How clean does a home need to be for someone with CIRS?

Why there’s no single number

Agencies like the EPA and CDC don’t publish a safe indoor mold level for anyone, let alone for people who are especially sensitive. Their guidance is practical instead: find the moisture, fix it and remove the growth. That leaves a gap for families with CIRS, and the doctors who work with them fill it in different ways. Some focus on one dust test. Others look at several results together. A few set targets for specific rooms, such as the bedroom.

From the building side, that means the question “how clean?” can’t be answered by a remediation company alone. It has to start with whoever is reading the results on the medical side.

Commonly cited guidance

Some numbers come up often in conversations about CIRS homes, and it helps to know where they come from. Commonly cited guidance from Dr. Ritchie Shoemaker’s published work reads HERTSMI-2 scores below 11 as generally acceptable, 11 to 15 as borderline, and above 15 as too high for people sensitive to water-damaged buildings. ERMI results are often discussed too, and our answer on what a good ERMI score is explains why there’s no official passing mark.

These figures are reference points, not rules. Your doctor may use them, set a stricter target, or rely on something else entirely. Whatever they choose is the number that matters for your house. If you’re unsure which test your doctor prefers, ask before anyone collects a sample. Testing twice because the first round used the wrong method costs time and money, and it delays the answers you’re waiting for.

How testing shows progress

Once a target exists, testing turns a vague goal into something you can track. A typical sequence looks like this:

Stage	What’s measured	What it tells you
Baseline	The test your doctor asked for, plus a moisture inspection and often a mycotoxin panel	Where the home starts, and where the problem is
After source work	Moisture readings in the repaired area	Whether the water problem is really fixed
Clearance	The same test as the baseline, in the same locations	Whether the home now meets the agreed target
Later check	A repeat of the same test, if your doctor wants one	Whether the home has stayed where it should

The key is using the same test, the same lab and the same sample locations each time, so the results are comparable. Switching from a dust test at baseline to an air test at clearance, for example, makes it hard to say whether anything changed. Our page on clearance testing describes the options.

What to agree on before any work begins

• Which test will be used to measure the home, and which lab will run it.
• Which rooms will be sampled separately, such as the bedroom of the person who is sick.
• What result your doctor would consider acceptable.
• What happens if clearance doesn’t reach that result: more cleaning, a wider scope, or a new conversation with the doctor.

Put all four in writing and share them with both your doctor and the remediation company. When everyone is measuring the same thing, a result is easy to act on. When they’re not, families end up with a job that passed one test and failed another.

We remove mold and mycotoxins from buildings. We don’t diagnose or treat medical conditions, and nothing on this page is medical advice. The target for your home, and any decision about returning to it, belongs with your doctor. With your permission, we’re glad to share test results and our plan with them.