CONFIRMED
EPA Zone 2
Zone 2 means moderate radon potential, with a predicted average indoor level between 2 and 4 pCi/L. The zone is a planning tool, not a home test: neighboring houses can measure differently. [10]
01 / QUICK READ
Test the home. The county map cannot answer for it.
Stewart County has a verified information gap—not a verified low-radon finding.
EPA classifies the county as Zone 2. Tennessee’s testing dashboard showed blank average, median, and maximum fields for Stewart County on two full loads, which places it in the dashboard’s “No Events” category for 2022–2023. [6]
Bottom line
A short-term test is the practical first step for owners, buyers, and sellers—especially because local code does not guarantee radon-resistant features.
A short-term test is the practical first step for owners, buyers, and sellers—especially because local code does not guarantee radon-resistant features.
Zone 2EPA moderate-potential designation; predicted average indoor levels of 2–4 pCi/L. [10]
No EventsStewart County’s 2022–2023 dashboard tooltip showed no average, median, or maximum. [6]
0 localNRPP-listed measurement professionals based in Stewart County; directory listings are not a census. [7]
02 / RISK & DATA
What the public data says—and what it cannot say
WITHHELD
No county figures published here
State test figures that couldn't be confirmed on repeat checks aren't shown here. A missing figure doesn't mean radon is absent; test your home to know its level.
Important dashboard caveat
The pre- and post-mitigation charts are health-region aggregates, not county counts. Selecting Stewart County did not turn those charts into Stewart County data, so regional totals must not be presented as local test counts.
03 / BUILDING CODES
Radon-resistant construction is optional across the county
CITY OF DOVER
2018 IRC, Appendix G only
Dover adopted the 2018 International Residential Code through Ordinance #455-21 in October 2021. Its code includes only Appendix G and deletes residential sprinkler provisions. In the 2018 IRC, radon control methods are in Appendix F—so that appendix was not adopted. [1] [5]
Result: radon-resistant new construction is optional, not mandatory, within Dover.
UNINCORPORATED STEWART COUNTY
No local residential code found
Stewart County is absent from the State Fire Marshal’s list of places where a state residential permit is required and does not enforce a local residential code. The evidence points to a county opt-out from the state program. [3] [4]
Result: no county code requirement for radon-resistant new construction was found.
Open verification
The county opt-out resolution number and date were not located online. Confirm with the Stewart County Clerk or County Mayor’s office at (931) 232-3100. Dover’s code currency can be confirmed with Building & Codes at (931) 232-5907. [2]
How do I find a certified radon professional in Stewart 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.
04 / TAKE ACTION
Radon testing resources
Start with a free Tennessee test kit
TDEC’s statewide radon program offers free home test kits and says radon has been detected in every Tennessee county. [11]
1-800-232-1139More ways to get help
- Buy a kit: 1-800-SOS-RADON (1-800-767-7236)
- Live radon questions: 1-800-55RADON (1-800-557-2366)
- Fix-It Hotline: 1-800-644-6999
- Find certified pros: NRPP 800-269-4174 · NRSB 866-329-3474
- Free learning: American Lung Association’s Radon Basics course
Test the lowest lived-in level
Follow the kit instructions and closed-house conditions. A short-term test is a practical screening step.
Read the number in context
EPA recommends taking action at 4 pCi/L and considering action between 2 and 4 pCi/L.
Ask about the foundation
For new construction, ask the builder what voluntary radon-resistant features were installed; local code does not guarantee them.
05 / HOME BUYERS
Make the radon question part of the transaction
Disclosure is not a test
Tennessee’s standard Residential Property Condition Disclosure asks whether the seller knows of radon gas. That is a knowledge question, not a duty to test. Buyers should make their own test part of inspection due diligence. [13]
Existing homes dominate
Stewart County issued 18 building permits in 2025. With 6,801 housing units and limited new construction, most transactions involve existing homes built without a local radon-feature mandate. [12]
06 / FAQ
Questions Stewart County homeowners ask
Is Stewart County in a high-radon zone?
EPA mapping places Stewart County in Zone 2, a moderate-potential zone with a predicted average indoor level of 2–4 pCi/L. That does not predict a particular home’s result. Testing is the only way to know.
Why are no county average or maximum numbers shown?
State test figures that couldn't be confirmed on repeat checks aren't shown here. A missing figure doesn't mean radon is absent; test your home to know its level.
Does a new Dover home have radon-resistant features?
Not necessarily. Dover adopted the 2018 IRC with Appendix G only. The radon appendix for that edition is Appendix F, which was not adopted. Ask the builder which voluntary radon-resistant features, if any, were installed—and still test the finished home.
Are schools required to test for radon in Tennessee?
No statewide radon-testing mandate for schools was confirmed. Tennessee law encourages indoor-air-quality inspection programs, while an introduced bill for explicit school radon testing could not be confirmed as enacted.
How often should a home be tested?
Test after major renovations or changes to the lowest occupied level, and retest periodically. If the home has a mitigation system, retest at least every 2 years.
07 / SOURCES
Primary documents and live directories
- Dover Municipal Code, Title 12 — 2018 IRC, Ordinance #455-21, Appendix G.
- City of Dover Codes, Planning & Zoning — city-only enforcement and contact.
- Tennessee State Fire Marshal: Residential Permits — program scope and opt-out framework.
- Apply for a Residential Permit — official jurisdiction list.
- 2018 IRC Appendix F: Radon Control Methods.
- Tennessee Radon Testing dashboard — live tooltip checks on two loads, October 16, 2026.
- NRPP professional search near 37058 — verified October 16, 2026.
- NRSB professional search — verified October 16, 2026.
- MTAS Statewide Building Standards — state-adopted editions and optional provisions.
- EPA Map of Radon Zones — zone definitions.
- TDEC Radon Program — free kits and statewide resources.
- U.S. Census QuickFacts: Stewart County — population, housing, value, and permit data.
- Tennessee Residential Property Condition Disclosure, RF201 — radon question.