Excerpts FEMA advisory No. 1493-24 "Hurricane Isabel Carried A Hazardous Potential For Mold" last updated 28-Jun-2005:
According to The Journal of the American Medical Association (JAMA), mold growth in water-damaged homes is a potential hazard from flooding.
Exposure to high spore levels can cause the development of an allergy. Mold can also cause structural damage to your home. Similarly, when wood goes through a period of wetting, then drying, it can eventually warp and cause walls to crack or become structurally weak.
Mold could become a problem in your home if there is enough moisture available to allow mold to thrive and multiply. Dampness in basements, walls, carpets, and wood caused by flooding provide an environment for mold to flourish. You can also be exposed to mold through skin contact and eating.
For some people, a relatively small number of mold spores can cause health problems. The basic rule is, if you can see or smell mold, take steps to eliminate the excess moisture, and to cleanup and remove the mold. It is important to quickly identify and correct any moisture sources before health problems develop. Infants, children, immune compromised patients, pregnant women, individuals with existing respiratory conditions, (allergies, multiple chemical sensitivity, and asthma) and the elderly appear to be at higher risks for adverse health effects from mold.
You can tell if you have mold in your home if you can see it, or if there is an earthy or musty odor. Allergic individuals may experience the symptoms listed above. Visible mold growth is found underneath materials where water has damaged surfaces, or behind walls. Look for discoloration and leaching from plaster.
Before beginning work on a flooded home, make sure the electricity is turned off. Unplug appliances and lamps, remove light bulbs and cover plates of wall switches or outlets that got wet. If local building inspection code allows you to disconnect wiring from switches and outlets, do so and throw them away. If your building inspector says that you cannot disconnect the wiring, pull them forward, away from the wall, and leave them connected.
Never use a gasoline engine indoors - you could expose yourself and your family to carbon monoxide.
If mold odors persist, continue to dry out the area and search for any hidden areas of mold. If the area continues to smell musty, you may have to re-clean the area. Continue to dry and ventilate the area. Don't replace flooring or begin rebuilding until the area has dried completely.
Remover all drywall and porous materials that have been exposed to water. Using a hand-pump or battery-powered garden sprayer, spray a heavy application of BioZap Mold & Mildew Cleaner on all walls and floors. Keep the area enclosed.
BioZap uses essential oils of the Australian Tea Tree, which penetrates into porous surfaces for a lasting effect. It contains no chlorine or bleach, and does not release toxic fumes. It is safer to your health and the environment than chlorine or other bleaches.
Place several jars of BioZap Air Purifier & Deodorizer in the affected areas. Its vapors will attack the invisible molds in the air and in porous surfaces, as well as break down musty odors.
Seal basement concrete with RadonSeal penetrating concrete sealer. It will purge from the pores in concrete dirt and organic matter, which promotes molds. It will stop musty or earthy odors emanating from the concrete or the dirt below. And it will seal the concrete against moisture and deny the mold spores a place to grow. After sealing, wait severaldays and shop-vac the purged dirt.