Spores are microscopic reproductive particles, typically ranging from 2 to 100 micrometers in size, functioning much like seeds for mold. Due to their extremely small size and lightweight nature, spores easily become airborne, traveling effortlessly through indoor air currents. When spores land on moist surfaces, they can quickly germinate and establish new mold colonies, often unnoticed until substantial growth has occurred.

In addition to spores, mold fragments—small pieces of the mycelium network—can also become airborne. These fragments often include fine particles (FP) and ultrafine particles (UFP), measuring less than 2.5 micrometers and even smaller than 0.1 micrometers, respectively. Due to their tiny size, these fragments can penetrate deeply into the lungs, posing a greater respiratory risk than larger particles. Their presence often indicates active mold growth or disturbance of existing colonies, such as during cleaning or remediation activities.

While spores and mold fragments naturally occur and are found in virtually all indoor environments, managing humidity and moisture levels within homes is crucial. Keeping indoor humidity below recommended levels, promptly addressing water leaks, and ensuring good ventilation are effective ways to prevent spores and mold fragments from rapidly multiplying and causing widespread mold contamination. Proactive moisture control is essential for protecting indoor air quality and maintaining a healthy living environment.