Skip to content
RADON411

Locations and reports

Radon Levels in Rockingham County, Virginia

EPA puts Rockingham County in Zone 1, its highest radon zone, and high results are common there: 43.9% of the 1,714 radon tests reported to CDC (2008 to 2017, laboratory totals) came back at or above 4 pCi/L. 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

    43.9%

    13.5 pts above VA

    Rockingham
    43.9%
    Virginia
    30.4%

    1,714 tests, 2008 to 2017

  • Median result

    3.3pCi/L

    Below action level

    Rockingham
    3.3 pCi/L
    EPA
    4.0 pCi/L

    Midpoint of the tests, 2008 to 2017

  • Tests reported

    1,714

    8th of 84 by tests

    Rockingham
    1,714
    Fairfax
    8,657

    Reported to CDC before any fix, 2008 to 2017

  • EPA radon zone

    Zone 1

    Highest potential

    1. Zone 1
    2. 2
    3. 3

    1 highest, 3 lowest

    EPA predicts over 4 pCi/L indoors

  • Rank in Virginia

    21 of 84

    Top quarter

    Rockingham
    43.9%
    Russell
    67.3%

    By share, of 84 with 30+ tests

Read a result for Rockingham County

Starts at Rockingham County's median, 3.3 pCi/L

3.3pCi/L

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

EPA’s reading of 3.3 pCi/L

Between 2 and 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 between 2 and 4 pCi/L. EPA recommends considering a fix when the level is between 2 and 4 pCi/L. Rockingham County's median reported result, 2008 to 2017.

Interpret this readingWhat a fix costs

The data

Rockingham County, At a glance

Rockingham County at a glance

Predicted: EPA radon zone

EPA Zone 1: highest predicted potential

EPA puts all of Rockingham County in and predicts an average indoor of greater than 4 pCi/L (greater than 150 Bq/m³) across the county. That is one forecast for the whole county, not a reading of any address in it; homes above EPA's turn up in all three zones.

USGS geologic potential: High across 95% of the county's area

Predicted: EPA Map of Radon Zones

Measured: tests reported to CDC

Radon tests reported for Rockingham County, 2008 to 2017, laboratory

Reported results by concentration band, Rockingham County, 2008 to 2017, laboratory
Under 2 pCi/L: 31%2 to 4 pCi/L: 25%4 pCi/L and above: 44%

Of 1,714 pre-mitigation tests reported to CDC, not homes in this area.

Reported results by concentration band, Rockingham County, 2008 to 2017, laboratory: data table
Result bandTests MeasuredShare Measured
Under 2 pCi/L53831.4%
2 to 4 pCi/L42324.7%
4 pCi/L and above75343.9%
What these figures count

These are the 1,714 tests reported to CDC for Rockingham County over 2008 to 2017 (laboratory totals), many from homes being sold or already suspected of a problem: they describe the county's reported tests, not 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

Rockingham County, Compared

Rockingham County radon figures, compared

Calculated by Radon411

In Rockingham County, about 4 in 10 reported tests over the 2008 to 2017 laboratory totals (753 of 1,714) were at or above EPA's action level. Against the national pool of 35.7%, the gap is 8.2 points higher. Across 131 Virginia counties pooled together, 30.4% of tests reached that level, so Rockingham County runs 13.5 points above its state.

Of 8 neighbours with a figure, 1 reported a larger share at or above 4 pCi/L and 7 a smaller one; the spread is 22.6% (Hardy County, WV) to 50.1% (Augusta County). By share, Rockingham County is 21st of 84 Virginia counties with 30 or more tests for the same period.

Half the tests came in under 3.3 pCi/L and half over it; the single highest reached 88.8 pCi/L. Below the action level, 538 tests (31.4%) came in under 2 pCi/L, against 44.7% statewide, and 423 tests (24.7%) fell between 2 and 4, against 24.9% statewide.

Zone 1 on EPA's map (predicted average above 4 pCi/L) and a 43.9% share point the same way here. USGS geology rates 95% of the county's land high radon potential. CDC also counts 117 tests taken after mitigation in Rockingham County for the same period: tests in homes where a fix was already in.

CDC's ten-year totals for Rockingham County went from 1,311 tests (2005 to 2014) to 1,714 (2008 to 2017), the share going from 43.8% to 43.9%.

Rockingham County against Virginia, the United States and nearby counties, 2008 to 2017, laboratory
AreaTestsAt or above 4 pCi/LMedianDifference from Rockingham County
Rockingham County1,71443.9%3.3 pCi/LThis county
Virginia, pooled131 counties, pooled53,19930.4%Not pooled−13.5 points
United States, pooled2,661 counties, pooled2,013,54435.7%Not pooled−8.2 points
Russell Countyhighest in the state4967.3%6.7 pCi/L+23.4 points
Norfolk citylowest in the state732.7%0.5 pCi/L−41.2 points
Augusta County, VAborders it62550.1%4.0 pCi/L+6.2 points
Page County, VAborders it14138.3%3.3 pCi/L−5.6 points
Shenandoah County, VAborders it39036.4%2.7 pCi/L−7.5 points
Greene County, VAborders it21434.6%2.8 pCi/L−9.3 points
Harrisonburg city, VAborders it59933.4%2.4 pCi/L−10.5 points
Pendleton County, WVborders it5530.9%2.5 pCi/L−13.0 points
Albemarle County, VAborders it2,17924.7%2.1 pCi/L−19.2 points
Hardy County, WVborders it5322.6%1.6 pCi/L−21.3 points
Where Rockingham County's reported results fell, 2008 to 2017, laboratory, beside Virginia and the United States
ResultRockingham County testsRockingham County shareVirginia shareU.S. shareAgainst Virginia
Under 2 pCi/L53831.4%44.7%39.6%−13.3 points
2 to 4 pCi/L42324.7%24.9%24.7%−0.2 points
4 pCi/L and above75343.9%30.4%35.7%+13.5 points
Rockingham County ranked among the 84 Virginia counties with 30 or more tests, by share at or above 4 pCi/L, 2008 to 2017, laboratory
CountyRankTestsAt or above 4 pCi/LMedian
King George County16 of 8448845.5%3.6 pCi/L
Winchester city17 of 8477344.8%3.3 pCi/L
Grayson County18 of 844744.7%3.8 pCi/L
Frederick County19 of 842,45144.1%3.3 pCi/L
Madison County20 of 8418444.0%3.5 pCi/L
Rockingham County21 of 841,71443.9%3.3 pCi/L
Floyd County22 of 845442.6%3.3 pCi/L
Botetourt County23 of 8457542.1%3.3 pCi/L
Radford city24 of 849841.8%3.2 pCi/L
Rappahannock County25 of 8413741.6%3.3 pCi/L
Tazewell County26 of 8437240.3%2.8 pCi/L
Rockingham County ten-year laboratory totals, against Virginia's pooled share
PeriodTestsAt or above 4 pCi/LMedianHighestVirginia, pooledChange from the row before
2008 to 20171,71443.9%3.3 pCi/L88.8 pCi/L30.4%Level
2007 to 20161,63943.9%3.3 pCi/L88.8 pCi/L30.6%+0.3 points
2006 to 20151,52743.6%3.3 pCi/L88.8 pCi/L30.7%−0.2 points
2005 to 20141,31143.8%3.4 pCi/L88.8 pCi/L30.3%First on file

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

Rockingham County, Geology

The ground under Rockingham County

Predicted

Most of the ground under Rockingham County is one class on USGS's geologic map: 95.2% of its land is high radon potential, with 4.8% moderate. 95.0% of it lies in the area the map calls Valley and Ridge, to which USGS gives a radon index of 15, in the high band (12 to 17).

USGS's geologic areas under Rockingham County
AreaThe rock, in USGS's wordsPotentialRadon indexShare of land
Valley and RidgeCambrian dolomite, limestone, shale, and sandstone, Silurian-Ordovician limestone, dolomite, shale, and sandstone, Mississippian-Devonian sandstone, shale, limestone, gypsum, and coal.High1595.0%
Blue RidgeGranite, pegmatite, monazite, schist, and gneiss.Moderate104.8%

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

Rockingham County beside the ground around it

Rockingham County has more high-potential ground than Virginia as a whole: 95.2% of its land against 47.9%. Of the 8 counties that border it, 4 have more high-potential ground, Harrisonburg city the most at 100%.

Share of land by USGS radon potential: Rockingham County, the 8 counties bordering it and Virginia
AreaEPA zoneLow potentialModerate potentialHigh potential
Rockingham CountyZone 1None4.8%95.2%
Harrisonburg cityZone 1NoneNone100%
Page CountyZone 1None31.2%68.8%
Pendleton County, WVZone 1None1.9%98.1%
Shenandoah CountyZone 1NoneNone100%
Greene CountyZone 2None100%None
Hardy County, WVZone 1NoneNone100%
Augusta CountyZone 1None4.9%95.1%
Albemarle CountyZone 2None71.1%28.9%
Virginia133 counties, pooled by land areaVaries20.6%30.0%47.9%

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

Local help

Rockingham County, Local resources

Radon testing and mitigation in Rockingham County

What Virginia's program says
Phone
(804) 864-8161
Email
Radon@vdh.virginia.gov
Licensing of radon professionals
The Code of Virginia requires that Radon testers and mitigators be currently certified by either the National Radon Proficiency Program (NRPP) or the National Radon Safety Board (NRSB).

What it means

Rockingham County, Questions

Questions about radon in Rockingham County

Are radon levels high in Rockingham County?

Over the 2008 to 2017 laboratory totals, 43.9% of the radon tests reported to CDC for Rockingham County, Virginia were at or above 4 pCi/L, and the median reported pre-mitigation result was 3.3 pCi/L. Of 84 Virginia counties with 30 or more tests for the same period, 20 reported a higher share; pooled, the state comes to 30.4%.

Which counties border Rockingham County?

Rockingham County borders 8 counties: Harrisonburg city, VA, Page County, VA, Pendleton County, WV, Shenandoah County, VA, Greene County, VA, Hardy County, WV, Augusta County, VA and Albemarle County, VA.

Products

Rockingham County, Products

Testing a home in Rockingham County

In Rockingham County, 43.9% of 1,714 tests reported to CDC over the 2008 to 2017 laboratory totals reached 4 pCi/L, against 30.4% pooled across Virginia. In Zone 1 the year-round level in Rockingham County is the one to know: a long-term test (more than 90 days) or a monitor, with a short-term kit for a first answer.

Test kits and monitors3

See every kit and monitor

Rockingham County is in EPA Zone 1, the highest predicted radon potential. Best radon monitors for Zone 1 counties like Rockingham County

Explore

Rockingham County, Bordering counties

Counties bordering Rockingham County

Calculated by Radon411

Rockingham County, Cities and towns

Cities and towns in Rockingham County

Rockingham County is growing: the Census Bureau puts it at 89,316 residents on July 1, 2025, up 6.6% from 83,780 in 2020. That works out to 105 people per square mile of land. No town dominates: Bridgewater, the largest, has 6,924 residents, 7.8% of the total. Testing is reported here more often than across the state: CDC's 1,714 reported tests for 2008 to 2017 come to 19.2 for every 1,000 residents (2025 estimate), against 6.0 for Virginia.

From Bridgewater to Mount Crawford, CDC publishes no figure by town: each reads Rockingham County's.

The cities and towns in Rockingham County by residents, July 1, 2025
PlaceResidentsSince 2020Share of residents
Bridgewater6,924+5.0%7.8%
Broadway4,463+6.8%5.0%
Timberville3,166+6.6%3.5%
Elkton3,136+6.3%3.5%
Grottoesextends beyond Rockingham County3,099+6.6%Counted whole
Dayton1,791+6.4%2.0%
Mount Crawford476+7.0%0.5%

7 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 Rockingham County is counted whole, so it has no share.

Rockingham County, Homes

Homes in Rockingham County

Of Rockingham County's 36,095 homes, 71% are detached houses, against 61% across Virginia; 9% are mobile homes. Half of its homes were built before 1986, close to Virginia's 1984: 21% date from before 1960 and 28% from 2000 or later. Owners live in 75% of the occupied homes (Virginia: 67%), so for most households a test and a fix are their own to order.

Homes in Rockingham County, Virginia, 2019 to 2023
HomesRockingham CountyVirginia
Housing units36,0953,654,784
Detached houses71%61%
In buildings of 5 or more5%19%
Mobile homes9%4%
Built before 196021%19%
Built since 200028%25%
Middle year built19861984
Owner-occupied75%67%

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