Skip to content
RADON411

Locations and reports

Radon in Salem, Oregon

Salem lies in 2 counties, in EPA Zone 3; 86.1% of it is in Marion County, where 16.0% of 194 reported tests (2023) were at or above 4 pCi/L. Homes with elevated levels occur in all three zones, so the only way to know your home's level is to test it.

Data checked By Radon411Methodology

How to test this homeFind a certified tester

  • Share at 4+ pCi/L

    16.0%

    2.9 pts below OR

    Marion
    16.0%
    Oregon
    18.9%

    Marion, 6th of 14 in OR, 2023

  • Median result

    1.4pCi/L

    Below action level

    Marion
    1.4 pCi/L
    EPA
    4.0 pCi/L

    Midpoint of Marion's tests, 2023

  • Highest county

    16.0%

    Marion

    Marion
    16.0%
    Polk
    10.1%

    2 counties, 2 with 30+ tests, 2023

  • EPA radon zone

    Zone 3

    Low potential

    1. 1
    2. 2
    3. Zone 3

    1 highest, 3 lowest

    Marion; Polk Zone 3

  • Tests reported

    194

    In Marion

    Marion
    194
    Polk
    79

    Reported to CDC before any fix, 2023

Read a result for Salem

Starts at Marion County's median, 1.4 pCi/L

1.4pCi/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

  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. Marion County's median reported result, 2023.

Interpret this reading

The data

Salem, What is published

What is published for Salem

Information:

Every figure for Salem is a county's

Radon data is published by county, not by city, and Salem reaches into 2 counties: Marion County and Polk County. Each has its own EPA zone and its own CDC test figures, set side by side below and each labelled with its county. Only a test tells you about one home.

Salem covers 48.8 square miles of land: 86.1% of it lies in Marion County and 13.9% in Polk County. About 181,779 people live there, 3,725 to the square mile.

Salem, Counties

Salem's counties, side by side

Measured

Each county's own EPA zone and its own published CDC figures for 2023, the newest period any of them has. A county without a figure for that period is shown without one, never with a figure from another year.

  • Marion County
    EPA zone
    Zone 3: Lower predicted potential
    At or above 4 pCi/L
    16.0%
    Median result
    1.4 pCi/L
    Tests reported
    194 tests
    Annual years on file
    10
  • Polk County
    EPA zone
    Zone 3: Lower predicted potential
    At or above 4 pCi/L
    10.1%
    Median result
    1.4 pCi/L
    Tests reported
    79 tests
    Annual years on file
    10
The counties Salem lies in, each with its own EPA zone and its own published CDC figures for 2023
CountyEPA zoneReported tests at or above 4 pCi/LMedian reported resultTests reportedAnnual years on file
Marion CountyZone 3: Lower predicted potential16.0%1.4 pCi/L194 tests10
Polk CountyZone 3: Lower predicted potential10.1%1.4 pCi/L79 tests10

Salem spans 2 counties, each with its own EPA zone and its own CDC figure: Marion County (Zone 3, 16.0% of 194 tests) and Polk County (Zone 3, 10.1% of 79 tests).

Marion County ranks 6th of 14 Oregon counties with 30 or more tests for that period, 2.9 points below the 18.9% pooled across Oregon's counties, 17.4 points below the national pool of 33.4%. Of the city's other county, Polk County reported 10.1%.

Measured from the middle of Salem, the nearest counties with a CDC figure for 2023 are Yamhill County (25 miles, 21.2% of 33 tests), Benton County (36 miles, 15.6% of 32 tests) and Linn County (38 miles, 4.9% of 41 tests). Across the 8 nearest, the share at or above 4 pCi/L runs from 4.9% to 27.8%; the farthest of them, Lane County, is 69 miles away at 15.5%.

The directory lists 2 businesses with an address in Salem, 2 for testing and 1 for mitigation. Oregon's other cities with a page of their own: Portland.

Against Oregon and its other counties

Radon test figures for the counties Salem lies in
CountyShare of SalemTestsAt or above 4 pCi/LMedianOregon, pooledRank in the stateEPA zone
Marion County86.1%19416.0%1.4 pCi/L18.9%6 of 14Zone 3
Polk County13.9%7910.1%1.4 pCi/L18.9%11 of 14Zone 3

Shares of tests people chose to run and report, by county (2023); the state's is its counties' counts added up, calculated by Radon411. Only a test measures a home.

The counties around Salem

By distance from the middle of Salem; counties with 30 or more tests.

Nearest counties to Salem with 30 or more tests
CountyDistanceTestsAt or above 4 pCi/LMedian
Yamhill County25 mi3321.2%1.6 pCi/L
Benton County36 mi3215.6%0.9 pCi/L
Linn County38 mi414.9%0.8 pCi/L
Clackamas County43 mi32115.9%1.6 pCi/L
Washington County44 mi39611.4%1.3 pCi/L
Lincoln County46 mi368.3%1.1 pCi/L
Multnomah County52 mi79227.8%2.0 pCi/L
Lane County69 mi5815.5%1.0 pCi/L

The median reported pre-mitigation result for 2023 was 1.4 pCi/L in Marion County and 1.4 pCi/L in Polk County.

Predicted: EPA Map of Radon Zones, by county. Measured: CDC tracking data, by county, 2023.

Salem, Geology

The ground under Salem

Predicted

USGS's geologic map puts all of Salem's mapped land in one class: moderate radon potential. All of it lies in the area the map calls Wilamette Valley, to which USGS gives a radon index of 9, in the moderate band (9 to 11).

USGS's geologic areas under Salem
AreaThe rock, in USGS's wordsPotentialRadon indexShare of land
Wilamette ValleyGravelly to clayey alluvium with moderately elevated uranium content.Moderate9100%

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

Salem beside its counties and Oregon

Salem sits on more moderate-potential ground than Marion County as a whole: 100% of the city against 41.4% of the county. Salem has more moderate-potential ground than Oregon as a whole: 100% of its land against 62.3%.

Share of land by USGS radon potential: Salem, the counties it lies in and Oregon
AreaEPA zoneLow potentialModerate potentialHigh potential
SalemBy countyNone100%None
Marion CountyZone 358.6%41.4%None
Polk CountyZone 371.9%28.1%None
Oregon36 counties, pooled by land areaVaries37.5%62.3%None

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

Salem, Homes

Homes in Salem

Of Salem's 69,993 homes, 59% are detached houses, against 63% across Marion County; 24% are in buildings of five or more homes. Half of its homes were built before 1980, close to Marion County's 1979: 22% date from before 1960 and 24% from 2000 or later. 56% of occupied homes are lived in by their owner (Marion County: 62%); in the rest a tenant can run a test, but a fix is the landlord's to make.

Homes in Salem, Marion County, Oregon, 2019 to 2023
HomesSalemMarion CountyOregon
Housing units69,993130,6001,838,631
Detached houses59%63%63%
In buildings of 5 or more24%18%17%
Mobile homes5%8%8%
Built before 196022%20%23%
Built since 200024%22%24%
Middle year built198019791980
Owner-occupied56%62%63%

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

Local help

Salem, Professionals

Radon professionals listed in Salem

Businesses whose listed city is Salem, from the state registries and listings in the Radon411 directory, with the same business and certification status the directory shows.

2 listings with Salem as the city. See radon mitigation and testing in Salem, or all radon professionals in Oregon.

Salem, Local resources

Local resources for Salem

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

The program's own words on licensing are on the Oregon page.

What it means

Salem, Questions

Questions about radon in Salem

What radon zone is Salem in?

Both counties Salem reaches into (Marion County and Polk County) are in Zone 3, the map's lowest class: a predicted county average under 2 pCi/L. EPA zones counties, not cities, so that is the zone for every part of Salem.

What are radon levels in Salem?

Most tests near Salem come back under EPA's action level, but not all: 16.0% of Marion County's 194 tests for 2023 were at or above 4 pCi/L. The median reported result was 1.4 pCi/L. Polk County reported 10.1% of 79 tests; the counties are kept apart.

Should I test my home in Salem?

Yes. In Marion County, about one reported test in 6 reached 4 pCi/L. That is below Oregon's pooled 18.9%, and still not a reason to skip it, and ranks Marion County 6th of the 14 Oregon counties with 30 or more tests. The number for one house comes only from testing it. How to test a home.

What ground is Salem built on, as far as radon goes?

USGS's geologic map puts all of Salem on one named area, "Wilamette Valley", rated moderate for radon potential, radon index 9.

Is radon higher in the counties around Salem?

It depends which way you go. 2 of the 8 nearest counties with a figure report a larger share than Marion County's 16.0% and 6 a smaller one: from Linn County (4.9%, 38 miles off) to Multnomah County (27.8%, 52 miles off).

Who tests for or fixes radon in Salem?

Salem is the address of 2 businesses in Radon411's directory, 2 listed for testing and 1 for mitigation. Each entry names the public list it came from. Radon professionals in Salem.

The answers use the published figures of Marion County and Polk County, the counties Salem lies in.

Explore