IN MANY CASES ACTIVE MOLD GROWTH IS NOT VISIBLE AND CAN GO UNDETECTED
Molds are fungi that grow in the form of multicellular filaments called hyphae that spread to form a network or colony called mycelium. There are thousands of known species of molds, although a much smaller number of mold species are commonly found in indoor environments.
Water intrusion and moisture are key elements that cause mold growth. Often these conditions originate from leaky pipes behind walls or under floors, roof leaks, improperly installed windows or excessive humidity. In many cases, these conditions are non-observable - we just don't know they exist.
Whether mold is visible or not, i.e., “hidden mold,” certain chemicals called mold volatile organic compounds (MVOCs) are produced as the mold digests its food. Prolonged exposure to these VOCs can have serious health effects especially in infants, small children, the elderly and anyone with chemical sensitivities or chronic respiratory conditions like asthma or allergies. Because mold VOCs are produced as the mold grows, they can be used as an indicator of active mold.