Mold, one type of fungus, is different from bacteria, plants and animals. These organisms are eukaryotic micro-organisms that are decomposers of dead organic material such as leaves, wood and plants. The spores and hair-like bodies of individual mold colonies are too small for us to see without a microscope. When a lot of mold is growing on a surface, it often appears black, green or blue. The color is determined by the type and is influenced by the nutrient source, surface substrate and the age of the colony.
Mold needs water to grow. Without water, it can not grow. It also needs a food source, oxygen and a temperature between 40 degrees and 100 degrees F. Since mold decomposes dead organic material (cellulose, lignin and hemi-cellulose) it can grow on wood, paper (such as on gypsum board drywall) and other materials made from wood. These type of fungi secrete digestive fluids that decompose the substrate, making nutrients available. They can also digest some synthetic materials such as adhesives, paints and pastes. While mold can not get nutrients from inorganic material such as concrete, glass, metal and plastic, it can grow on the organic dirt/dust layer present on these surfaces. Molds prefer wet or damp material. Some species can get moisture from the air when the air is very damp, that is when the relative humidity is typically above 60 %. The high humidity makes enough moisture available to make surfaces damp enough for mold to grow. We check for damp areas of your home during a mold inspection.
Mold can grow by extension of hyphae that are like tiny root hairs. In this way, a small colony of can expand to cover many square feet of material. Mold can also make spores that are like very small seeds. Spores can survive conditions that are too sunny, hot, cold, dry or wet for mold to grow. When spores are released they can be carried by air or water to new locations. Some spores are so small that they are more affected by air currents than by gravity. When spores land on a damp surface that has food and oxygen available, and if the temperature suits them, they will start to grow. It is important to realize that spores are ubiquitous in nature and are present everywhere, in outside air as well as indoor air– unless very special precautions are taken to remove or kill them such as in cleanroom and hospital operating theaters. Wherever there is decaying organic material (leaves, mulch, and wood) mold and spores are also present. Everyday, since we were born, we have been exposed to airborne spores from outdoor sources, sometimes at high concentrations. It is almost impossible to create a mold-free space or to keep a space mold free. What we can do– and should do– is to control the amount of moisture and hence the amount of mold in our indoor environments. Too much mold can affect the health of you and your family. In addition, fungi can damage or destroy building materials such as the wood or gypsum board in our homes. During our mold testing and mold inspection we will point out areas on concern so that you can correct them.
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