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Radon in Ithaca, New York

EPA puts Tompkins County, where Ithaca is, in Zone 1, its highest radon zone, and only 18 radon tests from it are on file with CDC (2023). Homes with elevated levels occur in all three zones, so only a test measures yours.

Data checked By Radon411Methodology

How to test this homeFind a certified tester

  • Share at 4+ pCi/L

    28.0%

    3.5 pts above NY

    Tompkins
    28.0%
    New York
    24.5%

    Tompkins, 25th of 61 in NY, 2008 to 2017

  • Median result

    2.3pCi/L

    Below action level

    Tompkins
    2.3 pCi/L
    EPA
    4.0 pCi/L

    Midpoint of Tompkins's tests, 2008 to 2017

  • Nearest county

    38.6%

    Schuyler, 19 miles

    Schuyler
    38.6%
    Tompkins
    28.0%

    236 tests, 2008 to 2017

  • EPA radon zone

    Zone 1

    Highest potential

    1. Zone 1
    2. 2
    3. 3

    1 highest, 3 lowest

    Tompkins, where Ithaca is

  • Tests reported

    3,372

    In Tompkins

    Tompkins
    3,372
    Schuyler
    236

    Reported to CDC before any fix, 2008 to 2017

Read a result for Ithaca

Starts at Tompkins County's median, 2.3 pCi/L

2.3pCi/L

EPA’s own thresholds; the figures are the area’s, never this home’s.

EPA’s reading of 2.3 pCi/L

Between 2 and 4 pCi/L

  1. Under 20 to 1.9 pCi/L
  2. 2 to 4consider a fix
  3. 4 and aboveEPA says fix it

This result is between 2 and 4 pCi/L. EPA recommends considering a fix when the level is between 2 and 4 pCi/L. Tompkins County's median reported result, 2008 to 2017.

Interpret this readingWhat a fix costs

The data

Ithaca, What is published

What is published for Ithaca

Information:

Every figure for Ithaca is a county's

Radon data is published by county, not by city, so for Ithaca it is Tompkins County's: its EPA zone (Zone 1) and the 18 tests reported to CDC for 2023. Only a test tells you about one home.

Ithaca covers 5.4 square miles of land, all of it in Tompkins County. Its 33,632 residents live 6,241 to the square mile.

Ithaca, Counties

The county Ithaca lies in

Measured

Tompkins County's EPA zone and the figures CDC publishes for it, 2023.

Tompkins CountyZone 1Highest predicted potential

38.9%
Reported tests at or above 4 pCi/L
3.3 pCi/L
Median reported result
18 tests
Tests reported to CDC
10
Annual years on file

Tompkins County ranks 25th of 61 New York counties with 30 or more tests for that period, 14.4 points above the 24.5% pooled across New York's counties, 3.2 points above the national pool of 35.7%.

The counties nearest Ithaca with a CDC figure for 2008 to 2017, laboratory, measured from the middle of the city: Schuyler County (19 miles, 38.6% of 236 tests), Tioga County (21 miles, 38.9% of 1,419 tests) and Cortland County (24 miles, 51.0% of 788 tests). Across the 8 nearest, the share at or above 4 pCi/L runs from 21.3% to 52.3%; the farthest of them, Broome County, is 40 miles away at 24.9%.

The directory lists 1 business with an address in Ithaca, 1 for testing and 1 for mitigation. New York's other cities with a page of their own: Syracuse, Binghamton, Rochester and Buffalo.

The counties around Ithaca

By distance from the middle of Ithaca; counties with 30 or more tests.

Nearest counties to Ithaca with 30 or more tests
CountyDistanceTestsAt or above 4 pCi/LMedian
Schuyler County19 mi23638.6%2.5 pCi/L
Tioga County21 mi1,41938.9%2.7 pCi/L
Cortland County24 mi78851.0%4.1 pCi/L
Chemung County25 mi1,53752.3%4.3 pCi/L
Seneca County28 mi31921.3%2.0 pCi/L
Cayuga County33 mi72627.8%2.1 pCi/L
Yates County33 mi13545.9%3.5 pCi/L
Broome County40 mi5,89924.9%1.8 pCi/L

Predicted: EPA Map of Radon Zones, by county. Measured: CDC tracking data, by county, 2023.

Ithaca, Geology

The ground under Ithaca

Predicted

USGS's geologic map puts all of Ithaca's mapped land in one class: high radon potential. All of it lies in the area the map calls Allegheny Plateau, to which USGS gives a radon index of 12, in the high band (12 to 17).

USGS's geologic areas under Ithaca
AreaThe rock, in USGS's wordsPotentialRadon indexShare of land
Allegheny PlateauShale, limestone, and sandstone.High12100%

Names, descriptions and indexes: U.S. Geological Survey, Geologic Radon Potential Map (2025). Shares: Radon411, from the map cut to the boundary.

Ithaca beside its county and New York

All of Ithaca, like all of Tompkins County, is rated high. Ithaca has more high-potential ground than New York as a whole: 100% of its land against 48.9%.

Share of land by USGS radon potential: Ithaca, the county it lies in and New York
AreaEPA zoneLow potentialModerate potentialHigh potential
IthacaBy countyNoneNone100%
Tompkins CountyZone 1NoneNone100%
New York62 counties, pooled by land areaVaries22.0%28.2%48.9%

The map rates the ground, not the air in any home.

Ithaca, Homes

Homes in Ithaca

Ithaca has 15,607 homes, and many share a building: 43% are in buildings of five or more, 29% are detached houses, against 49% across Tompkins County. The homes are older than Tompkins County's as a whole: half were built before 1959 (1974 for Tompkins County), and 51% date from before 1960. Most occupied homes here are rented: owners live in 29% (Tompkins County: 54%). A tenant can run a test; a fix is the landlord's to make.

Homes in Ithaca, Tompkins County, New York, 2019 to 2023
HomesIthacaTompkins CountyNew York
Housing units15,60747,3628,539,536
Detached houses29%49%41%
In buildings of 5 or more43%24%34%
Mobile homes1%8%2%
Built before 196051%36%53%
Built since 200015%17%12%
Middle year built195919741958
Owner-occupied29%54%54%

Census Bureau, American Community Survey, 2019 to 2023: estimates from a sample of homes, looser for a small place. Shares by Radon411.

Local help

Ithaca, Professionals

Radon professionals listed in Ithaca

Businesses whose listed city is Ithaca, from the state registries and listings in the Radon411 directory, with the same business and certification status the directory shows.

1 listing with Ithaca as the city. See radon mitigation and testing in Ithaca, or all radon professionals in New York.

Ithaca, Local resources

Local resources for Ithaca

Who to ask in New York: its radon program, test kits and professionals.

The program's own words on licensing are on the New York page.

What it means

Ithaca, Questions

Questions about radon in Ithaca

What radon zone is Ithaca in?

Ithaca takes its zone from Tompkins County, which EPA puts in Zone 1, the map's highest class: a predicted county average above 4 pCi/L.

What are radon levels in Ithaca?

Only 18 tests from Tompkins County are on file with CDC for 2023, 38.9% of them at or above 4 pCi/L: too few to say how Ithaca runs.

Should I test my home in Ithaca?

Yes. With no dependable count of tests for Tompkins County, a test of your own is the only reading there is; a short-term kit takes a few days. How to test a home.

What ground is Ithaca built on, as far as radon goes?

USGS's geologic map puts all of Ithaca on one named area, "Allegheny Plateau", rated high for radon potential, radon index 12.

Is radon higher in the counties around Ithaca?

Some are and some are not. Against Tompkins County's 38.9%, 4 of the 8 nearest counties with a figure report more and 4 less, from Seneca County (21.3%, 28 miles off) to Chemung County (52.3%, 25 miles off).

Who tests for or fixes radon in Ithaca?

Radon411's directory has one business with an address in Ithaca, listed for both testing and mitigation. Every entry names the public list it was taken from. Radon professionals in Ithaca.

The answers use the published figures of Tompkins County, the county Ithaca lies in.

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