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Find Mold & toxic material testers in San Francisco

Avatar for Moisture & Restoration Consultants, LLC
Moisture & Restoration Consultants, LLC
4.8(
59
)

Serving San Francisco, CA and surrounding areas

Approved

In business since 1994

Emergency services offered

Warranties offered

"Mr. Osborn was very prompt in inspecting our water intrusion problems and testing for mold. We received the results of the testing within a short time and he made specific recommendations for correcting all of our issues. We appreciate his help very much."
Mold Remediation Project
Master Bathroom
Master Bathroom
Hall Bathroom
Hall Bathroom

+27

Response time10 hrs
14 neighbors recently requested a quote
Recommended by85%of homeowners
Avatar for Mold Remedies
Mold Remedies
4.4(
30
)

Serving San Francisco, CA and surrounding areas

Approved

In business since 2002

Credit card accepted

Customers say: Super punctual

"These guys were professional, knew exactly where the mold was coming from and how to remove it. They were timely and did a great job!"
Areas of concern
 Dry Rot
Polluted Air
Clean air
We can make it happen

+15

Response time2 days
5 neighbors recently requested a quote
Recommended by95%of homeowners
Avatar for Mold Test Company Central CA
Mold Test Company Central CA
4.0(
88
)

Serving San Francisco, CA and surrounding areas

Approved

In business since 2015

Emergency services offered

Small jobs welcome

"The inspector was professional and thorough. The report was timely and the company's representative called me to explain the results of the test. I've emailed him to request clarifications and am awaiting his reply. The only negative thing is that after our telephone conversation he transferred me to a 3rd party company who markets mold removal services. The rep there tried to sell me his product. I didn't buy it yet."
Attic Ceiling
Drywall
Drywall
Insulation
Insulation

+66

Response time10 hrs
197 neighbors recently requested a quote
Recommended by87%of homeowners
Avatar for Bio 911
Bio 911
4.9(
92
)

Serving San Francisco, CA and surrounding areas

Approved

In business since 2005

Free estimates

Emergency services offered

"Easy and fast communication. Business owner came out quickly per our request, and tested the air quality in an around our home, and did mold testing. He was speedy and kind; very informative of what he was doing and what he would be looking for. Gave us his thoughts and recommendations on what we saw visually, and then put the tests in to the laboratory same day. Results came back within 3 days. I highly recommend them for your mold and air testing needs!"
Mold under window
mold on concrete foundation
after treatment
after remediation
Hoarding cleanup

+18

Response time5 hrs
Response rate98%
1 neighbors recently requested a quote
Avatar for Environmental Science Services
Environmental Science Services
4.5(
42
)

Serving San Francisco, CA and surrounding areas

Approved

In business since 1992

Free estimates

Emergency services offered

"Shane is very professional. I hired ESS because they offered indoor air quality tests for asbestos in addition to bulk sample tests. I also had an airborne mold test since they traveled to Santa Rosa, and the report was very thorough and tested for 27 types of mold spores including Stachybotrys (toxic black mold). I would recommend ESS to a friend seeking this service."
interior
IAQ
Clandestine Laboratory Investigation
Wipe Testing for Asbestos
Water Intrusion Mold Testing

+3

Response time8 hrs
6 neighbors recently requested a quote
Recommended by97%of homeowners
Avatar for Air Quality Testers
Air Quality Testers
4.2(
5
)

Serving San Francisco, CA and surrounding areas

Approved

In business since 2020

Small jobs welcome

Credit card accepted

Breathe Easier with Expert Mold Inspections and Environmental Air Testing. At Air Quality Testers, we specialize in Certified Indoor Air Quality and Mold Testing Services. Our experienced professionals evaluate your air quality, detect mold, and provide personalized solutions. Schedule Your Test Today for a Healthier Home or Office: Tailored Advice and Simple Solutions for Clean Air. We safeguard your space with comprehensive air quality and mold testing, ensuring peace of mind for you and your family.\n\nOur focus is on those concerned about the air quality in their homes or workplaces. We stand out by offering certified indoor air quality testing and mold inspections, thorough air quality assessments, tailored recommendations for improvement, and cutting-edge technology to uncover hidden mold and evaluate air conditions.

Crawlspace hatch
Crawlspace
Storage Room
Response time2 days
Response rate97%
1 neighbors recently requested a quote
Avatar for Bay Area Mold Pros
Bay Area Mold Pros
4.6(
10
)

Serving San Francisco, CA and surrounding areas

In business since 2017

Free estimates

Credit card accepted

"Rick was pretty knowledgeable about mold and the process that creates it and how it should be treated. Took no more than about 30 minutes and he answered all my questions thoroughly. Really appreciate the help."
Response time4 hrs
Recommended by100%of homeowners
Avatar for My Pure Environment Santa Clara
My Pure Environment Santa Clara
4.6(
38
)

Serving San Francisco, CA and surrounding areas

In business since 2010

Free estimates

Warranties offered

"The scheduling, conversation, and discussion with their service manager Steve all went well. They contacted me quickly and had someone out the same day. I was told I would receive a 16-page report, showing detailed explanations and the results of a control outdoor sample and 2 indoor test samples. The tech collected the samples and invoiced me right away, sending photos of the mold areas he inspected as well. He asked me to pay that day which I did, but I now know I should have waited for the report before settling this invoice. Instead of what was discussed during booking, I received a short 3-page report, which showed only the results of the test samples, no control, and no guidance on the result interpretation of the numbers presented. When I contacted the territory rep that did the work to inquire about why control was not done, and why the report seemed so abbreviated, I was told you can do your own tests; or you can schedule another appointment for me to run a new control sample for ~ $200 more. Mind you I had already paid then the ~$400 day of, which was supposed to have included this work. Additionally, in consulting with another lab and my legal advisor, the control sample must be collected on the same day as the others for the most reliable/ valid sampling. so essentially the report I got might be useless at worst, and certainly easily challenged, rendering me having wasted ~$400. I have reached out to their customer service to see if they would be willing to remedy the situation, but have not heard back."
Attic Rafters
Attic Rafters
Our Processes Efficacy
EPA
Fog building up

+3

Response time1 day
Response rate92%
Recommended by88%of homeowners
Avatar for Isaacs Forensic Laboratories
Isaacs Forensic Laboratories
5.0(
6
)

Serving San Francisco, CA and surrounding areas

In business since 2000

Emergency services offered

Small jobs welcome

"I had a great experience with Isaac Forensic. Rafi and team responded quickly in an urgent situation, cleaned and fixed the mold problem the same day and in a short time. I am extremely happy with the service and the knowledge that Rafi demonstrated through the process. Highly professional and realizable. I would definitely recommend them!"
Response time7 hrs
Response rate97%
Showing 1-10 of 45
FAQs for mold & toxic material test projects in San Francisco, CA

Some companies offer a no‑cost phone or video consultation that screens for red flags. If the discussion points to a real issue, the pro will recommend a paid on‑site inspection. The complimentary call clarifies whether you need full testing, but it isn’t a substitute for samples, lab work, or a written report. Always confirm what the free service covers before you schedule.

A standard inspection, which includes basic air and surface samples, takes an average of two hours. If the pro needs to probe hidden spaces, such as wall cavities or ductwork, plan on up to six hours. Extra time allows the inspector to reach tight areas, collect additional samples, and document findings. Lab analysis is a separate process and often adds several business days to the overall timeframe before you receive the full report.

Mold thrives where moisture lingers and air flow is poor. Common hotspots include bathroom walls, kitchen backsplashes, window sills, HVAC vents, fireplaces, crawl spaces, and enclosed attics. Check these areas regularly—especially after leaks or high‑humidity weather—to catch growth early and avoid costly repairs.

Unchecked mold can knock 20% to 37% off a home’s market value because buyers worry about hidden damage and health risks. Even after remediation, visible staining or a history of major moisture issues can still lower offers and prolong the time on the market. Addressing mold quickly protects both your property’s structural integrity and its resale appeal.

The San Francisco, CA homeowners’ guide to mold & toxic material tests

From average costs to expert advice, get all the answers you need to get your job done.