Mold: What it is and what you need to know
What is mold
Mold is an umbrella term that refers to certain groups of fungi that are known to have the ability to develop into visible colonies on surfaces, varying in color from black to green to white and sometimes fuzzy. Mold spores, which are not visible to the naked eye, are widespread in nature and occur everywhere -- in every cubic inch of air and on every surface, including our skin and food. It is because of mold and fungi that fallen leaves and trees disintegrate into the earth. One type of mold produced a life-saving antibiotic called penicillin. Mold amplification in a building can lead to complaints, allergies, and health problems and should be avoided.
Mold spores are like microscopic seeds that fly on air currents and land on surfaces. In order for a mold spore to germinate, three things must be present:
- a cellulose-based food source, such as paper, wood, leather, organic fabrics, dust, skin flakes, soap residue, etc.
- a suitable temperature
- moisture (water or humidity)
When large areas of mold growth on building materials result from prolonged contact with water, professional remediation should be considered. If you don't see mold but a musty odor is present, this usually indicates the possibility of hidden mold growth or elevated spore levels, and can follow a flood event or prolonged, unchecked, excessive humidity.
Some mold myths and factsA lot has been said about mold in buildings. Some have suggested that "black mold" is toxic and can result in brain damage. Here are some myths and facts to provide perspective about this house and building hot topic.
Myth: Black mold is toxic
Fact: Out of the thousands of known species of mold, only a handful are known to be potentially toxic. And those species will not always develop toxic characteristics -- the correct conditions must be present. Also, mold species cannot be identified visually, only through laboratory testing. If an area of mold growth is black, this does not mean that it is necessarily toxic. It might not even be mold. It is standard procedure for a sample to be taken prior to remediation, as the last thing anyone wants to do is a several-thousand-dollar remediation on something that is not mold. It should also be noted that ungerminated airborne spores themselves can cause allergic reactions, regardless of the species or ability of the spores to germinate.
Myth: Mold grows only on paper, wood, and other cellulose-based material
Fact: It is true that mold needs a cellulose-based food source to develop. But, mold will grow on any surface, including glass, fiberglass and even steel, as long as the surface has a food source on it. Surfaces such as glass and steel can be easily cleaned, whereas materials such as drywall or wood paneling are perishable and would need to be removed if contaminated. The best anti-microbial carpeting can suffer from extensive mold problems if it is loaded with dust and skin flakes.
Myth: Mold can be eliminated
Fact: Unless you need to maintain a clean room, which might be used for surgery or semiconductor development, complete mold elimination is too costly and unnecessary for any home or building, as mold spores are omnipresent in the world. The goal with remediation is to bring mold ecology to normal, ambient levels. The best thing to do is to control moisture and react quickly to flooding or leakage by drying out water-damaged materials. Some types of mold can proliferate is as little as 48 hours.
Myth: Only professionals should clean mold
Fact: Homeowners can clean small patches of mold using household detergents and warm water. It would be ridiculous to hire a professional to clean the surface mold in your shower or refrigerator door. Larger patches of mold may need to be eliminated by trained professionals. Recognized authorities suggest that any damaged area larger than 10 sq. ft. should be handled professionally, but this can vary based upon building use and occupancy -- every situation is unique.
Myth: Mold should be cleaned with bleach
Fact: There are various chemicals that are used by professional remediators and bleach is not one of them. The best thing to use yourself is a detergent soap and water. Bleach is useless on damaged drywall or wood. Porous materials such as drywall cannot be cleaned with anything and generally must be removed, unless the growth is only a mild surface growth on glossy paint, in which case it may well be able to be cleaned.
Myth: It's OK for the mold remediation contractor to conduct their own mold verification tests after the cleanup in complete.
Fact: Town building inspectors verify that builders have built to current building codes. This is called third party verification and protects the public from deficient and dangerous construction practices by unscrupulous or inexperienced contractors. For the same reason, you should hire a separate party to verify that your remediator has done a good job. As of January 2016, it is illegal in New York State for mold remediators to perform their own clearance testing. Testing must be done by an independent 3rd party licensed mold assessor.