Radon in New York: County Zones and How to Test

EPA assigns radon zones to counties, not to whole states. On the EPA Map of Radon Zones, drawn in 1993 and not revised since, New York's 62 counties split 34 in Zone 1 (highest potential), 13 in Zone 2 (moderate) and 15 in Zone 3 (low). The zones describe predicted county averages, and EPA's own instruction is: "The map should not be used to determine if a home in a given zone should be tested for radon. Homes with elevated levels of radon have been found in all three zones. All homes should be tested for radon."

New York has 34 Zone 1 counties on the 1993 EPA map: Albany County, Allegany County, Broome County, Cattaraugus County, Cayuga County, Chautauqua County, Chemung County, Chenango County, Columbia County, Cortland County, Delaware County, Dutchess County and more, all listed on this page. Zone 1 means EPA predicted a county average indoor screening level above 4 pCi/L; it is not a reading of any home.

No, and that answer is EPA's own. The map predicts county averages from 1993 data; it does not measure homes. EPA's words: "The map should not be used to determine if a home in a given zone should be tested for radon. Homes with elevated levels of radon have been found in all three zones. All homes should be tested for radon." A short-term test costs little and is the only way to know your own number.

EPA's numbers, quoted directly: "The EPA recommends homes be fixed if the radon level is 4 pCi/L (picocuries per liter) (150 becquerels per meter cubed (Bq/m3)) or more. Because there is no known safe level of exposure to radon, the EPA also recommends that Americans consider fixing their home for radon levels between 2 pCi/L and 4 pCi/L (75 - 150 Bq/m3)." This site adds no threshold of its own.

January is National Radon Action Month on EPA's calendar, and winter is the practical testing season everywhere, because short-term tests want closed-house conditions. EPA's test instructions: "Follow the instructions that come with your test kit. If you are doing a short-term test, close your windows and outside doors and keep them closed as much as possible during the test." Cold months are when windows and doors stay shut anyway, in New York as anywhere.

Here is EPA's answer, verbatim: "Radon is the number one cause of lung cancer among non-smokers, according to EPA estimates. Overall, radon is the second leading cause of lung cancer. Radon is responsible for about 21,000 lung cancer deaths every year. About 2,900 of these deaths occur among people who have never smoked." The EPA and the U.S. Surgeon General recommend testing every home. Read more at https://www.epa.gov/radon/health-risk-radon, and talk to your doctor about personal risk, particularly if you smoke.

Yes. The New York State Department of Health publishes per-county results from its own test kit program, cumulative since 1987 and last updated 2025-11-18: homes tested, average pCi/L and counts at or above 4.0, for basement and first floor placements separately. This page shows those numbers next to each county's 1993 zone.