|
| |
|
|
Real Estate News
You and California
Welcome page
FIRPTA Law
Proposition 90
Chloramine in
Bay Area
Drinking
Water
HVAC Duct Law
Earthquakes
Capital Gains
Property Tax
Exemptions
Contact Joanne |
Frequently Asked Questions About
Mold
By: Dr.
Nathan Yost, MD.
Building Sciences Corporation
What causes mold to
develop?
Mold requires nutrients,
water, oxygen and favorable temperatures to grow. Nutrients
for mold are present in dead organic material such as wood,
paper or fabrics; mold can also derive nutrients from some
synthetic products such as paints and adhesives. Mold requires
moisture, although some mold species can obtain that moisture
from moist air when the relative humidity is above 70 per
cent. Many molds thrive at normal indoor temperatures; few if
any molds are able to grow below 40 F or above 100 F. Outside
this range molds may remain dormant or inactive; they may
begin to grow again when the temperature is more favorable.
Temperatures well above 100 F will kill mold and mold spores,
but the exact temperature required to kill specific species is
not well established.
How does mold get into
a building?
Molds are decomposers of
organic material such as wood, plants and animals. Mold and
mold spores are found in high concentrations wherever there is
dead matter such as a pile of leaves, manure or compost. Mold
spores enter buildings through the air or on people, animals
and objects that are brought into the building. Spores are
small bundles of genetic material and chemicals (similar to
seeds) that molds make under certain
conditions.
Are there harmful and non-harmful
molds?
There are only a few molds that
can cause infection in healthy humans. Some molds cause
infections only in people with compromised immune systems. The
biggest health problem from exposure to mold is allergy and
asthma in susceptible people. There are more than 100,000
types of mold. Good information has been developed for only a
small number of these molds – at least in terms of their
effects on human health. Most people tolerate exposure to
moderate levels of many different molds without any apparent
adverse health effects.
Some molds
produce powerful chemicals called "mycotoxins" that can
produce illness in animals and people. Scientific knowledge
about the health effects of these toxins on humans is quite
limited.
Does mold affect everyone the same
way?
No. Some individuals have a
genetic makeup that puts them at risk for developing allergies
to mold. People who have an allergy to mold, especially if
they also have asthma, can become ill from exposure to a small
amount of mold. Individuals also seem to be quite different in
their response to exposure to the toxic chemicals that some
molds release. These differences between individuals
contribute to the difficult question of determining safe
exposure limits for mold.
How much mold
exposure is harmful?
No one knows the
answer to this question for several reasons. Individuals are
very different with respect to the amount of mold exposure
they can tolerate. Children under the age of one year may be
more susceptible to the effects of some molds than older
individuals. Measuring or estimating "exposure" levels is very
difficult. "Exposure" means the amount of mold (microscopic
spores and mold fragments) that gets into a person usually by
breathing, but also by eating or absorption through the skin.
For example, a building may have a lot of mold in the walls
but very little of that mold is getting into the air stream.
In that case the people working or living in that building
would have little mold exposure.
Can mold
exposure cause brain damage or death?
Although some "experts" claim that individuals have
brain damage or have died because of exposure to mold and
especially mold toxins, there is no good science at this time
to support these claims. Consequently it is prudent to
minimize one's exposure to really moldy environments. By
"really moldy" we mean where there are large visible areas of
mold (more than a few square feet) or the building has a
"musty" odor because of hidden mold growth. There are many
epidemiological studies showing that people who live in houses
with dampness have many more health problems, especially
respiratory, than do people who live in dry houses. This
association does not "prove" that it is the mold that is
responsible for the increase in illness. However, it does
support the assertion that it is not wise to live in damp,
moldy buildings.
Does tighter building
construction promote mold development?
Tighter building construction does not by itself
promote mold growth, but tight construction combined with some
poor choices in design, building materials or operations can
increase the probability of mold growth. What do we mean? The
tighter the building construction the less air exchange there
is between the inside air and the outside air. Whatever gets
into the inside air stays there longer than it would in a
house with loose construction. Moisture that gets into the air
from activities such as cooking, bathing and even breathing
will remain in a tight house longer than it would in a loose
house. That's why exhaust fans should be installed in
bathrooms and kitchens and vented to the outside. Clothes dryers should also
be vented to the outside.
Tight
construction permits control of the air exchange between the
inside and the outside and can prevent the deposition of
moisture in walls and roofs. Controlling moisture, including
indoor relative humidity is the key to preventing mold growth.
Tight building construction when combined with source control
of moisture (exhaust fans) and controlled ventilation
(intentional introduction of outside air) reduces the
probability of mold growth in a building. Controlled
ventilation can be provided by a duct that brings outside air
to the return side of the air handler of a forced air system.
A timing device or fan cycler can be programmed to have the
air handler turn on for a specified number of minutes each
hour even when there is no call for heating or cooling. In
cold climates controlled ventilation is frequently provided by
a heat recovery ventilator (HRV).
Do new
building materials (e.g. drywall or paper faced gypsum board)
promote mold growth?
Mold needs water,
a nutrient source, oxygen and favorable temperature to grow.
Many species of mold love paper faced gypsum board. Why?
Making paper involves the mechanical and chemical processing
of wood. Paper is largely pre-digested so it is easy for mold
to get nutrients from the paper. But unless there is enough
moisture present mold can't grow on the paper. If paper faced
gypsum board is kept dry, it can be used and still not have
mold. This material is kept dry by controlling the interior
relative humidity, keeping rain from entering roofs and walls,
and NOT using paper faced gypsum in areas that are likely to
get wet. This means no
paper faced gypsum board in shower and tub areas. Cement
board, mortar or non-paper faced gypsum can safely be used in
these damp areas because these products do not contain
nutrients to support mold growth.
Are there
reliable tests to indicate the presence of
mold?
Almost all of us already have
two effective mold detectors: our eyes and our noses. If black
or green discoloration is noticed that is fuzzy in appearance
and is in a location that is damp or had been damp, it is
almost certainly mold. If a building smells musty, there
probably is mold somewhere; the mold may be on boxes stored in
a basement or in walls or in the crawl space. If you want to
find mold, look for the presence of water or a location where
water was likely to have been. If there is still any question
about whether the black stuff is mold, have a reliable
laboratory examine the material. All you need to know is
whether mold is seen when the material is examined under the
microscope.
An increasing number
of companies are offering "air testing for mold." On the
surface this seems like a reasonable thing to do. The problem,
however, is that the results of most air sampling for mold are
meaningless for two reasons. Air sampling for mold was not
developed to determine if an environment was safe or had a
dangerous level of mold in the air. Air sampling was developed
to help identify the location of a hidden reservoir of mold.
If the source of mold is already identified, air sampling does
not provide additional meaningful information. Furthermore,
safe or toxic levels of air borne mold have not been
established. An individual air sample for mold provides a
"snapshot" of what was in the air during the few minutes of
sampling. The results may not be indicative of the amount of
mold that is in the air during most of the
day.
Air sampling for mold should
be done either to obtain an answer to a question that cannot
be answered without the air sampling or to obtain data as part
of a research project. The Center for Disease Control (CDC),
the U.S. Environmental Protection Agency (EPA) and the
American Conference of Governmental Industrial Hygienists do
not recommend routine air testing for
mold.
If mold is present, what's the best way
to get rid of it?
The answer depends
on how much mold is present and where it is located. If the
mold is on furnishings or boxes simply discard the materials.
Moldy materials are not considered hazardous waste; they can
be sent to a regular landfill. However, it is smart to seal
the mold material in heavy plastic to protect the people who
handle it in transit and prevent spreading large amounts of
the mold into the building as you carry the material out of
it.
If the mold is on a hard
surface but occupies less than 10 square feet wash the area
with soapy water (scrubbing with a brush may be necessary),
rinse and allow the area to dry before repainting. If you have
asthma, severe allergies and a weaken immune system get
someone else to do the clean up.
Larger areas (greater than 10 square feet in area)
should be cleaned by someone with experience in doing this
type of work. Remember, determine what caused the moisture
problem and correct that problem. Otherwise, mold is likely to
recur.
Is it possible to completely eliminate
mold from the inside of a home or office
building?
The answer depends upon what
is meant by "completely eliminate mold." To keep a building
completely free of mold spores requires very efficient air
filtration and is only accomplished in special situations such
as hospital operating rooms and manufacturing "clean rooms."
Remember, mold spores are in the outside air virtually all the
time and some of them will get inside
buildings.
However, it is possible
to keep mold from growing inside a building. Moisture control
is the key to controlling mold in interior spaces. Air
filtration can contribute to lowering mold spores in the air
but is secondary to moisture control.
Should
I use bleach to get rid of mold?
No.
Although bleach will kill and decolorize mold, it does not
remove mold. Dead mold can still cause allergic reactions. It
is not necessary to kill mold to remove mold. Soap and water
and scrubbing can remove mold from hard surfaces. The
Environmental Protection Agency (EPA), the Center for Disease
Control (CDC) and the New York City Health Department agree
that bleach or other biocides should not routinely be used to
clean up mold.
How do I know when the mold
clean up is finished?
The mold cleanup
is finished when there is no visible mold remaining and there
is no dust or dirt remaining that could contain large amounts
of mold and mold spores. Routine clearance testing for mold is
not necessary. Leaving a few mold spores behind is not a
problem if the underlying moisture problem
has been corrected. Remember that mold
spores are virtually everywhere. Even if all mold and mold
spores are removed as part of the cleanup, spores from outside
will re-enter that space. The spores won't be able to grow
unless water is also present.
Where can I
get more information about mold?
Environmental Protection Agency
Information on
Mold/Moisture/Mildew. Available in HTML and PDF.
Center
for Disease Control
Information on
Mold.
Various topics on mold including information about strains.
About the
Author
Dr. Nathan Yost, MD is a
Principal with the Building Science Corporation, a building
and construction consulting firm. Over the last twenty years,
Dr. Yost has been a home builder, and a medical doctor
specializing in respiratory illness. NAR has hired Dr. Yost on
a contractual basis to provide its members with information
and analysis on the scientific aspects of mold and moisture
issues. The information contained in this FAQ is strictly the
opinion of Dr. Yost, does not reflect NAR policy, and should
not be construed as medical advice.
Reprinted from
National Association of Realtors online update - November 20,
2002
|
Ethical Mold Inspector in the San Francisco
Bay Area
By:
Clayton Barry
There is much misinformation about mold in
today's media. Many people are turning mold into gold by
telling lies, or half-truths and playing off of our fears. In
the modern scientific times in which we live,
black-mold is as feared as yesterday's bogeyman. We
must dispell the myths.
What is the truth about Mold? Who can you trust?
How do you find someone who is ethical to inspect a possible
mold problem?
The fear of mold and the high costs
charged by restoration companies have caused insurance
carriers to cancel policies, raise rates, add no-mold clauses,
or lower clean-up limits. Some insurance companies won't take
on any new home policies in certain mold crazy states.
The situation is out of hand. Our Federal government has not
yet established any mold clean-up standards. The medical world
is still out to lunch on the effects of mold. Is mold harmful
or not?
There are no Federal guidelines
concerning mold contamination levels. There are no proven
medical reports that show mold is deadly to anyone except
persons with advanced HIV, or a few other medical conditions.
There are a few restoration trade associations who are busy
trying to set standards for clean-up. Within the remediation
industry prices for service are coming down. Marketing and
advertising pieces are reflecting a more sensible no-panic
message. The U. S. Environmental Protection Agency (EPA)
offers some advice. They walk the middle of the road with
their overall approach. Its better than nothing, at least the
EPA advises to use eye protection, respirator masks and rubber
gloves when cleaning mold. They indicate that anything under
ten-square feet of mold can be self cleaned, over that they
tell you to consult with an expert restoration company.
an
example of black mold
There are more than 60,000 molds that
have been studied and more than 25,000 have been named. Only a
few produce spores small enough to work their way into our
blood stream. These are the ones that pose a potential threat
to humans. These are the ones that are called toxic
molds. The truth is that these molds are only toxic under
certain circumstances. They are not toxic all the time. What
seems to be agreed upon by all experts is that mold is an
allergen, similar to pollens, or dust mites. Most experts
agree that if you see mold growing in your home, solve the
moisture problem and clean-up the mold. Mold does not need to
be a mysterious frightful or thing.
Before you invite an inspector or a
mold remediator to visit your home there are a number of
questions to ask.
- The first question, "How
dangerous is mold?" If the person starts talking about
serious health risks, life endangering conditions and
doesn't present a more calm and balanced approach, pass this
person up.
- Another question to ask, "What
causes mold in my home?" If the answer is much more
complicated than explaining the cause is ALWAYS excessive
moisture, you have a person who is over complicating
matters.
- Ask this, " Does the moisture
problem need to be solved before mold clean-up is
started?"( There are times when moisture problems and
mold clean-up are addressed at the same time. Usually
moisture should be addressed first.) If the person answering
your question seems really eager to launch into the mold
clean-up work, you may be talking to a "mold is gold hound."
You may want to ask the inspector or
mold remediater to describe their typical report and typical
mold project. Asking for business and client references is
always a smart idea. If he doesn't provide references by all
means pass this person up.
An ethical moisture and mold inspector
will tell you that the majority of molds are not harmful. They
should explain that the few harmful types of mold need to be
present in large amounts to be of concern to persons with
specific health conditions. The molds also need to be
producing mycrotoxins to be considered dangerous. The
honest expert will explain that the source of moisture must be
stopped, otherwise the mold will be back within days or weeks.
THE MOISTURE PROBLEM MUST BE SOLVED. Anyone who downplays the
simple cause of mold and plays on your fears is not truely
interested in helping you.
Any and all service plans for moisture
drying and mold clean-up should be presented in writing with
the prices clearly noted as per-item charges. (The costs of
mold clean-up are coming down in the restoration industry
because the public is becoming aware of the truth about molds.
Mold scams are going away as people learn most molds aren't
harmful. The insurance companies are closing their deep
pockets making it less attractive to work in this arena.)
In the San Francisco Bay
Area an ethical moisture and mold inspector is the author
of this article, Clayton Barry. He can be contacted at:
servpro9332@gmail.com
Note: Joanne recommends Clayton Barry and his Servepro
company as she has done business with Mr. Barry for many
years and consistently finds him to be the best at what
he does!
|
|
Joanne L. Gardiner, Broker, e-PRO
Realtor
"For Old-Fashioned Service
in Cyberspace"
Advantage Realty
Advantage
Mortgage Associates
3205 Whipple Road - Union City,
California 94587
(510)
429-4800
San Francisco Bay
Area
San Francisco East Bay Real
Estate
web site: http://www.joannegardiner.com
Our primary services in the San
Francisco Bay Area are: East bay real
estate, Hayward real estate, Castro Valley
real estate, Danville real estate, Dublin real
estate, Fremont real estate, Newark real
estate, Niles real estate, Pleasanton real
estate, San Leandro real estate, San Lorenzo real
estate, San Ramon real estate, Sunol real
estate and Union City real estate.
The types
of real estate in which we specialize are:
houses, homes, condominiums, townhomes, garden homes, PUDs,
single family homes, manufactured homes, mobile homes, modular
homes, duets, residential income property, duplexes,
tri-plexes, four-plexes, small apartment complexes and
special use properties.
Alameda County Homes,
Homes in Alameda County, Contra Costa County Homes, Homes in
Contra Costa County, Castro Valley Homes, Homes in Castro
Valley, Danville Homes, Homes in Danville, Dublin Homes,
Fremont Homes, Homes in Fremont, Homes in Dublin, Homes in
Hayward, Hayward homes, Newark Homes, Homes in Newark, Oakland
Homes, Homes in Oakland, Pleasanton Homes, Homes in
Pleasanton, San Leandro Homes, Homes in San Leandro, San
Lorenzo Homes, Homes in San Lorenzo, San Ramon Homes, Homes in
San Ramon, Sunol Homes, Homes in Sunol, Union City Homes,
Homes in Union City. San Francisco Realty, San Francisco Bay
Realty, San Francisco Bay Area Realty, Realty in San
Francisco Bay Area, East Bay Realty, Bay Area Realty, homes in
San Francisco bay area, homes in San Francisco East
Bay. |
top of
page | |
|
