Molds are part of the natural environment. They are microscopic fungi that can be found indoor or outdoors throughout the year. Few have a chemical makeup that can cause allergic reactions in sensitive individuals. Molds play an important role in breaking down organic matter such as fallen leaves or toppled trees. Molds can become a serious problem when they grow inside your home or inside buildings. Molds may grow practically everywhere because they adapt to many environments and reproduce rapidly. Molds grow on wood, paper, carpet, foods, insulation, and a variety of other surfaces. Some molds grow and live on the dust and dirt that gathers in the moist regions of your home. Molds need only a source of food, moisture, and the right temperature to grow.
Description of Mold/Fungi. Molds and other allergens The biological chemicals can arise from a host of means, but there are two common classes: (a) moisture induced growth of mold colonies (b) natural substances released into the air such as animal dander and plant pollen The primary hazard of mold growth, as it relates to indoor air quality, comes from the allergenic properties of the spore cell wall. More serious than most allergenic properties is the ability of mold to trigger episodes in persons that already have asthma, a serious respiratory disease.
Acceptable level of Fungi/Mold
Rao, et al. (1996) recently found that existing quantitative standards and guidelines for total fungi in indoor air range from <100 CFU/m3 to >1000 CFU/m3 as the upper limit for noncontaminated indoor environments, based primarily on baseline data rather than health effects information.