ERMI and HERTSMI-2: What Dust Testing Can and Cannot Tell You in Illinois
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 Illinois changes about the picture
Humid continental with cold winters and humid summers. Basement-dominant stock; summer condensation on cool foundation walls behind finished basement framing is the leading hidden pattern.
Protocols are national; moisture is local. In Illinois, 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 IL moisture drivers to read this against
- Basement seepage and summer basement condensation
- Ice damming
- Freeze-thaw plumbing failures
What never changes — anywhere
Nothing about Illinois exempts a project from the sequence: moisture located first, exposure characterized with valid testing, water fixed before mold, containment verified during remediation, fine cleaning completed, and independent verification before anyone declares victory.
The full protocol below covers the national playbook in depth — read it alongside the IL 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
Illinois questions
Does this protocol change in Illinois?
The sequence never changes — locate moisture, test honestly, fix water before mold, remediate under containment, verify independently. What changes in Illinois is where the moisture pressure comes from: basement seepage and summer basement condensation That determines where instruments go first and which assemblies earn suspicion.
What should Illinois households check first?
Start with the failure modes this housing stock is known for. Basement-dominant stock; summer condensation on cool foundation walls behind finished basement framing is the leading hidden pattern. A moisture-focused assessment that ignores those patterns is guessing.
Can I get matched with a vetted provider in Illinois?
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 IL LIBRARY → The Mold Inspection, Done Right: A Homeowner's Field Manual in Illinois