Radon Levels & Zone Map in Wake County, NC
Direct Answer for basement and lowest-level tests: Wake County sits in the gray zone. The map helps, but your own reading matters more than the countywide signal.
Treat the map as a hint, not the answer
Zone 2 is the gray area. A real reading is what decides whether you retest, track, or price mitigation.
Official source shows a highest reported county value, not a county average.
2.0-3.9 pCi/L usually means retest or track. 4.0+ is where EPA action and quote planning start to matter.
No reading: test first. Borderline results often need retest or long-term tracking.
Measured Radon Data
Wake County evidence before the next step
Wake County, NC has more than the EPA map: North Carolina DHHS exposes 257.0 pCi/L high-end signal for updated 2025-08-06.
Source window
updated 2025-08-06
Processed verdict
Official high-end signal
Sparse confidence - 47/100
Highest measured
257.0 pCi/L
94th percentile in-state
4.0+ signal
Not available
n/a in-state
High-end signal
257.0 pCi/L
94th percentile in-state
County-specific verdict
Wake County has an official high-end county result of 257.0 pCi/L, but no county average in this source.
Wake County is not being judged from an average table here. North Carolina DHHS exposes a highest measured county value of 257.0 pCi/L, so the useful decision is proof of local spike potential: test the home directly, then use a 4.0+ property result for mitigation pricing. It ranks at the 94th percentile for high-end readings among measured counties in the state.
Real-estate use
Buyer or seller use: do not negotiate from the highest county value alone. Use it to justify requiring a fresh lowest-level property test, then price quotes or credits only from the home's own 4.0+ result.
Wake County should be treated as a direct-test county: the official high-end value reaches 257.0 pCi/L, but the source cannot tell whether a specific home is high until that home is tested.
Choose Next StepHigh-end-source answer
What does the highest reported radon result mean in Wake County?
North Carolina DHHS reports a highest measured county value of 257.0 pCi/L for Wake County. That is a high-end local signal, not a county average. The practical answer is to test the property and let the home's result decide mitigation, retesting, or credit math.
Pick the situation that matches you
You should not need to read the whole guide before clicking one of these. Start with the lane that matches your current stage, then come back for the deeper reference only if you still need it.
Jump into a prefilled Wake County action plan based on the result you already have, instead of starting from a generic cost page.
I have not tested yet
Do not price mitigation blind. Get the first number, then decide whether you need monitoring, quotes, or nothing at all.
My result is 2.0-3.9
Usually retest or track first. If the reading keeps showing up, use the local action plan to decide whether pricing makes sense.
My result is 4.0+
This is the EPA action line. Use the local cost page before calling contractors so you know the likely scope, timing, and budget.
I am buying or selling
Turn the reading into a credit or repair number before negotiation starts. This is the faster path than arguing from a generic article.
Already tested once and just want to watch the number trend?
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County Evidence Snapshot
Wake County testing context
Wake County is a gray-zone county: the EPA map is useful context, but the local housing profile and your own home test decide the next step.
EPA map signal
Zone 2
County-level predicted indoor screening range, not a home-level test result.
Housing base
466,760
99th percentile among 100 NC counties with data.
Older housing share
80.5%
98th percentile in-state; older homes often need clearer test placement decisions.
Median home value
$385,700
Used as context for whether mitigation is a small maintenance item or a negotiation issue.
Measured Radon Data
North Carolina DHHS Radon Data Map
updated 2025-08-06
Highest measured
257.0 pCi/L
At or above 4.0
Not available
Maximum reported
257.0 pCi/L
Avg. tests/year
Not available
NCDHHS says the public map shows the highest measured radon level in each county from two test kit companies and one continuous-monitor leasing company. RadonVerdict stores that value only as a high-end county signal, not as a county average or a prediction for a particular building.
RadonVerdict Processed Verdict
Official high-end signal
High-end rank
94th percentile
257.0 pCi/L
4.0+ rank
n/a
Not available at or above 4.0
High-end rank
94th percentile
257.0 pCi/L
Test volume rank
n/a
Not available
How to use this county data
Data source
Highest reported county reading
North Carolina values come from the DHHS county radon map export. The source publishes each county's highest measured value, so RadonVerdict treats it as a high-end spike signal rather than a county average.
What the numbers show
High readings have occurred
This source gives the highest measured value, not a county average. Use it to know high readings have happened locally, then verify your own home.
Nearby comparison
Nearby comparison: Closest counties by highest reported reading: Haywood County (234.0 pCi/L) is just lower, and Alexander County (288.0 pCi/L) is just higher.
How this helps
Use this to see that high readings have happened locally, then test the specific property before assuming the county value is typical.
What the data says
Wake County, NC is measurement-backed for updated 2025-08-06.. The high-end signal reaches 257.0 pCi/L.
Wake County, NC sits at the n/a for measured average, n/a for 4.0+ share, 94th percentile for high-end readings, and n/a for test volume among 100 measured counties in the state.
What to do with it
Wake County should be treated as a direct-test county: the official high-end value reaches 257.0 pCi/L, but the source cannot tell whether a specific home is high until that home is tested.
Retest trigger: a 2.0-3.9 pCi/L home result should be confirmed because the official source shows local high-end readings up to 257.0 pCi/L, even though it does not publish a county average here.
Sparse confidence (47/100) from North Carolina DHHS plus high-end county measurement context.
No reading yet
No reading yet: use the official high-end signal as a reason to test the home, not as a substitute for a home result.
2.0-3.9 result
2.0-3.9 pCi/L: confirm with a follow-up or longer-term test because this source proves elevated readings occur locally but does not show the full county distribution.
4.0+ result
4.0+ pCi/L: use the result for mitigation quotes, repair scope, or seller-credit negotiation; the county signal is no longer the deciding input.
Source hierarchy: North Carolina DHHS is used for this county, with EPA zone and Census housing data kept as supporting context. North Carolina values come from the DHHS county radon map export. The source publishes each county's highest measured value, so RadonVerdict treats it as a high-end spike signal rather than a county average.
Direct Answer
What radon risk level should homeowners assume in Wake County?
Wake County is currently categorized as EPA Zone 2 (Moderate Risk). Test all lived-in levels and confirm with follow-up testing if elevated.
| Evidence | Value |
|---|---|
| Area | Wake County, NC |
| EPA Zone | Zone 2 |
| Primary Recommendation | Perform direct radon testing in the lowest livable level |
Your Radon Reading
Enter your home's measured level. This county source publishes a highest reported value, so the slider does not start from a county average.
Elevated - Consider Action
Your reading is below the US EPA action level (4.0 pCi/L), but this range still warrants follow-up testing. The World Health Organization uses 2.7 pCi/L as a tighter reference point.
If this was just a one-time snapshot, confirm it with another test or with longer tracking. If this level persists, planning mitigation is reasonable, especially for homes with frequent basement use, children, or pending real-estate transactions. Scroll down to see your estimated cost.
Understanding Radon Levels: Complete Reference
Below 2.0 pCi/L - Lower Concern, Keep Testing
Below both the EPA (4.0) and WHO (2.7) action reference levels. This usually means mitigation is not the next immediate step after a confirmed result. The average outdoor radon level is approximately 0.4 pCi/L, and there is no known risk-free indoor level. Periodic testing is still recommended because levels can change over time due to seasonal variations, changes in home ventilation, or foundation settling.
-4.0
2.0 - 4.0 pCi/L - Elevated, Consider Action
Exceeds the World Health Organization's reference level of 2.7 pCi/L but falls below the US EPA action threshold. The EPA states that homeowners should "consider fixing" homes in this range, especially if the home has a basement used as living space, if children are present, or in connection with a real estate transaction. Practical next step: run a confirmatory long-term test, then compare mitigation quotes if levels remain elevated.
-8.0
4.0 - 8.0 pCi/L - Action Recommended
Exceeds the EPA action level of 4.0 pCi/L. The EPA and Surgeon General strongly recommend mitigation within a few months. At this level, prioritize confirmatory testing and contractor planning. Standard sub-slab depressurization systems typically reduce indoor levels by 80-99%.
Above 8.0 pCi/L - Urgent Action Required
At these levels, the EPA recommends expedited mitigation - ideally within weeks, not months. Occupants should minimize time in lower-level rooms until the system is installed. Use a certified mitigator and request priority scheduling to shorten high-exposure time. Many mitigators offer priority scheduling for homes above 8.0 pCi/L.
Why Radon is Worth Monitoring in Wake County
Wake County falls in EPA Zone 2, where the predicted indoor screening range is between 2.0 and 4.0 pCi/L. Even when the countywide map signal sits below the EPA action level, geological variability means that some individual homes will still test above 4.0 pCi/L.
The soil composition in this area typically includes a mix of sedimentary formations that can contain moderate uranium deposits. Homes with basement or crawlspace foundations are particularly susceptible, as they provide more pathways for soil gas entry.
The World Health Organization recommends action at 2.7 pCi/L - well below the US EPA threshold. If you have children, spend significant time in below-grade rooms, or are buying/selling a home, testing is essential even in a Zone 2 area.
Radon & Health: What the Science Says
lung cancer
from radon
4.0 pCi/L
Radon is a Class A carcinogen - the same classification as asbestos and tobacco smoke. The National Academy of Sciences estimates that radon causes approximately 21,000 lung cancer deaths annually in the United States, making it the leading environmental cause of cancer death.
Unlike smoking, radon exposure is involuntary and often invisible. There is no safe level of radon - risk increases linearly with exposure. The good news: radon mitigation systems are highly effective, typically reducing indoor levels by 80-99% within hours of activation.
Source: US Environmental Protection Agency, "A Citizen's Guide to Radon" (EPA 402/K-12/002). National Academy of Sciences, Biological Effects of Ionizing Radiation (BEIR VI) Report, 1999.
Step 1: Test Your Home
Testing is the only way to know your home's radon level. Zone data tells you the regional risk, but your home could be significantly higher or lower than the countywide pattern. For most homeowners, the right first purchase is a low-cost short-term test kit.
A digital monitor is a better fit after your first result, for seasonal re-checks, or to keep tracking levels after mitigation.
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Already Know Your Level?
If your test shows 4.0 pCi/L or higher, get an itemized cost estimate specific to Wake County - including regional labor rates and permit requirements.
Get Mitigation Cost Estimate ->NC Radon Regulations
North Carolina requires sellers to complete a Residential Property and Owners' Association Disclosure Statement, covering environmental hazards.
North Carolina does not require specific radon licensing. NRPP or AARST certification is recommended.
How to Test for Radon in Wake County
Buy a Test Kit
Purchase a short-term charcoal test kit online or from a local hardware store. Cost: $15-$30. Place it in the lowest livable level of your home.
Wait 2-7 Days
Keep doors and windows closed (except normal entry/exit) during the test period. Avoid running whole-house fans. Mail the kit to the lab provided.
Read Your Results
If results are below 4.0 pCi/L, re-test every 2 years or use a monitor for ongoing tracking. If above 4.0, use our cost calculator to see mitigation options.
Related Radon Resources for Wake County
Explore Other NC Counties
Official State Resource
North Carolina radon program and rules
Use the state program link to verify local radon guidance, disclosure language, and contractor credential expectations before you act on an estimate.
Disclosure rule tracked
North Carolina requires sellers to complete a Residential Property and Owners' Association Disclosure Statement, covering environmental hazards.
Credential note
North Carolina does not require specific radon licensing. NRPP or AARST certification is recommended.
Sources & Methodology
Radon zone classifications for Wake County are sourced from the EPA's Map of Radon Zones, which uses geological surveys, indoor radon measurements, and soil permeability data to assign each county a risk tier.
Disclaimer: Zone data represents county-level screening ranges and cannot predict the radon level in any specific home. Testing is the only reliable method to determine your home's radon concentration. This content is for informational purposes and is not medical advice.
Content review: Source-level retrieval dates
Editorial and Data Transparency
- Author
- RadonVerdict Data Team (Public Data and Cost Modeling)
- Content Review
- Source-level dates shown below
- Data Retrieved At
- 2026-02-24
Primary Sources
- EPA Map of Radon Zones (retrieved 2026-02-21)
- EPA A Citizen's Guide to Radon (retrieved 2026-05-05)
- CDC Environmental Public Health Tracking - Radon Testing (retrieved 2026-05-05)
- North Carolina DHHS Radon Data Map (retrieved 2026-05-06)
- Official NC radon program
- US Census Bureau, 2018-2022 American Community Survey 5-Year Estimates (retrieved 2026-02-24)