Short-term kit
Air Chek Short-Term radon test kit you hang, lab fee included
- Lab fee included
In home: 72 to 168 hours
Locations and reports
Radon Levels in Dallam County, Texas
EPA puts Dallam County in Zone 2, its middle radon zone, and only 1 radon test from it is 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
20.0%
Potter County, 72 miles
- Potter
- 20.0%
- Texas
- 10.4%
Share at 4+ pCi/L, 70 tests, 2007 to 2016
Ground above low
100.0%
72.7 pts above Texas
- Dallam
- 100.0%
- Texas
- 27.3%
Share of land USGS rates moderate or high potential
Tests reported
1
Too few for a share
- Dallam
- 1
- Needed
- 30
2008 to 2017, 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 Dallam 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
Dallam County, At a glance
Dallam County at a glance
Predicted: EPA radon zone
EPA Zone 2: moderate predicted potential
Dallam County is a
USGS geologic potential: Moderate across 100% of the county's area
Predicted: EPA Map of Radon Zones
Measured: tests reported to CDC
Radon tests reported for Dallam County, 2008 to 2017, laboratory
CDC holds 1 reported test for Dallam County over the 2008 to 2017 laboratory totals, a result of 4.2 pCi/L: too few to describe a county (Radon411 reads a share from 30 tests up). Dallam County beside the counties around it is how this page reads it.
What these figures count
Only 1 test was reported to CDC for Dallam 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).
Dallam County, Compared
Dallam County radon figures, compared
Calculated by Radon411CDC's largest figure for Dallam County rests on 1 test over the 2008 to 2017 laboratory totals, 1 of them at or above 4 pCi/L, so each test moves its share by 100.0 points and no rank or comparison is drawn from it. Results reached as high as 4.2 pCi/L, with a middle value of 4.2 pCi/L.
The nearest counties with a figure are Potter County (72 miles away) at 20.0%, Randall County (99 miles away) at 71.4% and Lubbock County (189 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 Dallam County in Zone 2, its middle label: a predicted county average between 2 and 4 pCi/L. USGS geology rates 100% of the county's land moderate radon potential.
Pooled shares: Radon411's sum of CDC's county counts for one period.
Dallam County, Geology
The ground under Dallam County
PredictedUSGS's geologic map puts all of Dallam County's mapped land in one class: moderate radon potential. All of it lies in the area the map calls Northern High Plains and Plateaus, to which USGS gives a radon index of 10, in the moderate band (9 to 11).
| Area | The rock, in USGS's words | Potential | Radon index | Share of land |
|---|---|---|---|---|
| Northern High Plains and Plateaus | Tertiary sandstone, siltstone, shale. | Moderate | 10 | 99.8% |
Names, descriptions and indexes: U.S. Geological Survey, Geologic Radon Potential Map (2025). Shares: Radon411, from the map cut to the boundary.
Dallam County beside the ground around it
Across Texas 0.5% of the land is rated high; none of Dallam County's is. Of the 5 counties that border it, 2 have more high-potential ground, Union County, NM the most at 33.0%.
The map rates the ground, not the air in any home.
Local help
Dallam County, Local resources
Radon testing and mitigation in Dallam 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
Dallam County, Questions
Questions about radon in Dallam County
Are radon levels high in Dallam County?
Over the 2008 to 2017 laboratory totals, 100.0% of the radon tests reported to CDC for Dallam County, Texas were at or above 4 pCi/L, and the median reported pre-mitigation result was 4.2 pCi/L. Of the 8 nearest counties with a figure, within 404 miles, the share of tests at or above 4 pCi/L runs from 0.0% to 71.4%.
Which counties border Dallam County?
Dallam County borders 5 counties: Hartley County, TX, Cimarron County, OK, Sherman County, TX, Moore County, TX and Union County, NM.
Products
Dallam County, Products
Testing a home in Dallam County
No CDC figure names Dallam County; the nearest county with one, Potter County (72 miles away), reported 20.0% 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 Dallam County; a long-term test tells the year-round average.
Test kits and monitors3
See every kit and monitor
Long-term kit
RL116 long-term radon test kit
- Lab fee extra
Method: Alpha track
In home: 90 days to 12 months
MonitorX-Sense
XR0A-iR Wi-Fi battery radon detector with a screen
- C-NRPP 2024/25: Not included
- Battery
- Wi-Fi
- Screen, app
Method: Alpha spectrometry
First reading: Within 24 hours
- See every kit and monitor Test kits and monitors
Test kits and monitors: 1 of 3
Explore
Dallam County, Bordering counties
Counties bordering Dallam County
Calculated by Radon411- Radon levels in Moore County, TXEPA zone 2
100.0%at or above 4 pCi/L
Median 4.7 pCi/L · 2 tests
- Radon levels in Union County, NMEPA zone 2
100.0%at or above 4 pCi/L
Median 4.1 pCi/L · 1 test
- Radon levels in Cimarron County, OKEPA zone 2
66.7%at or above 4 pCi/L
Median 4.7 pCi/L · 3 tests
- Radon levels in Hartley County, TXEPA zone 2
50.0%at or above 4 pCi/L
Median 6.1 pCi/L · 2 tests
- Radon levels in Sherman County, TXEPA zone 2
0.0%at or above 4 pCi/L
Median 1.3 pCi/L · 1 test
Dallam County, Cities and towns
Cities and towns in Dallam County
Dallam County is growing: the Census Bureau puts it at 7,508 residents on July 1, 2025, up 5.2% from 7,137 in 2020. Spread over its land, that is 5.0 people to the square mile. Dalhart, the largest place on its list (8,377 residents in all), extends beyond Dallam County, so no share of the total is worked out for it. CDC's 1 reported test for 2008 to 2017 work out to 0.1 per 1,000 residents (2025 estimate), close to Texas' 0.1.
From Dalhart to Texline, CDC publishes no figure by town: each reads Dallam County's.
| Place | Residents | Since 2020 | Share of residents |
|---|---|---|---|
| Dalhartextends beyond Dallam County | 8,377 | −0.4% | Counted whole |
| Texline | 492 | +8.4% | 6.6% |
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). A place that extends beyond Dallam County is counted whole, so it has no share.
Dallam County, Homes
Homes in Dallam County
Dallam County is a place of houses on their own lots: 76% of its 3,053 homes are detached single-family houses, against 65% across Texas. The homes are older than Texas' as a whole: half were built before 1976 (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 | Dallam County | Texas |
|---|---|---|
| Housing units | 3,053 | 11,890,808 |
| Detached houses | 76% | 65% |
| In buildings of 5 or more | 9% | 21% |
| Mobile homes | 11% | 7% |
| Built before 1960 | 26% | 13% |
| Built since 2000 | 16% | 37% |
| Middle year built | 1976 | 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.