Tennessee Radon Authority
Updated October 17, 2026

Henderson County radon · Lexington & rural communities

Henderson County radon. Zone 2 risk, zero tests in the state dataset.

Neither Lexington’s published code nor the new state-enforcement path for unincorporated areas requires radon-resistant construction. Meanwhile, Tennessee’s 2022–2023 dashboard logged no Henderson County test events.

Research checked October 16, 2026Primary records and live directories
Editorial cutaway illustration of radon moving through soil and foundation openings beneath a West Tennessee brick home
A blank public dataset is a measurement gap—not proof of a radon-free county.

Radon in Henderson County, Tennessee: quick answers

EPA zone: Zone 2Region: West TennesseeState test data: No 2022–2023 state test records for this county

Is radon a problem in Henderson County, Tennessee?

It can be. Henderson County is in EPA Zone 2, where the predicted average indoor screening level is 2 to 4 pCi/L. Homes above EPA's 4 pCi/L action level are found in every zone, so a test is the only way to know your home's level.

Do new homes in Henderson County, TN have to be built radon-resistant?

No. Unincorporated Henderson County now falls under the state's 2018 code, which leaves out the radon appendix, and Lexington's published 2012 code lists no appendices. Local code details

How do I test my home for radon in Henderson County?

Order a free short-term kit from the Tennessee Radon Program online or by calling 1-800-232-1139. Place it on the lowest lived-in floor, about 3 feet off the floor, for 3 to 5 days, then mail it back right away. How to test your home

What radon level means I should fix my home?

EPA recommends fixing your home if radon is 4 pCi/L or higher, and considering a fix between 2 and 4 pCi/L. Confirm a high short-term result with a second test first. What your result means

Who can test or fix radon in Henderson County?

Tennessee doesn't license radon professionals, so look for NRPP or NRSB certification. Search both national directories by ZIP code; certified professionals often serve Henderson County from nearby cities. How to choose a radon professional

01 / QUICK READ

Moderate predicted potential, no public test record, and no radon-ready mandate.

Test every Henderson County home—including new construction.

Unincorporated Henderson County is now on the state’s 2018 IRC path, but the state rule adopts Appendix Q only. Lexington’s published 2012 IRC adoption lists no appendices. Neither path includes the radon appendix. [1] [2] [3]

Bottom line
No dashboard tests and no code mandate make individual testing more important, not less.
Zone 2Moderate-potential designation: predicted average indoor levels of 2–4 pCi/L. [4]
No EventsTwo county-labeled dashboard checks for the combined 2022–2023 view. [5]
0 localNRPP- or NRSB-listed measurement professionals based in Henderson County. [6] [7]
62 miDistance from Lexington to the nearest visible NRPP listing, in Lawrenceburg. [6]
02 / RISK & DATA

The state dashboard has no Henderson County tests to summarize.

“No Events” describes the 2022–2023 dataset. It does not describe the air inside any home.

EPA radon potential
Zone 2

Predicted average indoor radon from 2 to 4 pCi/L. The zone is a broad planning category, not a property-level measurement. [4]

COUNTY LABEL VERIFIED ON 2 LOADS

Tennessee Radon Testing dashboard

No EventsAverage field · Henderson County · 2022–2023 combined view

The tooltip itself read “County: Henderson” on two separate loads. Average read “No Events”; median and maximum were blank. No county values are inferred or substituted. [5]

The lower charts are health-region aggregates—not Henderson County counts.

Selecting a county did not change the dashboard’s pre- and post-mitigation band charts. No count or percentage from those regional bars is presented here as Henderson County data.

03 / BUILDING CODES

The county’s enforcement path changed this week—but radon construction remains optional.

The unincorporated county and Lexington have separate code systems. Neither published path adopts a radon appendix.

APPENDIX F NOT ADOPTED

Unincorporated Henderson County

On October 13, 2026, a motion to opt out of Tennessee’s residential inspection program failed 9–5; ten votes were required. The county therefore falls under State Fire Marshal residential enforcement. The state rule uses the 2018 IRC plus Appendix Q only, not Appendix F for radon. [1] [2]

Result: radon-resistant new construction is optional. The exact start date for state inspection after the failed vote is not yet confirmed.
CURRENT EDITION CONFLICTS

City of Lexington

Lexington’s MTAS-codified Title 12 adopts the 2012 IRC through Ordinance #201802, with no appendices listed. That leaves Appendix F unadopted and radon-resistant construction optional under the published code. [3]

A city flowchart instead references 2018 International Building Codes. Confirm the current edition and exemption status with Lexington Codes at 731.968.7091. [8]
NO LOCAL RULE FOUND

Schools & public buildings

No Henderson County or Lexington rule was found requiring radon testing in schools or public buildings. Tennessee law encourages school indoor-air programs that may include radon testing; it does not mandate them. [9]

A 2018 bill proposed mandatory school testing, but the current statute still uses voluntary language. [10]
KNOWN-CONDITION DISCLOSURE

Real-estate transactions

Tennessee’s standard disclosure form names “radon gas” among environmental hazards on a Yes/No/Unknown awareness question. It does not require the seller to test. [11]

The form advises buyers to use inspection contingencies. A disclosure is not a substitute for a measurement in the home being purchased.

How do I find a certified radon professional in Henderson County?

Tennessee doesn't license radon testers or mitigators, so national certification is the best way to check qualifications. The Tennessee Radon Program points residents to two directories: search them by ZIP code and widen the radius if nothing is listed nearby.

Search NRPPSearch NRSB

We don't recommend or rank companies. Before you hire, check the certification number in the directory yourself and ask for a follow-up test after any system is installed. Questions to ask a radon professional.

04 / HOMEBUYERS

Put radon inside the due-diligence window.

No seller test is required, and the nearest visible certified provider may need to travel more than 60 miles.

A new home is not automatically radon-ready.

Neither published code path requires a passive radon system. Ask the builder whether a gas-permeable layer, sealed penetrations and a vent pipe were installed voluntarily—then test the finished home.

Lexington issued roughly 16–21 new single-family permits a year from 2021 through 2025, while the Census county estimate was 25 building permits in 2025. Those are construction-context figures, not evidence that any homes were tested or built radon-ready. [12] [13]

Transaction plan

  1. Write radon into the inspection or due-diligence plan.
  2. Book early; certified providers appear to travel into the county.
  3. For a new build, ask for plans and photos of any passive radon features.
  4. If mitigation is installed, retest to verify performance.
05 / TESTING RESOURCES

Start with Tennessee’s radon program.

A do-it-yourself kit can screen a home. For a time-sensitive purchase or sale, compare nationally certified providers and confirm service area first.

TDEC homeowner testing

Tennessee’s Radon Program offers free test kits for homeowners and technical information for schools, real-estate professionals, contractors and home inspectors.

Visit Tennessee environmental resources →
Search NRPPUse Lexington ZIP 38351 and confirm measurement credentialsSearch NRSBLook for a Radon Measurement Specialist or TechnicianEPA provider guidanceTest kits and qualified-service resourcesView Tennessee’s dashboardHenderson returned “No Events” when checked
06 / FAQ

Questions Henderson County homeowners ask

Is Henderson County in a high-radon zone?

Henderson County is mapped as Zone 2, the moderate-potential category with predicted average indoor levels from 2 to 4 pCi/L. A zone cannot predict one home, so every home still needs a test.

What does Tennessee’s dashboard show for Henderson County?

Two county-labeled checks returned “No Events” in the combined 2022–2023 view. That means no tests were mapped to Henderson County in this dataset; it does not mean the county has no radon.

Does unincorporated Henderson County require radon-resistant construction?

No. After the October 13, 2026 opt-out motion failed, the county moved into the State Fire Marshal residential program. That rule uses the 2018 IRC plus Appendix Q only, not Appendix F for radon.

Does Lexington require radon-resistant new construction?

Not under the published code. Lexington’s codified Title 12 adopts the 2012 IRC without listing appendices, so Appendix F was not adopted. A city flowchart conflicts on the current edition, so confirm with Lexington Codes.

Are certified radon testers based in Henderson County?

The October 2026 checks found no NRPP- or NRSB-listed measurement professional based in the county. The nearest visible NRPP result was about 62 miles from Lexington.

07 / SOURCES

Primary documents, public data & directories

  1. Lexington Progress: County Approves State Building Codes — October 14, 2026 account of the failed opt-out motion.
  2. Tennessee Rule 0780-02-23 — 2018 IRC residential standard and Appendix Q adoption.
  3. Lexington Municipal Code, Title 12 — 2012 I-code adoption through Ordinance #201802.
  4. EPA Tennessee radon-zone map; county table cross-check at EPA Map of Radon Zones: Tennessee.
  5. Tennessee Radon Testing dashboard — two live county-tooltip checks, October 16, 2026.
  6. NRPP Find a Professional — Lexington and Jackson ZIP searches, October 16, 2026.
  7. NRSB Find a Professional — Lexington and Jackson measurement searches, October 16, 2026.
  8. Lexington new-construction flowchart — city permitting and conflicting 2018-code reference.
  9. Tennessee Code §49-2-121 — voluntary school indoor-air program language.
  10. Tennessee HB1269 — 2018 proposed school radon-testing language.
  11. Tennessee Residential Property Condition Disclosure — radon named among environmental hazards.
  12. Lexington city profile — permit history and city context.
  13. U.S. Census QuickFacts: Henderson County — population, housing and 2025 permit estimate.
  14. MTAS residential code opt-out explainer — Tennessee local/state enforcement framework.
  15. 2025 Tennessee Radon Fact Sheet — state law and transaction context.

Method note. This page separates verified findings from unresolved questions. “No Events” is reported exactly as the Henderson County tooltip displayed it; blank fields were not estimated. Health-region bars are not presented as county statistics, and directory results are dated snapshots rather than a census.