Radon in Mercer County, Pennsylvania

About 3 in 10 homes tested here were at or above the EPA action level.

4,644 home tests, 2016–2026, Pennsylvania DEP
  • Below 2 pCi/L: 39%
  • 2 to 4 pCi/L: 31%
  • 4 pCi/L or more: 30%
The line marks the EPA action level, 4 pCi/L.
Typical level
2.6 pCi/L
EPA radon zone
Zone 2
In Pennsylvania
53rd of 67

EPA Zone 2, moderate radon potential (predicted average 2 to 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 Mercer County

From 169 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 Mercer 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
Butler County49%
Venango County48%
Lawrence County43%
Pennsylvania41%
Mercer County37%
United States36%
Trumbull County, OH35%
Crawford County33%
Mahoning County, OH23%

Radon by zip code in Mercer County

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

Zip codeHomes testedTests4 or moreMedian
16148
1,06232%2.8 pCi/L
16127
95632%2.8 pCi/L
16125
69824%1.8 pCi/L
16137
62731%2.8 pCi/L
16146
38015%1.8 pCi/L
16150
27130%2.3 pCi/L
16159
14946%3.8 pCi/L
16121
10920%2.3 pCi/L
16145
8947%3.8 pCi/L
16154
8038%3.3 pCi/L
16153
6840%3.3 pCi/L
16133
4432%3.3 pCi/L
16130
3225%2.8 pCi/L
16161
2719%1.8 pCi/L
16114Too few tests19––
16124Too few tests16––
16113Too few tests9––
16311Too few tests5––
16151Too few tests2––
15150Too few tests1––

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

Sources

Last updated October 2026. How we calculate these numbers.