
01
The testing problem
Standard mold testing captures a snapshot—a single moment in one location. It often cultures organisms on growth media, identifying only species that can grow in lab conditions. Most of what's actually present (estimates suggest 70 to 85 percent of species) never appears.
The scoring systems that doctors and inspectors use have a structural flaw: they measure mold species against total dust. In homes with heavy dust from pets, foot traffic, or daily life, dangerous species get diluted in the denominator. A dirtier home can receive a better score—not because it's safer, but due to the flawed math.






