The highest potential category: predicted average indoor screening levels above 4 pCi/L. A zone does not clear an address.
Monroe County radon · Tennessee
Monroe County, TN radon Zone 1. No verified radon mandate.
Monroe County has the EPA's highest radon-potential designation, but no local jurisdiction was confirmed to require radon-resistant new construction. The practical rule is to test every home—including new builds.
Tellico Lake image: East TN Vacations
Radon in Monroe County, Tennessee: quick answers
EPA zone: Zone 1Region: East TennesseeState test data: State test figures confirmed on repeat checks
Is radon a problem in Monroe County, Tennessee?
Yes, it can be. Monroe County is in EPA Zone 1, the highest radon-potential category, where the predicted average indoor screening level is above 4 pCi/L. Levels vary from house to house, so a test is the only way to know your home's level.
Do new homes in Monroe County, TN have to be built radon-resistant?
No confirmed requirement. Tellico Plains follows the state code without the radon appendix, Madisonville's 2012 code very likely omits it, and Sweetwater's appendix list isn't published. Local code details
How do I test my home for radon in Monroe 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 Monroe 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 Monroe County from nearby cities. How to choose a radon professional
Sweetwater remains an open appendix question; no other jurisdiction reviewed carries a radon requirement.
NRPP and NRSB searches found zero measurement professionals based in Monroe County.
01 / Building codes
Four jurisdictions, no confirmed radon rule
“Built to code” means different things in Sweetwater, Madisonville, Tellico Plains, and unincorporated Monroe County. None was verified to require the IRC radon appendix.
City enforcement
Sweetwater
Codes Enforcement Officer
2018 I-Codes
Adopting ordinance not verified
Appendix F status is unknown. The city's planning page names the 2018 codes but publishes no appendix list.
City enforcement
Madisonville
County seat
2012 IRC
Ord. #17-251-O · amended #18-268-O
Very likely no Appendix F. The rendered adoption text lists no appendices, but the full section was not reviewed end to end.
State enforcement
Tellico Plains
Local Title 12 is reserved
2018 IRC + IECC
SFMO state-permit program
No radon appendix. State rules exclude optional and appendix provisions from the minimum code.
Permit law only
Unincorporated Monroe County
County Codes Enforcement
No code adoption found
Private Acts of 1965 Ch. 82
Outside the SFMO residential program and likely opted out. The opt-out resolution itself was not found online.
02 / Risk & evidence
A modest average can still hide a high home
The Tennessee dashboard showed a 2.0 pCi/L Monroe County average and a 9.1 maximum. The sample size is unknown, the median did not render, and every value comes from one workbook.
Dashboard average2.0pCi/L · 2022–2023
Dashboard maximum9.1pCi/L · 2022–2023
0 pCi/L9.1 pCi/L
The tooltip said “County: Monroe” and returned the same average and maximum on two separate page loads. The median label appeared without a value. Treat these as limited, single-source context—not a prediction for any neighborhood or home. Open the state dashboard.
What the dashboard does not establish
It does not publish a Monroe County test count or percentage above 4 pCi/L. Its pre- and post-mitigation bands show East Tennessee health-region aggregates, not county totals, and selecting Monroe could not be confirmed to filter those charts.
No Monroe-specific radon rule was found
Repeated searches found no county or municipal radon rule for public buildings, schools, or real-estate transactions. That is a negative research finding—not proof that no non-digitized policy exists. Statewide disclosure rules still require known radon hazards to be disclosed in covered residential sales, while school testing is encouraged rather than required.
How do I find a certified radon professional in Monroe 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.
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.
03 / Homebuyer guide
Test the finished house—not the promise
Growth around Tellico Lake is adding homes in a Zone 1 county where radon-resistant construction was not verified as mandatory. A permit, disclosure, or passive pipe is not a test result.
A practical due-diligence sequence
- Write a radon contingency into the offer. A seller must disclose known hazards in covered transactions, but “no known radon” does not mean the property was tested.
- Name the code jurisdiction. The mailing address may not tell you whether Sweetwater, Madisonville, Tellico Plains, county, or TRDA rules apply.
- Request construction evidence. For a new home, ask for the appendix list, permit records, vent route, slab or crawlspace details, and fan-ready provision.
- Retest after mitigation. Confirm the installed system's performance with a post-mitigation measurement.
Which office issued the permit?Pin down the actual code jurisdiction before asking about appendices.
Was the radon appendix adopted?Ask for the appendix list, not only the IRC edition.
Was a passive system installed?Look for the collection layer, sealed penetrations, and vent path.
Was the finished home tested?Construction details do not establish the indoor concentration.
Is the system fan-ready?A passive system may need activation if testing is elevated.
Can the seller provide the report?Keep test results, system diagrams, and mitigation documents together.
04 / Quick answers
What the records establish
Clear answers where the documents are clear—and explicit limits where they are not.
Is Monroe County a high-radon area?
Yes. EPA classifies Monroe County as Zone 1, its highest-potential category. The designation predicts broad potential; it is not a measurement for a specific home.
Does Sweetwater require radon-resistant construction?
The city says it uses the 2018 I-Codes, but its adopting ordinance and appendix list were not available in the records reviewed. Appendix F's status remains unverified.
What about Madisonville and Tellico Plains?
Madisonville adopted the 2012 IRC, and the rendered adoption text lists no appendix chapters; Appendix F is very likely not adopted, but the full section was not reviewed end to end. Tellico Plains has no local building code and uses the state permit program, whose minimum code excludes optional appendix provisions.
What about unincorporated Monroe County?
The county has a permit law, but no building-code adoption was found. It is absent from the State Fire Marshal's list of counties under state residential enforcement and likely opted out; the opt-out resolution itself was not found online.
What did the state dashboard show?
The Monroe tooltip showed a 2.0 pCi/L average and 9.1 maximum on two loads. The median label rendered without a value. The sample size is unknown, and the band charts are regional aggregates.