Skip to content
RADON411

Locations and reports

Radon Levels in Philadelphia County, Pennsylvania

EPA puts Philadelphia County in Zone 3, its lowest radon zone. Homes with elevated levels occur in all three zones, so only a test measures yours.

Data checked By Radon411Methodology

Predicted
Zone 3Lower predicted potential
Measured
10.6%of 8,442 tests reported to CDC (2020) were at or above 4 pCi/L
Your home
Test to knowNo area figure here is a reading of your home.
How to test this homeFind a certified tester

The data

Philadelphia County, At a glance

Philadelphia County at a glance

Predicted: EPA radon zone

EPA Zone 3: lower predicted potential

This is a county-level geologic prediction. It is not a measurement of any address, and houses with elevated radon are found in all three zones.

What EPA predicts hereScreening level, geology

EPA predicts an average indoor of less than 2 pCi/L (less than 75 Bq/m³) across the county as a whole.

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

Predicted: EPA Map of Radon Zones

Measured: tests reported to CDC

Radon tests reported for Philadelphia County, 2020

Tests reported
8,442
At or above 4 pCi/L
10.6%
Median result
1.7 pCi/L
Reported results by concentration band, Philadelphia County, 2020
Under 2 pCi/L: 58%2 to 4 pCi/L: 31%4 pCi/L and above: 11%

Of 8,442 pre-mitigation tests reported to CDC, not homes in this area.

Reported results by concentration band, Philadelphia County, 2020: data table
Result bandTests MeasuredShare Measured
Under 2 pCi/L4,92758.4%
2 to 4 pCi/L2,61831.0%
4 pCi/L and above89710.6%

CDC publishes this figure only for counties here, so there is no state or national number to compare Philadelphia County, Pennsylvania with.

What these figures count

Distribution of radon tests reported to CDC, not this house. People testing before a sale, or because they suspect a problem, are over-represented in any reported testing data.

The figures at the top are for 2020: a percentage there is a share of radon tests reported to CDC for Philadelphia County in 2020, 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 Philadelphia 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 (8,442 for 2020). The median is the middle result of those tests, not of buildings. CDC also reports the number of buildings tested (6,089), a different count, so the two totals are not interchangeable.

Philadelphia County's own published CDC figures beside those of the counties that border it, for the same period.

Each figure is that county’s own published CDC figure for 2020, counting radon tests reported to CDC, not homes. Philadelphia County is this page. Nothing is averaged or combined across counties. The test count beside each county is CDC’s published number of pre-mitigation tests behind its figures. Figures from few tests can swing widely from year to year. Every Pennsylvania county’s own figure is in the Pennsylvania county table.

Measured: CDC tracking data. Figure above: 2020. Measured data period: 2005 to 2020 (every CDC figure on file).

Philadelphia County, State data

Pennsylvania's own radon test data

Measured

What Pennsylvania's own agencies publish about radon tests in Philadelphia County, with their period. These are not CDC's figures and are never added to them.

MeasuredState figures, not CDC's

What Pennsylvania DEP reports for the ZIP codes in Philadelphia County

Pennsylvania DEP publishes its figures by ZIP code, not by county. These are the 49 ZIP codes that lie wholly or partly in Philadelphia County, each with the state's own figures for it. Period: Period not stated by DEP.

ZIP codes in Philadelphia County
ZIP codeWhat the state reports
19102Basement: average 1.8 pCi/L, 126 tests; First floor: figures not shown
19103Basement: average 1.9 pCi/L, 1,153 tests; First floor: average 1.0 pCi/L, 275 tests
19104Basement: average 2.2 pCi/L, 905 tests; First floor: average 1.2 pCi/L, 175 tests
19106Basement: average 2.0 pCi/L, 845 tests; First floor: average 1.2 pCi/L, 191 tests
19107Basement: average 1.5 pCi/L, 563 tests; First floor: average 0.9 pCi/L, 89 tests
19108Basement: figures not shown; First floor: figures not shown
19109Basement: figures not shown; First floor: figures not shown
19111Basement: average 2.7 pCi/L, 3,433 tests; First floor: average 1.7 pCi/L, 765 tests
19112Basement: figures not shown; First floor: figures not shown
19114Basement: average 2.4 pCi/L, 1,369 tests; First floor: average 1.3 pCi/L, 406 tests
19115Basement: average 3.3 pCi/L, 1,944 tests; First floor: average 2.2 pCi/L, 536 tests
19116Basement: average 3.4 pCi/L, 1,816 tests; First floor: average 1.9 pCi/L, 527 tests
19118Basement: average 4.5 pCi/L, 2,852 tests; First floor: average 2.4 pCi/L, 854 tests
19119Basement: average 3.1 pCi/L, 4,008 tests; First floor: average 1.7 pCi/L, 851 tests
19120Basement: average 1.5 pCi/L, 1,222 tests; First floor: average 1.0 pCi/L, 253 tests
19121Basement: average 1.7 pCi/L, 1,005 tests; First floor: average 1.0 pCi/L, 53 tests
19122Basement: average 1.6 pCi/L, 607 tests; First floor: average 1.1 pCi/L, 49 tests
19123Basement: average 2.2 pCi/L, 886 tests; First floor: average 1.4 pCi/L, 102 tests
19124Basement: average 4.6 pCi/L, 1,184 tests; First floor: average 1.8 pCi/L, 237 tests
19125Basement: average 2.1 pCi/L, 2,386 tests; First floor: average 1.3 pCi/L, 121 tests
19126Basement: average 2.3 pCi/L, 752 tests; First floor: average 1.4 pCi/L, 169 tests
19127Basement: average 2.8 pCi/L, 1,273 tests; First floor: average 1.9 pCi/L, 231 tests
19128Basement: average 3.2 pCi/L, 6,261 tests; First floor: average 2.1 pCi/L, 1,180 tests
19129Basement: average 3.0 pCi/L, 1,493 tests; First floor: average 1.5 pCi/L, 280 tests
19130Basement: average 2.0 pCi/L, 2,557 tests; First floor: average 1.2 pCi/L, 422 tests
19131Basement: average 2.1 pCi/L, 956 tests; First floor: average 1.3 pCi/L, 254 tests
19132Basement: average 1.9 pCi/L, 253 tests; First floor: figures not shown
19133Basement: average 2.4 pCi/L, 133 tests; First floor: figures not shown
19134Basement: average 1.8 pCi/L, 1,031 tests; First floor: average 1.0 pCi/L, 108 tests
19135Basement: average 1.6 pCi/L, 891 tests; First floor: average 1.4 pCi/L, 159 tests
19136Basement: average 1.7 pCi/L, 1,060 tests; First floor: average 1.5 pCi/L, 198 tests
19137Basement: average 2.0 pCi/L, 292 tests; First floor: figures not shown
19138Basement: average 1.4 pCi/L, 681 tests; First floor: average 1.2 pCi/L, 67 tests
19139Basement: average 1.7 pCi/L, 718 tests; First floor: average 1.1 pCi/L, 74 tests
19140Basement: average 1.9 pCi/L, 268 tests; First floor: average 1.0 pCi/L, 41 tests
19141Basement: average 1.5 pCi/L, 495 tests; First floor: average 1.0 pCi/L, 66 tests
19142Basement: average 1.3 pCi/L, 412 tests; First floor: average 0.8 pCi/L, 119 tests
19143Basement: average 1.7 pCi/L, 1,581 tests; First floor: average 1.2 pCi/L, 220 tests
19144Basement: average 3.2 pCi/L, 1,672 tests; First floor: average 1.6 pCi/L, 381 tests
19145Basement: average 1.5 pCi/L, 1,820 tests; First floor: average 1.2 pCi/L, 236 tests
19146Basement: average 1.8 pCi/L, 4,205 tests; First floor: average 1.2 pCi/L, 371 tests
19147Basement: average 1.9 pCi/L, 4,144 tests; First floor: average 1.2 pCi/L, 606 tests
19148Basement: average 1.9 pCi/L, 2,399 tests; First floor: average 1.1 pCi/L, 176 tests
19149Basement: average 1.6 pCi/L, 1,133 tests; First floor: average 1.4 pCi/L, 220 tests
19150Basement: average 1.9 pCi/L, 1,138 tests; First floor: average 1.4 pCi/L, 161 tests
19151Basement: average 2.6 pCi/L, 1,814 tests; First floor: average 1.3 pCi/L, 461 tests
19152Basement: average 1.9 pCi/L, 1,323 tests; First floor: average 1.4 pCi/L, 330 tests
19153Basement: average 0.9 pCi/L, 259 tests; First floor: average 0.6 pCi/L, 62 tests
19154Basement: average 1.5 pCi/L, 1,390 tests; First floor: average 1.1 pCi/L, 302 tests
  • DEP's report gives the number of tests, the highest result and the average result for each floor tested; it states no period.
  • DEP says the smartest thing to do is to test your home for radon, no matter where you live.
  • A ZIP code that crosses the county line is listed whole; its figures cover all of it.

Measured: Pennsylvania DEP data, Period not stated by DEP.

Radon Action Brief

National Radon Action MonthPre-sale

Philadelphia County's radon brief, in one dated file.

  • Your area's radon record, explained.
  • Your plan to test this week.
  • Fix costs and pros near you.

Save 64%Sale price: $8.99Price after the sale: $25Ends Jan 31Then $25

Get the Philadelphia County BriefSee a free sample

Area data, not a test of the building.

Local help

Philadelphia County, Local resources

Radon testing and mitigation in Philadelphia County

Who tests and fixes radon in Philadelphia County: listed businesses, Pennsylvania's radon program and test kits.

Listed radon businesses with an address in Philadelphia County:

Listed radon professionals by town: Philadelphia

What Pennsylvania's program says
Phone
800-237-2366
Licensing of radon professionals
The Radon Certification Act requires DEP to establish by regulation, a certification program for persons conducting radon gas and radon progeny testing, laboratory analysis and mitigation...

What it means

Philadelphia County, Questions

Questions about radon in Philadelphia County

Common questions

8 questions, answered from the figures above

Who does radon mitigation in Philadelphia County?

No listed mitigator names Philadelphia County as a service area yet; the Pennsylvania directory lists 153 companies. EPA recommends having a qualified contractor fix a home with a radon problem, because lowering high radon levels takes technical knowledge and special skills, and some states require the work to be done by a licensed or certified professional. Your state radon program is the place to check whether Pennsylvania requires one.

Radon mitigation: how it worksRadon mitigation costRadon mitigation systemsMitigators in Pennsylvania

Are radon levels high in Philadelphia County?

In 2020, 10.6% of the radon tests reported to CDC for Philadelphia County, Pennsylvania were at or above 4 pCi/L, and the median reported pre-mitigation result was 1.7 pCi/L. That is a share of reported tests, not of homes. EPA places Philadelphia County in Zone 3, lower predicted potential, a predicted average indoor screening level less than 2 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.

Radon levels: what a result meansWhat is radon?Radon levels in Pennsylvania

How do I get a radon test in Philadelphia County?

EPA says you can test your home yourself or hire a qualified radon test company, and that either approach takes only a small amount of time and effort. No radon testing business listed on Radon411 has an address in Philadelphia County or names it as a service area yet. The Pennsylvania radon program is the place to ask about certified testers and any test kit offer it runs.

Radon testing: how to test a homeRadon test kits comparedFree and low-cost kits by stateRadon Action Month checklistPennsylvania radon program

What EPA radon zone is Philadelphia County in?

EPA places Philadelphia County, Pennsylvania in Zone 3, which EPA describes as lower 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 Philadelphia County?

Yes. 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. EPA recommends considering a fix when the level is between 2 and 4 pCi/L. How to test a home.

When is the best time of year to test?

EPA says short-term tests stay in the home from 2 to 90 days and that all radon tests should run a minimum of 48 hours; long-term tests stay more than 90 days. EPA's guides do not name a best season: they say radon levels tend to vary from day to day and season to season, so a long-term test is more likely than a short-term test to tell you the year-round average.

What does it cost to test?

EPA's Citizen's Guide calls testing easy and inexpensive, and EPA's Home Buyer's and Seller's Guide says passive short-term and long-term devices are generally inexpensive, while active devices may cost more. No national average price is published for this, so Radon411 does not give one. What testing costs.

Which counties border Philadelphia County?

Philadelphia County borders 6 counties, derived from Census county geometry. Radon potential follows geology rather than county lines, so a bordering county's report can be relevant.

If you own, buy, sell or rent

What these figures mean for each reader, with the guide that covers it

The reported-test figures on this page describe Philadelphia County, Pennsylvania in 2020. They describe tests other people carried out in other buildings, and none of them measures yours.

Philadelphia County in figures

The figures above, said in words

What the published data says about Philadelphia County, in words. A zone and a share of tests describe an area, never the level in any one home.

    • Predicted

      Predicted

      EPA places Philadelphia County in Zone 3, lower predicted potential, the only one of Pennsylvania's 67 counties in that zone.

      Of the 6 bordering counties, EPA places Bucks County, Delaware County and Montgomery County in Zone 1 and Burlington County, NJ, Camden County, NJ and Gloucester County, NJ in Zone 2.

  • Reported tests

    Measured

    CDC has annual figures for Philadelphia County for 7 years, 2014 to 2020. In 2020, 10.6% of 8,442 reported tests were at or above 4 pCi/L.

    Across those years the share ranged from 9.6% (2018) to 13.6% (2014). Few tests in a year can move it a long way.

  • Local record

    Pennsylvania's radon program is the Radon Division, run by Department of Environmental Protection; its contacts are under Local resources.

    The county's largest incorporated place is Philadelphia; the figures here cover them as part of the county.

Products

Philadelphia County, Products

Testing and mitigation products

Whatever the figures for Philadelphia County show, only a test tells you about one home.

Test kits and monitors42

See all products

As an Amazon Associate, Radon411 earns from qualifying purchases.

Best radon monitors for Philadelphia County homes, compared

Testing

5

Mitigation

3

Explore

Philadelphia County, Bordering counties

Counties bordering Philadelphia County

Calculated by Radon411
Why bordering counties matter

6 counties share a boundary with Philadelphia County, computed from Census county geometry. Radon potential follows geology rather than county lines, so a bordering county’s report can be worth reading alongside this one.

Philadelphia County, Cities and towns

Cities and towns in Philadelphia County

The radon figures on this page are for Philadelphia County as a whole. They do not differ by city or town.

  • Philadelphia

One incorporated place, as listed in the U.S. Census Bureau’s 2020 place reference files.

Philadelphia County, Next steps

What to do next

  1. LearnKnow what radon isWhat radon is, how it gets indoors, and why a county zone is not a reading for your home.Learn about radon
  2. TestTest the building you live inShort-term or long-term, where the device goes, and closed-house conditions.How to test
  3. FixBring a high level downHow a mitigation system works, and the retest that confirms it.How mitigation works
  4. Find a proHire a certified professionalMeasurement and mitigation professionals by state, with their certifications.Find a professional

Informational. Follow EPA guidance. EPA says all radon tests should be taken for a minimum of 48 hours, with windows and doors closed from 12 hours before a short-term test.