Airborn mold spores land on a food source and when the appropriate conditions are present, the spore produces root like filaments that spread along the surface. As the mold grows it can then release new spores into the air, like seeds, to propagate. It is important to note that mold spores exist naturally and are everywhere in the indoor and outdoor environment. Once the appropriate conditions for mold growth are removed, then molds will go dormant until favorable conditions are re-introduced and they will renew their growth. There is no practical way to eliminate all mold and mold spores in the indoor environment.