ERMI and HERTSMI-2: What Dust Testing Can and Cannot Tell You in Arizona
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 Arizona changes about the picture
Hot desert statewide with a summer monsoon season. Flat and low-slope roofs common in the housing stock are vulnerable to monsoon ponding and parapet leaks.
Protocols are national; moisture is local. In Arizona, 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 AZ moisture drivers to read this against
- Monsoon wind-driven rain at roofs and parapets
- Evaporative cooler moisture
- Plumbing leaks drying slowly inside sealed assemblies
What never changes — anywhere
Arizona changes where the risk concentrates — never the order of operations. Moisture gets located, testing characterizes the exposure, the water gets fixed before the mold, remediation runs under verified containment, and an independent third party confirms the result.
The full protocol below covers the national playbook in depth — read it alongside the AZ 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
Arizona questions
Does this protocol change in Arizona?
The sequence never changes — locate moisture, test honestly, fix water before mold, remediate under containment, verify independently. What changes in Arizona is where the moisture pressure comes from: monsoon wind-driven rain at roofs and parapets That determines where instruments go first and which assemblies earn suspicion.
What should Arizona households check first?
Start with the failure modes this housing stock is known for. Flat and low-slope roofs common in the housing stock are vulnerable to monsoon ponding and parapet leaks. A moisture-focused assessment that ignores those patterns is guessing.
Can I get matched with a vetted provider in Arizona?
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 AZ LIBRARY → The Mold Inspection, Done Right: A Homeowner's Field Manual in Arizona