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 DuPage County, Illinois
EPA puts DuPage County in Zone 2, its middle radon zone, and 33.7% of its 19,401 reported radon tests (2017) 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
33.7%
0.0 pts above IL
- DuPage
- 33.7%
- Illinois
- 33.7%
19,401 tests, 2017
Median result
2.7pCi/L
Below action level
- DuPage
- 2.7 pCi/L
- EPA
- 4.0 pCi/L
Midpoint of the tests, 2017
Tests reported
19,401
2nd of 70 by tests
- DuPage
- 19,401
- Cook
- 26,937
Reported to CDC before any fix, 2017
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 Illinois
53 of 70
Middle half
- DuPage
- 33.7%
- Stark
- 69.2%
By share, of 70 with 30+ tests
Read a result for DuPage County
Starts at DuPage County's median, 2.7 pCi/L
EPA’s own thresholds; the figures are the area’s, never this home’s.
EPA’s reading of 2.7 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. DuPage County's median reported result, 2017.
The data
DuPage County, At a glance
DuPage County at a glance
Predicted: EPA radon zone
EPA Zone 2: moderate predicted potential
DuPage County is a
USGS geologic potential: Moderate across 80% of the county's area
Predicted: EPA Map of Radon Zones
Measured: tests reported to CDC
Radon tests reported for DuPage County, 2017
| Year | Share of reported tests at or above 4 pCi/L |
|---|---|
| 2014 | 36.1% |
| 2015 | 36.6% |
| 2016 | 21.1% |
| 2017 | 33.7% |
2017: 33.7%. Across these years the share ran from 21.1% to 36.6%. Each column counts radon tests reported to CDC that year, not homes.
What these figures count
These are the 19,401 tests reported to CDC for DuPage County over 2017, 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: 2017. Measured data period: 2005 to 2017 (every CDC figure on file).
DuPage County, Compared
DuPage County radon figures, compared
Calculated by Radon411In DuPage County, about 3 in 10 reported tests in 2017 (6,534 of 19,401) were at or above EPA's action level. Against the national pool of 31.7%, the gap is 2.0 points higher. Pooled across 93 Illinois counties, the share is the same 33.7%.
Of 4 neighbours with a figure, 3 reported a larger share at or above 4 pCi/L and 1 a smaller one; the spread is 19.4% (Cook County) to 40.0% (Will County). By share, DuPage County is 53rd of 70 Illinois counties with 30 or more tests for the same period.
Year by year, 2014 opened at 36.1% and 2017 closed at 33.7% (down 2.4 points), with 2015 the high at 36.6%. Half the tests came in under 2.7 pCi/L and half over it; the single highest reached 94.6 pCi/L. Below the action level, 7,401 tests (38.1%) came in under 2 pCi/L, against 37.7% statewide, and 5,466 tests (28.2%) fell between 2 and 4, against 28.6% statewide.
Zone 2 on EPA's map (predicted average between 2 and 4 pCi/L) and a 33.7% share point the same way here. USGS geology rates 80% of the county's land moderate radon potential.
The busiest year on file was 2014, with 28,833 tests reported; the quietest, 2016, had 966.
DuPage CountyIllinois, pooled
| Year | Tests | DuPage County, at or above 4 pCi/L | Illinois, pooled |
|---|---|---|---|
| 2014 | 28,833 | 36.1% | 37.8% |
| 2015 | 17,028 | 36.6% | 36.6% |
| 2016 | 966 | 21.1% | 17.4% |
| 2017 | 19,401 | 33.7% | 33.7% |
Pooled shares: Radon411's sum of CDC's county counts for one period.
DuPage County, Geology
The ground under DuPage County
PredictedMost of the ground under DuPage County is one class on USGS's geologic map: 80.1% of its land is moderate radon potential, with 19.9% high. The map puts 80.1% of DuPage County in the area it calls Wheaton Morainal Country and 19.9% in Bloomington Ridged Plain. USGS gives the first a radon index of 11, in the moderate band (9 to 11), and the second 13, in the high band (12 to 17).
| Area | The rock, in USGS's words | Potential | Radon index | Share of land |
|---|---|---|---|---|
| Wheaton Morainal Country | Glacial lake deposits and clay-rich glacial till. | Moderate | 11 | 80.1% |
| Bloomington Ridged Plain | Wisconsinan glacial deposits and loess over Paleozoic sedimentary rocks. | High | 13 | 19.9% |
Names, descriptions and indexes: U.S. Geological Survey, Geologic Radon Potential Map (2025). Shares: Radon411, from the map cut to the boundary.
DuPage County beside the ground around it
Illinois as a whole has more high-potential ground than DuPage County: 64.5% of its land, against 19.9% here. Of the 4 counties that border it, 3 have more high-potential ground, Kendall County the most at 100%.
The map rates the ground, not the air in any home.
Local help
DuPage County, Local resources
Radon testing and mitigation in DuPage County
Listed radon businesses with an address in DuPage County:
- IEMA-OHS Radon ProgramIEMA-OHS Radon Program, run by Illinois Emergency Management Agency and Office of Homeland Security, licenses or certifies radon professionals and states the rule for disclosing radon when a home is sold, and answers questions about testing and mitigation in Illinois.Visit the program’s page(opens in a new tab)
- Free and low-cost kitsAsk the program whether it has free or discounted kits, or compare kits you can buy.
- Compare kits
- Professionals in Illinois339 professionals are listed in Illinois.
Listed radon professionals by town: Chicago, Aurora, Naperville, Schaumburg, Bolingbrook, Wheaton, Downers Grove, Elmhurst, Lombard, Carol Stream, Hanover Park, Addison, Woodridge, Glendale Heights, Elk Grove Village, Glen Ellyn, Batavia, West Chicago, Westmont, Lisle, Bloomingdale, Bensenville, Lemont, Warrenville, Itasca, Oakbrook Terrace, Wayne
What Illinois's program says
- Phone
- (800) 325-1245
- Licensing of radon professionals
The Agency also licenses and regulates the individuals who provide radon measurement and mitigation to the public.
- Disclosure when a home is sold or rented
Illinois Radon Awareness Act - This is the legislation that requires the seller to provide to the buyer of any interest in residential real property the IEMA-OHS pamphlet entitled "Radon Testing Guidelines for Real Estate Transactions" and the Illinois Disclosure of Information on Radon Hazards.
What it means
DuPage County, Questions
Questions about radon in DuPage County
Are radon levels high in DuPage County?
In 2017, 33.7% of the radon tests reported to CDC for DuPage County, Illinois were at or above 4 pCi/L, and the median reported pre-mitigation result was 2.7 pCi/L. Of 70 Illinois counties with 30 or more tests for the same period, 52 reported a higher share; pooled, the state comes to 33.7%.
Which counties border DuPage County?
DuPage County borders 4 counties: Cook County, Kane County, Kendall County and Will County.
Products
DuPage County, Products
Testing a home in DuPage County
In DuPage County, 33.7% of 19,401 tests reported to CDC in 2017 reached 4 pCi/L, against 33.7% pooled across Illinois. In Zone 2 a short-term kit (2 to 90 days) is the quick first check in DuPage 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
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
DuPage County, Bordering counties
Counties bordering DuPage County
Calculated by Radon411- Radon levels in Will CountyEPA zone 2
40.0%at or above 4 pCi/L
Median 3.1 pCi/L · 10,776 tests · 6.3 points above DuPage County
- Radon levels in Kane CountyEPA zone 1
36.6%at or above 4 pCi/L
Median 2.8 pCi/L · 8,682 tests · 2.9 points above DuPage County
- Radon levels in Kendall CountyEPA zone 1
35.0%at or above 4 pCi/L
Median 2.8 pCi/L · 3,045 tests · 1.3 points above DuPage County
- Radon levels in Cook CountyEPA zone 2
19.4%at or above 4 pCi/L
Median 1.9 pCi/L · 26,937 tests · 14.3 points below DuPage County
DuPage County, Cities and towns
Cities and towns in DuPage County
DuPage County's population has barely moved since 2020: 934,298 residents on July 1, 2025 against 931,473 then, by the Census Bureau's estimates. Packed into its land, that is 2,850 people per square mile. Chicago, the largest place on its list (2,731,585 residents in all), extends beyond DuPage County, so no share of the total is worked out for it. Testing is reported here more often than across the state: CDC's 19,401 reported tests for 2017 come to 20.8 for every 1,000 residents (2025 estimate), against 10.9 for Illinois.
From Chicago to Wayne, CDC publishes no figure by town: each reads DuPage County's.
| Place | Residents | Since 2020 | Share of residents |
|---|---|---|---|
| Chicagoextends beyond DuPage County | 2,731,585 | −0.4% | Counted whole |
| Auroraextends beyond DuPage County | 181,505 | +0.7% | Counted whole |
| Napervilleextends beyond DuPage County | 153,114 | +2.5% | Counted whole |
| Schaumburgextends beyond DuPage County | 77,249 | −1.5% | Counted whole |
| Bolingbrookextends beyond DuPage County | 74,803 | +1.3% | Counted whole |
| Wheaton | 54,065 | +0.3% | 5.8% |
| Downers Grove | 50,365 | +0.4% | 5.4% |
| Elmhurstextends beyond DuPage County | 46,111 | +0.9% | Counted whole |
| Lombard | 44,399 | −0.1% | 4.8% |
| Bartlettextends beyond DuPage County | 40,855 | −0.4% | Counted whole |
| Carol Stream | 39,315 | −1.1% | 4.2% |
| Hanover Parkextends beyond DuPage County | 36,568 | −2.1% | Counted whole |
Places in DuPage County with a city page: 1 of 3
- Addison
- Woodridge (part)
- Glendale Heights
- Elk Grove Village (part)
- Glen Ellyn
- Batavia (part)
- West Chicago
- Westmont
- Lisle
- Roselle (part)
- Bloomingdale
- Darien
- Villa Park
- Bensenville (part)
- Lemont (part)
- Hinsdale (part)
- Warrenville
- Wood Dale
- Burr Ridge (part)
- Winfield
- Itasca
- Willowbrook
- Clarendon Hills
- Oak Brook
The other 2 places in DuPage County
- Oakbrook Terrace
- Wayne (part)
39 incorporated places, as listed in the U.S. Census Bureau’s 2020 place reference files. “(part)” marks a place that extends into another county. Residents: U.S. Census Bureau population estimates for July 1, 2025 (Vintage 2025). A place that extends beyond DuPage County is counted whole, so it has no share.
DuPage County, Homes
Homes in DuPage County
Of DuPage County's 366,099 homes, 58% are detached houses, against 58% across Illinois; 25% are in buildings of five or more homes. Much of DuPage County is recent building: 14% of its homes have gone up since 2000 and the middle year built is 1978, against 1970 for Illinois. 73% of occupied homes are lived in by their owner (Illinois: 67%); in the rest a tenant can run a test, but a fix is the landlord's to make.
| Homes | DuPage County | Illinois |
|---|---|---|
| Housing units | 366,099 | 5,443,501 |
| Detached houses | 58% | 58% |
| In buildings of 5 or more | 25% | 22% |
| Mobile homes | under 1% | 2% |
| Built before 1960 | 18% | 38% |
| Built since 2000 | 14% | 16% |
| Middle year built | 1978 | 1970 |
| Owner-occupied | 73% | 67% |
Census Bureau, American Community Survey, 2019 to 2023: estimates from a sample of homes, looser for a small place. Shares by Radon411.