Short-term kitempowerDX
Standard Radon Test short-term mail-in radon test kit
- Lab fee included
Method: Passive sampler
In home: 48 to 96 hours
Locations and reports
Radon Levels in Suffolk County, New York
EPA puts Suffolk County in Zone 3, its lowest radon zone, and only 6 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
Share at 4+ pCi/L
7.7%
17.5 pts below NY
- Suffolk
- 7.7%
- New York
- 25.2%
586 tests, 2006 to 2015
Median result
1.1pCi/L
Below action level
- Suffolk
- 1.1 pCi/L
- EPA
- 4.0 pCi/L
Midpoint of the tests, 2006 to 2015
Tests reported
586
36th of 61 by tests
- Suffolk
- 586
- Erie
- 11,939
Reported to CDC before any fix, 2006 to 2015
EPA radon zone
Zone 3
Lower potential
- 1
- 2
- Zone 3
1 highest, 3 lowest
EPA predicts under 2 pCi/L indoors
Rank in New York
56 of 61
Lowest quarter
- Suffolk
- 7.7%
- Chemung
- 52.6%
By share, of 61 with 30+ tests
Read a result for Suffolk County
Starts at Suffolk County's median, 1.1 pCi/L
EPA’s own thresholds; the figures are the area’s, never this home’s.
EPA’s reading of 1.1 pCi/L
Below 2 pCi/L
- Under 20 to 1.9 pCi/L
- 2 to 4consider a fix
- 4 and aboveEPA says fix it
This result is below 2 pCi/L, the level at which EPA says a fix should be considered. Suffolk County's median reported result, 2006 to 2015.
The data
Suffolk County, At a glance
Suffolk County at a glance
Predicted: EPA radon zone
EPA Zone 3: lower predicted potential
USGS geologic potential: Low across 79% of the county's area
Predicted: EPA Map of Radon Zones
Measured: tests reported to CDC
Radon tests reported for Suffolk County, 2023
| Year | Share of reported tests at or above 4 pCi/L |
|---|---|
| 2014 | 0.0% |
| 2015 | 0.0% |
| 2017 | 0.0% |
| 2018 | 0.0% |
| 2019 | 0.0% |
| 2020 | 0.0% |
| 2021 | 0.0% |
| 2022 | 0.0% |
| 2023 | 0.0% |
2023: 0.0%. Across these years the share ran from 0.0% to 0.0%. Each column counts radon tests reported to CDC that year, not homes.
What these figures count
Only 6 tests were reported to CDC for Suffolk County over 2023, and tests are often run on homes being sold or already suspected of a problem: so few describe neither the county nor this house.
Measured: CDC tracking data. Figure above: 2023. Measured data period: 2005 to 2023 (every CDC figure on file).
Suffolk County, Compared
Suffolk County radon figures, compared
Calculated by Radon411Suffolk County reports fewer high tests than New York overall. 7.7% of its 586 tests over the 2006 to 2015 laboratory totals were at or above 4 pCi/L. That is 17.5 points below the 25.2% pooled from 62 New York counties.
The newest figure, in 2023, counts only 6 tests (0.0% at or above 4 pCi/L), too few to compare, so this reading uses the 586-test figure.
Ordered from highest share down, it comes 56th of 61 New York counties with 30 or more tests for the same period. Nationally, every county with a figure for the same period pools to 36.3%; Suffolk County sits 28.6 points below it.
Nassau County, the one bordering county with a figure for the same period, reported 5.8%. Zone 3 on EPA's map (predicted average under 2 pCi/L) and a 7.7% share point the same way here.
Half the tests came in under 1.1 pCi/L and half over it; the single highest reached 14.5 pCi/L. The rest split 74.1% under 2 pCi/L and 18.3% from 2 to 4 (New York: 51.5% and 23.3%).
The busiest year on file was 2017, with 13 tests reported; the quietest, 2021, had 2.
Pooled shares: Radon411's sum of CDC's county counts for one period.
Suffolk County, State data
New York's own radon test data
MeasuredWhat New York's own agencies publish about radon tests in Suffolk County, with their period. These are not CDC's figures and are never added to them.
MeasuredState figures, not CDC's
What the New York State Department of Health reports for Suffolk County
Indoor air radon testing data (Environmental Public Health Tracker): short-term charcoal canister tests requested through the NYSDOH Radon Program, presented as five-year rolling averages. Period: 2015-2019. The publisher also lists 15 earlier periods.
Share at or above 4 pCi/L
0%
Average result
0.8 pCi/L
Tests behind these figures
5 tests a year on average
- Every figure is a five-year rolling average: the average result is the rolling average of each year's mean, and the test count is an average per year.
- The data only include tests requested through the NYSDOH Radon Program, and therefore may not capture all radon tests performed in a county.
- The data include both screening tests and post-mitigation tests, as it is not always possible to tell them apart.
- Radon testing by homeowners is optional in New York, so the values may not be representative of every home in the county.
- These figures describe tests reported to the New York State Department of Health in this area. They count a different set of tests than CDC's figures and are not a reading of any one home.
Measured: New York State Department of Health data, 2015-2019.
Suffolk County, Geology
The ground under Suffolk County
PredictedUSGS's geologic map puts all of Suffolk County's mapped land in one class: low radon potential. 79.0% of it lies in the area the map calls Atlantic Coastal Plain, to which USGS gives a radon index of 7, in the low band (5 to 8).
| Area | The rock, in USGS's words | Potential | Radon index | Share of land |
|---|---|---|---|---|
| Atlantic Coastal Plain | Glacial deposits and marine sediments. | Low | 7 | 79.0% |
Names, descriptions and indexes: U.S. Geological Survey, Geologic Radon Potential Map (2025). Shares: Radon411, from the map cut to the boundary.
Suffolk County beside the ground around it
Across New York 48.9% of the land is rated high; none of Suffolk County's is. None of the one county that borders it has any moderate-potential ground either.
The map rates the ground, not the air in any home.
Local help
Suffolk County, Local resources
Radon testing and mitigation in Suffolk County
- Radon ProgramRadon Program, run by New York State Department of Health, does not license radon professionals and offers free or discounted test kits, and answers questions about testing and mitigation in New York.Visit the program’s page(opens in a new tab)
- Free and low-cost kitsThe program says:
Providing patients with information about how low-cost test kits may be obtained from the Radon Program.
- Compare kits
- Professionals in New York88 professionals are listed in New York.
What New York's program says
- Phone
- 518-402-7556
- radon@health.ny.gov
- Licensing of radon professionals
NYS does not certify or license radon testers.
What it means
Suffolk County, Questions
Questions about radon in Suffolk County
Are radon levels high in Suffolk County?
In 2023, 0.0% of the radon tests reported to CDC for Suffolk County, New York were at or above 4 pCi/L, and the median reported pre-mitigation result was 0.6 pCi/L. Of 61 New York counties with 30 or more tests for the same period, 55 reported a higher share; pooled, the state comes to 25.2%.
Which counties border Suffolk County?
Suffolk County borders 1 county: Nassau County.
Products
Suffolk County, Products
Testing a home in Suffolk County
In Suffolk County, 7.7% of 586 tests reported to CDC over the 2006 to 2015 laboratory totals reached 4 pCi/L, against 25.2% pooled across New York. Zone 3 is the lowest label, yet homes at or above 4 pCi/L occur in every zone: a short-term kit (2 to 90 days) is the quick first check in Suffolk County.
Test kits and monitors3
See every kit and monitor
Long-term kit
RL416 long-term radon test kit, lab fee included
- Lab fee included
Method: Alpha track
In home: 90 days to 12 months
MonitorKidde
Radon Detector (RAB) battery digital radon detector with an alarm
- C-NRPP 2024/25: Not included
- Battery
- Alarm
- Screen
Method: Semiconductor sensor
First reading: Within 12 hours
- See every kit and monitor Test kits and monitors
Test kits and monitors: 1 of 3
Explore
Suffolk County, Bordering counties
Counties bordering Suffolk County
Calculated by Radon411- Radon levels in Nassau CountyEPA zone 3
5.8%at or above 4 pCi/L
Median 1.0 pCi/L · 637 tests · 1.9 points below Suffolk County
Suffolk County, Cities and towns
Cities and towns in Suffolk County
The Census Bureau estimates 1,546,090 residents in Suffolk County for July 1, 2025, 24,126 more than in 2020 (+1.6%). Packed into its land, that is 1,697 people per square mile. No town dominates: Lindenhurst, the largest, has 27,258 residents, 1.8% of the total. Together its 32 incorporated places hold 8.4% of those residents; the other 91.6% live outside any of them. Reported testing is thin here: 586 tests over 2006 to 2015, or 0.4 for every 1,000 residents (2025 estimate), where New York as a whole comes to 4.3.
From Lindenhurst to Dering Harbor, CDC publishes no figure by town: each reads Suffolk County's.
| Place | Residents | Since 2020 | Share of residents |
|---|---|---|---|
| Lindenhurst | 27,258 | +0.6% | 1.8% |
| Patchogue | 12,486 | +1.0% | 0.8% |
| Babylon | 12,281 | +1.2% | 0.8% |
| Lake Grove | 11,168 | +1.4% | 0.7% |
| Amityville | 9,799 | +3.5% | 0.6% |
| Port Jefferson | 8,306 | +4.2% | 0.5% |
| Northport | 7,336 | +0.1% | 0.5% |
| Southampton | 4,730 | +4.3% | 0.3% |
| Islandia | 3,733 | +4.1% | 0.2% |
| Lloyd Harbor | 3,587 | +0.5% | 0.2% |
| Brightwaters | 3,208 | +0.5% | 0.2% |
| Sag Harbor | 2,841 | +3.4% | 0.2% |
- Greenport
- Westhampton Beach
- Bellport
- Village of the Branch
- Quogue
- Nissequogue
- East Hampton
- Head of the Harbor
- Huntington Bay
- North Haven
- Old Field
- Poquott
- Belle Terre
- Sagaponack
- Asharoken
- Shoreham
- Ocean Beach
- West Hampton Dunes
- Saltaire
- Dering Harbor
32 incorporated places, as listed in the U.S. Census Bureau’s 2020 place reference files. Residents: U.S. Census Bureau population estimates for July 1, 2025 (Vintage 2025).
Suffolk County, Homes
Homes in Suffolk County
Suffolk County is a place of houses on their own lots: 80% of its 579,790 homes are detached single-family houses, against 41% across New York. Much of Suffolk County is recent building: 12% of its homes have gone up since 2000 and the middle year built is 1970, against 1958 for New York. Owners live in 82% of the occupied homes (New York: 54%), so for most households a test and a fix are their own to order.
| Homes | Suffolk County | New York |
|---|---|---|
| Housing units | 579,790 | 8,539,536 |
| Detached houses | 80% | 41% |
| In buildings of 5 or more | 8% | 34% |
| Mobile homes | 1% | 2% |
| Built before 1960 | 31% | 53% |
| Built since 2000 | 12% | 12% |
| Middle year built | 1970 | 1958 |
| Owner-occupied | 82% | 54% |
Census Bureau, American Community Survey, 2019 to 2023: estimates from a sample of homes, looser for a small place. Shares by Radon411.