General information from public guidance and local sources. Inspections are performed by independent contractors.How these guides are researched
Short answer: ERMI measures DNA from 36 mold species in settled dust and produces a score; HERTSMI-2 uses five water-damage-associated species. They reflect longer-term buildup, not a single moment. They don't locate the moisture source, and they aren't a standard for judging whether a home is safe. A good inspector pairs them with an inspection so the result leads somewhere.
What ERMI and HERTSMI-2 measure
- ERMI (Environmental Relative Moldiness Index) was developed by EPA researchers for research use. It compares 26 water-damage-associated species with 10 common outdoor species, using a lab method called quantitative PCR, and produces a single score.
- HERTSMI-2 uses five species strongly associated with water-damaged buildings and produces a simpler score. Some physicians use it to help judge whether a home is suitable for a sensitive patient.
Both rely on dust collected in a defined way, usually by vacuuming specific areas into a special filter cassette, or with a cloth swab of undisturbed surfaces.
What these tests can't do
- EPA has said ERMI was developed as a research tool and isn't validated for routine use by the public to judge a home.
- They don't tell you where the mold is or what's causing it.
- Dust can include old contamination from past problems that are already fixed, or spores carried in from elsewhere.
- Scores need context: the house, its history and what an inspection shows.
That's why it helps to pair dust tests with a moisture inspection. Booking ERMI Testing in Nampa, ID alongside an inspection means so a high score comes with a likely source and a plan.
When a dust test makes sense
- Your physician has requested an ERMI or HERTSMI-2 for a specific patient
- You're deciding whether a home is suitable for a mold-sensitive household member, with your doctor's guidance
- You want a longer-term picture alongside air samples
- After remediation, when your doctor wants to compare before and after
For most other questions, such as a musty smell, a home purchase or a leak, an inspection with air samples is more useful. See types of mold tests.
Cost of ERMI and HERTSMI-2 testing
Cost depends on the home, access and the samples needed, and is set by the independent contractor; ask for a written quote. Lab fees vary by lab and turnaround, and DNA analysis often takes longer than spore trap results. Adding a dust test to an inspection is common. Ask for a written quote before the visit. What affects cost.
For families with health concerns, see mold testing for families. Questions about dust testing for a specific patient are best discussed with the ordering physician.
ERMI Testing Nampa, ID: questions
Which is better, ERMI or HERTSMI-2?
Neither is better in general. Use whichever your physician requests. HERTSMI-2 is narrower and often cheaper; ERMI reports more species.
Can I collect the dust myself?
Mail-in kits exist. Professional collection follows a consistent method and comes with an inspection that explains the result. If your doctor is fine with a home kit, it can be a lower-cost option.
What ERMI score is bad?
Scores are interpreted on ranges from the research data, and physicians who use them often have their own thresholds. A score on its own doesn't tell you what to fix; the inspection does. A good ERMI Testing Nampa, ID report includes that context.
Is ERMI Testing in Nampa, ID required for my doctor's program?
Some physician-led programs ask for it. Bring their instructions when you book so the inspector collects the sample the way they want.
