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Radon Levels in Navarro County, Texas

EPA puts Navarro County in Zone 3, its lowest radon zone, and only 6 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

    8.7%

    Dallas County, 53 miles

    Dallas
    8.7%
    Texas
    10.4%

    Share at 4+ pCi/L, 699 tests, 2007 to 2016

  • Ground above low

    None

    27.3 pts below Texas

    Navarro
    0.0%
    Texas
    27.3%

    Share of land USGS rates moderate or high potential

  • Tests reported

    6

    Too few for a share

    Navarro
    6
    Needed
    30

    2008 to 2017, laboratory

  • EPA radon zone

    Zone 3

    Lower potential

    1. 1
    2. 2
    3. Zone 3

    1 highest, 3 lowest

    EPA predicts under 2 pCi/L indoors

Read a result for Navarro County

Starts at EPA's action level

4.0pCi/L

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

  1. Under 20 to 1.9 pCi/L
  2. 2 to 4consider a fix
  3. 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

Navarro County, At a glance

Navarro County at a glance

Predicted: EPA radon zone

EPA Zone 3: lower predicted potential

is EPA's lowest class, and its forecast for Navarro County as a whole is an average indoor of less than 2 pCi/L (less than 75 Bq/m³). A low zone clears no address in it: homes above EPA's turn up in all three zones.

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 Navarro County, 2008 to 2017, laboratory

CDC holds 6 reported tests for Navarro County over the 2008 to 2017 laboratory totals, with a median of 0.8 pCi/L: too few to describe a county (Radon411 reads a share from 30 tests up). Navarro County beside the counties around it is how this page reads it.

What these figures count

Only 6 tests were reported to CDC for Navarro 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).

How to read these figures

Navarro County, Compared

Navarro County radon figures, compared

Calculated by Radon411

CDC's largest figure for Navarro County rests on 6 tests over the 2008 to 2017 laboratory totals, 0 of them at or above 4 pCi/L, so each test moves its share by 16.7 points and no rank or comparison is drawn from it. Results reached as high as 1.1 pCi/L, with a middle value of 0.8 pCi/L.

The nearest counties with a figure are Dallas County (53 miles away) at 8.7%, McLennan County (55 miles away) at 17.1% and Tarrant County (69 miles away) at 10.6%. 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 Navarro 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.

Texas, the United States and the counties around Navarro County, 2007 to 2016, laboratory
AreaTestsAt or above 4 pCi/LMedian
Texas, pooled140 counties, pooled4,54810.4%Not pooled
United States, pooled2,666 counties, pooled1,939,02535.8%Not pooled
Randall Countyhighest in the state8471.4%6.2 pCi/L
Nueces Countylowest in the state450.0%0.6 pCi/L
Ellis County, TXborders it1457.1%11.0 pCi/L
Limestone County, TXborders it20.0%0.1 pCi/L
Hill County, TXborders it50.0%0.1 pCi/L
Henderson County, TXborders it10.0%0.8 pCi/L
Freestone County, TXborders it100.0%0.9 pCi/L
The nearest Texas counties to Navarro County with 30 or more tests, 2007 to 2016, laboratory
CountyDistanceTestsAt or above 4 pCi/LMedian
Dallas County53 mi6998.7%1.0 pCi/L
McLennan County55 mi4117.1%1.0 pCi/L
Tarrant County69 mi31210.6%0.9 pCi/L
Smith County74 mi339.1%0.8 pCi/L
Collin County79 mi2847.7%1.0 pCi/L
Denton County88 mi1817.2%0.9 pCi/L
Bell County91 mi3514.3%1.1 pCi/L
Brazos County96 mi490.0%0.2 pCi/L
Navarro County ten-year laboratory totals, against Texas' pooled share
PeriodTestsAt or above 4 pCi/LMedianHighestTexas, pooledChange from the row before
2008 to 201760.0%0.8 pCi/L1.1 pCi/L10.2%Level
2007 to 201660.0%0.8 pCi/L1.1 pCi/L10.4%Level
2006 to 201560.0%0.8 pCi/L1.1 pCi/L11.0%Level
2005 to 201450.0%0.8 pCi/L1.1 pCi/L10.6%First on file

Pooled shares: Radon411's sum of CDC's county counts for one period.

Navarro County, Geology

The ground under Navarro County

Predicted

USGS's geologic map puts all of Navarro County's mapped land in one class: low radon potential. All of it lies in the area the map calls East Texas Province, to which USGS gives a radon index of 6, in the low band (5 to 8).

USGS's geologic areas under Navarro County
AreaThe rock, in USGS's wordsPotentialRadon indexShare of land
East Texas ProvinceCretaceous through Quaternary marine sandstone, shale, chalk, limestone, siltstone, clay, and lignite.Low6100%

Names, descriptions and indexes: U.S. Geological Survey, Geologic Radon Potential Map (2025). Shares: Radon411, from the map cut to the boundary.

Navarro County beside the ground around it

Across Texas 0.5% of the land is rated high; none of Navarro County's is. Of the 5 counties that border it, 2 have more moderate-potential ground, Hill County the most at 54.9%.

Share of land by USGS radon potential: Navarro County, the 5 counties bordering it and Texas
AreaEPA zoneLow potentialModerate potentialHigh potential
Navarro CountyZone 3100%NoneNone
Ellis CountyZone 358.7%41.3%None
Freestone CountyZone 3100%NoneNone
Hill CountyZone 345.1%54.9%None
Henderson CountyZone 3100%NoneNone
Limestone CountyZone 3100%NoneNone
Texas254 counties, pooled by land areaVaries72.4%26.8%0.5%

The map rates the ground, not the air in any home.

Local help

Navarro County, Local resources

Radon testing and mitigation in Navarro County

What it means

Navarro County, Questions

Questions about radon in Navarro County

Are radon levels high in Navarro County?

Over the 2008 to 2017 laboratory totals, 0.0% of the radon tests reported to CDC for Navarro County, Texas were at or above 4 pCi/L, and the median reported pre-mitigation result was 0.8 pCi/L. Of the 8 nearest counties with a figure, within 96 miles, the share of tests at or above 4 pCi/L runs from 0.0% to 17.1%.

Which counties border Navarro County?

Navarro County borders 5 counties: Ellis County, Freestone County, Hill County, Henderson County and Limestone County.

Products

Navarro County, Products

Testing a home in Navarro County

No CDC figure names Navarro County; the nearest county with one, Dallas County (53 miles away), reported 8.7% 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 Navarro County.

Explore

Navarro County, Bordering counties

Counties bordering Navarro County

Calculated by Radon411

Navarro County, Cities and towns

Cities and towns in Navarro County

Navarro County is growing: the Census Bureau puts it at 57,181 residents on July 1, 2025, up 8.2% from 52,843 in 2020. That works out to 57 people per square mile of land. Its largest town, Corsicana, has 25,487 residents, 44.6% of the total. CDC's 6 reported tests for 2008 to 2017 work out to 0.1 per 1,000 residents (2025 estimate), close to Texas' 0.1.

From Corsicana to Mustang, CDC publishes no figure by town: each reads Navarro County's.

The 12 largest cities and towns in Navarro County by residents, July 1, 2025
PlaceResidentsSince 2020Share of residents
Corsicana25,487+1.4%44.6%
Kerens1,508−0.3%2.6%
Rice1,286+7.5%2.2%
Blooming Grove882+2.3%1.5%
Dawson822Level1.4%
Frost628+1.1%1.1%
Mildred473+17.7%0.8%
Angus448+4.2%0.8%
Retreat443+8.0%0.8%
Oak Valley409+1.2%0.7%
Eureka374+18.7%0.7%
Streetmanextends beyond Navarro County275+10.9%Counted whole
  • Richland
  • Barry
  • Navarro
  • Emhouse
  • Goodlow
  • Powell
  • Mustang

19 incorporated places, as listed in the U.S. Census Bureau’s 2020 place reference files. “(part)” marks a place that extends into another county. Residents: U.S. Census Bureau population estimates for July 1, 2025 (Vintage 2025). A place that extends beyond Navarro County is counted whole, so it has no share.

Navarro County, Homes

Homes in Navarro County

Of Navarro County's 21,790 homes, 70% are detached houses, against 65% across Texas; 18% are mobile homes. The homes are older than Texas' as a whole: half were built before 1982 (1990 for Texas), and 20% 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 in Navarro County, Texas, 2019 to 2023
HomesNavarro CountyTexas
Housing units21,79011,890,808
Detached houses70%65%
In buildings of 5 or more6%21%
Mobile homes18%7%
Built before 196020%13%
Built since 200024%37%
Middle year built19821990
Owner-occupied68%63%

Census Bureau, American Community Survey, 2019 to 2023: estimates from a sample of homes, looser for a small place. Shares by Radon411.