South Pasadena, CA Radon Mitigation and Testing

Q: What EPA Radon Zone is South Pasadena in?

South Pasadena is in Los Angeles County, EPA Zone 2.

Q: How much does radon mitigation cost in South Pasadena?

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

Los Angeles County

EPA Zone 2

Positioned in Los Angeles County within the Los Angeles Metro area (zip code 91030), South Pasadena sits on alluvial deposits in the San Gabriel Valley where radon levels are typically moderate to low. The community features predominantly older California bungalows and mid-century homes, many with slab-on-grade foundations and minimal basement space. While testing data is currently limited and the geology suggests lower risk, homeowners should still conduct radon testing as individual properties can vary significantly.

South Pasadena, CA Radon Mitigation

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

South Pasadena, CA Radon Testing

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

South Pasadena Radon Facts

Key details about the radon risk profile for South Pasadena and the 91030 zip code area.

EPA Radon Zone

Zone 2 — Moderate Risk

County

Los Angeles County, CA

Zip Code

91030

Predicted Screening Level

2–4 pCi/L (Zone 2)

South Pasadena and the 91030 zip code are located in Los Angeles 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 South Pasadena, CA

What EPA Radon Zone is South Pasadena in?

South Pasadena and the 91030 zip code are in Los Angeles 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 South Pasadena?

Radon mitigation in South Pasadena 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 South Pasadena?

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 California

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

City	Avg User Radon Level	Submissions
Los Angeles	7.83 pCi/L	6
Mammoth Lakes	10.80 pCi/L	5
San Jose	4.20 pCi/L	5
Rancho Palos Verdes	8.00 pCi/L	4
Woodland Hills	7.67 pCi/L	3
South Lake Tahoe	6.33 pCi/L	3
Palos Verdes Peninsula	6.00 pCi/L	3
Bishop	5.67 pCi/L	3
Sacramento	4.33 pCi/L	3
Oakland	3.33 pCi/L	3
Fresno	10.00 pCi/L	2
Davis	8.00 pCi/L	2
Palo Alto	6.50 pCi/L	2
Studio City	6.50 pCi/L	2
Menlo Park	5.00 pCi/L	2
Truckee	5.00 pCi/L	2
Walnut Creek	4.00 pCi/L	2
San Diego	3.50 pCi/L	2
San Francisco	3.50 pCi/L	2
Belmont	20.00 pCi/L	1