§01
Report header. What to verify first
Every EMSL spore-trap report starts with header data: lab job number (EMSL internal identifier), date received, date analyzed, AIHA-EMLAP lab accreditation number (typically Lab #102344 for EMSL's Buffalo/Cinnaminson location), analyst name + signature, and chain-of-custody reference. The first integrity check is matching the field chain-of-custody serial numbers against the report's sample identifiers. If these don't match, the report has a custody gap and is potentially impeachable.
§02
Sample-by-sample data. The species table
The core of the report is a table listing each sample with detected mold genera/species and quantitative concentrations in spores per cubic meter (sec/m³). The genera most frequently appearing in WNY + PA reports: Aspergillus/Penicillium (commonly reported together as 'Asp/Pen' due to similar morphology), Cladosporium, Stachybotrys, Chaetomium, Curvularia, Alternaria, Basidiospores, Ascospores. Each genus has a different typical-outdoor baseline range and different growth-condition implications.
§03
Indoor-outdoor ratio analysis
The most important diagnostic interpretation is the indoor-outdoor (I/O) ratio for each genus. Outdoor air is the natural baseline. If indoor Cladosporium is 4,200 sec/m³ and outdoor Cladosporium is 4,800 sec/m³, the indoor air is in equilibrium with outside. Not problematic. If indoor Cladosporium is 4,200 sec/m³ and outdoor is 320 sec/m³, the indoor space has an internal Cladosporium source. Always cross-reference indoor sample results against the same-day outdoor baseline.
§04
Stachybotrys and Chaetomium. Special weight
Stachybotrys chartarum and Chaetomium globosum require sustained moisture above 90% relative humidity for 7-14+ days to colonize. Their presence in indoor air at ANY detectable level (even 80-200 sec/m³) where outdoor baseline is 0 indicates an indoor moisture source. These two species carry disproportionate weight in interpretation because their growth requirements rule out 'tracked-in-from-outside' explanations.
§05
Common interpretation pitfalls
Three common pitfalls. (1) Looking only at indoor numbers without outdoor baseline. Meaningless without the I/O ratio. (2) Equating high Aspergillus/Penicillium with mold growth. These are everywhere outdoors and can come from soil, garden, kitchen compost; only an I/O ratio above 2-3x suggests an indoor source. (3) Ignoring spore-trap limitations. Air sampling captures airborne spores only; it can MISS hidden wall-cavity mold growth that hasn't released spores into room air. A negative spore-trap result does not definitively rule out hidden growth.
