Understand Your Mold Test Results
Use this tool for either species-by-species air-sample comparison or ERMI score interpretation. Mold reports do not use a single EPA action number, so context matters.
Indoor vs. Outdoor Air Samples
Enter the counts from your report for the key species below. The main question is whether indoor levels are higher than the outdoor reference by species.
Stachybotrys
Water-damage indicator species
Aspergillus
Compare indoor counts to the outdoor sample
Penicillium
Compare indoor counts to the outdoor sample
Chaetomium
Water-damage indicator species
Cladosporium
Compare indoor counts to the outdoor sample
No Strong Indoor Signal
These air-sample numbers do not show a clear indoor spike relative to outdoor air for the main species entered here.
That does not rule out hidden mold. If you still have odor, staining, or moisture damage, follow the building symptoms rather than the air sample alone.
- •Indoor samples are most reassuring when they are similar to or lower than outdoor levels by species.
- •Cladosporium is often common outdoors, so context matters.
- •If visible growth or active moisture is present, the building still needs remediation even if the air sample looks mild.
What to do with the result
- Air samples are most useful when they are matched with a walkthrough, moisture readings, and visible conditions.
- Any indoor Stachybotrys should be escalated. It is not a species to dismiss as background.
- If remediation is performed, ask for post-remediation verification or clearance testing instead of assuming the job is done.