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Aerial neighborhood view in California

Radon Pros in California

42 contractors

EPA zone context: California has a mix of all three zones. The northern Sierra Nevada foothills and some southern inland areas are Zone 1. Coastal regions are mostly Zone 2-3.

MR

MG Remediation, Inc.

4.9 (96 Google reviews)

Certified Professional

Licensed Provider: Ryan J Mandel

Full Service•San Leandro, CA
MitigationTestingCommercial
Certified RMS/RMPFree Estimates
View Profile5102933009
AC

AAA Certified Radon Testing

Certified Professional

Licensed Provider: Steve Zivolich

Sebastopol, CA
TestingCommercialPost-Test
Certified RMP

AAA Certified Radon Testing is a dedicated radon services company serving Sebastopol, CA. Services include radon testing, radon measurement. Works with basements. Methods include heat recovery ventilation, passive radon systems. Holds Certified Radon Measurement Professional certification. Offers real estate transaction testing.

View Profile7072392601
Data provided by Google Maps

State Info

Radon levels vary house-to-house even in the same city. Testing your own home is the only reliable way to know your risk.

Radon mitigation cost in CaliforniaRadon testing cost in California

Popular Cities for Radon Mitigation in California

Radon mitigation in Santa Barbara, California4 local contractors listedRadon mitigation in Irvine, California3 local contractors listedRadon mitigation in Los Angeles, California3 local contractors listedRadon mitigation in Glendale, California2 local contractors listedRadon mitigation in Oakland, California2 local contractors listedRadon mitigation in San Luis Obispo, California2 local contractors listedRadon mitigation in Santa Monica, California2 local contractors listedRadon mitigation in Thousand Oaks, California2 local contractors listedRadon mitigation in Altadena, California1 local contractors listedRadon mitigation in Auburn, California1 local contractors listedRadon mitigation in Burlingame, California1 local contractors listedRadon mitigation in Chico, California1 local contractors listedRadon mitigation in Clayton, California1 local contractors listedRadon mitigation in Cudahy, California1 local contractors listedRadon mitigation in El Dorado Hills, California1 local contractors listedRadon mitigation in Hayward, California1 local contractors listedRadon mitigation in Heritage Ranch, California1 local contractors listedRadon mitigation in La Jolla, California1 local contractors listedRadon mitigation in Long Beach, California1 local contractors listedRadon mitigation in Marina, California1 local contractors listedRadon mitigation in Monterey, California1 local contractors listedRadon mitigation in North Hollywood, California1 local contractors listedRadon mitigation in Pasadena, California1 local contractors listedRadon mitigation in San Leandro, California1 local contractors listed

FAQ: Radon Mitigation in California

Is radon a problem in California?

It depends on location. Coastal areas are generally low risk, but the foothill communities, parts of Santa Barbara County, and the inland valleys can test above the EPA action level.

How much does radon mitigation cost in California?

Most homeowners in California see mitigation quotes in the low-thousands, but the final cost depends on foundation type, fan location, and pipe routing complexity. A cost calculator can help you benchmark estimates before requesting bids.

Do I need radon testing in California before hiring a contractor?

Yes. A valid short-term or long-term test is the fastest way to confirm if mitigation is needed and to scope the right system design.

What radon level is dangerous in California?

EPA recommends action at 4.0 pCi/L, and many homeowners choose to reduce levels even below that threshold. California has a mix of all three zones. The northern Sierra Nevada foothills and some southern inland areas are Zone 1. Coastal regions are mostly Zone 2-3. ZIP-level lookup tools are useful for local context, but home testing is still required.

How do I choose a certified radon contractor in California?

Look for current NRPP or NRSB credentials, ask for post-mitigation test expectations, and confirm local compliance details. California doesn't have state-specific radon certification requirements, but NRPP/NRSB certification is recommended.

State Resources for California

Radon mitigation cost in California

Estimate likely project pricing by foundation type and system complexity.

Radon testing guide for California homes

Learn when and how to test, plus how to interpret pCi/L results.

Radon levels and EPA zones in California

See how state-level risk varies and what zone maps can and cannot tell you.

ZIP-level radon risk in California

Check projected local risk by ZIP code before you request quotes.