Radon in Northampton County, Pennsylvania

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

30,787 home tests, 2016–2026, Pennsylvania DEP
  • Below 2 pCi/L: 41%
  • 2 to 4 pCi/L: 20%
  • 4 pCi/L or more: 39%
The line marks the EPA action level, 4 pCi/L.
Typical level
2.8 pCi/L
EPA radon zone
Zone 1
In Pennsylvania
34th 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 Northampton County

From 1,278 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.

Already tested? Check your result

Unit
Type of test

Using a digital monitor? If it has run for 90 days or more, enter its long-term average and choose long-term.

How Northampton 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
Carbon County54%
Northampton County50%
Lehigh County49%
Monroe County45%
Pennsylvania41%
United States36%
Bucks County28%

Radon by zip code in Northampton County

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

Zip codeHomes testedTests4 or moreMedian
18017
5,94031%1.8 pCi/L
18015
3,63932%2.3 pCi/L
18045
3,11144%3.3 pCi/L
18042
3,10637%2.8 pCi/L
18064
2,89346%3.3 pCi/L
18040
2,44840%2.8 pCi/L
18020
2,13444%3.3 pCi/L
18067
1,47042%3.3 pCi/L
18055
1,20535%2.8 pCi/L
18013
1,19846%3.8 pCi/L
18014
1,04149%3.8 pCi/L
18072
67847%3.8 pCi/L
18088
62358%5.8 pCi/L
18091
55930%1.8 pCi/L
18343
35345%3.3 pCi/L
18038
24250%3.8 pCi/L
18085
5571%5.3 pCi/L
18035
2857%5.8 pCi/L
18063
2352%5.3 pCi/L
18083Too few tests19––
18351Too few tests17––
18086Too few tests4––
18024Too few tests1––

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

Sources

Last updated October 2026. How we calculate these numbers.