Allergy Partners provides tips about mold in your home or work place and what would be considered reasonable or excessive amounts that could be dangerous to your health. Molds are part of the natural environment, and can be found everywhere, indoors and outdoors. Outdoor molds play a part in nature by breaking down dead organic matter such as fallen leaves and dead trees. Molds are usually not a problem indoors, unless mold spores land on a wet or damp spot and begin growing. Indoors, mold growth should be avoided.