Short-term kit
PicoCan short-term charcoal canister radon test
- Lab fee included
Method: Charcoal
In home: 48 to 96 hours
Locations and reports
Radon Levels in Brown County, Texas
EPA puts Brown County in Zone 3, its lowest radon zone, and only 2 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
14.3%
Bell County, 103 miles
- Bell
- 14.3%
- Texas
- 10.4%
Share at 4+ pCi/L, 35 tests, 2007 to 2016
Ground above low
None
27.3 pts below Texas
- Brown
- 0.0%
- Texas
- 27.3%
Share of land USGS rates moderate or high potential
Tests reported
2
Too few for a share
- Brown
- 2
- Needed
- 30
2008 to 2017, laboratory
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 Brown 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
Brown County, At a glance
Brown 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
Radon tests reported for Brown County, 2008 to 2017, laboratory
CDC holds 2 reported tests for Brown 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). Brown County beside the counties around it is how this page reads it.
What these figures count
Only 2 tests were reported to CDC for Brown 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).
Brown County, Compared
Brown County radon figures, compared
Calculated by Radon411CDC's largest figure for Brown County rests on 2 tests over the 2008 to 2017 laboratory totals, 0 of them at or above 4 pCi/L, so each test moves its share by 50.0 points and no rank or comparison is drawn from it. Results reached as high as 1.8 pCi/L, with a middle value of 1.0 pCi/L.
The nearest counties with a figure are Bell County (103 miles away) at 14.3%, McLennan County (107 miles away) at 17.1% and Williamson County (113 miles away) at 2.0%. 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 Brown 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.
Brown County, Geology
The ground under Brown County
PredictedUSGS's geologic map puts all of Brown County's mapped land in one class: low radon potential. The map puts 68.4% of Brown County in the area it calls Central Texas and 31.6% in Central Texas/Gulf Coast Plain. USGS gives both 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 |
|---|---|---|---|---|
| Central Texas | Cretaceous through Quaternary marine sandstone, shale, chalk, limestone, siltstone, clay, and lignite. | Low | 7 | 68.4% |
| Central Texas/Gulf Coast Plain | Cretaceous through Quaternary marine sandstone, shale, chalk, limestone, siltstone, clay, and lignite. | Low | 7 | 31.6% |
Names, descriptions and indexes: U.S. Geological Survey, Geologic Radon Potential Map (2025). Shares: Radon411, from the map cut to the boundary.
Brown County beside the ground around it
Across Texas 0.5% of the land is rated high; none of Brown County's is. Of the 7 counties that border it, 2 have more moderate-potential ground, San Saba County the most at 47.9%.
The map rates the ground, not the air in any home.
Local help
Brown County, Local resources
Radon testing and mitigation in Brown 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
Brown County, Questions
Questions about radon in Brown County
Are radon levels high in Brown County?
Over the 2008 to 2017 laboratory totals, 0.0% of the radon tests reported to CDC for Brown County, Texas were at or above 4 pCi/L, and the median reported pre-mitigation result was 1.0 pCi/L. Of the 8 nearest counties with a figure, within 163 miles, the share of tests at or above 4 pCi/L runs from 2.0% to 17.1%.
Which counties border Brown County?
Brown County borders 7 counties: Comanche County, Coleman County, Eastland County, Mills County, Callahan County, San Saba County and McCulloch County.
Products
Brown County, Products
Testing a home in Brown County
No CDC figure names Brown County; the nearest county with one, Bell County (103 miles away), reported 14.3% 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 Brown 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
MonitorAranet
Radon Plus battery digital radon monitor with an e-ink screen
- C-NRPP 2024/25: Approved
- Battery
- Bluetooth
- Alarm
- Screen, app
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
Brown County, Bordering counties
Counties bordering Brown County
Calculated by Radon411- Radon levels in Eastland CountyEPA zone 3
0.0%at or above 4 pCi/L
Median 0.1 pCi/L · 3 tests
- Radon levels in Comanche CountyEPA zone 3
No CDC figure for 2007 to 2016; its page reads it against its own neighbours.
- Radon levels in Coleman CountyEPA zone 3
No CDC figure for 2007 to 2016; its page reads it against its own neighbours.
- Radon levels in Mills CountyEPA zone 3
No CDC figure for 2007 to 2016; its page reads it against its own neighbours.
- Radon levels in Callahan CountyEPA zone 3
No CDC figure for 2007 to 2016; its page reads it against its own neighbours.
- Radon levels in San Saba CountyEPA zone 3
No CDC figure for 2007 to 2016; its page reads it against its own neighbours.
- Radon levels in McCulloch CountyEPA zone 3
No CDC figure for 2007 to 2016; its page reads it against its own neighbours.
Brown County, Cities and towns
Cities and towns in Brown County
The Census Bureau estimates 38,711 residents in Brown County for July 1, 2025, 655 more than in 2020 (+1.7%). That works out to 41 people per square mile of land. Its largest town, Brownwood, has 18,635 residents, 48.1% of the total. Together its 4 incorporated places hold 61.1% of those residents; the other 38.9% live outside any of them. Reported testing is thin here: 2 tests over 2008 to 2017, or 0.1 for every 1,000 residents (2025 estimate), where Texas as a whole comes to 0.1.
From Brownwood to Blanket, CDC publishes no figure by town: each reads Brown County's.
| Place | Residents | Since 2020 | Share of residents |
|---|---|---|---|
| Brownwood | 18,635 | −0.9% | 48.1% |
| Early | 3,117 | +1.2% | 8.1% |
| Bangs | 1,523 | −1.0% | 3.9% |
| Blanket | 362 | −0.8% | 0.9% |
4 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).
Brown County, Homes
Homes in Brown County
Of Brown County's 19,087 homes, 67% are detached houses, against 65% across Texas; 17% are mobile homes. The homes are older than Texas' as a whole: half were built before 1977 (1990 for Texas), and 26% date from before 1960. 68% 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 | Brown County | Texas |
|---|---|---|
| Housing units | 19,087 | 11,890,808 |
| Detached houses | 67% | 65% |
| In buildings of 5 or more | 10% | 21% |
| Mobile homes | 17% | 7% |
| Built before 1960 | 26% | 13% |
| Built since 2000 | 16% | 37% |
| Middle year built | 1977 | 1990 |
| Owner-occupied | 68% | 63% |
Census Bureau, American Community Survey, 2019 to 2023: estimates from a sample of homes, looser for a small place. Shares by Radon411.