Radon in Westmoreland County, Pennsylvania

About 4 in 10 homes tested here were at or above the EPA action level.

28,830 home tests, 2016–2026, Pennsylvania DEP
  • Below 2 pCi/L: 32%
  • 2 to 4 pCi/L: 31%
  • 4 pCi/L or more: 36%
The line marks the EPA action level, 4 pCi/L.
Typical level
3.0 pCi/L
EPA radon zone
Zone 1
In Pennsylvania
46th of 67

EPA Zone 1, the highest radon potential (predicted average above 4 pCi/L). The EPA zone map dates from 1993 and is meant for planning; high levels are found in every zone.

What fixing radon costs in Westmoreland County

From 1,680 standard systems installed in the county since 2021, as reported to the state. Half of homeowners paid between the low and high figures.

What to do next

  1. Test your home

    Radon levels vary between neighboring houses, so area data can't tell you your own home's level. A short-term test takes 2 to 7 days in the lowest lived-in floor. A long-term test (90 days or more) gives a more reliable average.

  2. If your result is 4 pCi/L or more, fix it

    A certified professional installs a sub-slab system: a pipe and a quiet fan that pull radon from under the foundation and vent it above the roof. It usually takes a day; the costs are above.

    It works: across Pennsylvania, the typical level dropped from 7.7 to 1.0 pCi/L after mitigation, and 95% of homes ended up below the action level.

  3. Use a certified professional

    Pennsylvania requires radon testers and mitigators to be certified. The state publishes the list of certified mitigation firms by county.

How Westmoreland County compares

Share of homes tested at or above 4 pCi/L, with neighboring counties. Lab data 2008–2017, the only source that covers every state.

Share of homes tested at or above 4 pCi/L
Armstrong County58%
Indiana County52%
Butler County49%
Cambria County46%
Somerset County45%
Westmoreland County41%
Pennsylvania41%
Washington County38%
Allegheny County37%
United States36%
Fayette County36%

Radon by zip code in Westmoreland County

Home tests reported to the Pennsylvania DEP since October 2016, most-tested zip codes first.

Zip codeHomes testedTests4 or moreMedian
15601
5,75534%2.8 pCi/L
15642
3,62733%2.8 pCi/L
15068
2,56639%3.3 pCi/L
15650
2,18535%2.8 pCi/L
15668
2,00541%3.3 pCi/L
15644
1,62840%3.3 pCi/L
15658
1,14544%3.8 pCi/L
15632
1,06444%3.3 pCi/L
15613
92549%3.8 pCi/L
15012
80034%2.8 pCi/L
15666
76329%2.8 pCi/L
15085
71231%2.3 pCi/L
15656
69831%2.3 pCi/L
15626
46333%2.8 pCi/L
15627
42734%2.8 pCi/L
15636
40032%2.8 pCi/L
15062
36339%3.3 pCi/L
15683
33131%2.8 pCi/L
15690
32733%2.8 pCi/L
15089
29636%3.3 pCi/L
15672
26923%2.3 pCi/L
15697
18435%3.3 pCi/L
15670
14348%3.8 pCi/L
15610
13936%2.8 pCi/L
15665
12429%2.3 pCi/L
15944
12155%4.8 pCi/L
15639
11525%2.3 pCi/L
15637
9232%2.8 pCi/L
15692
7735%2.8 pCi/L
15687
7650%3.8 pCi/L
15679
7337%2.8 pCi/L
15655
7020%2.3 pCi/L
15618
6838%3.3 pCi/L
15677
6847%3.8 pCi/L
15479
6248%3.3 pCi/L
15623
5654%4.3 pCi/L
15671
5359%4.3 pCi/L
15083
5235%3.3 pCi/L
15923
5244%3.3 pCi/L
15675
4927%2.3 pCi/L
15678
3661%6.3 pCi/L
15676
3250%3.8 pCi/L
15661
3132%3.3 pCi/L
15620
2821%2.8 pCi/L
15663
2635%2.3 pCi/L
15641
2241%3.3 pCi/L
15688
2232%2.3 pCi/L
15628
2055%4.3 pCi/L
15611Too few tests16––
15634Too few tests15––
15684Too few tests12––
15698Too few tests12––
15779Too few tests12––
15615Too few tests9––
15616Too few tests9––
15617Too few tests9––
15619Too few tests9––
15624Too few tests9––
15646Too few tests9––
15629Too few tests8––
15612Too few tests6––
15625Too few tests6––
15696Too few tests6––
15635Too few tests4––
15647Too few tests4––
15660Too few tests4––
15662Too few tests4––
15691Too few tests4––
15072Too few tests3––
15087Too few tests3––
15633Too few tests3––
15638Too few tests3––
15693Too few tests3––
15664Too few tests2––
15680Too few tests2––
15013Too few tests1––
15640Too few tests1––
15645Too few tests1––
16012Too few tests1––

"–" means fewer than 20 tests, too few for a reliable figure.

Sources

Last updated October 2026. How we calculate these numbers.