Long-term kit
RL116 long-term radon test kit
- Lab fee extra
Method: Alpha track
In home: 90 days to 12 months
Locations and reports
Radon Levels in Manassas city, Virginia
EPA puts Manassas city in Zone 1, its highest radon zone, and 15.9% of its 145 reported radon tests (2008 to 2017, laboratory totals) were 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
Share at 4+ pCi/L
15.9%
14.5 pts below VA
- Manassas city
- 15.9%
- Virginia
- 30.4%
145 tests, 2008 to 2017
Median result
1.9pCi/L
Below action level
- Manassas city
- 1.9 pCi/L
- EPA
- 4.0 pCi/L
Midpoint of the tests, 2008 to 2017
Tests reported
145
49th of 84 by tests
- Manassas city
- 145
- Fairfax
- 8,657
Reported to CDC before any fix, 2008 to 2017
EPA radon zone
Zone 1
Highest potential
- Zone 1
- 2
- 3
1 highest, 3 lowest
EPA predicts over 4 pCi/L indoors
Rank in Virginia
75 of 84
Lowest quarter
- Manassas city
- 15.9%
- Russell
- 67.3%
By share, of 84 with 30+ tests
Read a result for Manassas city
Starts at Manassas city's median, 1.9 pCi/L
EPA’s own thresholds; the figures are the area’s, never this home’s.
EPA’s reading of 1.9 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. Manassas city's median reported result, 2008 to 2017.
The data
Manassas city, At a glance
Manassas city at a glance
Predicted: EPA radon zone
EPA Zone 1: highest predicted potential
EPA puts all of Manassas city in
USGS geologic potential: Moderate across 60% of the county's area
Predicted: EPA Map of Radon Zones
Measured: tests reported to CDC
Radon tests reported for Manassas city, 2008 to 2017, laboratory
Under 2 pCi/L: 54%2 to 4 pCi/L: 30%4 pCi/L and above: 16%
Of 145 pre-mitigation tests reported to CDC, not homes in this area.
| Result band | Tests Measured | Share Measured |
|---|---|---|
| Under 2 pCi/L | 79 | 54.5% |
| 2 to 4 pCi/L | 43 | 29.7% |
| 4 pCi/L and above | 23 | 15.9% |
What these figures count
These are the 145 tests reported to CDC for Manassas city 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).
Manassas city, Compared
Manassas city radon figures, compared
Calculated by Radon411Manassas city's 145 reported tests over the 2008 to 2017 laboratory totals had a middle value of 1.9 pCi/L and a maximum of 39.8 pCi/L, and 15.9% reached 4 pCi/L. Virginia as a whole (131 Virginia counties, pooled) comes to 30.4%: 14.5 points higher than here.
Among its state's counties it ranks 75th of 84 Virginia counties with 30 or more tests for the same period. Statewide for the same period, Russell County reported the highest share (67.3%) and Norfolk city the lowest (2.7%).
Below the action level, 79 tests (54.5%) came in under 2 pCi/L, against 44.7% statewide, and 43 tests (29.7%) fell between 2 and 4, against 24.9% statewide. CDC's ten-year totals for Manassas city went from 81 tests (2005 to 2014) to 145 (2008 to 2017), the share going from 11.1% to 15.9%.
EPA's 1993 zone map puts Manassas city in Zone 1, a predicted county average above 4 pCi/L. USGS geology rates 60% of the county's land moderate radon potential.
Prince William County, the one bordering county with a figure for the same period, reported 31.7%.
CDC also counts 12 tests taken after mitigation in Manassas city for the same period: tests in homes where a fix was already in.
Pooled shares: Radon411's sum of CDC's county counts for one period.
Manassas city, Geology
The ground under Manassas city
PredictedUSGS's geologic map splits Manassas city: 60.0% of its land is moderate radon potential and 40.0% high. The map puts 60.0% of Manassas city in the area it calls Mesozoic Basins and 40.0% in Inner Piedmont. USGS gives the first a radon index of 11, in the moderate band (9 to 11), and the second 12, in the high band (12 to 17).
| Area | The rock, in USGS's words | Potential | Radon index | Share of land |
|---|---|---|---|---|
| Mesozoic Basins | Sandstone, siltstone and lacustrine black shale. | Moderate | 11 | 60.0% |
| Inner Piedmont | Granite, pegmatites, granitic gneiss, schist and gneiss, slate, and phyllite. | High | 12 | 40.0% |
Names, descriptions and indexes: U.S. Geological Survey, Geologic Radon Potential Map (2025). Shares: Radon411, from the map cut to the boundary.
Manassas city beside the ground around it
On high-potential ground Manassas city is close to Virginia as a whole: 40.0% of its land against 47.9%. Every one of the 2 counties that border it has more high-potential ground, Manassas Park city the most at 77.7%.
The map rates the ground, not the air in any home.
Local help
Manassas city, Local resources
Radon testing and mitigation in Manassas city
- 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
Manassas city, Questions
Questions about radon in Manassas city
Are radon levels high in Manassas city?
Over the 2008 to 2017 laboratory totals, 15.9% of the radon tests reported to CDC for Manassas city, Virginia were at or above 4 pCi/L, and the median reported pre-mitigation result was 1.9 pCi/L. Of 84 Virginia counties with 30 or more tests for the same period, 74 reported a higher share; pooled, the state comes to 30.4%.
Which counties border Manassas city?
Manassas city borders 2 counties: Manassas Park city and Prince William County.
Products
Manassas city, Products
Testing a home in Manassas city
In Manassas city, 15.9% of 145 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 Manassas city 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
MonitorForensics Detectors
FD-65-RADON rechargeable radon detector with a color screen
- C-NRPP 2024/25: Not included
- Battery
- Alarm
- Screen
Method: Semiconductor sensor
First reading: Within 6 hours
Short-term kitempowerDX
Standard Radon Test short-term mail-in radon test kit
- Lab fee included
Method: Passive sampler
In home: 48 to 96 hours
- See every kit and monitor Test kits and monitors
Test kits and monitors: 1 of 3
Manassas city is in EPA Zone 1, the highest predicted radon potential. Best radon monitors for Zone 1 counties like Manassas city
Explore
Manassas city, Bordering counties
Counties bordering Manassas city
Calculated by Radon411- Radon levels in Prince William CountyEPA zone 2
31.7%at or above 4 pCi/L
Median 2.3 pCi/L · 4,441 tests · 15.8 points above Manassas city
- Radon levels in Manassas Park cityEPA zone 1
20.0%at or above 4 pCi/L
Median 1.4 pCi/L · 25 tests · 4.1 points above Manassas city
Manassas city, Cities and towns
Cities and towns in Manassas city
The Census Bureau estimates 44,332 residents in Manassas city for July 1, 2025, 1,642 more than in 2020 (+3.8%). Packed into its land, that is 4,504 people per square mile. Manassas, its one incorporated place, has 44,332 residents, 100.0% of the total. Reported testing is thin here: 145 tests over 2008 to 2017, or 3.3 for every 1,000 residents (2025 estimate), where Virginia as a whole comes to 6.0.
Manassas is the one incorporated place here; CDC publishes no figure by town, so it reads Manassas city's.
| Place | Residents | Since 2020 | Share of residents |
|---|---|---|---|
| Manassas | 44,332 | +3.8% | 100.0% |
One incorporated place, 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).
Manassas city, Homes
Homes in Manassas city
Fewer than six in ten of Manassas city's 14,426 homes are detached houses (44%, against 61% across Virginia); the rest are attached, in shared buildings or mobile. Half of its homes were built before 1985, close to Virginia's 1984: 7% date from before 1960 and 16% from 2000 or later. 72% of occupied homes are lived in by their owner (Virginia: 67%); in the rest a tenant can run a test, but a fix is the landlord's to make.
| Homes | Manassas city | Virginia |
|---|---|---|
| Housing units | 14,426 | 3,654,784 |
| Detached houses | 44% | 61% |
| In buildings of 5 or more | 20% | 19% |
| Mobile homes | 1% | 4% |
| Built before 1960 | 7% | 19% |
| Built since 2000 | 16% | 25% |
| Middle year built | 1985 | 1984 |
| Owner-occupied | 72% | 67% |
Census Bureau, American Community Survey, 2019 to 2023: estimates from a sample of homes, looser for a small place. Shares by Radon411.