ERMI and HERTSMI-2: What Dust Testing Can and Cannot Tell You in Minnesota
ERMI and HERTSMI-2 are the dust tests most CIRS-literate physicians reference. This guide explains what they measure, how to collect a sample that means something, how to read the scores, and the honest limitations nobody selling you a kit will mention.
What Minnesota changes about the picture
Severe humid continental with extreme winters. Deep-winter attic condensation — warm indoor air leaking into cold attics — is the state's defining pattern.
Protocols are national; moisture is local. In Minnesota, the pressure a building lives under comes from specific, predictable directions — and this protocol should be read with those directions in mind, because they decide where the risk concentrates, which assemblies fail first, and what a defensible local scope looks like.
The MN moisture drivers to read this against
- Attic frost and condensation from air leakage
- Ice damming
- Spring basement moisture
What never changes — anywhere
The sequence holds in Minnesota exactly as it does everywhere else: locate the moisture, characterize the exposure with testing collected correctly, fix the water before touching the mold, remediate under verified containment, fine-clean, and verify independently. Every shortcut this industry sells is a reordering of that list.
The full protocol below covers the national playbook in depth — read it alongside the MN context above.
Read the full protocol: ERMI and HERTSMI-2: What Dust Testing Can and Cannot Tell You →
- What these tests actually measure
- Why dust beats a single air sample
- Collection determines whether the result means anything
- Reading the numbers without panic
- The honest limitations
- When to retest
Minnesota questions
Does this protocol change in Minnesota?
The sequence never changes — locate moisture, test honestly, fix water before mold, remediate under containment, verify independently. What changes in Minnesota is where the moisture pressure comes from: attic frost and condensation from air leakage That determines where instruments go first and which assemblies earn suspicion.
What should Minnesota households check first?
Start with the failure modes this housing stock is known for. Deep-winter attic condensation — warm indoor air leaking into cold attics — is the state's defining pattern. A moisture-focused assessment that ignores those patterns is guessing.
Can I get matched with a vetted provider in Minnesota?
Yes — matching runs in all 50 states. Every provider is vetted on containment discipline, fine-particle competence, and willingness to be independently verified. Matching is free for households.
THIS PROTOCOL IN OTHER PRIORITY MARKETS → California · Colorado · Florida · Nevada · Texas
NEXT IN THE MN LIBRARY → The Mold Inspection, Done Right: A Homeowner's Field Manual in Minnesota