Zone 1 means test the house, not skip the inspection

EPA Zone 1 is a county prediction, not a bedroom reading. The EPA Map of Radon Zones puts Washington County in Zone 1, the highest band, because the predicted average indoor screening level is greater than 4 pCi/L. Your hallway can still be 1.2. The house next door can still be 9. The map is why buyers in Johnson City still put radon on the inspection list. It is not a pass or fail for this address.

Washington and Sullivan are Zone 1. Carter and Unicoi are not.

Washington County (Johnson City, Jonesborough, Gray, Boones Creek) is Zone 1. Sullivan County (Kingsport and Bristol TN) is Zone 1 too. Carter County and Unicoi County, ten minutes toward the mountains, are Zone 2. You can drive from a Zone 1 ranch in Gray to a Zone 2 crawl in Elizabethton in twenty minutes. Radon does not read the county line.

Zone 2 is a milder predicted average. Individual Zone 2 homes still clear 4. If a listing agent says they skip radon in Elizabethton because the map is yellow, that is a family story, not a measurement.

The geology version of this speech is on the Washington County radon risk explainer. This page is the transaction version: what the map means for a contract.

Tennessee does not require a pre-sale radon test

Tennessee does not mandate radon testing before a sale. Nobody at the courthouse will stop a closing because nobody ran a monitor. Buyers still test here because Washington County is Zone 1, because a continuous monitor fits inside a normal inspection window, and because a surprise 8 pCi/L on day nine is a worse negotiation than a known number.

If you already live in the house, a TDEC kit is a fair first look. If you're buying or selling, use a professional continuous monitor so the other side gets a time-stamped report.

What a contract-grade test looks like

• Closed-house conditions start before the device does, usually about 12 hours. HVAC can run. Whole-house fans and open windows cannot.
• Device in the lowest level that could be lived in.
• A continuous radon monitor (CRM) on site for about 48 hours, plus scheduling.
• A written report with the address, the times, the average, and the protocol notes.

Tell us the inspection deadline. We will say if the calendar works. Do not wait until the last Wednesday on a split-foundation house. The real estate testing page is the how. This page is the why.

What Zone 1 does not do

Zone 1 does not print a pCi/L for your street. We will not invent one from the map, from a tiny pile of user-submitted tests, or from this website's risk tool.

Zone 1 is not an automatic fail. Plenty of Zone 1 houses test under 4. Plenty of Zone 2 houses test over 4. EPA drew the map to target where testing and mitigation programs matter. They still tell you to test every home.

If the test is high, that is a foundation and fan problem, not a geology verdict. The after a failed radon test page is the handoff: confirm, quote, who pays, retest.

Tennessee does not issue a state radon measurement license. Ask for NRPP or NRSB credentials and look them up before you hire anyone for a contract file.

Request a quote with the town, the inspection window, and whether the house is vacant. Call (423) 455-9162. Johnson City Radon. Johnson City, TN.