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 Litchfield County, Connecticut
EPA puts Litchfield County in Zone 2, its middle radon zone, and 33.8% of its 346 reported radon tests (2019) were at or above 4 pCi/L. Homes with elevated levels occur in all three zones, so only a test measures yours.
Data checked By Radon411Methodology
Share at 4+ pCi/L
33.8%
1.3 pts below CT
- Litchfield
- 33.8%
- CT
- 35.1%
346 tests, 2019
Median result
2.0pCi/L
Below action level
- Litchfield
- 2.0 pCi/L
- EPA
- 4.0 pCi/L
Midpoint of the tests, 2019
Tests reported
346
6th of 8 by tests
- Litchfield
- 346
- Fairfield
- 2,784
Reported to CDC before any fix, 2019
EPA radon zone
Zone 2
Moderate potential
- 1
- Zone 2
- 3
1 highest, 3 lowest
EPA predicts 2 to 4 pCi/L indoors
Rank in CT
5 of 8
Middle half
- Litchfield
- 33.8%
- New London
- 48.5%
By share, of 8 with 30+ tests
Read a result for Litchfield County
Starts at Litchfield County's median, 2.0 pCi/L
EPA’s own thresholds; the figures are the area’s, never this home’s.
EPA’s reading of 2.0 pCi/L
Between 2 and 4 pCi/L
- Under 20 to 1.9 pCi/L
- 2 to 4consider a fix
- 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. Litchfield County's median reported result, 2019.
The data
Litchfield County, At a glance
Litchfield County at a glance
Predicted: EPA radon zone
EPA Zone 2: moderate predicted potential
Litchfield County is a
USGS geologic potential: Moderate across 61% of the county's area
Predicted: EPA Map of Radon Zones
Measured: tests reported to CDC
Radon tests reported for Litchfield County, 2019
| Year | Share of reported tests at or above 4 pCi/L |
|---|---|
| 2014 | 49.8% |
| 2015 | 65.8% |
| 2016 | 44.3% |
| 2017 | 41.5% |
| 2018 | 24.6% |
| 2019 | 33.8% |
2019: 33.8%. Across these years the share ran from 24.6% to 65.8%. Each column counts radon tests reported to CDC that year, not homes.
What these figures count
These are the 346 tests reported to CDC for Litchfield County over 2019, many from homes being sold or already suspected of a problem: they describe the county's reported tests, not this house.
Measured: CDC tracking data. Figure above: 2019. Measured data period: 2005 to 2019 (every CDC figure on file).
Litchfield County, Compared
Litchfield County radon figures, compared
Calculated by Radon411In Litchfield County, about 3 in 10 reported tests in 2019 (117 of 346) were at or above EPA's action level. Against the national pool of 29.0%, the gap is 4.8 points higher. Across 8 Connecticut counties pooled together, 35.1% of tests reached that level, so Litchfield County runs 1.3 points below its state.
Of 4 neighbours with a figure, 2 reported a larger share at or above 4 pCi/L and 2 a smaller one; the spread is 31.5% (Hartford County) to 37.9% (New Haven County). By share, Litchfield County is 5th of 8 Connecticut counties with 30 or more tests for the same period.
Year by year, 2014 opened at 49.8% and 2019 closed at 33.8% (down 16.0 points), with 2015 the high at 65.8%. Half the tests came in under 2.0 pCi/L and half over it; the single highest reached 30.0 pCi/L. Below the action level, 160 tests (46.2%) came in under 2 pCi/L, against 47.9% statewide, and 69 tests (19.9%) fell between 2 and 4, against 17.0% statewide.
Zone 2 on EPA's map (predicted average between 2 and 4 pCi/L) and a 33.8% share point the same way here. USGS geology rates 61% of the county's land moderate radon potential.
The busiest year on file was 2015, with 377 tests reported; the quietest, 2014, had 235.
Litchfield CountyConnecticut, pooled
| Year | Tests | Litchfield County, at or above 4 pCi/L | Connecticut, pooled |
|---|---|---|---|
| 2014 | 235 | 49.8% | 53.1% |
| 2015 | 377 | 65.8% | 63.4% |
| 2016 | 336 | 44.3% | 45.1% |
| 2017 | 284 | 41.5% | 38.3% |
| 2018 | 260 | 24.6% | 31.0% |
| 2019 | 346 | 33.8% | 35.1% |
Pooled shares: Radon411's sum of CDC's county counts for one period.
Litchfield County, Geology
The ground under Litchfield County
PredictedUSGS's geologic map splits Litchfield County: 60.8% of its land is moderate radon potential and 38.6% high and 0.6% low. The map puts 38.6% of Litchfield County in the area it calls Connecticut Valley Synclinorium and 23.5% in Proterozoic massifs, with 3 smaller areas beside them. USGS gives the first a radon index of 12, in the high band (12 to 17), and the second 10, in the moderate band (9 to 11).
| Area | The rock, in USGS's words | Potential | Radon index | Share of land |
|---|---|---|---|---|
| Connecticut Valley Synclinorium | Schist, gneiss and phyllite. | High | 12 | 38.6% |
| Proterozoic massifs | Gneiss, granitic gneiss, amphibolite, mica schist. | Moderate | 10 | 23.5% |
| Taconic Allochthons | Cambrian schist. | Moderate | 11 | 21.9% |
| Carbonate shelf | Marble and schist. | Moderate | 9 | 15.4% |
| Newark Terrane (Mesozoic Basins) | Sedimentary and igneous rocks including dolerite, arkose, basalt. | Low | 8 | 0.6% |
Names, descriptions and indexes: U.S. Geological Survey, Geologic Radon Potential Map (2025). Shares: Radon411, from the map cut to the boundary.
Litchfield County beside the ground around it
On high-potential ground Litchfield County is close to Connecticut as a whole: 38.6% of its land against 44.1%. Of the 6 counties that border it, 3 have more high-potential ground, Dutchess County, NY the most at 99.6%.
The map rates the ground, not the air in any home.
Local help
Litchfield County, Local resources
Radon testing and mitigation in Litchfield County
- Radon ProgramRadon Program, run by Department of Public Health, does not license radon professionals and offers free or discounted test kits, and answers questions about testing and mitigation in Connecticut.Visit the program’s page(opens in a new tab)
- Free and low-cost kitsThe program says:
A part of the partnership includes providing LHDs free short-term radon in air test kits for distribution to community residents.
- Compare kits
- Professionals in Connecticut71 professionals are listed in Connecticut.
What Connecticut's program says
- Phone
- (860) 509-7300
- DPH.RadonReports@ct.gov
- Licensing of radon professionals
The State of Connecticut does not license or otherwise certify radon professionals, however, the Radon Program maintains lists of nationally certified professionals in accordance with the requirements of CGS § 19a-14b (5)(b).
What it means
Litchfield County, Questions
Questions about radon in Litchfield County
Are radon levels high in Litchfield County?
In 2019, 33.8% of the radon tests reported to CDC for Litchfield County, Connecticut were at or above 4 pCi/L, and the median reported pre-mitigation result was 2.0 pCi/L. Of 8 Connecticut counties with 30 or more tests for the same period, 4 reported a higher share; pooled, the state comes to 35.1%.
Which counties border Litchfield County?
Litchfield County borders 6 counties: Dutchess County, NY, Hartford County, CT, Fairfield County, CT, New Haven County, CT, Hampden County, MA and Berkshire County, MA.
Products
Litchfield County, Products
Testing a home in Litchfield County
In Litchfield County, 33.8% of 346 tests reported to CDC in 2019 reached 4 pCi/L, against 35.1% pooled across Connecticut. In Zone 2 a short-term kit (2 to 90 days) is the quick first check in Litchfield County; a long-term test tells the year-round average.
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
Litchfield County, Bordering counties
Counties bordering Litchfield County
Calculated by Radon411- Radon levels in New Haven County, CTEPA zone 1
37.9%at or above 4 pCi/L
Median 2.2 pCi/L · 1,007 tests · 4.1 points above Litchfield County
- Radon levels in Dutchess County, NYEPA zone 1
36.8%at or above 4 pCi/L
Median 2.3 pCi/L · 38 tests · 3.0 points above Litchfield County
- Radon levels in Fairfield County, CTEPA zone 1
33.4%at or above 4 pCi/L
Median 2.1 pCi/L · 2,784 tests · 0.4 points below Litchfield County
- Radon levels in Hartford County, CTEPA zone 3
31.5%at or above 4 pCi/L
Median 1.4 pCi/L · 606 tests · 2.3 points below Litchfield County
- Radon levels in Hampden County, MAEPA zone 2
No CDC figure for 2019; its page reads it against its own neighbours.
- Radon levels in Berkshire County, MAEPA zone 2
No CDC figure for 2019; its page reads it against its own neighbours.
Litchfield County, Cities and towns
Cities and towns in Litchfield County
Torrington is its largest town, with 35,796 residents.
From Torrington to Bantam, CDC publishes no figure by town: each reads Litchfield County's.
| Place | Residents | Since 2020 | Share of residents |
|---|---|---|---|
| Torrington | 35,796 | +1.2% | Not published |
| Litchfield | 1,220 | +2.4% | Not published |
| Bantam | 772 | +2.5% | Not published |
3 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).