What is Mold?

Mold is everywhere. There are more than 100,000 species of mold in the world and at least 1,000 common species are found in the United States. Some molds are beneficial. such as those used to make cheese and medicines. Some however can cause serious illness and, in some cases, even death.

Growing mold produces tiny spores in order to reproduce. The mold then ejects the spores which will float through the air looking for a suitable place to begin new growth. All mold needs to get started is suitable material with a surface moisture content of about 20%. This level of moisture can be achieved by simply surrounding wood with air at 90% relative humidity at any temperature between 40 to 100 degrees Fahrenheit. When mold spores land on a suitable damp spot they will begin to grow and digest the host material to survive. In this respect, mold is considered to be a wood destroying organism.

Common places for mold growth in homes include bathrooms, kitchens, laundry rooms, basements and crawl spaces, air conditioning ductwork and equipment, and concealed places between walls and floors. Mold can basically be found anywhere where the moisture level permits its growth.

Exposure and Health Risk.

When materials that are moldy become damaged or disturbed,, large numbers of spores can be released into the air. You can be exposed to mold by inhaling these spores, by handling the moldy materials, or by accidental ingestion.

Molds can produce a variety of chemicals called mycatoxins. These chemicals are used by the molds as a defense mechanism against other molds or organisms that compete for living space or are otherwise threatening. Mycotoxins from molds can be very dangerous in high concentrations and have even been used in the past to produce military nerve gas. Fortunately, the types of molds that are routinely encountered in low concentration are not particularly hazardous to healthy people. Exposure in higher concentrations however can represent a health threat.

The severity of symptoms depends on the amount of exposure and the individual’s particular vulnerability. Infants and children, elderly, persons with respiratory problems, and compromised immune systems, are most vulnerable. Some of the conditions that have been associated with mold exposure include memory loss, nose bleeds, allergy, cold and flu-like symptoms, eye irritation, coughs, wheezing, difficulty in breathing, sinus and nasal congestion, skin irritation, head aches, and a variety of infections both mild and serious.

Aspergillus, Penicillium, and Stachybotrys.

These three families of molds tend to get the most recognition whenever mold is mentioned in relation to contamination problems in the home. Each of the families contain numerous strains and collectively they represent several hundred species, many of which are potentially harmful.

The stachybotrys family is debatably the nastiest of the three and its various strains are often associated with the above mentioned health problems. Stachybotrys, like many types of mold, is greenish black and typically grows on materials with a high cellulose content that are chronically wet.

There are numerous cellulose containing materials used in home building, everything from drywall to insulation to wood and paper products. Chronic moisture can be caused by everything from high humidity to plumbing leaks to unintended water penetration.

Preventing mold growth in the home.

There is no practical way to eliminate all mold and mold spores in the indoor environment. The object is to control indoor mold growth and this can only be done by controlling moisture. If there are no suitable areas present in the home for mold to grow and flourish, then mold contamination will not be a problem.

The old adage that “and ounce of prevention is worth a pound of cure” truly applies in the case of indoor mold contamination. In order to enact prevention, the home must be properly inspected for the potential of mold growth. Any and all potential problems found must be eliminated. If conditions conducive to mold growth are found to exist, further investigation to determine if mold has indeed begun to grow is warranted.

Getting rid of mold.

Any located mold can be sampled and analyzed by a testing laboratory to identify the exact species. If mold growth is rampant, it is important to know what type of mold you are dealing with. Sampling and laboratory testing is the only way to find out. How the cleanup is conducted (and who should be doing the cleanup) is dictated by the type of mold involved.

Some molds can be safely cleaned away by the homeowner. Small areas of mold on surfaces are best cleaned away using an appropriate household cleaner or a 10% bleach to water solution. If your are already having medical symptoms that might be associated with mold, its best to get someone else to do the cleaning. Always use gloves and dispose of rags and sponges that where used during the cleaning process. Make sure to thoroughly dry the area.

For large areas of growth, or for mold in enclosed spaces such as between walls or in ductwork, you will need to consult a professional abatement of remediation company. Make sure you use a qualified company who knows how to deal with the problem correctly. Unqualified personnel can actually spread the mold spores to every nook and cranny of the house and can contaminate the entire structure and its contents.

Whenever mold is found growing it is important to find the underlying reasons for its appearance so that corrections can be made. Without making corrections to the underlying cause, the mold is sure to return. This may mean patching a leaky roof, correcting points of penetration in exterior siding, repairing plumbing leaks, or getting better control over humidity in the building.

Severe mold problems can be expensive to correct and there have been extreme cases where it was more cost effective to demolish the building than make all the needed corrections.

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