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Radon Levels in Passaic County, New Jersey

EPA puts Passaic County in Zone 2, its middle radon zone, and most reported tests there come back low, though 7.5% of 4,825 (2022) reached 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

    7.5%

    2.2 pts below NJ

    Passaic
    7.5%
    New Jersey
    9.7%

    4,825 tests, 2022

  • Median result

    0.8pCi/L

    Below action level

    Passaic
    0.8 pCi/L
    EPA
    4.0 pCi/L

    Midpoint of the tests, 2022

  • Tests reported

    4,825

    11th of 21 by tests

    Passaic
    4,825
    Bergen
    11,440

    Reported to CDC before any fix, 2022

  • EPA radon zone

    Zone 2

    Moderate potential

    1. 1
    2. Zone 2
    3. 3

    1 highest, 3 lowest

    EPA predicts 2 to 4 pCi/L indoors

  • Rank in New Jersey

    11 of 21

    Middle half

    Passaic
    7.5%
    Warren
    24.6%

    By share, of 21 with 30+ tests

Read a result for Passaic County

Starts at Passaic County's median, 0.8 pCi/L

0.8pCi/L

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

EPA’s reading of 0.8 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. Passaic County's median reported result, 2022.

Interpret this reading

The data

Passaic County, At a glance

Passaic County at a glance

Predicted: EPA radon zone

EPA Zone 2: moderate predicted potential

Passaic County is a county: EPA's forecast for it as a whole is an average indoor of 2 to 4 pCi/L (75 to 150 Bq/m³). It describes no single address, and homes above EPA's are found in every zone, this one included.

USGS geologic potential: High across 64% of the county's area

Predicted: EPA Map of Radon Zones

Measured: tests reported to CDC

Radon tests reported for Passaic County, 2022

Reported results by concentration band, Passaic County, 2022
Under 2 pCi/L: 78%2 to 4 pCi/L: 15%4 pCi/L and above: 7%

Of 4,825 pre-mitigation tests reported to CDC, not homes in this area.

Reported results by concentration band, Passaic County, 2022: data table
Result bandTests MeasuredShare Measured
Under 2 pCi/L3,75177.7%
2 to 4 pCi/L71214.8%
4 pCi/L and above3627.5%
What these figures count

These are the 4,825 tests reported to CDC for Passaic County over 2022, many from homes being sold or already suspected of a problem: they describe the county's reported tests, not this house.

The figures at the top are for 2022: a percentage there is a share of radon tests reported to CDC for Passaic County in 2022, and a percentage in a view below is a share of the tests reported for the year or period it names. It is not a share of homes in Passaic County, and it is not a random sample: it counts only the tests people chose to run and that were reported.

CDC works out the shares and the median over pre-mitigation tests, counting a test not marked as before or after mitigation as one of them (4,825 for 2022). The median is the middle result of those tests, not of buildings. CDC also reports the number of buildings tested (3,085), a different count, so the two totals are not interchangeable.

Measured: CDC tracking data. Figure above: 2022. Measured data period: 2014 to 2022 (every CDC figure on file).

How to read these figures

Passaic County, Compared

Passaic County radon figures, compared

Calculated by Radon411

Passaic County reports fewer high tests than New Jersey overall. 7.5% of its 4,825 tests in 2022 were at or above 4 pCi/L. That is 2.2 points below the 9.7% pooled from 21 New Jersey counties.

Ordered from highest share down, it comes 11th of 21 New Jersey counties with 30 or more tests for the same period. Nationally, every county with a figure for the same period pools to 23.9%; Passaic County sits 16.4 points below it.

Next door, the shares run from 4.1% in Essex County to 22.3% in Sussex County, with Bergen County and Essex County below Passaic County. The reported tests do not follow EPA's Zone 2 label for Passaic County (predicted average between 2 and 4 pCi/L): 7.5% of them reached 4 pCi/L, fewer than that label suggests.

Half the tests came in under 0.8 pCi/L and half over it; the single highest reached 41.9 pCi/L. The rest split 77.7% under 2 pCi/L and 14.8% from 2 to 4 (New Jersey: 74.9% and 15.4%). Year by year, 2014 opened at 10.6% and 2022 closed at 7.5% (down 3.1 points), with 2014 the high at 10.6%.

The busiest year on file was 2021, with 6,470 tests reported; the quietest, 2014, had 4,066.

Share of reported tests at or above 4 pCi/L by year, Passaic County against New Jersey2014 to 2022, years with 30 or more tests: Passaic County 10.6% to 7.5%, the state's pooled share 9.7% in 2022.
Passaic CountyNew Jersey, pooled
Share of reported tests at or above 4 pCi/L by year, Passaic County against New Jersey: data table
YearTestsPassaic County, at or above 4 pCi/LNew Jersey, pooled
20144,06610.6%12.8%
20154,7119.5%12.5%
20164,8168.3%12.5%
20175,0689.2%11.9%
20185,6788.6%11.0%
20195,1398.3%11.2%
20206,0229.6%11.7%
20216,4707.5%10.3%
20224,8257.5%9.7%
Passaic County against New Jersey, the United States and nearby counties, 2022
AreaTestsAt or above 4 pCi/LMedianDifference from Passaic County
Passaic County4,8257.5%0.8 pCi/LThis county
New Jersey, pooled21 counties, pooled108,9349.7%Not pooled+2.2 points
United States, pooled853 counties, pooled333,14023.9%Not pooled+16.4 points
Warren Countyhighest in the state2,81924.6%1.5 pCi/L+17.1 points
Cape May Countylowest in the state2460.0%0.3 pCi/L−7.5 points
Sussex County, NJborders it4,11622.3%1.5 pCi/L+14.8 points
Morris County, NJborders it10,93913.6%1.1 pCi/L+6.1 points
Bergen County, NJborders it11,4406.1%1.0 pCi/L−1.4 points
Essex County, NJborders it8,3414.1%0.7 pCi/L−3.4 points
Rockland County, NYborders it30.0%0.9 pCi/L−7.5 points
Where Passaic County's reported results fell, 2022, beside New Jersey and the United States
ResultPassaic County testsPassaic County shareNew Jersey shareU.S. shareAgainst New Jersey
Under 2 pCi/L3,75177.7%74.9%54.5%+2.8 points
2 to 4 pCi/L71214.8%15.4%21.7%−0.6 points
4 pCi/L and above3627.5%9.7%23.9%−2.2 points
Passaic County ranked among the 21 New Jersey counties with 30 or more tests, by share at or above 4 pCi/L, 2022
CountyRankTestsAt or above 4 pCi/LMedian
Gloucester County6 of 213,33312.2%1.1 pCi/L
Salem County7 of 2145410.8%1.1 pCi/L
Mercer County8 of 216,37010.6%0.9 pCi/L
Monmouth County9 of 219,7459.8%0.7 pCi/L
Cumberland County10 of 217528.6%0.9 pCi/L
Passaic County11 of 214,8257.5%0.8 pCi/L
Middlesex County12 of 219,5947.3%0.8 pCi/L
Camden County13 of 216,7616.7%0.9 pCi/L
Burlington County14 of 215,3556.2%0.9 pCi/L
Bergen County15 of 2111,4406.1%1.0 pCi/L
Union County16 of 216,1115.1%0.9 pCi/L
Passaic County radon tests by year, against New Jersey's pooled share
YearTestsAt or above 4 pCi/LMedianHighestNew Jersey, pooledChange from the row before
20224,8257.5%0.8 pCi/L41.9 pCi/L9.7%Level
20216,4707.5%0.8 pCi/L116.4 pCi/L10.3%−2.1 points
20206,0229.6%0.9 pCi/L1388.9 pCi/L11.7%+1.3 points
20195,1398.3%1.1 pCi/L172.2 pCi/L11.2%−0.3 points
20185,6788.6%0.9 pCi/L252.4 pCi/L11.0%−0.6 points
20175,0689.2%1.0 pCi/L40.4 pCi/L11.9%+0.9 points
20164,8168.3%1.0 pCi/L66.9 pCi/L12.5%−1.2 points
20154,7119.5%1.0 pCi/L46.9 pCi/L12.5%−1.1 points
20144,06610.6%1.1 pCi/L77.7 pCi/L12.8%First on file

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

Passaic County, Geology

The ground under Passaic County

Predicted

USGS's geologic map splits Passaic County: 64.3% of its land is high radon potential and 35.7% low. The map puts 42.9% of Passaic County in the area it calls Highlands and 35.7% in Northern Piedmont, with one smaller area beside them. USGS gives the first a radon index of 15, in the high band (12 to 17), and the second 8, in the low band (5 to 8).

USGS's geologic areas under Passaic County
AreaThe rock, in USGS's wordsPotentialRadon indexShare of land
HighlandsGlacial deposits, granite, pegmatites, and gneiss.High1542.9%
Northern PiedmontSandstone, conglomerate, basalt, and shale.Low835.7%
Green Pond OutlierConglomerate, sandstone, shale, glacial depositsHigh1521.3%

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

Passaic County beside the ground around it

Passaic County has more high-potential ground than New Jersey as a whole: 64.3% of its land against 29.8%. Of the 6 counties that border it, 3 have more high-potential ground, Orange County, NY the most at 100%.

Share of land by USGS radon potential: Passaic County, the 6 counties bordering it and New Jersey
AreaEPA zoneLow potentialModerate potentialHigh potential
Passaic CountyZone 235.7%None64.3%
Essex CountyZone 299.4%NoneNone
Bergen CountyZone 297.4%None2.6%
Morris CountyZone 121.8%None78.2%
Rockland County, NYZone 356.1%8.1%35.8%
Sussex CountyZone 1None19.4%80.6%
Orange County, NYZone 1NoneNone100%
New Jersey21 counties, pooled by land areaVaries53.8%13.8%29.8%

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

Local help

Passaic County, Local resources

Local resources in New Jersey

Who to ask in New Jersey: its radon program, test kits and professionals.

What New Jersey's program says
Phone
800-648-0394
Licensing of radon professionals
By law, all businesses and professionals conducting radon testing and mitigation in New Jersey must be certified by the DEP.
Disclosure when a home is sold or rented
Under the law, the seller must provide the buyer, at the time the contract of sale is entered into, with a copy of the results of the radon test and evidence of any mitigation or treatment.

What it means

Passaic County, Questions

Questions about radon in Passaic County

Are radon levels high in Passaic County?

In 2022, 7.5% of the radon tests reported to CDC for Passaic County, New Jersey were at or above 4 pCi/L, and the median reported pre-mitigation result was 0.8 pCi/L. That is a share of reported tests, not of homes. EPA places Passaic County in Zone 2, moderate predicted potential, a predicted average indoor screening level 2 to 4 pCi/L. Homes with elevated levels occur in all three zones, so the figures describe the area, not your house. Testing is the only way to know the radon level in a specific building.

What a radon level meansRadon in New Jersey

How do I get a radon test in Passaic County?

EPA says you can test your home yourself or hire a qualified radon test company. No radon testing business listed on Radon411 has an address in Passaic County or names it as a service area yet. The New Jersey radon program is the place to ask about certified testers and any test kit offer it runs.

How to test a homeTest kits comparedFree and low-cost kits by stateRadon Action Month checklistNew Jersey radon program

Who does radon mitigation in Passaic County?

No listed mitigator names Passaic County as a service area yet; the New Jersey directory lists 15 companies. EPA recommends a qualified contractor for the fix, and some states require a licensed or certified professional. Your state radon program is the place to check whether New Jersey requires one.

How radon mitigation worksWhat mitigation costsMitigators in New Jersey

What EPA radon zone is Passaic County in?

EPA places Passaic County, New Jersey in Zone 2, which EPA describes as moderate predicted potential for the area. A zone is a prediction for the whole county and never determines whether a particular home should be tested. EPA recommends testing every home regardless of zone.

Should I test my home in Passaic County?

Yes. In 2022, 7.5% of the radon tests reported to CDC for Passaic County, New Jersey were at or above 4 pCi/L, and the median reported pre-mitigation result was 0.8 pCi/L. That is a share of reported tests, not of homes. Testing is the only way to know the radon level in a specific building. EPA recommends fixing a home when the radon level is 4 pCi/L or higher. How to test a home, what testing costs.

Which counties border Passaic County?

Passaic County borders 6 counties: Essex County, NJ, Bergen County, NJ, Morris County, NJ, Rockland County, NY, Sussex County, NJ and Orange County, NY. Radon potential follows geology rather than county lines, so a bordering county's report can be relevant.

Products

Passaic County, Products

Testing a home in Passaic County

In Passaic County, 7.5% of 4,825 tests reported to CDC in 2022 reached 4 pCi/L, against 9.7% pooled across New Jersey. In Zone 2 a short-term kit (2 to 90 days) is the quick first check in Passaic County; a long-term test tells the year-round average.

Test kits and monitors3

See every kit and monitor

Best radon monitors for Passaic County homes, compared

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Passaic County, Bordering counties

Counties bordering Passaic County

Calculated by Radon411

Passaic County, Cities and towns

Cities and towns in Passaic County

The Census Bureau estimates 531,624 residents in Passaic County for July 1, 2025, 8,468 more than in 2020 (+1.6%). Packed into its land, that is 2,858 people per square mile. Its largest town, Paterson, has 161,793 residents, 30.4% of the total. Together its 13 incorporated places hold 82.1% of those residents; the other 17.9% live outside any of them. CDC's 4,825 reported tests for 2022 work out to 9.1 per 1,000 residents (2025 estimate), close to New Jersey's 11.4.

From Paterson to Prospect Park, CDC publishes no figure by town: each reads Passaic County's.

The 12 largest cities and towns in Passaic County by residents, July 1, 2025
PlaceResidentsSince 2020Share of residents
Paterson161,793+1.6%30.4%
Clifton91,127+1.8%17.1%
Passaic71,337+1.5%13.4%
Hawthorne20,169+3.1%3.8%
Woodland Park13,623+1.3%2.6%
Ringwood11,853+1.4%2.2%
Wanaque11,418+1.9%2.1%
Pompton Lakes11,246+1.4%2.1%
Totowa11,166+1.3%2.1%
Haledon9,125+1.3%1.7%
North Haledon9,089+2.0%1.7%
Bloomingdale7,853+1.5%1.5%
  • Prospect Park

13 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).

Passaic County, Homes

Homes in Passaic County

Fewer than six in ten of Passaic County's 185,439 homes are detached houses (42%, against 53% across New Jersey); the rest are attached, in shared buildings or mobile. The homes are older than New Jersey's as a whole: half were built before 1956 (1969 for New Jersey), and 57% date from before 1960. 53% of occupied homes are lived in by their owner (New Jersey: 64%); in the rest a tenant can run a test, but a fix is the landlord's to make.

Homes in Passaic County, New Jersey, 2019 to 2023
HomesPassaic CountyNew Jersey
Housing units185,4393,775,842
Detached houses42%53%
In buildings of 5 or more21%22%
Mobile homesunder 1%1%
Built before 196057%38%
Built since 20009%15%
Middle year built19561969
Owner-occupied53%64%

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