Dayton, WA Radon Mitigation and Testing

Q: What EPA Radon Zone is Dayton in?

Dayton is in Columbia County, EPA Zone 2.

Q: How much does radon mitigation cost in Dayton?

Radon mitigation typically costs between $800 and $2,000. Most standard systems fall in the $1,000-$1,500 range.

Columbia County

EPA Zone 2

Located in rural Columbia County in southeastern Washington, Dayton sits within the Columbia River basalt region where volcanic bedrock generally produces moderate radon levels. Testing data remains limited for this small agricultural community, making professional radon testing important for homeowners. The area's mix of older homes with full basements and newer construction warrants individual assessment for radon exposure.

Dayton, WA Radon Mitigation

Professional radon mitigation is the most effective way to permanently lower radon levels and protect your household.

Dayton, WA Radon Testing

Finding qualified radon testing professionals is the first step toward protecting your home.

Dayton Radon Facts

Key details about the radon risk profile for Dayton and the 99328 zip code area.

EPA Radon Zone

Zone 2 — Moderate Risk

County

Columbia County, WA

Zip Code

99328

Predicted Screening Level

2–4 pCi/L (Zone 2)

Dayton and the 99328 zip code are located in Columbia County, which has an EPA assigned Radon Zone of 2. A radon zone of 2 predicts an average indoor radon screening level between 2 and 4 pCi/L. The EPA recommends testing every home regardless of zone classification.

Radon FAQ for Dayton, WA

What EPA Radon Zone is Dayton in?

Dayton and the 99328 zip code are in Columbia County, which has an EPA assigned Radon Zone of 2. A zone of 2 predicts an average indoor radon screening level between 2 and 4 pCi/L.

How much does radon mitigation cost in Dayton?

Radon mitigation in Dayton typically costs between $800 and $2,000. Most homes with standard basements can be mitigated with a sub-slab depressurization system in the $1,000–$1,500 range. Factors that can increase cost include complex foundations, crawl spaces, or very high radon levels.

Should I test for radon if I'm buying a home in Dayton?

Yes. Radon testing should be part of every home purchase. A short-term radon test is typically included as part of the home inspection process and costs $150–$250. If elevated levels are found, you can negotiate mitigation as part of the sale.

Most Active Radon Markets in Washington

Cities with the most user-submitted radon test data in the state.

City	Avg User Radon Level	Submissions
Vancouver	6.56 pCi/L	9
Kent	3.60 pCi/L	5
Seattle	5.25 pCi/L	4
Olympia	5.00 pCi/L	4
Bellevue	3.75 pCi/L	4
Spokane	11.67 pCi/L	3
Camas	8.00 pCi/L	3
Centralia	7.00 pCi/L	3
Bellingham	4.50 pCi/L	2
Kirkland	4.50 pCi/L	2
Washougal	8.00 pCi/L	1
Ridgefield	5.00 pCi/L	1
Moses Lake	No submissions	0