Michigan · county radon data
Radon in Wayne County, Michigan
17.5% of the 4,582 home radon tests on record here reached the EPA action level — mid-pack for the state, ranked #38 of 83 tested Michigan counties.
What the numbers say
Wayne County sits 0.9 points above the Michigan median (16.6% of tests over the limit across the state's counties). The median reading among its 4,582 reported tests was 1.8 pCi/L — and the single highest test on record reached 50.7 pCi/L, more than 12× the action level. EPA maps place the county in Radon Zone 3 — lower predicted potential, though individual homes here still test high; zone maps predict averages, not addresses.
Why: the ground under Wayne County
Covered in thick glacial drift over the Michigan Basin's sedimentary rocks. Radon potential is moderate for most of the state, but tills incorporating shale or carbonate fragments can push individual homes well over the action level — testing is the only way to know. (Regional attribution here is well supported; unit-level detail is coarser — see methodology.)
Geology sources: USGS WRI 98-4169 · EPA MI zone documentation.
The housing stock factor
The median Wayne County home dates to 1956 — decades before radon-resistant new construction entered building codes. With 1,772,259 residents largely housed in that older stock, testing is the only way any individual household knows where it stands.
ZIP codes in Wayne County
Michigan doesn't publish ZIP-level test results, so these ZIPs share the county figures above — the roster is here so you can confirm your address is covered by this data.
| ZIP | Place |
|---|---|
| 48101 | Allen Park |
| 48111 | Belleville |
| 48120 | Dearborn |
| 48122 | Melvindale |
| 48124 | Dearborn |
| 48125 | Dearborn Heights |
| 48126 | Dearborn |
| 48127 | Dearborn Heights |
| 48128 | Dearborn |
| 48134 | Flat Rock |
| 48135 | Garden City |
| 48138 | Grosse Ile |
| 48141 | Inkster |
| 48146 | Lincoln Park |
| 48150 | Livonia |
| 48152 | Livonia |
| 48154 | Livonia |
| 48164 | New Boston |
| 48168 | Northville |
| 48170 | Plymouth |
| 48173 | Rockwood |
| 48174 | Romulus |
| 48180 | Taylor |
| 48183 | Trenton |
| 48184 | Wayne |
| 48185 | Westland |
| 48186 | Westland |
| 48187 | Canton |
| 48188 | Canton |
| 48192 | Wyandotte |
| 48193 | Riverview |
| 48195 | Southgate |
| 48201 | Detroit |
| 48202 | Detroit |
| 48203 | Highland Park |
| 48204 | Detroit |
| 48205 | Detroit |
| 48206 | Detroit |
| 48207 | Detroit |
| 48208 | Detroit |
| 48209 | Detroit |
| 48210 | Detroit |
| 48211 | Detroit |
| 48212 | Hamtramck |
| 48213 | Detroit |
| 48214 | Detroit |
| 48215 | Detroit |
| 48216 | Detroit |
| 48217 | Detroit |
| 48218 | River Rouge |
| 48219 | Detroit |
| 48221 | Detroit |
| 48223 | Detroit |
| 48224 | Detroit |
| 48225 | Harper Woods |
| 48226 | Detroit |
| 48227 | Detroit |
| 48228 | Detroit |
| 48229 | Ecorse |
| 48230 | Grosse Pointe |
+9 more — look yours up in the ZIP tool.
Wayne County in the Michigan picture
| Wayne County | 17.5% over the limit | 4,582 tests |
| Michigan's highest: Lenawee County | 56.7% | 1,349 tests |
| Michigan county median | 16.6% | 83 counties ranked |
| Share of all Michigan tests from this county | 5.6% | |
Ranked nearby in Michigan
- Oscoda County — #35, 18.5% of 40 tests over the limit
- Allegan County — #36, 18.4% of 592 tests over the limit
- Van Buren County — #37, 18% of 335 tests over the limit
- Saginaw County — #39, 17% of 2,213 tests over the limit
- Gratiot County — #40, 16.8% of 327 tests over the limit
- Ottawa County — #41, 16.8% of 1,957 tests over the limit
(Ranking neighbors — counties adjacent in the Michigan test ranking, not necessarily on the map.)
High test? Fixes and real pricing: the Michigan mitigation cost guide. Every statistic here traces to the methodology (CDC EPHT (labs), 2008–2017; zones: EPA; year built & population: ACS 5-year).
Wayne County radon FAQ
- Is radon high in Wayne County?
- 17.5% of 4,582 home tests reported to the CDC came back at or above the EPA action level of 4 pCi/L — 0.9 points above the Michigan county median of 16.6%, ranking #38 of 83 tested counties. EPA classifies the county as Zone 3.
- Does an older home in Wayne County mean more radon risk?
- The county's median home was built in 1956 — before radon-resistant construction practices entered building codes in the 1990s, so most of the housing stock has no built-in radon protection. Construction age changes the odds, not the answer: only a test tells you about your house.
- Where do these Wayne County numbers come from?
- 4,582 aggregated home tests in the CDC's Environmental Public Health Tracking dataset (CDC EPHT 2008-2017). Median reading: 1.8 pCi/L; the highest recorded test hit 50.7 pCi/L. How we handle the data, including its limits, is documented on our methodology page.
- What's the highest radon reading recorded in Wayne County?
- 50.7 pCi/L — 12× the EPA action level — against a county median of 1.8 pCi/L across 4,582 tests. That spread is the point: neighboring homes routinely test wildly differently.