What is ERMI testing and do I need it?

Answered by Moe Bedard, founder of Mold Safe Solutions — San Diego's mold-only removal company

Short answer

ERMI is a DNA-based analysis of settled dust that quantifies 36 mold species and produces a relative index for the building. It is useful for chronically ill occupants and for buildings with a long water history, and unnecessary for a straightforward recent leak.

Because dust accumulates over months, ERMI reflects a building's history rather than its condition today, which makes it a poor tool for verifying that a remediation worked — clearance testing does that job.

We also offer mycotoxin, VOC, allergen and bacteria testing when a physician is involved and a whole-environment picture is needed.

Why it matters in San Diego

For most San Diego homes, finding the water source is more useful than an ERMI score.

How we handle it

We start with a free inspection and recommend testing only when it helps.

Signs it's time to call us

  • A doctor asked for it
  • Very sensitive occupants

Mistakes to avoid

  • Using ERMI to find mold locations — it can't

Related questions

What testing do you offer?

Air and swab samples: $195 for 2, $295 for 3, $75 each additional.

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125+ five-star reviews across San Diego County

Verified reviews from homeowners, landlords and property managers on Google and Yelp.

5 out of 5 stars
“We had a great experience working with Mold Safe Solutions to remediate water damage in our home. Everyone they sent on site was polite, friendly, and trustworthy. Micah was the main person on site daily and he was wonderfully communicative and we felt like we…”Read full review
Kirsten D.Seal Beach, CA · August 2026 · Yelp review
5 out of 5 stars
“We had mold in our second story bedroom in the closet, ceiling, and floor due to an air conditioner condensation leak. After doing some research, I chose to contact Mold Safe Solutions. Chase came by the same day to assess the damage and had an estimate ready…”Read full review
Michael L.San Diego, CA · May 2026 · Yelp review
5 out of 5 stars
“I had Mold Safe Solutions out to help assess some water damage that had occurred from a sudden leak. The technician arrived right on time and was extremely courteous and thorough, showing me infrared images of the extent of the water and explaining their proce…”Read full review
Jason WoernerMarch 2026 · Google review
5 out of 5 stars
“Moe and his team at Mold Safe Solutions are the absolute BEST, their level of professionalism and efficiency is hard to find. I will never use anyone else, they came in and fixed the mistakes of another company. I am so grateful I found them!!”
Niki BrownNovember 2025 · Google review
5 out of 5 stars
“Moe's crew did a great job. Inspected our property for mold and let us know what the problem was. Installed a new bathroom fan and cleaned all surfaces in the bathroom and connected bedroom. Very satisfied.”
Mary K S.Carlsbad, CA · January 2026 · Yelp review
5 out of 5 stars
“I can't say enough about this company and Moe the owner. They are the A-Team. They were responsive. They were on time. They were thorough, professional, and nice.”
B PellisJanuary 2026 · Google review
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