Is radon high in Tompkins County, New York?

Low. The model predicts a long-term basement average of 2.0 pCi/L in Tompkins County (close to the US average of 1.8 and about 1.5× the New York average of 1.4). That is below the EPA's 2 pCi/L "consider fixing" threshold, though individual homes still vary. Ranked 26 of 62 New York counties.

Should I test for radon in Tompkins County?

Yes, once. The EPA recommends testing every home regardless of area, and the model's ZIP-level predictions in Tompkins County already range from 1.8 to 2.6 pCi/L. A short-term kit costs little and settles the question for your house.

What does EPA Radon Zone 1 mean for Tompkins County?

Zone 1 - highest potential (predicted average > 4 pCi/L). The zone map dates from 1993 and classifies whole counties. The newer model's predicted average of 2.0 pCi/L does not line up with Zone 1, which is common - the EPA itself says high-radon homes exist in every zone. Neither replaces a test of your own home.

How much does radon mitigation cost in Tompkins County?

A standard active sub-slab depressurization system typically runs $800-$2,500 installed nationally; New York quotes vary with foundation type (slab, crawlspace, basement), home size and local labor. Get two or three bids from certified mitigators listed by your state radon program or the EPA's find-a-professional page.

Radon levels in Tompkins County, New York

LowEPA Zone 1

Predicted long-term basement average of 2.0 pCi/L (model estimate) across 9 ZIP codes - close to the US average of 1.8, about 1.5× the New York average of 1.4. Ranked #26 of 62 New York counties.

Test Tompkins County, NY once anyway - radon varies house to house

The predicted basement average here is 2.0 pCi/L, below the EPA's 2 pCi/L "consider fixing" threshold. That's good news for the area - but the EPA still recommends every home be tested, because foundation cracks, soil pockets and ventilation make one house very different from its neighbor. One inexpensive kit settles it.

Get a short-term test kit →Or track it with a continuous monitor

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Predicted (model estimate). The pCi/L figures on this page are long-term area averages from a peer-reviewed national model built on millions of real radon tests (2001-2021). They describe the typical home in this area - not your home, which can be several times higher or lower. The EPA radon zone is a separate, 1993 county-level classification. How the numbers work.

2.0 ± 0.08

pCi/L predicted basement mean (model SD)

1.3 ± 0.09

pCi/L predicted upstairs (above-ground) mean

1.8-2.6

range of ZIP-level basement predictions in the county

What this means for Tompkins

The typical Tompkins County home is predicted below 2 pCi/L, the lowest band. That is the best case an area can show - but it describes the average house, and the ZIP-level predictions within the county still span 1.8 to 2.6 pCi/L.

Note that the EPA classifies Tompkins County as Zone 1 while the newer model predicts 2.0 pCi/L. The zone map predates two decades of test data; where they disagree, we grade on the model but show both. County figures weight each ZIP by its 2010 Census population, so they describe where people live rather than empty land.

Comparable New York counties: Washington County (2.0), Orange County (2.0), Oneida County (1.9), Ontario County (2.0). The state's highest is Schuyler County at 2.8 pCi/L.

ZIP codes in Tompkins County

Predicted basement and upstairs means by ZIP (model estimate). ZIPs whose land is mostly in this county.

ZIP	Basement	Upstairs	Grade
14850	1.8 ± 0.06	1.1	Low
14886	2.6 ± 0.16	1.7	Moderate
13073	2.3 ± 0.07	1.5	Moderate
14867	2.1 ± 0.07	1.4	Moderate
13068	2.3 ± 0.11	1.7	Moderate
13053	2.4 ± 0.10	1.6	Moderate
14882	2.4 ± 0.09	1.6	Moderate
14817	2.5 ± 0.06	1.6	Moderate
14881	2.1 ± 0.07	1.3	Moderate

If your test comes back at 4 pCi/L or higher

Mitigation is a routine job: a fan-driven pipe that vents soil gas from under the slab to above the roofline, typically $800-$2,500 installed (typical range; local quotes vary). Use certified professionals: EPA find-a-professional. Read the full mitigation guide.

Tompkins County radon questions

Is radon high in Tompkins County, New York?: Low. The model predicts a long-term basement average of 2.0 pCi/L in Tompkins County (close to the US average of 1.8 and about 1.5× the New York average of 1.4). That is below the EPA's 2 pCi/L "consider fixing" threshold, though individual homes still vary. Ranked 26 of 62 New York counties.
Should I test for radon in Tompkins County?: Yes, once. The EPA recommends testing every home regardless of area, and the model's ZIP-level predictions in Tompkins County already range from 1.8 to 2.6 pCi/L. A short-term kit costs little and settles the question for your house.
What does EPA Radon Zone 1 mean for Tompkins County?: Zone 1 - highest potential (predicted average > 4 pCi/L). The zone map dates from 1993 and classifies whole counties. The newer model's predicted average of 2.0 pCi/L does not line up with Zone 1, which is common - the EPA itself says high-radon homes exist in every zone. Neither replaces a test of your own home.
How much does radon mitigation cost in Tompkins County?: A standard active sub-slab depressurization system typically runs $800-$2,500 installed nationally; New York quotes vary with foundation type (slab, crawlspace, basement), home size and local labor. Get two or three bids from certified mitigators listed by your state radon program or the EPA's find-a-professional page.

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