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
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
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
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
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
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.
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
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
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
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