Short-term kitKidde
442020 short-term charcoal radon test kit
- Lab fee included
Method: Charcoal
In home: 3 days
Locations and reports
Radon Levels in Chelan County, Washington
EPA puts Chelan County in Zone 3, its lowest radon zone, and only 20 radon tests from it are on file with CDC (2020). Homes with elevated levels occur in all three zones, so only a test measures yours.
Data checked By Radon411Methodology
Share at 4+ pCi/L
14.6%
10.9 pts below WA
- Chelan
- 14.6%
- Washington
- 25.5%
48 tests, 2008 to 2017
Median result
1.8pCi/L
Below action level
- Chelan
- 1.8 pCi/L
- EPA
- 4.0 pCi/L
Midpoint of the tests, 2008 to 2017
Tests reported
48
16th of 19 by tests
- Chelan
- 48
- Spokane
- 3,125
Reported to CDC before any fix, 2008 to 2017
EPA radon zone
Zone 3
Lower potential
- 1
- 2
- Zone 3
1 highest, 3 lowest
EPA predicts under 2 pCi/L indoors
Rank in Washington
10 of 19
Middle half
- Chelan
- 14.6%
- Pend Oreille
- 63.2%
By share, of 19 with 30+ tests
Read a result for Chelan County
Starts at Chelan County's median, 1.8 pCi/L
EPA’s own thresholds; the figures are the area’s, never this home’s.
EPA’s reading of 1.8 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. Chelan County's median reported result, 2008 to 2017.
The data
Chelan County, At a glance
Chelan County at a glance
Predicted: EPA radon zone
EPA Zone 3: lower predicted potential
USGS geologic potential: Low across 96% of the county's area
Predicted: EPA Map of Radon Zones
Measured: tests reported to CDC
Radon tests reported for Chelan County, 2020
| Year | Share of reported tests at or above 4 pCi/L |
|---|---|
| 2014 | 17.4% |
| 2015 | 38.5% |
| 2016 | 0.0% |
| 2017 | 20.7% |
| 2018 | 0.0% |
| 2019 | 35.3% |
| 2020 | 15.0% |
2020: 15.0%. Across these years the share ran from 0.0% to 38.5%. Each column counts radon tests reported to CDC that year, not homes.
What these figures count
Only 20 tests were reported to CDC for Chelan County over 2020, 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: 2020. Measured data period: 2005 to 2020 (every CDC figure on file).
Chelan County, Compared
Chelan County radon figures, compared
Calculated by Radon411Chelan County reports fewer high tests than Washington overall. 14.6% of its 48 tests over the 2008 to 2017 laboratory totals were at or above 4 pCi/L. That is 10.9 points below the 25.5% pooled from 39 Washington counties.
The newest figure, in 2020, counts only 20 tests (15.0% at or above 4 pCi/L), too few to compare, so this reading uses the 48-test figure.
Ordered from highest share down, it comes 10th of 19 Washington counties with 30 or more tests for the same period. Nationally, every county with a figure for the same period pools to 35.7%; Chelan County sits 21.1 points below it.
Next door, the shares run from 2.3% in Snohomish County to 35.0% in Okanogan County, with Skagit County, King County and Snohomish County below Chelan County. Zone 3 on EPA's map (predicted average under 2 pCi/L) and a 14.6% share point the same way here.
Half the tests came in under 1.8 pCi/L and half over it; the single highest reached 68.4 pCi/L. The rest split 56.3% under 2 pCi/L and 29.2% from 2 to 4 (Washington: 56.7% and 17.8%).
The busiest year on file was 2017, with 29 tests reported; the quietest, 2018, had 5.
Pooled shares: Radon411's sum of CDC's county counts for one period.
Chelan County, Geology
The ground under Chelan County
PredictedMost of the ground under Chelan County is one class on USGS's geologic map: 96.5% of its land is low radon potential, with 3.5% moderate. 96.5% of it lies in the area the map calls Cascade Mountains, to which USGS gives a radon index of 6, in the low band (5 to 8).
| Area | The rock, in USGS's words | Potential | Radon index | Share of land |
|---|---|---|---|---|
| Cascade Mountains | Northern Cascade Mountains are Mesozoic metamorphic rocks intruded by Mesozoic and Tertiary granitic rocks. Southern Cascade Mountains are composed primarily of Tertiary and Holocene volcanic rocks. | Low | 6 | 96.5% |
| Columbia Basin | Basaltic rocks low in uranium content. Uranium content of soils is moderately elevated. | Moderate | 10 | 3.5% |
Names, descriptions and indexes: U.S. Geological Survey, Geologic Radon Potential Map (2025). Shares: Radon411, from the map cut to the boundary.
Chelan County beside the ground around it
Across Washington 13.7% of the land is rated high; none of Chelan County's is. Of the 6 counties that border it, 2 have more high-potential ground, Okanogan County the most at 38.7%.
The map rates the ground, not the air in any home.
Local help
Chelan County, Local resources
Radon testing and mitigation in Chelan County
- Radon ProgramRadon Program, run by Washington State Department of Health, offers free or discounted test kits, and answers questions about testing and mitigation in Washington.Visit the program’s page(opens in a new tab)
- Free and low-cost kitsThe program says:
We have a limited supply of free radon test kits.
- Compare kits
- See the Washington directoryNo professionals are listed in Washington yet. The state program can point you to registered testers and mitigators.
What Washington's program says
- Phone
- 360-236-3200
- doh.radon@doh.wa.gov
What it means
Chelan County, Questions
Questions about radon in Chelan County
Are radon levels high in Chelan County?
In 2020, 15.0% of the radon tests reported to CDC for Chelan County, Washington were at or above 4 pCi/L, and the median reported pre-mitigation result was 1.7 pCi/L. Of 19 Washington counties with 30 or more tests for the same period, 9 reported a higher share; pooled, the state comes to 25.5%.
Which counties border Chelan County?
Chelan County borders 6 counties: Douglas County, Kittitas County, Okanogan County, Snohomish County, Skagit County and King County.
Products
Chelan County, Products
Testing a home in Chelan County
In Chelan County, 14.6% of 48 tests reported to CDC over the 2008 to 2017 laboratory totals reached 4 pCi/L, against 25.5% pooled across Washington. 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 Chelan 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
MonitorAEGTEST
HOUND-1085 palm-sized rechargeable radon detector
- C-NRPP 2024/25: Not included
- Battery
- Alarm
- Screen
Method: Semiconductor sensor
First reading: Within 6 hours
- See every kit and monitor Test kits and monitors
Test kits and monitors: 1 of 3
Explore
Chelan County, Bordering counties
Counties bordering Chelan County
Calculated by Radon411- Radon levels in Douglas CountyEPA zone 2
35.7%at or above 4 pCi/L
Median 2.3 pCi/L · 14 tests · 21.1 points above Chelan County
- Radon levels in Okanogan CountyEPA zone 1
35.0%at or above 4 pCi/L
Median 2.3 pCi/L · 40 tests · 20.4 points above Chelan County
- Radon levels in Kittitas CountyEPA zone 2
25.0%at or above 4 pCi/L
Median 1.4 pCi/L · 8 tests · 10.4 points above Chelan County
- Radon levels in Skagit CountyEPA zone 3
2.8%at or above 4 pCi/L
Median 0.8 pCi/L · 36 tests · 11.8 points below Chelan County
- Radon levels in King CountyEPA zone 3
2.6%at or above 4 pCi/L
Median 0.7 pCi/L · 1,267 tests · 12.0 points below Chelan County
- Radon levels in Snohomish CountyEPA zone 3
2.3%at or above 4 pCi/L
Median 0.5 pCi/L · 265 tests · 12.3 points below Chelan County
Chelan County, Cities and towns
Cities and towns in Chelan County
The Census Bureau estimates 81,941 residents in Chelan County for July 1, 2025, 2,639 more than in 2020 (+3.3%). That works out to 28 people per square mile of land. Its largest town, Wenatchee, has 35,547 residents, 43.4% of the total. Together its 5 incorporated places hold 59.0% of those residents; the other 41.0% live outside any of them. Reported testing is thin here: 48 tests over 2008 to 2017, or 0.6 for every 1,000 residents (2025 estimate), where Washington as a whole comes to 1.0.
From Wenatchee to Entiat, CDC publishes no figure by town: each reads Chelan County's.
| Place | Residents | Since 2020 | Share of residents |
|---|---|---|---|
| Wenatchee | 35,547 | −0.2% | 43.4% |
| Chelan | 4,494 | +6.0% | 5.5% |
| Leavenworth | 3,373 | +43.0% | 4.1% |
| Cashmere | 3,326 | +2.7% | 4.1% |
| Entiat | 1,576 | +18.3% | 1.9% |
5 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).
Chelan County, Homes
Homes in Chelan County
Of Chelan County's 38,129 homes, 68% are detached houses, against 62% across Washington; 12% are in buildings of five or more homes. Half of its homes were built before 1982, close to Washington's 1984: 28% date from before 1960 and 26% from 2000 or later. 63% of occupied homes are lived in by their owner (Washington: 64%); in the rest a tenant can run a test, but a fix is the landlord's to make.
| Homes | Chelan County | Washington |
|---|---|---|
| Housing units | 38,129 | 3,262,667 |
| Detached houses | 68% | 62% |
| In buildings of 5 or more | 12% | 22% |
| Mobile homes | 10% | 6% |
| Built before 1960 | 28% | 21% |
| Built since 2000 | 26% | 28% |
| Middle year built | 1982 | 1984 |
| Owner-occupied | 63% | 64% |
Census Bureau, American Community Survey, 2019 to 2023: estimates from a sample of homes, looser for a small place. Shares by Radon411.