Wisconsin radon levels by county

Wisconsin Radon Levels by County

Wisconsin has some of the highest indoor radon in the country — and it varies sharply by county. Below is the measured average for every Wisconsin county we serve (CDC test data, 2008–2017), compared to the U.S. average of 1.3 pCi/L and the EPA action level of 4.0. Find your county to see what's typical and what to do next.

County	Avg radon (pCi/L)	vs U.S.	Status
Marathon County →	11.6	8.9×	Above action level
Waukesha County →	6.4	4.9×	Above action level
Rock County →	6.4	4.9×	Above action level
Winnebago County →	6.2	4.8×	Above action level
Outagamie County →	6	4.6×	Above action level
Racine County →	5.8	4.5×	Above action level
Brown County →	5.5	4.2×	Above action level
Eau Claire County →	5.2	4×	Above action level
Milwaukee County →	4.8	3.7×	Above action level
Dane County →	4.8	3.7×	Above action level
Kenosha County →	4.7	3.6×	Above action level
Sheboygan County →	4.4	3.4×	Above action level
La Crosse County →	4.2	3.2×	Above action level

Source: CDC National Environmental Public Health Tracking Network — mean pre-mitigation radon level in tested buildings, Wisconsin, 2008–2017. Every home should be tested regardless of county average.

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