Test results in Jefferson County
| Result | Share | EPA guidance |
|---|---|---|
| Below 2 pCi/L | 60% | Below EPA's levels |
| 2 to 4 pCi/L | 24% | Consider fixing |
| 4 pCi/L or more | 16% | EPA recommends fixing |
What the data shows
- Higher share of high results than 18 of 62 New York counties.
- Below the New York rate of 25%.
- Higher than 2 of 4 neighbouring counties.
- 40% of results at or above 2 pCi/L.
- 19.5 tests per 1,000 homes (New York: 11.3).
- Median result 1.5 pCi/L: below 2 pCi/L.
How Jefferson County compares
Data table
| Area | Tests ≥ 4 pCi/L | Tests |
|---|---|---|
| Cayuga County | 28% | 726 |
| Lewis County | 20% | 109 |
| Jefferson County | 16% | 1,204 |
| Oswego County | 15% | 778 |
| St. Lawrence County | 13% | 151 |
| New York (62 counties) | 25% | 97,145 |
Same source as Jefferson County.
What it means for your home
About 1 in 6 results in Jefferson County were at or above 4 pCi/L, where the EPA recommends a fix. Only a test shows your own home's level.
Levels in pCi/L from the EPA. The WHO reference level is 100 Bq/m³, about 2.7 pCi/L.
Test your home
Start with a short-term test (2–90 days) and confirm a result of 4 pCi/L or more with a second test. EPA guide
Sponsored: we earn a commission on purchases through these links. We haven't tested Airthings monitors yet.
Prefer a digital monitor? See Airthings radon monitors, or enter code radonbycounty-10OFF at their discount store for 10% off.
Fixing high radon
No local job records yet. National range: $800–$2,500, average $1,200 (EPA, 2003). Cost guide →
New York doesn't license radon mitigators; look for NRPP or NRSB certification. Source
Buying or selling here
New York's Property Condition Disclosure Statement asks the seller whether a radon test has been done and, if so, for a copy of the report (Real Property Law § 462). Source
Checked against the official text on 2026-11-03. Not legal advice.
About this data
Source: Radon test results from laboratories (CDC Environmental Public Health Tracking Network). Period: 2008–2017. Tests: 1,204. Read the methodology →
These are voluntary and real-estate tests, not a random sample of homes, so they describe tested homes rather than every home.
About this page
Published by Ray Roman, editor of Radon by County. Figures are loaded from the cited source and spot-checked against it. Editorial policy · About us