
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
EPA puts La Salle 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, 84 miles
Share at 4+ pCi/L, 197 tests, 2007 to 2016
Ground above low
None
27.3 pts below Texas
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 highest, 3 lowest
EPA predicts under 2 pCi/L indoors
Read a result for La Salle County
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
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
La Salle County, At a glance
Predicted: EPA radon zone
USGS geologic potential: Low across 100% of the county's area
Predicted: EPA Map of Radon Zones
Measured: tests reported to CDC
CDC has published no radon test figures for La Salle County. Bexar County, 84 miles away, is the nearest county with a figure over the 2007 to 2016 laboratory totals.
La Salle County, Compared
CDC's county radon counts over the 2007 to 2016 laboratory totals cover 140 Texas counties, and La Salle County is not among them: no year's figure and no ten-year laboratory total names it. 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 (84 miles away) at 6.6%, Nueces County (100 miles away) at 0.0% and Travis County (158 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 La Salle 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.
La Salle County, Geology
USGS's geologic map puts all of La Salle 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.
Across Texas 0.5% of the land is rated high; none of La Salle 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
La Salle County, Local resources
The Texas Radon Group offers free radon test kits for Texas individuals who qualify.
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
La Salle County, Questions
No CDC testing statistics are published here for La Salle County, Texas yet. Of the 8 nearest counties with a figure, within 232 miles, the share of tests at or above 4 pCi/L runs from 0.0% to 14.3%.
La Salle County borders 6 counties: Frio County, McMullen County, Dimmit County, Atascosa County, Webb County and Duval County.
Products
La Salle County, Products
No CDC figure names La Salle County; the nearest county with one, Bexar County (84 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 La Salle County.
Test kits and monitors: 1 of 3
Explore
La Salle County, Bordering counties
0.0%at or above 4 pCi/L
Median 1.1 pCi/L · 1 test
0.0%at or above 4 pCi/L
Median 0.6 pCi/L · 6 tests
No CDC figure for 2007 to 2016; its page reads it against its own neighbours.
No CDC figure for 2007 to 2016; its page reads it against its own neighbours.
No CDC figure for 2007 to 2016; its page reads it against its own neighbours.
No CDC figure for 2007 to 2016; its page reads it against its own neighbours.
La Salle County, Cities and towns
About 6,517 people live in La Salle County by the Census Bureau's estimate for July 1, 2025, 125 fewer than in 2020 (−1.9%). Spread over its land, that is 4.4 people to the square mile. Cotulla alone is home to 3,583 of them, 55.0% of the total. Together its 2 incorporated places hold 63.3% of those residents; the other 36.7% live outside any of them. CDC publishes no radon test count for La Salle County; across Texas its counts for 2007 to 2016 come to 0.1 tests for every 1,000 residents (2025 estimate).
From Cotulla to Encinal, CDC publishes no figure by town: each reads La Salle County's.
| Place | Residents | Since 2020 | Share of residents |
|---|---|---|---|
| Cotulla | 3,583 | −3.6% | 55.0% |
| Encinal | 543 | +1.1% | 8.3% |
2 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).
La Salle County, Homes
Of La Salle County's 2,307 homes, 67% are detached houses, against 65% across Texas; 22% are mobile homes. The homes are older than Texas' as a whole: half were built before 1981 (1990 for Texas), and 34% date from before 1960. Owners live in 79% of the occupied homes (Texas: 63%), so for most households a test and a fix are their own to order.
| Homes | La Salle County | Texas |
|---|---|---|
| Housing units | 2,307 | 11,890,808 |
| Detached houses | 67% | 65% |
| In buildings of 5 or more | 8% | 21% |
| Mobile homes | 22% | 7% |
| Built before 1960 | 34% | 13% |
| Built since 2000 | 27% | 37% |
| Middle year built | 1981 | 1990 |
| Owner-occupied | 79% | 63% |
Census Bureau, American Community Survey, 2019 to 2023: estimates from a sample of homes, looser for a small place. Shares by Radon411.