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 Brewster County, Texas
EPA puts Brewster County in Zone 2, its middle radon zone, and only 4 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
Nearest county
1.0%
Midland County, 159 miles
- Midland
- 1.0%
- Texas
- 10.4%
Share at 4+ pCi/L, 100 tests, 2007 to 2016
Ground above low
87.2%
59.9 pts above Texas
- Brewster
- 87.2%
- Texas
- 27.3%
Share of land USGS rates moderate or high potential
Tests reported
5
Too few for a share
- Brewster
- 5
- 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 Brewster 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
Brewster County, At a glance
Brewster County at a glance
Predicted: EPA radon zone
EPA Zone 2: moderate predicted potential
Brewster County is a
USGS geologic potential: Moderate across 87% of the county's area
Predicted: EPA Map of Radon Zones
Measured: tests reported to CDC
Radon tests reported for Brewster County, 2008 to 2017, laboratory
CDC holds 4 reported tests for Brewster County over the 2008 to 2017 laboratory totals, with a median of 3.0 pCi/L: too few to describe a county (Radon411 reads a share from 30 tests up). Brewster County beside the counties around it is how this page reads it.
What these figures count
Only 4 tests were reported to CDC for Brewster 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).
Brewster County, Compared
Brewster County radon figures, compared
Calculated by Radon411CDC's largest figure for Brewster County rests on 5 tests over the 2006 to 2015 laboratory totals, 2 of them at or above 4 pCi/L, so each test moves its share by 20.0 points and no rank or comparison is drawn from it. Results reached as high as 6.1 pCi/L, with a middle value of 1.9 pCi/L.
The nearest counties with a figure are Midland County (159 miles away) at 1.0%, El Paso County (223 miles away) at 0.0% and Lubbock County (275 miles away) at 57.8%. Pooled across 140 Texas counties, 10.4% of reported tests reached that level; across every county in the country with a figure, 35.8%.
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 Brewster County in Zone 2, its middle label: a predicted county average between 2 and 4 pCi/L. USGS geology rates 87% of the county's land moderate radon potential.
Pooled shares: Radon411's sum of CDC's county counts for one period.
Brewster County, Geology
The ground under Brewster County
PredictedMost of the ground under Brewster County is one class on USGS's geologic map: 87.2% of its land is moderate radon potential, with 12.7% low. The map puts 87.1% of Brewster County in the area it calls Western Mountains and Basins and 12.7% in Southern High Plains and Plateaus. USGS gives the first a radon index of 9, 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 |
|---|---|---|---|---|
| Western Mountains and Basins | Precambrian igneous rocks, silicic volcanic rocks, and alluvium. | Moderate | 9 | 87.1% |
| Southern High Plains and Plateaus | Paleozoic and Mesozoic sandstone, limestone, shale. | Low | 7 | 12.7% |
Names, descriptions and indexes: U.S. Geological Survey, Geologic Radon Potential Map (2025). Shares: Radon411, from the map cut to the boundary.
Brewster County beside the ground around it
Across Texas 0.5% of the land is rated high; none of Brewster County's is. Of the 4 counties that border it, 2 have more moderate-potential ground, Jeff Davis County the most at 100%.
The map rates the ground, not the air in any home.
Local help
Brewster County, Local resources
Radon testing and mitigation in Brewster 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
Brewster County, Questions
Questions about radon in Brewster County
Are radon levels high in Brewster County?
Over the 2008 to 2017 laboratory totals, 50.0% of the radon tests reported to CDC for Brewster County, Texas were at or above 4 pCi/L, and the median reported pre-mitigation result was 3.0 pCi/L. Of the 8 nearest counties with a figure, within 364 miles, the share of tests at or above 4 pCi/L runs from 0.0% to 71.4%.
Which counties border Brewster County?
Brewster County borders 4 counties: Terrell County, Pecos County, Presidio County and Jeff Davis County.
Products
Brewster County, Products
Testing a home in Brewster County
No CDC figure names Brewster County; the nearest county with one, Midland County (159 miles away), reported 1.0% 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. In Zone 2 a short-term kit (2 to 90 days) is the quick first check in Brewster 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
Monitor
RadonPro Wi-Fi radon monitor with a built-in Geiger counter
- C-NRPP 2024/25: Not included
- Plug-in
- Wi-Fi
- Alarm
- Screen, app
First reading: Within 5 minutes
- See every kit and monitor Test kits and monitors
Test kits and monitors: 1 of 3
Explore
Brewster County, Bordering counties
Counties bordering Brewster County
Calculated by Radon411- Radon levels in Jeff Davis CountyEPA zone 2
28.6%at or above 4 pCi/L
Median 1.1 pCi/L · 7 tests
- Radon levels in Terrell CountyEPA zone 2
No CDC figure for 2007 to 2016; its page reads it against its own neighbours.
- Radon levels in Pecos CountyEPA zone 3
No CDC figure for 2007 to 2016; its page reads it against its own neighbours.
- Radon levels in Presidio CountyEPA zone 2
No CDC figure for 2007 to 2016; its page reads it against its own neighbours.
Brewster County, Cities and towns
Cities and towns in Brewster County
About 9,458 people live in Brewster County by the Census Bureau's estimate for July 1, 2025, 103 fewer than in 2020 (−1.1%). Spread over its land, that is 1.5 people to the square mile. Alpine, its one incorporated place, has 5,989 residents, 63.3% of the total. Testing is reported here more often than across the state: CDC's 5 reported tests for 2006 to 2015 come to 0.5 for every 1,000 residents (2025 estimate), against 0.1 for Texas.
Alpine is the one incorporated place here; CDC publishes no figure by town, so it reads Brewster County's.
| Place | Residents | Since 2020 | Share of residents |
|---|---|---|---|
| Alpine | 5,989 | −0.6% | 63.3% |
One incorporated place, 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).
Brewster County, Homes
Homes in Brewster County
Of Brewster County's 5,955 homes, 70% are detached houses, against 65% across Texas; 16% are mobile homes. The homes are older than Texas' as a whole: half were built before 1981 (1990 for Texas), and 22% date from before 1960. 57% 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 | Brewster County | Texas |
|---|---|---|
| Housing units | 5,955 | 11,890,808 |
| Detached houses | 70% | 65% |
| In buildings of 5 or more | 8% | 21% |
| Mobile homes | 16% | 7% |
| Built before 1960 | 22% | 13% |
| Built since 2000 | 33% | 37% |
| Middle year built | 1981 | 1990 |
| Owner-occupied | 57% | 63% |
Census Bureau, American Community Survey, 2019 to 2023: estimates from a sample of homes, looser for a small place. Shares by Radon411.