28%tests ≥ 4 pCi/L
9,114tests on record
2.0median pCi/L
Zone 1EPA zone (1993 prediction)

Test results in Onondaga County

ResultShareEPA guidance
Below 2 pCi/L49%Below EPA's levels
2 to 4 pCi/L23%Consider fixing
4 pCi/L or more28%EPA recommends fixing

What the data shows

Where Onondaga County sits among New York's 62 counties with dataEach dot is a county's share of tests at or above 4 pCi/L · Radon test results from laboratories, 2008–2017
0%20%40%60%

How Onondaga County compares

Onondaga County ranks 3 of 5 among its neighboursShare of tests at or above 4 pCi/L · Radon test results from laboratories, 2008–2017 · whisker: 95% range
Cortland County51%Madison County35%Onondaga County28%Cayuga County28%Oswego County15%New York 25%
Data table
AreaTests ≥ 4 pCi/LTests
Cortland County51%788
Madison County35%979
Onondaga County28%9,114
Cayuga County28%726
Oswego County15%778
New York (62 counties)25%97,145

Same source as Onondaga County.

What it means for your home

About 1 in 4 results in Onondaga 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: 9,114. 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