Short-term kit
RA100 short-term liquid scintillation radon test kit
- Lab fee extra
Method: Liquid scintillation
In home: 48 to 96 hours
Locations and reports
Radon Levels in Caldwell County, North Carolina
EPA puts Caldwell County in Zone 2, its middle radon zone, and only 6 radon tests from it are on file with CDC (2022). Homes with elevated levels occur in all three zones, so only a test measures yours.
Data checked By Radon411Methodology
Share at 4+ pCi/L
27.6%
5.0 pts above NC
- Caldwell
- 27.6%
- NC
- 22.6%
861 tests, 2008 to 2017
Median result
2.5pCi/L
Below action level
- Caldwell
- 2.5 pCi/L
- EPA
- 4.0 pCi/L
Midpoint of the tests, 2008 to 2017
Tests reported
861
20th of 75 by tests
- Caldwell
- 861
- Wake
- 9,694
Reported to CDC before any fix, 2008 to 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 NC
29 of 75
Middle half
- Caldwell
- 27.6%
- Transylvania
- 47.8%
By share, of 75 with 30+ tests
Read a result for Caldwell County
Starts at Caldwell County's median, 2.5 pCi/L
EPA’s own thresholds; the figures are the area’s, never this home’s.
EPA’s reading of 2.5 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. Caldwell County's median reported result, 2008 to 2017.
The data
Caldwell County, At a glance
Caldwell County at a glance
Predicted: EPA radon zone
EPA Zone 2: moderate predicted potential
Caldwell County is a
USGS geologic potential: Moderate across 99% of the county's area
Predicted: EPA Map of Radon Zones
Measured: tests reported to CDC
Radon tests reported for Caldwell County, 2022
| Year | Share of reported tests at or above 4 pCi/L |
|---|---|
| 2014 | 22.8% |
| 2020 | 26.6% |
| 2021 | 20.2% |
| 2022 | 50.0% |
2022: 50.0%. Across these years the share ran from 20.2% to 50.0%. Each column counts radon tests reported to CDC that year, not homes.
What these figures count
Only 6 tests were reported to CDC for Caldwell County over 2022, 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: 2022. Measured data period: 2005 to 2022 (every CDC figure on file).
Caldwell County, Compared
Caldwell County radon figures, compared
Calculated by Radon411Caldwell County's 861 reported tests over the 2008 to 2017 laboratory totals had a middle value of 2.5 pCi/L and a maximum of 217.5 pCi/L, and 27.6% reached 4 pCi/L. North Carolina as a whole (99 North Carolina counties, pooled) comes to 22.6%: 5.0 points lower than here.
The newest figure, in 2022, counts only 6 tests (50.0% at or above 4 pCi/L), too few to compare, so this reading uses the 861-test figure.
Among its state's counties it ranks 29th of 75 North Carolina counties with 30 or more tests for the same period. Statewide for the same period, Transylvania County reported the highest share (47.8%) and Nash County the lowest (0.0%).
Below the action level, 317 tests (36.8%) came in under 2 pCi/L, against 55.6% statewide, and 306 tests (35.5%) fell between 2 and 4, against 21.8% statewide. The busiest year on file was 2020, with 274 tests reported; the quietest, 2022, had 6.
EPA's 1993 zone map puts Caldwell County in Zone 2, a predicted county average between 2 and 4 pCi/L. USGS geology rates 99% of the county's land moderate radon potential.
Next door, the shares run from 24.8% in Catawba County to 45.1% in Watauga County, with Catawba County below Caldwell County. Over 3 years of annual figures the share fell 2.6 points, from 22.8% in 2014 to 20.2% in 2021; its peak was 26.6% in 2020.
CDC also counts 107 tests taken after mitigation in Caldwell County for the same period: tests in homes where a fix was already in.
Caldwell CountyNorth Carolina, pooled
| Year | Tests | Caldwell County, at or above 4 pCi/L | North Carolina, pooled |
|---|---|---|---|
| 2014 | 127 | 22.8% | 21.9% |
| 2020 | 274 | 26.6% | 21.1% |
| 2021 | 248 | 20.2% | 14.9% |
Pooled shares: Radon411's sum of CDC's county counts for one period.
Caldwell County, Geology
The ground under Caldwell County
PredictedMost of the ground under Caldwell County is one class on USGS's geologic map: 98.5% of its land is moderate radon potential, with 1.5% high. The map puts 57.3% of Caldwell County in the area it calls Inner Piedmont Belt and 41.2% in Blue Ridge, with one smaller area beside them. USGS gives the first a radon index of 11 and the second 10, both in the moderate band (9 to 11).
| Area | The rock, in USGS's words | Potential | Radon index | Share of land |
|---|---|---|---|---|
| Inner Piedmont Belt | Proterozoic through Cambrian biotite gneiss and schist, and mica schist. | Moderate | 11 | 57.3% |
| Blue Ridge | Granite, pegmatite, monazite, schist, and gneiss. | Moderate | 10 | 41.2% |
| Chauga Belt | Monzonitic to granodioritic gneiss. | High | 12 | 1.5% |
Names, descriptions and indexes: U.S. Geological Survey, Geologic Radon Potential Map (2025). Shares: Radon411, from the map cut to the boundary.
Caldwell County beside the ground around it
On high-potential ground Caldwell County is close to North Carolina as a whole: 1.5% of its land against 1.3%. Of the 6 counties that border it, 1 has more high-potential ground, Burke County the most at 5.8%.
The map rates the ground, not the air in any home.
Local help
Caldwell County, Local resources
Radon testing and mitigation in Caldwell County
- North Carolina Radon ProgramNorth Carolina Radon Program, run by NCDHHS, answers questions about testing, mitigation and the rules in North Carolina.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 North Carolina2 professionals are listed in North Carolina.
What North Carolina's program says
- Licensing of radon professionals
The North Carolina Radon Program is presently developing a Radon Proficiency Program as directed by Session Law 2023-91 House Bill 782 .
What it means
Caldwell County, Questions
Questions about radon in Caldwell County
Are radon levels high in Caldwell County?
In 2022, 50.0% of the radon tests reported to CDC for Caldwell County, North Carolina were at or above 4 pCi/L, and the median reported pre-mitigation result was 3.0 pCi/L. Of 75 North Carolina counties with 30 or more tests for the same period, 28 reported a higher share; pooled, the state comes to 22.6%.
Which counties border Caldwell County?
Caldwell County borders 6 counties: Burke County, Alexander County, Avery County, Watauga County, Catawba County and Wilkes County.
Products
Caldwell County, Products
Testing a home in Caldwell County
In Caldwell County, 27.6% of 861 tests reported to CDC over the 2008 to 2017 laboratory totals reached 4 pCi/L, against 22.6% pooled across North Carolina. In Zone 2 a short-term kit (2 to 90 days) is the quick first check in Caldwell County; a long-term test tells the year-round average.
Test kits and monitors3
See every kit and monitor
Long-term kit
RL116 long-term radon test kit
- Lab fee extra
Method: Alpha track
In home: 90 days to 12 months
Monitor
Wave Plus battery radon and air quality monitor
- C-NRPP 2024/25: Not included
- Battery
- Bluetooth
- App only
Method: Alpha spectrometry
- See every kit and monitor Test kits and monitors
Test kits and monitors: 1 of 3
Explore
Caldwell County, Bordering counties
Counties bordering Caldwell County
Calculated by Radon411- Radon levels in Watauga CountyEPA zone 1
45.1%at or above 4 pCi/L
Median 3.5 pCi/L · 1,215 tests · 17.5 points above Caldwell County
- Radon levels in Wilkes CountyEPA zone 2
44.3%at or above 4 pCi/L
Median 3.5 pCi/L · 402 tests · 16.7 points above Caldwell County
- Radon levels in Avery CountyEPA zone 2
38.8%at or above 4 pCi/L
Median 2.8 pCi/L · 160 tests · 11.2 points above Caldwell County
- Radon levels in Alexander CountyEPA zone 2
32.8%at or above 4 pCi/L
Median 2.5 pCi/L · 311 tests · 5.2 points above Caldwell County
- Radon levels in Burke CountyEPA zone 2
28.3%at or above 4 pCi/L
Median 2.4 pCi/L · 940 tests · 0.7 points above Caldwell County
- Radon levels in Catawba CountyEPA zone 2
24.8%at or above 4 pCi/L
Median 2.0 pCi/L · 1,259 tests · 2.8 points below Caldwell County
Caldwell County, Cities and towns
Cities and towns in Caldwell County
The Census Bureau estimates 81,105 residents in Caldwell County for July 1, 2025, 523 more than in 2020 (+0.6%). That works out to 172 people per square mile of land. Hickory, the largest place on its list (45,975 residents in all), extends beyond Caldwell County, so no share of the total is worked out for it. Testing is reported here more often than across the state: CDC's 861 reported tests for 2008 to 2017 come to 10.6 for every 1,000 residents (2025 estimate), against 6.5 for North Carolina.
From Hickory to Cedar Rock, CDC publishes no figure by town: each reads Caldwell County's.
| Place | Residents | Since 2020 | Share of residents |
|---|---|---|---|
| Hickoryextends beyond Caldwell County | 45,975 | +5.2% | Counted whole |
| Lenoir | 18,372 | +0.1% | 22.7% |
| Sawmills | 5,105 | +1.3% | 6.3% |
| Granite Falls | 4,964 | +0.4% | 6.1% |
| Hudson | 3,786 | +0.1% | 4.7% |
| Gamewell | 3,713 | +0.5% | 4.6% |
| Cajah's Mountain | 2,702 | Level | 3.3% |
| Blowing Rockextends beyond Caldwell County | 1,324 | −3.5% | Counted whole |
| Rutherford Collegeextends beyond Caldwell County | 1,220 | +0.7% | Counted whole |
| Rhodhissextends beyond Caldwell County | 996 | +0.8% | Counted whole |
| Cedar Rock | 302 | +0.7% | 0.4% |
11 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). A place that extends beyond Caldwell County is counted whole, so it has no share.
Caldwell County, Homes
Homes in Caldwell County
Of Caldwell County's 37,231 homes, 72% are detached houses, against 65% across North Carolina; 16% are mobile homes. The homes are older than North Carolina's as a whole: half were built before 1981 (1990 for North Carolina), and 21% date from before 1960. 74% of occupied homes are lived in by their owner (North Carolina: 66%); in the rest a tenant can run a test, but a fix is the landlord's to make.
| Homes | Caldwell County | North Carolina |
|---|---|---|
| Housing units | 37,231 | 4,815,195 |
| Detached houses | 72% | 65% |
| In buildings of 5 or more | 5% | 14% |
| Mobile homes | 16% | 11% |
| Built before 1960 | 21% | 14% |
| Built since 2000 | 16% | 33% |
| Middle year built | 1981 | 1990 |
| Owner-occupied | 74% | 66% |
Census Bureau, American Community Survey, 2019 to 2023: estimates from a sample of homes, looser for a small place. Shares by Radon411.