Best Radon Testing in Los Angeles, CA
Compare 17 local radon testing providers in Los Angeles. Verified listings with real contact info.
17 services listed
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KNIGHT ENVIRONMENTAL CONSULTING of Beverly Hills - Mold Testing and Inspection
8383 Wilshire Blvd Suite 800, Unit 10, BEVERLY Hills
Monday: Open 24 hours | Tuesday: Open 24 hours | Wednesday: Open 24 hours | Thursday: Open 24 hours | Friday: Open 24 hours | Saturday: Open 24 hours | Sunday: Open 24 hours
4.8 ★
47 reviews
Environmental One
1739 Del Valle Ave, Glendale, CA 91208
Monday: 9:00 AM – 5:00 PM | Tuesday: 9:00 AM – 5:00 PM | Wednesday: 9:00 AM – 5:00 PM | Thursday: 9:00 AM – 5:00 PM | Friday: 9:00 AM – 5:00 PM | Saturday: Closed | Sunday: Closed
5 ★
28 reviews
Andersen Integrated Services
10020 National Blvd UNIT B, Los Angeles, CA 90034
Monday: 8:30 AM – 6:00 PM | Tuesday: 8:30 AM – 6:00 PM | Wednesday: 8:30 AM – 6:00 PM | Thursday: 8:30 AM – 6:00 PM | Friday: 8:30 AM – 5:00 PM | Saturday: Closed | Sunday: Closed
5 ★
28 reviews
PropertyHealth, Inc.
2263 Fox Hills Dr, Los Angeles, CA 90064
Monday: 7:00 AM – 6:00 PM | Tuesday: 7:00 AM – 6:00 PM | Wednesday: 7:00 AM – 6:00 PM | Thursday: 7:00 AM – 6:00 PM | Friday: 7:00 AM – 4:00 PM | Saturday: 10:00 AM – 2:00 PM | Sunday: Closed
5 ★
20 reviews
Crystal View Home Inspectors
20 Kerwood Ave, Los Angeles, CA 90067
Monday: 9:00 AM – 6:00 PM | Tuesday: 9:00 AM – 6:00 PM | Wednesday: 9:00 AM – 6:00 PM | Thursday: 9:00 AM – 6:00 PM | Friday: 9:00 AM – 6:00 PM | Saturday: 9:00 AM – 6:00 PM | Sunday: Closed
5 ★
14 reviews
Andersen Environmental
5261 W Imperial Hwy, Los Angeles, CA 90045
Monday: 9:00 AM – 6:00 PM | Tuesday: 9:00 AM – 6:00 PM | Wednesday: 9:00 AM – 6:00 PM | Thursday: 9:00 AM – 6:00 PM | Friday: 9:00 AM – 6:00 PM | Saturday: Closed | Sunday: Closed
4 ★
2 reviews
JLM Environmental
Address:, 11150 W Olympic Blvd Ste. 1050 #1121, LOS Angeles
Monday: 8:00 AM – 5:00 PM | Tuesday: 8:00 AM – 5:00 PM | Wednesday: 8:00 AM – 5:00 PM | Thursday: 8:00 AM – 5:00 PM | Friday: 8:00 AM – 5:00 PM | Saturday: 8:00 AM – 4:00 PM | Sunday: Closed
5 ★
22 reviews
Environmental Inspection Services
1311 Marine St, Santa Monica, CA 90405
Monday: 9:00 AM – 6:00 PM | Tuesday: 9:00 AM – 6:00 PM | Wednesday: 9:00 AM – 6:00 PM | Thursday: 9:00 AM – 6:00 PM | Friday: 9:00 AM – 6:00 PM | Saturday: Closed | Sunday: Closed
5 ★
1 reviews
Blue Line Home Inspections, LLC
240 26th St Unit B, Santa Monica, CA 90402
Monday: 9:00 AM – 5:00 PM | Tuesday: 9:00 AM – 5:00 PM | Wednesday: 9:00 AM – 5:00 PM | Thursday: 9:00 AM – 5:00 PM | Friday: 9:00 AM – 5:00 PM | Saturday: 8:00 AM – 12:00 PM | Sunday: Closed
4.8 ★
40 reviews
Clark Seif Clark, Inc. (CSC)
4010 Watson Plaza Dr Suite 170, Lakewood, CA 90712
Monday: Open 24 hours | Tuesday: Open 24 hours | Wednesday: Open 24 hours | Thursday: Open 24 hours | Friday: Open 24 hours | Saturday: Open 24 hours | Sunday: Open 24 hours
5 ★
4 reviews
West Coast Environmental Testing
11024 Balboa Blvd Suite 757, Granada Hills, CA 91344
Monday: 8:00 AM – 8:00 PM | Tuesday: 8:00 AM – 8:00 PM | Wednesday: 8:00 AM – 8:00 PM | Thursday: 8:00 AM – 8:00 PM | Friday: 8:00 AM – 8:00 PM | Saturday: 8:00 AM – 8:00 PM | Sunday: 8:00 AM – 8:00 PM
5 ★
3 reviews
Radon Mitigation Corp. of America
6207 Lochvale Dr, Rancho Palos Verdes, CA 90275
Elite Group Inspection Professionals
21700 Copley Dr #390, Diamond Bar, CA 91765
Monday: 5:00 AM – 7:00 PM | Tuesday: 5:00 AM – 7:00 PM | Wednesday: 5:00 AM – 7:00 PM | Thursday: 5:00 AM – 7:00 PM | Friday: 5:00 AM – 7:00 PM | Saturday: 6:00 AM – 5:00 PM | Sunday: 8:00 AM – 2:00 PM
4.8 ★
2282 reviews
Clark Seif Clark, Inc. (CSC)
21732 Devonshire St #2, Chatsworth, CA 91311
4.9 ★
22 reviews
The Phase One Group
324 S Diamond Bar Blvd UNIT 130, Diamond Bar, CA 91765
Monday: 8:00 AM – 5:00 PM | Tuesday: 8:00 AM – 5:00 PM | Wednesday: 8:00 AM – 5:00 PM | Thursday: 8:00 AM – 5:00 PM | Friday: 8:00 AM – 5:00 PM | Saturday: Closed | Sunday: Closed
5 ★
18 reviews
A-Tech Consulting, Inc.
1640 N Batavia St, Orange, CA 92867
Monday: 7:30 AM – 5:30 PM | Tuesday: 7:30 AM – 5:30 PM | Wednesday: 7:30 AM – 5:30 PM | Thursday: 7:30 AM – 5:30 PM | Friday: 7:30 AM – 5:30 PM | Saturday: Closed | Sunday: Closed
4.8 ★
38 reviews
Affordable Home Inspection Inc.
16787 Beach Blvd #342, Huntington Beach, CA 92647
Monday: 8:00 AM – 6:00 PM | Tuesday: 8:00 AM – 6:00 PM | Wednesday: 8:00 AM – 6:00 PM | Thursday: 8:00 AM – 6:00 PM | Friday: 8:00 AM – 6:00 PM | Saturday: 8:00 AM – 6:00 PM | Sunday: Closed
4.1 ★
23 reviews
Frequently Asked Questions
How much does radon testing cost in California?
Professional radon testing typically costs $175 to $350. Short-term tests (48-96 hours) are used for real estate transactions. Long-term tests (90+ days) provide the most accurate annual average. **CDPH** recommends professional testing over DIY kits for real estate transactions, though DIY kits ($20-$40) are available at hardware stores.
Why is radon especially concerning in California?
California has varying radon levels depending on geology. **Granitic foothill counties and other radon-prone geologic zones** have elevated radon risk due to bedrock composition. Even other areas of the state have measurable radon. **CDPH** considers it a public health issue and publishes county-level radon data.
Are radon testers required to be certified in California?
California does not maintain a single statewide radon tester license like some trades. **CDPH** and professional organizations like the National Radon Proficiency Program (NRPP) or National Radon Safety Board (NRSB) recommend certified testers. For real estate transactions, use a certified professional to ensure legally defensible results.
What happens if my California home has high radon levels?
If radon levels exceed 4 pCi/L, the EPA and **CDPH** recommend installing a radon mitigation system. Sub-slab depressurization is the most effective method and typically costs $1,000 to $2,000. NRPP- or NRSB-certified mitigation contractors can perform installation. Mitigation reduces levels by up to 99%.
When should I test for radon in my California home?
**CDPH** recommends testing all homes, especially in high-risk areas. Test when buying or selling, after major renovations affecting the foundation, or if you have never tested. Testing during cooler months (November through March) with windows closed provides the most representative results. Re-test every 2 years or after major changes to the home.