|
What is Mold, Mildew, and Bacteria?
Mold, mildew, and bacteria are all biological pollutants.
Some of these elements are in every home. It is impossible
to rid your home of all of them. Your goal should be to
recognize the causes and signs of these pollutants and to
minimize or eliminate their entry or stay in your home.
All of us are exposed to these biological pollutants.
However, their effects on our health depend upon the
type and amount of the pollutants present. Some people
do not experience any adverse health reactions from
certain pollutants while others may react moderately or
worse from the same exposure. Individuals at both ends
of the age spectrum (the elderly and newborn) or with
compromised immune systems or respiratory problems are
more vulnerable.
Before we look into ways of controlling these biological
pollutants, let’s look at what we are dealing with. Mold and
mildew are one-cell plant-like organisms that are of the
Kingdom Fungi —
microorganisms that lack chlorophyll and
vascular tissue. This Kingdom includes the yeasts, molds,
mildew, and mushrooms. There are differences between
mold and mildew, but the concerns are similar.
Mold grows from spores which are everywhere in our
environment. Usually these spores are inactive, but will
germinate when the relative humidity exceeds 70 percent.
Mold attacks organic materials such as paper, books,
cloth, photographs, and leather. Mildew is more a surface
concern, growing on walls, siding, and other surfaces
covered with a film of dirt containing organic matter that
has been exposed to moisture. Temperatures above 65°F
(18°C) increase the likelihood of mold or mildew. Signs
of mold and mildew include growths, discolored surfaces
and odors. Homes exposed to flooding, water penetration
or leakage problems, and/or high humidity conditions are
especially susceptible.
Bacteria, another microorganism, can contaminate an air
conditioning system or other moisture-laden areas. Bacterial
growths account for most of the slime that clogs air
conditioner drain pans and drain lines. Bacteria create the
initial tacky coating on heat transfer surfaces that catch and
hold dust and fibers, which can eventually lead to clogged
coil passages.
There are no simple, inexpensive methods of uncovering
fungi or bacteria conditions in a home. But once a biological
pollution condition is discovered, there are means to identify
its cause and to eliminate it. Certain catastrophic events,
such as flooding or serious water intrusion, are certain to
quickly lead to mold conditions unless prompt remedial
action is initiated.
A home inspection does not include a specific investigation
or identification of any environmental concerns including
mold, mildew and bacteria. If there are concerns about
the presence of molds, particularly if related to personal
health factors, a qualified environmental specialist should be
consulted for information on available inspection services.
This information is provided for general guidance purposes only. Neither HMA Franchise Systems, Inc. nor the local
HouseMaster® franchise warrants its accuracy and assumes no liability related to its use. Contact the local franchise
office and/or qualified specialists for advice pertinent to your specific house or circumstances.
© Copyright HMA 2004. Each HouseMaster franchise is an independently owned and operated business.
HouseMaster is a registered trademark of HMA Franchise Systems, Inc.
Fungi and bacteria require moisture to survive. To minimize the chances of your home becoming a breeding ground for any
fungus or bacterium, you must address conditions that contribute to water penetration and high humidity conditions. Here
are some general recommendations to control moisture and help prevent the growth of fungi or other biological pollutants:
• Humidifiers (particularly reservoir, non-misting types) can promote mold and mildew growth and help spread
spores throughout the house if not properly maintained. These units must be serviced regularly.
• Condensate collection pans under the indoor coil for air conditioning units provide a perfect environment
for bacteria. Check and, if accessible, thoroughly bleach-clean them as needed.
• Ground water that is not directed away from your home may penetrate the foundation and/or the crawlspace
walls and will provide mold and mildew spores with the moisture they require to thrive. Pipe downspouts
away from the house, maintain a positive grade around your foundation, and address any water penetration
conditions immediately.
• Faulty or missing flashings allow rainwater to enter your home and settle in hidden areas such as attics and
insulated roof or wall cavities. Check and maintain flashings annually.
• Unfinished, dirt-floor crawlspaces allow ground moisture to rise and permeate house framing and insulation.
Such crawlspace surfaces should be sealed by placing polyethylene sheeting over them and taping all seams
and edges. Keep crawlspaces well ventilated.
• Bathrooms and laundry areas, particularly if unventilated or poorly ventilated, encourage the growth of mold
and mildew. Venting (including bathroom exhaust vents as well as dryer vents) should be piped to the outside
and not to an interior area such as an attic or garage.
• Improperly vented fuel-burning appliances can raise the relative humidity in a room. Shut off offending
appliances at first signs of condensation on windows or other surfaces and check venting systems to ensure
all potentially harmful flue gas exhausts to the exterior.
• Dehumidifiers and air conditioning can be used, especially in hot, humid areas, to draw moisture out of the air.
Be sure these appliances don’t themselves become sources of biological pollutants.
• Major systems, such as furnaces, heat pumps and central air conditioners, should be inspected and cleaned
annually before seasonal use.
• Before using duct cleaning services, confirm there is a need and verify that the contractor will provide
protection from dislodged pollutants and chemicals used in the cleaning process. | 
