Roaring Brook News
Fall 2003
Demystifying Mold - Part II
ENGINEERING A
BETTER FUTURE
In the last issue we focused our attention on the demystification of mold, mold sampling, and the indoor air analysis of mold. In this issue we will continue our discussion of mold, and in specific, Mold Remediation.
An Introduction to Mold
Molds reproduce by producing tiny spores. Mold spores waft through the indoor and outdoor air continually. When mold spores land on a damp spot indoors, they may begin growing and digesting whatever they are growing on in order to survive. There are molds that can grow on wood, paper, carpet, and foods. When excessive moisture or water accumulates indoors, mold growth will often occur, particularly if the moisture problem remains undiscovered or un-addressed. There is no practical way to eliminate all mold and mold spores indoors; the way to control indoor mold growth is to control moisture.
Mold Sampling
Design of a sampling program is more complex than many people think. At present there are no U.S. Environmental Protection Agency (EPA) or other Federal regulations governing the allowable amounts of mold or mold spores present in buildings. Therefore sampling cannot be used to check a building's compliance with any federal mold standards because there are no standards. Air sampling may, however, be useful to determine if an area has been adequately cleaned or remediated by comparing the mold levels before and after remediation. Sampling can be useful in locating the source of mold contamination, in identifying the species of mold present, and in differentiating between mold and soot or dirt. Types of samples include air samples, surface samples, bulk samples (chunks of carpet, insulation, wallboard, etc.), and water samples taken from condensate drain pans or cooling towers. Note that air sampling reveals what was in the air only at the moment the sample was taken.
Sampling for mold should be conducted by pro-fessionals who have specific experience in designing mold sampling protocols, in sampling methods, and in interpreting results. Sample analysis should follow professional guidelines or analytical methods such as those recommended by the American Industrial Hy-giene Association (AIHA) or the American Confer-ence of Governmental Industrial Hygienists (ACGIH).
Health Risks of Mold Exposure
Health professionals tell us that human health risks are based on the types of mold present, the relative abundance of the types of mold spores present, and the total indoor area of building materials observed to be involved in the growth of mold. They also tell us that some molds are more toxic or allergenic than others are, and that individual reactions to exposure vary. Furthermore, many molds are poorly studied, and little may be known about their potential health effects.