it
Across Texas 0.5% of the land is rated high; none of Dimmit County's is. None of the 5 counties that border it has any moderate-potential ground either.
The map rates the ground, not the air in any home.
Local help
Dimmit County, Local resources
Radon testing and mitigation in Dimmit County
- Texas Radon GroupTexas Radon Group, run by Texas Tech University, does not license radon professionals and offers free or discounted test kits, and answers questions about testing and mitigation in Texas.Visit the program’s page(opens in a new tab)
- Free and low-cost kitsThe program says:
The Texas Radon Group offers free radon test kits for Texas individuals who qualify.
- Compare kits
- Professionals in Texas7 professionals are listed in Texas.
What Texas's program says
- Licensing of radon professionals
There are no radon certification requirements for the State of Texas at this time, but the National Radon Proficiency Program lists radon testers and mitigators within Texas that have passed a rigorous national certification program.
What it means
Dimmit County, Questions
Questions about radon in Dimmit County
Are radon levels high in Dimmit County?
No CDC testing statistics are published here for Dimmit County, Texas yet. Of the 8 nearest counties with a figure, within 264 miles, the share of tests at or above 4 pCi/L runs from 0.0% to 17.1%.
Which counties border Dimmit County?
Dimmit County borders 5 counties: Zavala County, Maverick County, La Salle County, Frio County and Webb County.
Products
Dimmit County, Products
Testing a home in Dimmit County
No CDC figure names Dimmit County; the nearest county with one, Bexar County (103 miles away), reported 6.6% of its tests at or above 4 pCi/L over the 2007 to 2016 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 Dimmit 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
Dimmit County, Bordering counties
Counties bordering Dimmit County
Calculated by Radon411- Radon levels in Maverick CountyEPA zone 3
0.0%at or above 4 pCi/L
Median 0.1 pCi/L · 2 tests
- Radon levels in Webb CountyEPA zone 3
0.0%at or above 4 pCi/L
Median 0.6 pCi/L · 6 tests
- Radon levels in Zavala CountyEPA zone 3
No CDC figure for 2007 to 2016; its page reads it against its own neighbours.
- Radon levels in La Salle CountyEPA zone 3
No CDC figure for 2007 to 2016; its page reads it against its own neighbours.
- Radon levels in Frio CountyEPA zone 3
No CDC figure for 2007 to 2016; its page reads it against its own neighbours.
Dimmit County, Cities and towns
Cities and towns in Dimmit County
Dimmit County has been losing residents: from 8,584 in 2020 to 8,024 on July 1, 2025, a fall of 6.5% by the Census Bureau's estimates. Spread over its land, that is 6.0 people to the square mile. Carrizo Springs alone is home to 4,491 of them, 56.0% of the total. Together its 3 incorporated places hold 69.8% of those residents; the other 30.2% live outside any of them. CDC publishes no radon test count for Dimmit County; across Texas its counts for 2007 to 2016 come to 0.1 tests for every 1,000 residents (2025 estimate).
From Carrizo Springs to Big Wells, CDC publishes no figure by town: each reads Dimmit County's.
| Place | Residents | Since 2020 | Share of residents |
|---|---|---|---|
| Carrizo Springs | 4,491 | −7.8% | 56.0% |
| Asherton | 659 | −7.7% | 8.2% |
| Big Wells | 448 | −6.7% | 5.6% |
3 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).
Dimmit County, Homes
Homes in Dimmit County
Of Dimmit County's 4,012 homes, 58% are detached houses, against 65% across Texas; 28% are mobile homes. Half of its homes were built before 1983, close to Texas' 1990: 17% date from before 1960 and 30% from 2000 or later. 61% of occupied homes are lived in by their owner (Texas: 63%); in the rest a tenant can run a test, but a fix is the landlord's to make.
| Homes | Dimmit County | Texas |
|---|---|---|
| Housing units | 4,012 | 11,890,808 |
| Detached houses | 58% | 65% |
| In buildings of 5 or more | 3% | 21% |
| Mobile homes | 28% | 7% |
| Built before 1960 | 17% | 13% |
| Built since 2000 | 30% | 37% |
| Middle year built | 1983 | 1990 |
| Owner-occupied | 61% | 63% |
Census Bureau, American Community Survey, 2019 to 2023: estimates from a sample of homes, looser for a small place. Shares by Radon411.