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Radon in Greensboro, North Carolina

EPA puts Guilford County, where Greensboro is, in Zone 3, its lowest radon zone, and only 13 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

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  • Share at 4+ pCi/L

    7.9%

    14.7 pts below NC

    Guilford
    7.9%
    NC
    22.6%

    Guilford, 58th of 75 in NC, 2008 to 2017

  • Median result

    0.9pCi/L

    Below action level

    Guilford
    0.9 pCi/L
    EPA
    4.0 pCi/L

    Midpoint of Guilford's tests, 2008 to 2017

  • Nearest county

    27.3%

    Rockingham, 21 miles

    Rockingham
    27.3%
    Guilford
    7.9%

    835 tests, 2008 to 2017

  • EPA radon zone

    Zone 3

    Low potential

    1. 1
    2. 2
    3. Zone 3

    1 highest, 3 lowest

    Guilford, where Greensboro is

  • Tests reported

    6,870

    In Guilford

    Guilford
    6,870
    Rockingham
    835

    Reported to CDC before any fix, 2008 to 2017

Read a result for Greensboro

Starts at Guilford 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. Guilford County's median reported result, 2008 to 2017.

Interpret this reading

The data

Greensboro, What is published

What is published for Greensboro

Information:

Every figure for Greensboro is a county's

Radon data is published by county, not by city, so for Greensboro it is Guilford County's: its EPA zone (Zone 3) and the 13 tests reported to CDC for 2022. Only a test tells you about one home.

Greensboro covers 130 square miles of land, all of it in Guilford County. About 308,667 people live there, 2,382 to the square mile.

Greensboro, Counties

The county Greensboro lies in

Measured

Guilford County's EPA zone and the figures CDC publishes for it, 2022.

Guilford CountyZone 3Lower predicted potential

15.4%
Reported tests at or above 4 pCi/L
1.0 pCi/L
Median reported result
13 tests
Tests reported to CDC
4
Annual years on file

Guilford County ranks 58th of 75 North Carolina counties with 30 or more tests for that period, 7.2 points below the 22.6% pooled across North Carolina's counties, 20.3 points below the national pool of 35.7%.

The counties nearest Greensboro with a CDC figure for 2008 to 2017, laboratory, measured from the middle of the city: Rockingham County (21 miles, 27.3% of 835 tests), Forsyth County (24 miles, 28.9% of 6,273 tests) and Alamance County (24 miles, 3.7% of 520 tests). Across the 8 nearest, the share at or above 4 pCi/L runs from 3.7% to 28.9%; the farthest of them, Orange County, is 40 miles away at 10.7%.

No business in the directory gives Greensboro as its address; the North Carolina list covers it. North Carolina's other cities with a page of their own: Raleigh, Asheville, Charlotte and Boone.

The counties around Greensboro

By distance from the middle of Greensboro; counties with 30 or more tests.

Nearest counties to Greensboro with 30 or more tests
CountyDistanceTestsAt or above 4 pCi/LMedian
Rockingham County21 mi83527.3%2.1 pCi/L
Forsyth County24 mi6,27328.9%2.3 pCi/L
Alamance County24 mi5203.7%0.5 pCi/L
Randolph County27 mi4227.1%0.9 pCi/L
Davidson County30 mi1,26525.5%1.8 pCi/L
Stokes County31 mi59221.6%1.8 pCi/L
Caswell County34 mi4714.9%1.6 pCi/L
Orange County40 mi1,09510.7%1.1 pCi/L

Predicted: EPA Map of Radon Zones, by county. Measured: CDC tracking data, by county, 2022.

Greensboro, Geology

The ground under Greensboro

Predicted

USGS's geologic map puts all of Greensboro's mapped land in one class: low radon potential. The map puts 56.3% of Greensboro in the area it calls Carolina Slate Belt and 43.7% in Charlotte Belt. USGS gives the first a radon index of 6 and the second 8, both in the low band (5 to 8).

USGS's geologic areas under Greensboro
AreaThe rock, in USGS's wordsPotentialRadon indexShare of land
Carolina Slate BeltFelsic metavolcanics, intermediate volcanics, metamudstone, argillite, and epiclastic rocks.Low656.3%
Charlotte BeltIgneous rocks, including granite, gabbro, and diorite.Low843.7%

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

Greensboro beside its county and North Carolina

Guilford County as a whole has 9.1% of its land rated moderate; none of that ground lies under Greensboro. Across North Carolina 1.3% of the land is rated high; none of Greensboro's is.

Share of land by USGS radon potential: Greensboro, the county it lies in and North Carolina
AreaEPA zoneLow potentialModerate potentialHigh potential
GreensboroBy county100%NoneNone
Guilford CountyZone 390.9%9.1%None
North Carolina100 counties, pooled by land areaVaries64.8%33.0%1.3%

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

Greensboro, Homes

Homes in Greensboro

Greensboro has 133,565 homes, and many share a building: 31% are in buildings of five or more, 53% are detached houses, against 63% across Guilford County. Half of its homes were built before 1983, close to Guilford County's 1986: 20% date from before 1960 and 25% from 2000 or later. 50% of occupied homes are lived in by their owner (Guilford County: 60%); in the rest a tenant can run a test, but a fix is the landlord's to make.

Homes in Greensboro, Guilford County, North Carolina, 2019 to 2023
HomesGreensboroGuilford CountyNorth Carolina
Housing units133,565235,8334,815,195
Detached houses53%63%65%
In buildings of 5 or more31%22%14%
Mobile homes1%3%11%
Built before 196020%18%14%
Built since 200025%28%33%
Middle year built198319861990
Owner-occupied50%60%66%

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

Local help

Greensboro, Local resources

Local resources for Greensboro

Who to ask in North Carolina: its radon program, test kits and professionals.

The program's own words on licensing are on the North Carolina page.

What it means

Greensboro, Questions

Questions about radon in Greensboro

What radon zone is Greensboro in?

EPA's map puts Guilford County, and with it Greensboro, in Zone 3, the map's lowest class: a predicted county average under 2 pCi/L. A low zone does not clear a house: homes over the action level are found in all three.

What are radon levels in Greensboro?

Only 13 tests from Guilford County are on file with CDC for 2022, 15.4% of them at or above 4 pCi/L: too few to say how Greensboro runs.

Should I test my home in Greensboro?

Yes. With no dependable count of tests for Guilford County, a test of your own is the only reading there is; a short-term kit takes a few days. How to test a home.

What ground is Greensboro built on, as far as radon goes?

56.3% of Greensboro sits on what USGS's map calls "Carolina Slate Belt", rated low for radon potential, radon index 6; another 43.7% is "Charlotte Belt", in the same class.

Is radon higher in the counties around Greensboro?

Some are and some are not. Against Guilford County's 15.4%, 4 of the 8 nearest counties with a figure report more and 4 less, from Alamance County (3.7%, 24 miles off) to Forsyth County (28.9%, 24 miles off).

The answers use the published figures of Guilford County, the county Greensboro lies in.

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