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News Articles
Measure Humidity Level to Avoid Dry Skin, Respiratory Irritations and Excess Moisture Problems
Care Required in Closets and Storage Areas to Prevent Mold Growth
Control Mold Growth in the Bathroom
Everyday Activities Produce Moisture in the Home
Carbon Monoxide Detectors Save Lives
Musty Basements Could Be a Sign of Mold
Test for Radon to Limit Cancer Risk
Humidifiers may Spew Bacteria and Fungi in the Air
Attic Ventilation is Often Overlooked
All
Air Filters Are Not Created Equal
Measure
Humidity Level to Avoid Dry Skin, Respiratory Irritations and Excess Moisture
Problems
Incidents
of respiratory infections and allergic rhinitis, dry and cracking skin, static
electricity and damage to furniture and musical instruments are all may be
caused by low humidity levels. Too much moisture causes damage to a home and may
affect health due to growth of molds and other biological contaminants.
That’s
why experts recommend you test the level of humidity in your home. The
recommended humidity level during the winter months is 30 to 40 percent. A
relative humidity above about 40 percent increases the potential for
condensation on windows and other cool surfaces. Humidity levels below about 30
percent lead to dry skin and nasal passages. During the summer, indoor humidity
levels should be kept below 65 percent to minimize the potential for mold growth
and below 50 percent to minimize dust mites.
The
amount of moisture in the air can be measured using a hygrometer, available at
most hardware stores. These sell for from $5 to $25. One thing to keep in mind
when using a hygrometer is that they are not always accurate. Mechanical
hygrometers are frequently in error by more than 20 percent. Calibrate your
hygrometer by sealing it in a plastic bag along with a cup containing 1/2 cup of
water and 1/4 cup of table salt. Leave it sit for about 12 hours at room
temperature. The meter should read about 75 percent relative humidity. Electronic meters tend to be more accurate, but they should
also be calibrated.
Care
Required in Closets and Storage Areas to Prevent Mold Growth
Fall is
here and it’s time to roll up the summer gear and store it for the winter. But
before tossing everything--the tent, sleeping bags, swimming suits, etc.-- in
the closet, think about your storage area. A musty closet means musty and
damaged property for next year. That’s enough to spoil next year’s summer
fun. But there are some things
Before placing items in the closet, check for dampness in the storage area. Also, check for any spots (moldy areas) in the closet, especially in the corners or on the baseboard. If there are spots, it might be a sign there is mold damage in your home. Basements frequently are damp during the summer. Closets can be conducive to mold growth, especially those on exterior walls. The relative humidity of the air in a closet may be at a level conducive to mold growth, even when the humidity in the house is low, if the temperature in the closet is cooler than in the house during the winter. This will typically occur near the outside wall. Keep the closet warm by storing things away from the outside wall to allow air circulation. Leave closet doors open during very cold weather.
Stored
clothes should be clean and dry. Boxed articles will stay wet if
Control
Mold Growth in the Bathroom
Spots
on the shower curtain or walls of your shower may indicate you have a mold
problem. Mold grows in warm, humid, places such as bathrooms. Soap scum and skin
cells collect on surfaces in a shower and are food for mold and mildew. But
there are some things you can do: Provide ventilation such as exhaust fans in
bathroom and use them when bathing or showering. Run the bathroom exhaust fan
during, and for a few minutes after, showers to exhaust the moisture. A timer
switch is an easy way to make sure your fan stays on for the desired length. You
should be able to feel air entering
Everyday
Activities Produce Moisture in the Home
A
little bit of condensation is normal in the fall, but if it persists, you could
have a problem.
It’s
easy to see why many houses contain too much moisture. Many activities in the
home produce moisture that needs to be removed by ventilation. For example, each
person produces about three pints of water per day while breathing. About one
pint of moisture is introduced into a home during a 10-minute shower, and with
teenagers in the house, this can be more. Additional moisture is added when
towels are drying.
A house will produce six to 16 pints of moisture per day as materials in it dry during the fall. Moisture coming through a concrete basement floor and walls due to moist soil on the outside may create as much as 100 pints per day.
So, what is the easiest way to remove the extra moisture from your home? Ventilation. When outside temperatures are cool, use ventilation such as running bathroom exhaust fans and opening windows. When outside temperatures are warm and humid, use a dehumidifier or air conditioning to reduce moisture in your home.
Carbon
Monoxide Detectors Save Lives
On your
next trip to the local hardware store, be sure to pick up at least one carbon
monoxide detector.
Carbon
monoxide gas, which is produced during combustion, is odorless and colorless,
and can build up quickly in a tight, closed space. This means that you won’t
be able to smell this poisonous gas or detect it with normal senses, making it
fatal if not detected.
A
malfunctioning furnace in your home can be a danger to you and your family
without a carbon monoxide detector. Even if your source of heat is vented, the
air should be monitored against equipment failure.
Have furnaces, regardless of the age, serviced regularly to protect your
family. It is a good idea to have a
furnace technician conduct combustion and heat exchanger leak tests
Unvented
space heaters may sometimes be used as an emergency heat source. However,
remember that the by products of combustion, including many pollutant chemicals
and carbon monoxide, will be released into the air you are breathing. If the
heated is not ventilated, then the area heated should be adequately ventilated.
Unvented space heaters are the main cause of carbon monoxide build-up in
icehouses, so consider a carbon monoxide detector for fish houses too.
Ice dams
look like an ice ridge along the edge of the roof. They indicate that your house
is leaking heat and does not have adequate attic ventilation. It’s important
to look for these spots because water behind the ice may enter the house causing
insulation to be ineffective, leading to the rotting of structural wood,
staining wall coverings and creating conditions conducive for mold growth.
Ice
dams occur when escaping heat melts the snow on the roof and the water freezes
when it reaches the cooler surface near the eaves.
The best way to reduce the potential for ice dams is by providing
adequate attic insulation and ventilation that keep the roof cold and to
minimize any air leaks from the living space into the attic.
The
snow on your house should look like it does on an unheated, detached garage
-with only a little melt around the edges. You do not want bare spots. That
means there is warm air leaking from the living area that warms the roof,
triggering an ice-dam.
Eliminate
Condensation on Windows
Water
and ice buildup on the inside of windows can cause damage to your house, as well
as promote mold growth on the windows structure and frame. Excessive
condensation or frost accumulation on windows may be one sign of too much indoor
moisture or a cold window.
To
prevent this condensation, you can warm the window’s surface by covering the
window with plastic. You will also want to lower the humidity in the home to
under 40 percent in the winter. These two things should greatly reduce
condensation in the home.
Dehumidifiers
generally lower the humidity level to only about 50 percent, so they are not
adequate for limiting condensation during the winter. To help lower humidity
levels, shut off humidifiers. Install and use outside air exhaust fans when
cooking and run fans during baths and showers. These will help reduce unwanted
moisture in your home,
But,
remember that low humidity (below 30 percent) can lead to dry skin
Musty
Basements Could Be a Sign of Mold
Musty
odors in basements can be caused by water vapor entering through the concrete
walls and floor from moist soil around the basement.
A moist basement wall may be due to moisture in the air condensing when
it touches the cool wall surface.
The first step is to check to make sure your home
has proper drainage to avoid water vaporizing in the home. When building your
home, or making improvements, here is the best way to avoid moisture build-up in
basements. Install at least 6 inches of gravel underneath the basement concrete
floor. This forms a water drainage layer and radon removal layer. Place a vapor
retarder between the concrete floor and the granular layer to minimize radon and
moisture entry into the house. Place
4-inch drainage pipe along both the inside and outside of the concrete footing.
The top of the drainage pipe should
Next,
place filter fabric around the coarse gravel to prevent soil particles from
clogging the coarse gravel. Put gravel or a drainage mat next to the concrete
foundation wall (basement wall) to allow water to drain into the drainage pipe
and to keep wet soil away from the wall.
Then,
place a layer of low permeability soil, such as clay, near the surface to limit
the amount of water soaking into the ground next to the wall. Slope the ground
about 1 inch per foot away from the house. Extend down spouts several feet away
from the house. One inch of rain on a 1,000 square foot roof is equal to about
625 gallons of water, which isn’t something you want next to your basement.
Test
for Radon to Limit Cancer Risk
Cigarette
smoking is the leading cause of lung cancer in the United States. Radon exposure
is the second. Radon is a colorless, odorless, tasteless radioactive gas that
increases the potential for lung cancer. Radon has been found at elevated levels
in homes across the country.
Test
your home for radon. The testing device, normally a charcoal canister kit, is
set in the lowest habitable space (usually the basement during the heating
season when the house is kept closed) for a few days and then sent in for
analysis. If the reading exceeds the recommended level of four picocuries per
liter of air, further testing will be needed to determine if there is sufficient
radon in the living space to require action to reduce the level. Test kits are
available from some hardware stores, your local public health district or the
American Lung Association.
Basement
refinishing is frequently done by the homeowner. There are a few tips to think
about. Water vapor from moist soil under a concrete basement floor may come
through the floor and moisten the carpet. This creates an environment conducive
to mold growth, which may be a health hazard. A carpet pad is discouraged on the
floor if there is potential for moisture because the moisture is held by the
pad. Generally mold growth occurs on the backside of the pad and is not visible
unless the carpet is lifted.
Humidifiers
may Spew Bacteria and Fungi in the Air
Drag out the humidifier... Winter is here. They are great for adding
much-needed moisture to the air, but if they aren't cleaned properly, they can
bring pollutants into the home.
Microorganisms often grow in humidifiers equipped with tanks containing
standing water. The moist environment of a humidifier is also conducive for mold
growth. These microorganisms will be spread through the house by the humidifier.
Follow the manufacturer’s recommendation for cleaning and changing
water in the humidifier.
If you do not have the manufacturer’s recommendation, it is
recommended to thoroughly clean the unit every few days. Using a chlorine bleach
solution will help to kill any growth. Thoroughly rinse the unit after using the
bleach solution or other cleaner so these chemicals are not placed in the air.
Do not permit the area around the humidifier to stay wet since this may
lead to mold growth.
If you are getting frosty windows or ice build up, discontinue using
humidifier. Too much humidity can damage your house and promote the growth of
mold.
Attic
Ventilation is Often Overlooked
If you have spots on your ceiling, you know you have a moisture problem.
But for others, the problem is more subtle. Our attics are often overlooked when
trying to improve the quality of our homes. But it should not be ignored.
Adequate attic ventilation is required to prevent moisture problems in
the attic, including moist insulation and moisture that can soak through the
ceiling. Here is a guideline: For
natural ventilation, provide 1 square foot of vent area for each 300 square feet
of attic area if there is a vapor retarder (plastic) in the ceiling. If there
isn't a vapor retarder, make sure you have 1 square foot of vent area for each
150 square feet of attic area. Place half of the vent area near the roof peak
and half at the eaves. Provide air chutes or use other methods to assure that
eave vents are not blocked by insulation and that wind does not enter the
insulation, reducing its insulating value.
All
Air Filters Are Not Created Equal
Many families have one or
more people who suffer from allergies or asthma, often due to poor air quality.
But what many people do not realize is that they can do something about it.
The most effective and usually the least costly methods to limit indoor
pollutants are source control and ventilation. Air cleaners may reduce the
levels of certain pollutants, but air cleaning alone cannot adequately remove
all the pollutants in a typical indoor air environment.
Since particles float in the air, they are difficult to live with and
control. For example, pollutants can float around as a result of air movement
from a person walking from one room to the next, the furnace or air conditioner
blowing air, and the natural convection of warm air rising and cold air sinking.
These every-day occurrences cause particles
This natural settling may be so rapid that many air cleaners don’t
solve the problem of indoor pollutants.
To make sure your air cleaner is doing what it is supposed to be doing,
you need to look at two things. You will want to know the efficiency of the
device itself (the percentage of the pollutant removed as it goes through the
device) and the amount of air handled by the device. This is known as the
unit’s clean air delivery rate (CADR).
Filters are the most common particle removal method. The filters are
rated based on the size of particles removed. Other methods include
electrostatic and ion generators. Particles entering an electrostatic air
cleaner receive an intense positive electrical charge and adhere to plates,
which have to be removed and washed.
Ion generators charge the particles in a room so they are attracted to
each other or to surfaces in the house. Independent tests of ion generators have
shown no reduction in dust concentration in the air.
Ozone can be a by-product of electrostatic cleaners, particularly if the
units become loaded with material, and of ion generators. Ozone is a lung
irritant and should not be used in an occupied space.
Machines are available that purposely produce ozone as an indoor
cleansing agent. These should not be used in occupied areas. Ozone, which is an
oxidizing agent, is a potent lung irritant that can cause respiratory distress.
Although residential ozone-generating machines are promoted as air cleaners,
independent studies have shown that the machines do not effectively destroy
microbes or mold, remove odor sources or reduce indoor pollutants sufficiently
to provide any health benefits.
Keep your family safe by improving the quality of air in your house. For more information, see www.epa.gov/iaq/pubs/ozonegen.html.
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Last Modified on
Tuesday, January 24, 2006