Aliso Viejo, CA Radon Levels

Q: What is the average radon level in Aliso Viejo, CA?

Based on 1 user-submitted tests, the average radon level is 5.00 pCi/L.

Q: What EPA Radon Zone is Aliso Viejo in?

Aliso Viejo is in Orange County, EPA Zone 3.

Q: How much does radon mitigation cost in Aliso Viejo?

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

Check local Aliso Viejo radon levels and find certified testing and mitigation professionals to keep your home safe

Aliso Viejo, CA Radon Facts

EPA Radon Zone Zone 3 — Low Risk < 2.0 pCi/L (Zone 3)

County Orange County, CA

Zip Code 92656

Avg. User Level 5.00 pCi/L

User Tests 1

This planned community in Orange County represents master-planned development from the 1980s onward, featuring Mediterranean-style homes predominantly built on slab foundations over marine sedimentary formations. Located in zip code 92656 within the broader Los Angeles metropolitan area, Aliso Viejo's relatively newer construction and slab-on-grade foundations typically result in lower radon accumulation potential. However, testing data for the area remains limited, so homeowners should still consider baseline radon testing to ensure safe indoor air quality.

5.00

pCi/L average

Above EPA Action Level

Based on 1 user-submitted radon test for homes in Aliso Viejo, CA. The EPA recommends taking action at or above 4.0 pCi/L.

4.0 EPA

10+

Aliso Viejo, CA Radon Mitigation

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

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Radon FAQ for Aliso Viejo, CA

What is the average radon level in Aliso Viejo, CA?

Based on 1 user-submitted test, the average radon level in Aliso Viejo is 5.00 pCi/L. This exceeds the EPA's recommended action level of 4.0 pCi/L, and radon testing is recommended for all homes in the area.

What EPA Radon Zone is Aliso Viejo in?

Aliso Viejo and the 92656 zip code are in Orange County, which has an EPA assigned Radon Zone of 3. A zone of 3 predicts an average indoor radon screening level less than 2 pCi/L.

How much does radon mitigation cost in Aliso Viejo?

Radon mitigation in Aliso Viejo 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 Aliso Viejo?

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 in California with the most user-submitted radon test data, ranked by number of submissions.

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
Bishop	6.25 pCi/L	4
Oakland	5.00 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
Sacramento	4.33 pCi/L	3