Skip to content
RADON411

Locations and reports

Radon Levels in Randolph County, North Carolina

EPA puts Randolph County in Zone 3, its lowest radon zone, and only 3 radon tests from it are on file with CDC (2022). Homes with elevated levels occur in all three zones, so only a test measures yours.

Data checked By Radon411Methodology

How to test this homeFind a certified tester

  • Share at 4+ pCi/L

    7.1%

    15.5 pts below NC

    Randolph
    7.1%
    NC
    22.6%

    422 tests, 2008 to 2017

  • Median result

    0.9pCi/L

    Below action level

    Randolph
    0.9 pCi/L
    EPA
    4.0 pCi/L

    Midpoint of the tests, 2008 to 2017

  • Tests reported

    422

    38th of 75 by tests

    Randolph
    422
    Wake
    9,694

    Reported to CDC before any fix, 2008 to 2017

  • 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

  • Rank in NC

    59 of 75

    Lowest quarter

    Randolph
    7.1%
    Transylvania
    47.8%

    By share, of 75 with 30+ tests

Read a result for Randolph County

Starts at Randolph County's median, 0.9 pCi/L

0.9pCi/L

EPA’s own thresholds; the figures are the area’s, never this home’s.

EPA’s reading of 0.9 pCi/L

Below 2 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 below 2 pCi/L, the level at which EPA says a fix should be considered. Randolph County's median reported result, 2008 to 2017.

Interpret this reading

The data

Randolph County, At a glance

Randolph County at a glance

Predicted: EPA radon zone

EPA Zone 3: lower predicted potential

is EPA's lowest class, and its forecast for Randolph 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 Randolph County, 2022

Share of reported tests at or above 4 pCi/L, by year, Randolph County
Share of reported tests at or above 4 pCi/L, by year, Randolph County
YearShare of reported tests at or above 4 pCi/L
20143.8%
20206.3%
20210.0%
20220.0%

2022: 0.0%. Across these years the share ran from 0.0% to 6.3%. Each column counts radon tests reported to CDC that year, not homes.

What these figures count

Only 3 tests were reported to CDC for Randolph County over 2022, 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: 2022. Measured data period: 2005 to 2022 (every CDC figure on file).

How to read these figures

Randolph County, Compared

Randolph County radon figures, compared

Calculated by Radon411

Randolph County reports fewer high tests than North Carolina overall. 7.1% of its 422 tests over the 2008 to 2017 laboratory totals were at or above 4 pCi/L. That is 15.5 points below the 22.6% pooled from 99 North Carolina counties.

The newest figure, in 2022, counts only 3 tests (0.0% at or above 4 pCi/L), too few to compare, so this reading uses the 422-test figure.

Ordered from highest share down, it comes 59th of 75 North Carolina counties with 30 or more tests for the same period. Nationally, every county with a figure for the same period pools to 35.7%; Randolph County sits 28.6 points below it.

Next door, the shares run from 3.7% in Alamance County to 25.5% in Davidson County, with Alamance County below Randolph County. Zone 3 on EPA's map (predicted average under 2 pCi/L) and a 7.1% share point the same way here.

Half the tests came in under 0.9 pCi/L and half over it; the single highest reached 18.9 pCi/L. The rest split 77.0% under 2 pCi/L and 15.9% from 2 to 4 (North Carolina: 55.6% and 21.8%).

The busiest year on file was 2020, with 32 tests reported; the quietest, 2022, had 3.

Randolph County against North Carolina, the United States and nearby counties, 2008 to 2017, laboratory
AreaTestsAt or above 4 pCi/LMedianDifference from Randolph County
Randolph County4227.1%0.9 pCi/LThis county
North Carolina, pooled99 counties, pooled73,13922.6%Not pooled+15.5 points
United States, pooled2,661 counties, pooled2,013,54435.7%Not pooled+28.6 points
Transylvania Countyhighest in the state3,86247.8%3.7 pCi/L+40.7 points
Nash Countylowest in the state300.0%0.2 pCi/L−7.1 points
Davidson County, NCborders it1,26525.5%1.8 pCi/L+18.4 points
Montgomery County, NCborders it10320.4%1.5 pCi/L+13.3 points
Moore County, NCborders it9919.2%1.3 pCi/L+12.1 points
Chatham County, NCborders it58710.9%1.1 pCi/L+3.8 points
Guilford County, NCborders it6,8707.9%0.9 pCi/L+0.8 points
Alamance County, NCborders it5203.7%0.5 pCi/L−3.4 points
Where Randolph County's reported results fell, 2008 to 2017, laboratory, beside North Carolina and the United States
ResultRandolph County testsRandolph County shareNorth Carolina shareU.S. shareAgainst North Carolina
Under 2 pCi/L32577.0%55.6%39.6%+21.4 points
2 to 4 pCi/L6715.9%21.8%24.7%−5.9 points
4 pCi/L and above307.1%22.6%35.7%−15.5 points
Randolph County ranked among the 75 North Carolina counties with 30 or more tests, by share at or above 4 pCi/L, 2008 to 2017, laboratory
CountyRankTestsAt or above 4 pCi/LMedian
Cabarrus County54 of 758808.8%1.0 pCi/L
Mecklenburg County55 of 753,7538.5%0.9 pCi/L
Johnston County56 of 756688.2%0.7 pCi/L
Wayne County57 of 75498.2%0.6 pCi/L
Guilford County58 of 756,8707.9%0.9 pCi/L
Randolph County59 of 754227.1%0.9 pCi/L
Durham County60 of 751,5704.3%0.7 pCi/L
Robeson County61 of 75533.8%0.8 pCi/L
Alamance County62 of 755203.7%0.5 pCi/L
New Hanover County63 of 751173.4%0.1 pCi/L
Scotland County64 of 75313.2%1.0 pCi/L
Randolph County radon tests by year, against North Carolina's pooled share
YearTestsAt or above 4 pCi/LMedianHighestNorth Carolina, pooledChange from the row before
202230.0%1.0 pCi/L1.0 pCi/L10.7%Level
202180.0%0.1 pCi/L1.0 pCi/L14.9%−6.3 points
2020326.3%0.9 pCi/L4.5 pCi/L21.1%+2.5 points
2014263.8%0.4 pCi/L4.9 pCi/L21.9%First on file

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

Randolph County, Geology

The ground under Randolph County

Predicted

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

USGS's geologic areas under Randolph County
AreaThe rock, in USGS's wordsPotentialRadon indexShare of land
Carolina Slate BeltFelsic metavolcanics, intermediate volcanics, metamudstone, argillite, and epiclastic rocks.Low6100%

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

Randolph County beside the ground around it

Across North Carolina 1.3% of the land is rated high; none of Randolph County's is. Of the 6 counties that border it, 2 have more moderate-potential ground, Guilford County the most at 9.1%.

Share of land by USGS radon potential: Randolph County, the 6 counties bordering it and North Carolina
AreaEPA zoneLow potentialModerate potentialHigh potential
Randolph CountyZone 3100%NoneNone
Montgomery CountyZone 3100%NoneNone
Davidson CountyZone 3100%NoneNone
Guilford CountyZone 390.9%9.1%None
Chatham CountyZone 398.6%1.4%None
Moore CountyZone 3100%NoneNone
Alamance CountyZone 3100%NoneNone
North Carolina100 counties, pooled by land areaVaries64.8%33.0%1.3%

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

Local help

Randolph County, Local resources

Radon testing and mitigation in Randolph County

What North Carolina's program says
Licensing of radon professionals
The North Carolina Radon Program is presently developing a Radon Proficiency Program as directed by Session Law 2023-91 House Bill 782 .

What it means

Randolph County, Questions

Questions about radon in Randolph County

Are radon levels high in Randolph County?

In 2022, 0.0% of the radon tests reported to CDC for Randolph County, North Carolina were at or above 4 pCi/L, and the median reported pre-mitigation result was 1.0 pCi/L. Of 75 North Carolina counties with 30 or more tests for the same period, 58 reported a higher share; pooled, the state comes to 22.6%.

Which counties border Randolph County?

Randolph County borders 6 counties: Montgomery County, Davidson County, Guilford County, Chatham County, Moore County and Alamance County.

Products

Randolph County, Products

Testing a home in Randolph County

In Randolph County, 7.1% of 422 tests reported to CDC over the 2008 to 2017 laboratory totals reached 4 pCi/L, against 22.6% pooled across North Carolina. 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 Randolph County.

Test kits and monitors3

See every kit and monitor

Best radon monitors for Randolph County homes, compared

Explore

Randolph County, Bordering counties

Counties bordering Randolph County

Calculated by Radon411

Randolph County, Cities and towns

Cities and towns in Randolph County

The Census Bureau estimates 149,516 residents in Randolph County for July 1, 2025, 5,115 more than in 2020 (+3.5%). That works out to 191 people per square mile of land. High Point, the largest place on its list (120,571 residents in all), extends beyond Randolph County, so no share of the total is worked out for it. Reported testing is thin here: 422 tests over 2008 to 2017, or 2.8 for every 1,000 residents (2025 estimate), where North Carolina as a whole comes to 6.5.

From High Point to Seagrove, CDC publishes no figure by town: each reads Randolph County's.

The cities and towns in Randolph County by residents, July 1, 2025
PlaceResidentsSince 2020Share of residents
High Pointextends beyond Randolph County120,571+5.1%Counted whole
Asheboro27,990+2.7%18.7%
Thomasvilleextends beyond Randolph County27,733+2.4%Counted whole
Archdaleextends beyond Randolph County12,254+2.9%Counted whole
Trinity7,274+3.2%4.9%
Randleman4,767+2.8%3.2%
Liberty2,739+3.0%1.8%
Ramseur1,806+1.8%1.2%
Franklinville1,256+4.3%0.8%
Staley405+4.1%0.3%
Seagrove248+5.5%0.2%

11 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 Randolph County is counted whole, so it has no share.

Randolph County, Homes

Homes in Randolph County

Of Randolph County's 62,544 homes, 67% are detached houses, against 65% across North Carolina; 20% are mobile homes. Half of its homes were built before 1985, close to North Carolina's 1990: 19% date from before 1960 and 23% from 2000 or later. 73% of occupied homes are lived in by their owner (North Carolina: 66%); in the rest a tenant can run a test, but a fix is the landlord's to make.

Homes in Randolph County, North Carolina, 2019 to 2023
HomesRandolph CountyNorth Carolina
Housing units62,5444,815,195
Detached houses67%65%
In buildings of 5 or more6%14%
Mobile homes20%11%
Built before 196019%14%
Built since 200023%33%
Middle year built19851990
Owner-occupied73%66%

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