Radon in Montgomery County, Ohio

More than half of homes tested here were at or above the EPA action level.

2,223 home tests, 2008–2017, CDC lab data
  • Below 2 pCi/L: 23%
  • 2 to 4 pCi/L: 26%
  • 4 pCi/L or more: 50%
The line marks the EPA action level, 4 pCi/L.
Median level
4.0 pCi/L
EPA radon zone
Zone 1
In Ohio
46th of 80

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 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

    Most homes are fixed with a sub-slab depressurization system: a pipe and a quiet fan that pull radon from under the foundation and vent it above the roof. We're still collecting real installation prices for Ohio.

  3. Use a certified professional

    Look for a professional certified by the National Radon Proficiency Program (NRPP) or the National Radon Safety Board (NRSB), or by your state if it certifies radon contractors.

How Montgomery 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
Miami County65%
Darke County64%
Preble County63%
Greene County59%
Clark County58%
Butler County54%
Warren County53%
Ohio52%
Montgomery County50%
United States36%

Sources

Last updated October 2026. How we calculate these numbers.