Ohio · county radon data
Radon in Lorain County, Ohio
45.4% of the 2,937 home radon tests on record here reached the EPA action level — mid-pack for the state, ranked #60 of 88 tested Ohio counties.
What the numbers say
Lorain County sits 8.4 points below the Ohio median (53.8% of tests over the limit across the state's counties). The median reading among its 2,937 reported tests was 3.6 pCi/L — and the single highest test on record reached 76.9 pCi/L, more than 19× the action level. EPA maps place the county in Radon Zone 2 — moderate predicted potential (2–4 pCi/L average screening levels), which still produces plenty of homes over the limit.
Why: the ground under Lorain County
Covered by glacial till that ground up and redistributed Ohio's shale and carbonate bedrock. The till concentrates fine radioactive minerals while outwash sands provide fast pathways for soil gas — the reason most of Ohio is EPA Zone 1 or 2.
Geology sources: USGS WRI 98-4169 · EPA OH zone documentation.
The housing stock factor
The median Lorain County home dates to 1973 — decades before radon-resistant new construction entered building codes. With 317,129 residents largely housed in that older stock, testing is the only way any individual household knows where it stands.
ZIP codes in Lorain County
Ohio 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 |
|---|---|
| 44001 | Amherst |
| 44011 | Avon |
| 44012 | Avon Lake |
| 44028 | Columbia Station |
| 44035 | Elyria |
| 44039 | North Ridgeville |
| 44044 | Grafton |
| 44049 | Kipton |
| 44050 | Lagrange |
| 44052 | Lorain |
| 44053 | Lorain |
| 44054 | Sheffield Lake |
| 44055 | Lorain |
| 44074 | Oberlin |
| 44090 | Wellington |
Lorain County in the Ohio picture
| Lorain County | 45.4% over the limit | 2,937 tests |
| Ohio's highest: Pickaway County | 81.4% | 154 tests |
| Ohio county median | 53.8% | 88 counties ranked |
| Share of all Ohio tests from this county | 3.5% | |
Ranked nearby in Ohio
- Wyandot County — #57, 46.3% of 224 tests over the limit
- Hancock County — #58, 46.2% of 1,221 tests over the limit
- Wood County — #59, 45.5% of 1,469 tests over the limit
- Belmont County — #61, 45.2% of 723 tests over the limit
- Fulton County — #62, 45.2% of 56 tests over the limit
- Guernsey County — #63, 44.4% of 93 tests over the limit
(Ranking neighbors — counties adjacent in the Ohio test ranking, not necessarily on the map.)
High test? Fixes and real pricing: the Ohio mitigation cost guide. Every statistic here traces to the methodology (CDC EPHT (labs), 2008–2017; zones: EPA; year built & population: ACS 5-year).
Lorain County radon FAQ
- Is radon high in Lorain County?
- 45.4% of 2,937 home tests reported to the CDC came back at or above the EPA action level of 4 pCi/L — 8.4 points below the Ohio county median of 53.8%, ranking #60 of 88 tested counties. EPA classifies the county as Zone 2.
- Does an older home in Lorain County mean more radon risk?
- The county's median home was built in 1973 — 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 Lorain County numbers come from?
- 2,937 aggregated home tests in the CDC's Environmental Public Health Tracking dataset (CDC EPHT 2008-2017). Median reading: 3.6 pCi/L; the highest recorded test hit 76.9 pCi/L. How we handle the data, including its limits, is documented on our methodology page.
- What's the highest radon reading recorded in Lorain County?
- 76.9 pCi/L — 19× the EPA action level — against a county median of 3.6 pCi/L across 2,937 tests. That spread is the point: neighboring homes routinely test wildly differently.