The earliest mention of mold is found in the Bible, in the Book of
Leviticus. Mold is fungi, that helps decay the organic matter around
us. It is attracted to damp, decaying natural materials, containing
cellulose. Some of these are: natural materials, such as paper,
wallpaper, plywood and wood, ceiling tiles, the paper portions of
sheet rock, clothes and leather to mention, but a few. We find mold
and decay in the woods, when we turn over a log or look below the
top layers of fallen leaves, on the ground. Some variety of molds
can be found in all homes, in the United States today. Mold is a
natural part of life.
There are more than 100,000 species of fungi or mold. Two of the
most familiar types of fungi are mushrooms and mold or mildew. Mold
splits, reproduces and releases spores that float through the air.
Mold has been found in the atmosphere at altitudes of 60,000 feet.
If we listen to the weather forecast in the spring, summer and fall,
weather men will give mold spore counts. They are air samples,
gathered to determine the mold allergens that are present in the
air. The spores are seeds that float in the air, and then enter our
homes, when we open a door or window. When a single spore finds the
basic elements that it needs to survive, it reproduces and
The Three Main Classifications of
We use/consume, or are around a bi-product of mold every day. For
instance, mold can be found in beer, wine, cheese, and, most
important, in antibiotics. Mold falls into these three main
- Bread Mold;
- Yeasts, powdery mildew, blue,
green, red, and brown molds, morels and truffles;
- Fungi-mushrooms and toadstools.
Mold can affect us in three ways
The effects of mold on humans depend on their physical receptivity
- Allergenic: In certain people,
contact with mold, either by breathing it, eating it or touching
it, can cause an allergic reaction. Reactions include red eyes,
runny nose, skin rash, hay-fever type symptoms, coughs and fevers.
This may happen whether the mold is dead or alive. Dry mold may
cause as many reactions as active mold.
- Pathogenic: This type of mold is
very harmful. It is defined as an agent that can cause disease and
perhaps kill. It can invade human tissues. Pathogenic mold thrives
in persons with suppressed immune systems or those taking
- Aspergillus Toxic: This type of
mold can produce fatal results, as well. While certain types of
molds are toxigenic, that is, they can produce toxins--mycotoxins,
they, are not toxic, or poisonous, themselves. Like pathogenic
mold, its toxicity depends more on the individual’s immune system.
There are 15 species of Stachbotrys. Stachbotrys mold produces a
mycotoxin. This type of mold is rarely found in homes and represents
a very small percent of the many varieties of mold. Stachbotrys mold
is black and slimy, in appearance, with white edges possibly
present. It needs large amounts of water, high levels of humidity,
cellulose, and low nitrogen levels to survive.
Nine Things You Should Know
- Potential health effects include
allergic reactions, asthma, and other respiratory problems.
- There is no practical way to
eliminate all mold. The way to control the mold is by controlling
the moisture source that the mold needs to grow.
- If mold is a problem; first locate
and eliminate the source of the moisture, then clean up the mold.
- Reduce indoor humidity to between
30 to 60% by: Vent all bathrooms, exhaust fans, clothes dryers,
and other moisture generating sources to the exterior of the
house. Reduce in-door air humidity by using air conditioners and
- Clean and dry all damp or wet
building materials within 24-48 hours to prevent mold growth.
- Clean mold from hard surfaces and
then dry the surface. Absorbent materials like ceiling tiles
should be replaced.
- Prevent condensation on cold
surfaces like windows or cold water supply pipes by insulating the
- In areas of perpetual moisture do
not finish the interior walls or store items that mold may be able
to grow on.
- Molds can be found almost
anywhere. They can grow on virtually any surface where levels of
high humidity, moisture, and a food source are present.
Those at highest risk
Infants, the elderly, immune-compromised individuals, Pregnant
women, and those with respiratory problems are highly at risk.
According to the American Lung Association, between 30 to 50%, or
27.8 million structures, have damp favorable conditions for the mold
growth. Approximately 9.0 million homes (25%) have true mold
When a moisture problem occurs and is not cleaned up and dried out
with in 24-48 hours, there is the possibility of mold growth. In
homes, mold is a symptom of a problem! As an inspector, my job
is to find the source of the problem.
What mold needs to grow and
multiply in homes
- Wet damp conditions caused by
any of the following: Water leaks in the attic, an improperly
vented or unused bathroom exhaust fan, a dripping clothes washer
connection, or leaks in the foundation of the house;
- High Humidity—mold growth will
occur in humidity higher than 55%;
- Temperature--mold growth will
occur when temperatures are above 36 degrees.
- A Feeding Source--mold growth will
occur where there are cellulose containing products, such as
ceiling tiles, newspapers, wallpaper, some paints, plywood,
paneling, particle board. It can be found also in natural fabrics,
leather, glues, draperies and potting soil;
- A surface or place to grow on;
- Limited ventilation.
Note: It takes only one mold spore to create a problem.
Mold Problem Awareness
Today, people are more aware of the problem of mold and concerned
with its effects on their health. This is due to the following:
- The 1973 Oil Embargo resulted in
houses being better insulated and less ventilated. (We move less
- There exist greater technological
advances to identify health problems;
- Improvement in communication has
increased awareness of these issues.
What the inspector needs to detect
As an inspector, I look for the following:
- Visible signs of mold;
- Moldy musty smells;
- Evidence of water penetration
- Something or someplace where a
leak may occur;
- Dirty and poorly maintained Force
Hot Air Heating Systems;
- Improperly vented bathrooms and
To reiterate, mold is a symptom of a
problem. We need to discover what is causing its growth in the home
and eliminate favorable conditions.
Possible Conditions or Locations for Mold to Grow
Favorable conditions or locations for mold to grow are as follows:
- Soil at the exterior foundation,
that is not graded properly;
- Improperly maintained roof,
flashings, or gutter system;
- Leaks, damaged areas below sinks
- Improperly maintained or operating
- Leaks behind clothes washer and
- Bathrooms under sinks and around
- Areas behind refrigerators;
- Crawl spaces.
Mold releases more spores when it is disturbed. When cleaning
surfaces the spore counts are typically 10 to 1,000 times higher
than undisturbed mold.
Most problems experienced in cleaning mold, come from the bleaches
used and not wearing proper protection. If mold gets on the clothes,
it is merely transferred from one surface location to another. What
follows are some preventive measures to clean mold and eliminate its
- Wear gloves;
- Mix 10% household bleach and
- Avoid excessive amounts of runoff
and standing bleach.
If it exists in less than a 10 feet square, the contact mold
sample should be performed with a cotton swab. The following
measures should be taken:
- Each separate area should be
- If there are distinct or different
types of mold, examine each growth
In sampling the air, the following procedures should be observed:
- A trap, to rely on spores falling
directly onto a sampling medium;
- Air Impaction, to suck air samples
into a canister;
- Take samples of indoor and outdoor
A vacuum sample of spores in the carpet should be taken as well.
- Collect spores in the carpet pile
It is important to remember that mold
growth is the byproduct of proper conditions. It is vital to
eliminate the original source or the mold will return.
Additional information about Mold provided by the United States Environmental