Molds, mushrooms, mildews, and yeasts are all classified as fungi; a kingdom of organisms different from plants and animals. Mold and bacteria are present nearly everywhere in the environment, including the indoor environment. The growth of mold is geometric rather than arithmetic; thus, the term amplification is used to describe mold growth when conditions are favorable and visible mold forms on surfaces. Normal background levels of mold on interior wall surfaces tend to be on the order of <10,000 colony forming units per square inch (CFU/in2) whereas levels on surfaces, when visible mold is present, tend to be on the order of 1,000,000 CFU/in2 or more. Airborne mold levels tend to be much lower, with normal levels on the order of <250 CFU/m3 and active growth levels on the order of >1,000 CFU/m3 and up.
Much debate has occurred regarding the extent to which exposure to mold results in health effects for humans. A National Academy of Sciences study has found sufficient evidence of an association between exposure to damp indoor environments and some respiratory health issues. In addition, epidemiological studies indicate that there is sufficient evidence to conclude that the presence of mold indoors is associated with upper respiratory symptoms, coughing, wheezing, and asthma symptoms in sensitive asthmatic persons.
Our well-experienced industrial hygiene professionals are equipped to sample indoor mold populations using a variety of sampling methods for both airborne and surficial mold growth. Our qualified staff can then analyze and interpret the collected data using current industry guidelines and best practices.
Up to 40% of homes in the United States have mold problems.
Normal background levels of mold on interior wall surfaces tend to be on the order of <10,000 colony forming units per square inch (CFU/in2), whereas levels on surfaces with visible mold present tend to be on the order of 1,000,000 CFU/in2 or more.
The Kingdom Fungi has been estimated at around 1.5 million species, of which only about 5% have been formally classified.
The word mold is derived from the Old Norse language word for “fuzzy”.