Mold testing for CIRS and mold-sensitive households

Testing a home for mold illness, explained

The building questions behind each test

Doctors order home tests for their own reasons, and those reasons are theirs to explain. What we can explain is what each test tells you about the building, so you know what you’re paying for.

Test	What gets sampled	The building question it answers
ERMI	Settled dust	How does this home’s mix of 36 molds compare with homes nationally?
HERTSMI-2	Settled dust	How much of the five molds most tied to water-damaged buildings is in the dust?
Mycotoxin panel	Settled dust or surfaces	Which mold toxins are present, and roughly how much?
Air sampling	Indoor and outdoor air	What’s airborne right now, and is one room different from the rest?
Moisture inspection	Walls, floors, ceilings, HVAC	Where is the water coming from?

Some physicians also ask for dust testing for bacteria-related markers, such as actinomycetes or endotoxins. If yours does, tell us when you book so we can confirm the lab and method before the visit. For a closer look at the two main dust tests, see ERMI vs. HERTSMI-2.

Getting the target in writing

The most useful thing you can bring to a testing appointment is a short note from your doctor: which tests, which score or result they’d consider acceptable, and any rooms they want sampled on their own. It prevents the most common and expensive mistake we see, which is paying for a test your doctor doesn’t use, or for a result nobody can compare with the next one. If the target changes later, we update the plan.

How sampling changes for a sensitive household

• Bedrooms get their own samples. People spend more hours there than anywhere else, so we avoid folding them into a whole-house average when the doctor wants detail.
• The HVAC system is part of the test. A contaminated air handler reaches every room, so the coil, drain pan and returns are inspected on every visit.
• Collection is documented for repeat testing. We record exactly where and how dust was collected, so a retest months later can be done the same way.
• The house is sampled as it’s lived in. No special cleaning beforehand, windows closed, heating or cooling running normally.

Testing a home you’re thinking of moving into

Families who’ve decided to move often want to test the next home before signing. That’s reasonable, with two cautions. A home prepared for sale or turned over between renters may have been cleaned, painted or re-carpeted, which can erase the dust history a test depends on. And an inspection for moisture matters as much as the test score, because a clean result in a house with an active leak won’t stay clean. Our guide to moving without bringing mold with you covers the belongings side of a move.

Retesting after remediation

After remediation, clearance testing confirms the work area before containment comes down. Many doctors also want a follow-up dust test once the family has been living in the home again. For that comparison to mean anything, the retest should use the same lab, the same method and the same rooms as the original. We set that up at the start, not at the end. See mold clearance testing for how the first check works.

Where our role ends

We measure the building, find the source and report what we find. We don’t interpret results medically, recommend treatment, or decide whether it’s right for someone to return to a home. Those decisions belong to you and your doctor. With your permission, we’ll give your doctor everything we have about the house.

We test and remediate buildings. We don’t diagnose or treat medical conditions, and home test results aren’t a medical diagnosis. Nothing on this page is medical advice. Please make health decisions, including whether and when to return to a home, with your doctor. With your permission, we’re glad to share test results with them.