Short-term kitKidde
442020 short-term charcoal radon test kit
- Lab fee included
Method: Charcoal
In home: 3 days
Locations and reports
Radon Levels in Arlington County, Virginia
EPA puts Arlington County in Zone 2, its middle radon zone, and most reported tests there come back low, though 13.7% of 1,101 (2008 to 2017, laboratory totals) reached 4 pCi/L. Homes with elevated levels occur in all three zones, so only a test measures yours.
Data checked By Radon411Methodology
Share at 4+ pCi/L
13.7%
16.7 pts below VA
- Arlington
- 13.7%
- Virginia
- 30.4%
1,101 tests, 2008 to 2017
Median result
1.4pCi/L
Below action level
- Arlington
- 1.4 pCi/L
- EPA
- 4.0 pCi/L
Midpoint of the tests, 2008 to 2017
Tests reported
1,101
11th of 84 by tests
- Arlington
- 1,101
- Fairfax
- 8,657
Reported to CDC before any fix, 2008 to 2017
EPA radon zone
Zone 2
Moderate potential
- 1
- Zone 2
- 3
1 highest, 3 lowest
EPA predicts 2 to 4 pCi/L indoors
Rank in Virginia
77 of 84
Lowest quarter
- Arlington
- 13.7%
- Russell
- 67.3%
By share, of 84 with 30+ tests
Read a result for Arlington County
Starts at Arlington County's median, 1.4 pCi/L
EPA’s own thresholds; the figures are the area’s, never this home’s.
EPA’s reading of 1.4 pCi/L
Below 2 pCi/L
- Under 20 to 1.9 pCi/L
- 2 to 4consider a fix
- 4 and aboveEPA says fix it
This result is below 2 pCi/L, the level at which EPA says a fix should be considered. Arlington County's median reported result, 2008 to 2017.
The data
Arlington County, At a glance
Arlington County at a glance
Predicted: EPA radon zone
EPA Zone 2: moderate predicted potential
Arlington County is a
USGS geologic potential: Low across 55% of the county's area
Predicted: EPA Map of Radon Zones
Measured: tests reported to CDC
Radon tests reported for Arlington County, 2008 to 2017, laboratory
Under 2 pCi/L: 61%2 to 4 pCi/L: 25%4 pCi/L and above: 14%
Of 1,101 pre-mitigation tests reported to CDC, not homes in this area.
| Result band | Tests Measured | Share Measured |
|---|---|---|
| Under 2 pCi/L | 677 | 61.5% |
| 2 to 4 pCi/L | 273 | 24.8% |
| 4 pCi/L and above | 151 | 13.7% |
What these figures count
These are the 1,101 tests reported to CDC for Arlington 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).
Arlington County, Compared
Arlington County radon figures, compared
Calculated by Radon411Arlington County reports fewer high tests than Virginia overall. 13.7% of its 1,101 tests over the 2008 to 2017 laboratory totals were at or above 4 pCi/L. That is 16.7 points below the 30.4% pooled from 131 Virginia counties.
Ordered from highest share down, it comes 77th of 84 Virginia counties with 30 or more tests for the same period. Nationally, every county with a figure for the same period pools to 35.7%; Arlington County sits 22.0 points below it.
Next door, the shares run from 7.3% in Alexandria city to 18.7% in Fairfax County, with District of Columbia, DC and Alexandria city below Arlington County. Zone 2 on EPA's map (predicted average between 2 and 4 pCi/L) and a 13.7% share point the same way here.
Half the tests came in under 1.4 pCi/L and half over it; the single highest reached 29.4 pCi/L. The rest split 61.5% under 2 pCi/L and 24.8% from 2 to 4 (Virginia: 44.7% and 24.9%).
CDC's ten-year totals for Arlington County went from 812 tests (2005 to 2014) to 1,101 (2008 to 2017), the share going from 13.1% to 13.7%.
Pooled shares: Radon411's sum of CDC's county counts for one period.
Arlington County, Geology
The ground under Arlington County
PredictedUSGS's geologic map splits Arlington County: 54.9% of its land is low radon potential and 44.8% high. The map puts 54.9% of Arlington County in the area it calls Cretaceous Coastal Plain Sediments and 44.7% in Inner Piedmont. USGS gives the first a radon index of 8, in the low band (5 to 8), and the second 12, in the high band (12 to 17).
| Area | The rock, in USGS's words | Potential | Radon index | Share of land |
|---|---|---|---|---|
| Cretaceous Coastal Plain Sediments | Cretaceous Coastal Plain sand, silt, clay. | Low | 8 | 54.9% |
| Inner Piedmont | Granite, pegmatites, granitic gneiss, schist and gneiss, slate, and phyllite. | High | 12 | 44.7% |
Names, descriptions and indexes: U.S. Geological Survey, Geologic Radon Potential Map (2025). Shares: Radon411, from the map cut to the boundary.
Arlington County beside the ground around it
On high-potential ground Arlington County is close to Virginia as a whole: 44.8% of its land against 47.9%. Of the 4 counties that border it, 2 have more high-potential ground, Montgomery County, MD the most at 80.2%.
The map rates the ground, not the air in any home.
Local help
Arlington County, Local resources
Radon testing and mitigation in Arlington County
- VDH Radon ProgramVDH Radon Program answers questions about testing, mitigation and the rules in Virginia.Visit the program’s page(opens in a new tab)
- Free and low-cost kitsAsk the program whether it has free or discounted kits, or compare kits you can buy.
- Compare kits
- Professionals in Virginia2 professionals are listed in Virginia.
What Virginia's program says
- Phone
- (804) 864-8161
- 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
Arlington County, Questions
Questions about radon in Arlington County
Are radon levels high in Arlington County?
Over the 2008 to 2017 laboratory totals, 13.7% of the radon tests reported to CDC for Arlington County, Virginia were at or above 4 pCi/L, and the median reported pre-mitigation result was 1.4 pCi/L. Of 84 Virginia counties with 30 or more tests for the same period, 76 reported a higher share; pooled, the state comes to 30.4%.
Which counties border Arlington County?
Arlington County borders 4 counties: Alexandria city, VA, District of Columbia, DC, Fairfax County, VA and Montgomery County, MD.
Products
Arlington County, Products
Testing a home in Arlington County
In Arlington County, 13.7% of 1,101 tests reported to CDC over the 2008 to 2017 laboratory totals reached 4 pCi/L, against 30.4% pooled across Virginia. In Zone 2 a short-term kit (2 to 90 days) is the quick first check in Arlington County; a long-term test tells the year-round average.
Test kits and monitors3
See every kit and monitor
Long-term kit
RL416 long-term radon test kit, lab fee included
- Lab fee included
Method: Alpha track
In home: 90 days to 12 months
Monitor
View Radon Wi-Fi radon monitor with an e-paper display
- C-NRPP 2024/25: Approved
- Battery
- Wi-Fi, Bluetooth
- Screen, app
Method: Alpha spectrometry
Readings: Every 60 minutes
- See every kit and monitor Test kits and monitors
Test kits and monitors: 1 of 3
Explore
Arlington County, Bordering counties
Counties bordering Arlington County
Calculated by Radon411- Radon levels in Fairfax County, VAEPA zone 1
18.7%at or above 4 pCi/L
Median 1.5 pCi/L · 8,657 tests · 5.0 points above Arlington County
- Radon levels in Montgomery County, MDEPA zone 1
18.0%at or above 4 pCi/L
Median 1.3 pCi/L · 10,969 tests · 4.3 points above Arlington County
- Radon levels in District of Columbia, DCEPA zone 3
8.7%at or above 4 pCi/L
Median 1.2 pCi/L · 2,126 tests · 5.0 points below Arlington County
- Radon levels in Alexandria city, VAEPA zone 3
7.3%at or above 4 pCi/L
Median 1.0 pCi/L · 410 tests · 6.4 points below Arlington County
Arlington County, Residents
Who lives in Arlington County
The Census Bureau estimates 243,931 residents in Arlington County for July 1, 2025, 5,106 more than in 2020 (+2.1%). Packed into its land, that is 9,383 people per square mile. CDC's 1,101 reported tests for 2008 to 2017 work out to 4.5 per 1,000 residents (2025 estimate), close to Virginia's 6.0.
Census lists no incorporated place in Arlington County: every home in it reads the county's figures.
Residents: U.S. Census Bureau population estimates for July 1, 2025 (Vintage 2025).
Arlington County, Homes
Homes in Arlington County
Arlington County has 120,746 homes, and many share a building: 61% are in buildings of five or more, 25% are detached houses, against 61% across Virginia. The homes are older than Virginia's as a whole: half were built before 1976 (1984 for Virginia), and 33% date from before 1960. Most occupied homes here are rented: owners live in 42% (Virginia: 67%). A tenant can run a test; a fix is the landlord's to make.
| Homes | Arlington County | Virginia |
|---|---|---|
| Housing units | 120,746 | 3,654,784 |
| Detached houses | 25% | 61% |
| In buildings of 5 or more | 61% | 19% |
| Mobile homes | under 1% | 4% |
| Built before 1960 | 33% | 19% |
| Built since 2000 | 27% | 25% |
| Middle year built | 1976 | 1984 |
| Owner-occupied | 42% | 67% |
Census Bureau, American Community Survey, 2019 to 2023: estimates from a sample of homes, looser for a small place. Shares by Radon411.