Tennessee Radon Map, Levels & Testing Guide
Browse the 31 listed county pages surfaced for Tennessee. Open a listed county to compare its EPA zone, source caveats, testing meaning, and when mitigation pricing becomes worth checking.
High Risk
Moderate
Low Risk
Official Evidence in Tennessee
31 of 31 listed counties have official evidence
Open a county page to see the processed verdict: source confidence, local burden, state percentile, and the next step for no reading, 2.0-3.9, or 4.0+ pCi/L.
100%
covered
Measured
31
State source
31
CDC source
0
Needs source detail
0
Measured Risk Leaders in Tennessee
County rankings from actual reported radon tests
These lists rank the visible Tennessee 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.
31
measured counties
State-level verdict
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 31 visible county measurement rows. 15 counties cross the high measured-burden band, so those pages should answer testing and 4.0+ action questions most directly.
First-click counties
Open Sevier County first when you need the strongest local answer. It is tagged Test-now from 46.7% 4.0+ - 6.5 pCi/L primary - 150 tests. 26 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 31 state-source 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.
Sevier County
TN Health
46.7% 4.0+ - 6.5 pCi/L primary - 150 tests
Sevier County is a first-click page: 46.7% of reported tests at or above 4.0 and 6.5 pCi/L primary result. Route no-reading users to a test now and 4.0+ users to quote or credit planning.
Sullivan County
TN Health
44.0% 4.0+ - 6.5 pCi/L primary - 665 tests
Sullivan County is a first-click page: 44.0% of reported tests at or above 4.0 and 6.5 pCi/L primary result. Route no-reading users to a test now and 4.0+ users to quote or credit planning.
Loudon County
TN Health
51.4% 4.0+ - 5.5 pCi/L primary - 252 tests
Loudon County is a first-click page: 51.4% of reported tests at or above 4.0 and 5.5 pCi/L primary result. Route no-reading users to a test now and 4.0+ users to quote or credit planning.
Claiborne County
TN Health
39.3% 4.0+ - 7.2 pCi/L primary - 28 tests
Claiborne County is a first-click page: 39.3% of reported tests at or above 4.0 and 7.2 pCi/L primary result. Route no-reading users to a test now and 4.0+ users to quote or credit planning.
Highest 4.0+ share
Primary result 5.5 pCi/L - high-end 78.1 pCi/L
TN Health
Primary result 6.5 pCi/L - high-end 113.0 pCi/L
TN Health
Primary result 5.6 pCi/L - high-end 31.0 pCi/L
TN Health
Primary result 6.5 pCi/L - high-end 179.8 pCi/L
TN Health
Primary result 4.5 pCi/L - high-end 15.3 pCi/L
TN Health
Highest high-end reading
4.0+ share 44.0% - primary result 6.5 pCi/L
TN Health
4.0+ share 37.4% - primary result 5.1 pCi/L
TN Health
4.0+ share 40.9% - primary result 5.0 pCi/L
TN Health
4.0+ share 46.7% - primary result 6.5 pCi/L
TN Health
4.0+ share 29.5% - primary result 3.9 pCi/L
TN Health
Most reported tests
4.0+ share 37.4% - primary result 5.1 pCi/L
TN Health
4.0+ share 29.5% - primary result 3.9 pCi/L
TN Health
4.0+ share 41.4% - primary result 5.3 pCi/L
TN Health
4.0+ share 21.4% - primary result 3.6 pCi/L
TN Health
4.0+ share 44.0% - primary result 6.5 pCi/L
TN Health
Measured pattern
Among 31 visible counties with measurement tables, 15 land in the high measured-burden band and 26 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 confidence
All measured rows shown here use state-specific official sources, so this hub can make source-backed county comparisons without leaning on a national fallback.
Already Tested
View Tennessee 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
Tennessee 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
Tennessee requires sellers to complete a Residential Property Condition Disclosure covering known defects and hazards.
Credential note
Tennessee does not require specific radon licensing.
Already tested? Get your itemized mitigation cost estimate.
View Tennessee Mitigation Cost Estimates ->