South Carolina Radon Map, Levels & Testing Guide
Browse the 46 listed county pages surfaced for South Carolina. Open a listed county to compare its EPA zone, source caveats, testing meaning, and when mitigation pricing becomes worth checking.
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Official Evidence in South Carolina
46 of 46 listed counties have official evidence
Open a county page to see the official source context: measurement fields, local burden, state percentile, and the next step for no reading, 2.0-3.9, or 4.0+ pCi/L.
100%
covered
Measured
46
State source
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CDC source
46
Needs source detail
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Measured Risk Leaders in South Carolina
County rankings from actual reported radon tests
These lists rank the visible South Carolina county pages by measured radon signals, not by the EPA zone label alone. Use them to spot where the state hub has a real data story before opening individual county pages.
46
measured counties
State-level evidence read
This hub has measured high-burden counties, so the first click should be evidence-led.
The state hub is now doing a decision job: it separates first-click counties, retest counties, and lower-signal counties from 46 visible county measurement rows. 1 counties cross the high measured-burden band, so those pages should answer testing and 4.0+ action questions most directly.
First-click counties
Open Oconee County first when you need the strongest local answer. It is tagged Test-now from 42.6% 4.0+ - 4.8 pCi/L primary - 1,035 tests. 3 visible measured counties are elevated or high enough to review before lower-signal counties.
Buyer/seller lane
Buyer/seller lane: start with the elevated or high counties, require a fresh lowest-level test, and turn any 4.0+ property result into quote or credit math. The hub has 46 CDC-backed county rows to support that routing.
Retest lane
Retest lane: 2.0-3.9 pCi/L deserves more caution in the elevated/high county set than in lower-signal counties. The hub should send those users to county pages before product or cost paths.
Best county pages to open first
Start with these local evidence pages
Ranked by measured burden, 4.0+ share, test volume, and whether the EPA zone understates the measurement signal.
Oconee County
CDC Tracking
42.6% 4.0+ - 4.8 pCi/L primary - 1,035 tests
Oconee County is a first-click page: 42.6% of reported tests at or above 4.0 and 4.8 pCi/L primary result. Route no-reading users to a test now and 4.0+ users to quote or credit planning.
Pickens County
CDC Tracking
23.6% 4.0+ - 3.5 pCi/L primary - 969 tests
Pickens County should be opened before lower-signal counties: 23.6% of reported tests at or above 4.0 and 3.5 pCi/L primary result. It is strong enough for testing and retesting language on the hub.
Edgefield County
CDC Tracking
25.0% 4.0+ - 2.1 pCi/L primary - 10 tests
Edgefield County should be opened before lower-signal counties: 25.0% of reported tests at or above 4.0 and 2.1 pCi/L primary result. It is strong enough for testing and retesting language on the hub.
Greenville County
CDC Tracking
19.6% 4.0+ - 2.9 pCi/L primary - 7,077 tests
Greenville County belongs in the retest lane: 19.6% of reported tests at or above 4.0 and 2.9 pCi/L primary result. A 2.0-3.9 home result should be confirmed before the user dismisses it.
Highest 4.0+ share
Primary result 4.8 pCi/L - high-end 69.7 pCi/L
CDC Tracking
Primary result 2.1 pCi/L - high-end 5.7 pCi/L
CDC Tracking
Primary result 3.5 pCi/L - high-end 129.0 pCi/L
CDC Tracking
Primary result 2.9 pCi/L - high-end 13.6 pCi/L
CDC Tracking
Primary result 1.8 pCi/L - high-end 5.3 pCi/L
CDC Tracking
Highest high-end reading
4.0+ share 19.6% - primary result 2.9 pCi/L
CDC Tracking
4.0+ share 23.6% - primary result 3.5 pCi/L
CDC Tracking
4.0+ share 42.6% - primary result 4.8 pCi/L
CDC Tracking
4.0+ share 11.1% - primary result 1.8 pCi/L
CDC Tracking
4.0+ share 19.1% - primary result 2.7 pCi/L
CDC Tracking
Most reported tests
4.0+ share 19.6% - primary result 2.9 pCi/L
CDC Tracking
4.0+ share 19.1% - primary result 2.7 pCi/L
CDC Tracking
4.0+ share 42.6% - primary result 4.8 pCi/L
CDC Tracking
4.0+ share 23.6% - primary result 3.5 pCi/L
CDC Tracking
4.0+ share 11.1% - primary result 1.8 pCi/L
CDC Tracking
Measured pattern
Among 46 visible counties with measurement tables, 1 land in the high measured-burden band and 3 land in high or elevated measured-burden bands. That lets this hub rank counties by observed test distribution instead of repeating the EPA map.
Map vs measurements
3 elevated measured counties are not EPA Zone 1. Those are the pages where the actual test distribution matters more than a map-only answer.
Source strategy
The measured rows shown here use CDC Tracking. This is still official evidence, but the hub should keep source caveats visible until a stable state table is available.
Already Tested
View South Carolina Cost Estimates
If you already have a radon result, skip the directory and move straight to local price guidance.
Understand the Number
2.0 vs 4.0 vs 8.0 pCi/L
Use the parent levels guide if you need the plain-English meaning of a radon result before browsing counties.
Need a Number First
Read the Testing Guide
Use the fastest valid radon test setup before you compare quotes or ask whether mitigation is worth it.
Browse Counties
Jump to the Directory
Open your county to see its EPA zone, testing meaning, and the point where mitigation becomes worth pricing.
Official State Resource
South 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
South Carolina requires sellers to complete a Seller's Disclosure of Property Condition, covering known defects.
Credential note
South Carolina does not require specific radon licensing.
Already tested? Get your itemized mitigation cost estimate.
View South Carolina Mitigation Cost Estimates ->