Tips
on Cleaning Up Your Home or Business
Even though these
articles refer to "home", the information applies to
any building that has been damaged by flooding, including businesses.
How to Dry
Out Your Home (or business)
This article outlines the most
complete process for drying out buildings which have been soaked
with flood water, including removal of debris and treatment of
walls, floors and woodwork.
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AS A PDF (120KB)
What Do I Do
About Mold in My Home (or business)
This article describes the health
effects of mold, how to find it and clean it up.
DOWNLOAD
AS A PDF (157KB)
Be patient. Drying out could take several weeks. Until your building is reasonably dry, damage caused by mildew and decay will continue. The musty odor will stay forever if your building is not dried out well.
FIRST FOLLOW THESE TIPS
AS YOU CLEAN UP!
Contacts: Ali Detar, 412-350-3171
Guillermo Cole, 412-578-8004
Ashley Henry, 412-350-5859
ALLEGHENY COUNTY OFFERS MOLD PREVENTION, CONTROL TIPS
PITTSBURGH, PA, Sept. 27, 2004
- The Allegheny County Health Department is offering the following
advice for dealing with mold issues arising
from recent flooding.
*Inhaling or touching mold or mold spores may cause allergic reactions in sensitive individuals, as well as irritation to the eyes, skin, nose, throat and lungs of non-allergic people.
* To prevent the growth of mold, dry out wet or damp areas as quickly as possible and keep humidity levels down. Open windows and doors to let in fresh air and sunlight. Use fans, de-humidifiers and air conditioners to help dry out flooded and damp environments.
* Scrub mold off hard surfaces with commercial cleaning products or detergent and water; then disinfect the surfaces with a solution of ¼ cup of bleach to one gallon of water.
* Make sure hard surfaces have completely dried after cleaning before painting or caulking them. Even after cleaning hard surfaces, mold may cause staining or cosmetic damage.
* Absorbent or porous materials, such as carpet, upholstery and ceiling tiles, that become moldy may have to be thrown away. Mold can grow on or fill in the empty spaces and crevices of porous materials, so the mold may be difficult or impossible to remove completely.
* To limit your exposure when cleaning moldy areas, wear a tight-fitting facemask, rubber gloves that extend to the middle of the forearm and goggles to protect your eyes.
* In most cases, if visible mold growth is present, testing or sampling is unnecessary.
* If you use a contractor for mold cleanup and remediation, be sure to ask for and check references. Look for contractors who are affiliated with professional organization.
TIPS ON CLEAN UP FROM THE
ALLEGHENY COUNTY HEALTH DEPARTMENT
Allegheny County Health Department
Bruce Dixon, MD, Director
How
To Dry Out Your Home (or business)
Floodwaters affect a
house in 3 ways:
1. The water damages materials. Wallboard will disintegrate if
it stays wet too long; wood can swell, warp, or rot; electrical
parts can short out, malfunction, and cause fires or shock.
2. Mud, silt, and unknown contaminants in the water not only get
everything dirty; they are also unhealthy.
3. Dampness promotes the growth of mildew, a mold or fungus that
can grow on everything.
The following steps work on
all three of these problems. It is very important to do these
steps in order.
Lower the Humidity
Everything will dry more quickly and clean more easily if
you can reduce the humidity in the house. There are many ways
to lower the humidity and stop the rot and mildew. But you’ll
have to delay using some methods if you have no electricity.
• Open up the house. If the humidity outside is lower than
it is indoors, and if the weather permits, open all the doors
and windows to exchange the moist indoor air for drier outdoor
air. Your body will tell you if the humidity is lower outdoors.
If the sun is out, it should be drier outside. If you have a thermometer
with a humidity gauge, you can monitor the indoor and outdoor
humidity. On the other hand, when temperatures drop at night,
an open house is warmer and will draw moisture indoors. At night,
and at other times when the humidity is higher outdoors, close
up the house.
• Open closet and cabinet doors. Remove drawers to let air
circulate. Drawers may stick because of swelling. Don’t try
to force them. Help them dry by opening up the back of the cabinet
so air can get into it. You will probably be able to remove the
drawers as the cabinet dries out.
• Use fans. Fans help move the air and dry out your home.
Do not use central air conditioning or the furnace blower if the
ducts were under water. They will blow out dirty air that might
contain contaminants from the sediment left in the ductwork. Clean
or hose out the ducts first.
• Run dehumidifiers. Dehumidifiers and window air conditioners
will reduce the moisture, especially in closed-up areas.
• Use desiccants. Desiccants (materials that absorb moisture)
are very useful in drying closets or other closed areas where
air cannot move through. Desiccants like those listed below are
usually available at hardware, grocery, or drug stores.
• Chemical dehumidifier packs used for drying boats and damp
closets.
• Cat litter made of clay.
• Calcium chloride pellets (used to melt ice in the winter).
Hang pellets in a pillowcase, nylon stocking, or other porous
bag. Put a bucket underneath to catch dripping water. Close the
closet or area being dried. Be careful. Calcium chloride can burn
your skin. It will also make the air salty, so do not use this
product near computers or other delicate equipment.
• Call a contractor. There are contractors who specialize
in drying out flooded buildings. They have large fans and dehumidifiers
that can dry out a house in a few days. Look in the yellow pages
under Fire and Water Damage Restoration or under Dehumidifying.
Be careful about contractors who inflate prices after a disaster
and about out-of-town contractors who request payment in advance.
Be patient. Drying your house could take several weeks. Until
your house is reasonably dry, damage caused by mildew and decay
will continue. The musty odor will stay forever if the house is
not dried out well.
Sort Contents and Discard
Debris
You have three types
of contents. They should go to three different places:
- Items you want to save
- Items to be thrown out
- Garbage
Things You Want to Save
Move things you want to save to a safe, dry place, such as the
second story or outside. The longer they sit in water, the more
damaged they become. Don’t leave wood furniture in the sun
because it will warp as it dries. To save an area rug, lay a sheet
or some other material on top of it before you roll it up so the
colors will not bleed. Clean it promptly.
Things You Don’t Want to Save
Put things you don’t want to save outside to dry until he
adjuster comes to confirm your losses. Take pictures or videotapes
and list each item for the record.
Garbage
Get rid of food and anything else that could spoil or go bad immediately.
Do not let garbage build up. Garbage piles will cause yet another
health hazard by attracting animals and insects. If your insurance
adjuster has not come, tell your agent or adjuster that you need
to get rid of potential health hazards. That person will tell
you how to make sure that your losses are covered. Then throw
the stuff out, preferably in sealed plastic garbage bags.
Do not take chances with frozen food if the electricity went off unless the food is still thoroughly frozen and contains ice crystals. As a rule, food will remain frozen for up to 3 days in a closed freezer without power. Do not refreeze thawed food. However, you can cook raw meat that was partially thawed and then freeze it.
Dispose of discarded items properly. Do not burn or bury them. There will usually be more frequent garbage pickups after a flood. Your local newspapers or local TV and radio stations will have announcements about trash pickup schedules and drop-off sites.
How Floodwaters Affect Your
Home
Once contents and debris have been cleared, the next step is to
get the water out of the ceilings and walls. How you drain and
dry your ceilings and walls depends on what they are made of.
Wallboard
Most ceilings and walls are covered with wallboard, especially
in newer homes. Wallboard acts like a sponge, drawing water up
above the flood level. It becomes very fragile if it stays wet
for long and will fall apart when bumped. When the wallboard finally
dries, there will still be mud and contaminants dried inside.
Wallboard that has been soaked by floodwater can be a permanent
health hazard. Therefore, this booklet recommends that you throw
out flooded wallboard. On the other hand, if the wallboard was
soaked by clean rainwater, it can be dried in place with plenty
of fresh air moving through the area.
Plaster
Plaster will survive a flood better than wallboard. You should
not need to replace it, but it will take a very long time to dry.
Sometimes the plaster will separate from its wood laths as it
dries. Then the wall will have to be removed and replaced.
Insulation
There are three main types of insulation, and each reacts differently
to floodwaters. Styrofoam survives best; it may only need to be
hosed off. Fiberglass batts should be thrown out if they are muddy.
If soaked by clean rainwater, remove them so the rest of the wall
can dry. They can be put back in the wall, but it will take a
very long time for them to dry. Cellulose (loose or blown-in treated
paper) insulation holds water for a long time. It can also lose
its anti-fungal and fire retardant abilities. Therefore, flooded
cellulose insulation should be replaced.
Wood
If it is allowed to dry naturally, wood will usually regain its
original shape. Different layers of laminated wood, such as plywood,
may dry at different rates, and that may cause the layers to separate.
Some contaminants will stay in the wood after it dries, but not
as much as stays in flooded wallboard. Wood studs and sills will
be covered by new wallboard and painted, so they are well removed
from human contact. Therefore, wet wood studs and sills do not
need to be replaced if they are allowed to dry properly.
Drain the Ceilings and Walls
Ceilings
Check for sagging ceilings. Drain them carefully. If the floodwaters
went above your ceiling, you should replace it if it is made of
wallboard. A plaster ceiling will dry eventually, but if it has
too many cracks or sags, you will have to tear it down and replace
it. Remove any wet insulation in the ceiling to allow the joists
to dry.
Walls
Remove water trapped within your walls. To check for water, take
off the baseboard. Stick an awl or knife into the wall about 2
inches above the floor (just above the 2 x 4 wood sill plate).
If water drips out, cut or drill a hole large enough to allow
water to drain freely. (Use a hand or cordless drill or saw to
avoid shock.) If you are going to replace the wallboard anyway,
you don’t have to be neat: use a hammer to knock out a hole.
If your walls are plaster, a knife won’t penetrate them.
Drill a hole above the sill plate to drain the water. (Use a hand
or cordless drill to avoid shock.) Do not use a hammer or chisel
on plaster because the plaster could shatter. In a newer home,
you may have metal sill plates. A metal sill acts as a gutter
at the bottom of the wall cavity. Drill a hole at floor level
to drain the water, using a hand or cordless drill.
Repeat the process to drain all the wall cavities. Depending on
the spacing between studs in your walls, make a hole every 16
inches or every 24 inches. Watch out for the wiring, which is
usually at the same height as your electrical outlets. If there
is wet insulation, you will have to remove the wallboard in order
to take out all the insulation.
Dry the Ceilings and Walls
Flood-soaked wallboard should be removed and thrown away. Plaster
and paneling can often be saved, but you still need to get air
circulating in the wall cavities to dry the studs and sills. Different
approaches are used for different materials.
Wallboard
If dirty floodwaters soaked the wallboard at least 4 feet above
the floor, take down all the wallboard and replace it. If the
water was less than 4 feet deep, remove the lower 4 feet of wallboard.
You can fill the gap with new 4 ft. x 8 ft. Wallboard sheets installed
sideways. If you have Styrofoam insulation ---or no insulation---and
the wallboard was soaked with clean rainwater, you can dry the
walls without removing the wallboard by using the technique explained
below for plaster walls. But you will need to remove wet insulation
if it is not Styrofoam.
Plaster Walls
If the plaster or wallboard is clean and in good shape, you can
drill or cut ventilating holes in each wall cavity. Place holes
low enough so they will be covered by the baseboard after the
wall dries out. Open up the wall on both sides of interior walls.
For exterior walls, drill or cut holes only on the inside of the
house. However, if there is wet insulation, you will have to remove
the plaster or wallboard in order to take out all the insulation.
Concrete Block
The cavities in a concrete block wall will drain on their own.
The water will not damage the concrete like it will wood or wallboard.
Wall Covering
Vinyl wall covering seals the wall and keeps it from drying out.
Wallpaper paste is also a favorite home for mold and mildew. For
these reasons, you should remove all wall covering that got wet
and throw it out. (If vinyl wall covering is loose on the bottom,
you may be able to save it by pulling it off the wall up to the
flood level. Clean and reapply it after everything dries).
Paneling
Carefully pry the bottom of each panel away from the wall Use
something to hold the bottom away from the sill so the cavities
can drain and dry out. You can nail them back into shape after
they and the studs dry out. However, if there is wet insulation,
you will have to remove the paneling in order to take out all
the insulation.
Dry the Floor
Air needs to move around flooded floors so they can dry out. This
usually means that you must remove the floor covering. Because
floodwaters contain mud and dirt, most soaked floor coverings
should be thrown away. Keep a piece of all discarded floor covering
so the adjuster can tell its value. Air needs to circulate below
the floor to dry it out. If the crawl space of your house in flooded,
pump it out. Remove any plastic sheets, vapor barriers, or insulation
from underneath the floor. (Be sure to replace them when the floor
and foundation are completely dry.)
If a house with a basement was flooded over the first floor, remove finished basement ceilings, or cut or drill holes between all the joists to allow circulation. Don’t cut or drill near electric lines or pipes. You have now reached the stage where your home should be protected from further damage. Outside holes have been patched, the utilities have been turned off, and the drying process has started. It may take days or weeks, depending on the humidity, for all the wood and walls to dry out. Patience now will prevent you having to do everything over again.
Mold in My Home: What Do I Do?
This packet is meant
to provide basic information to people who have experienced water
damage to their home and resulting mold concerns. It describes
health concerns related to mold
exposure, and it also provides general guidelines on prevention,
mold detection, as well as
cleanup of mold-contaminated materials.
MOLD
What are molds?
Molds are simple, microscopic organisms, present virtually everywhere,
indoors and outdoors. Molds,
along with mushrooms and yeasts, are fungi and are needed to break
down dead material and recycle
nutrients in the environment. For molds to grow and reproduce,
they need only a food source – any
organic material, such as leaves, wood, paper, or dirt— and
moisture. Because molds grow by digesting
the organic material, they gradually destroy whatever they grow
on. Sometimes, new molds grow on old
mold colonies. Mold growth on surfaces can often be seen in the
form of discoloration, frequently green,
gray, brown, or black but also white and other colors. Molds release
countless tiny, lightweight spores,
which travel through the air.
How am I exposed to indoor molds?
Everyone is exposed to some mold on a daily basis without evident
harm. It is common to find mold
spores in the air inside homes, and most of the airborne spores
found indoors come from outdoor
sources. Mold spores primarily cause health problems when they
are present in large numbers and
people inhale many of them. This occurs primarily when there is
active mold growth within home, office
or school where people live or work. People can also be exposed
to mold by touching contaminated
materials and by eating contaminated foods.
Can mold become a problem in my home?
Molds will grow and multiply whenever conditions are right—sufficient
moisture is available and organic
material is present. Be on the lookout in your home for common
sources of indoor moisture that may lead
to mold problems:
• Leaky roofs • Damp basements and crawl spaces
• Permeable foundations • Steam from cooking or showers
• Plumbing leaks • Dryers not exhausted to outside
• Overflows and backups from sinks and sewers • Humidifiers
Warping floors and discoloration of walls and ceilings can be
indications of moisture problems.
Condensation on windows or walls is also an important indication,
but it can sometimes be caused by an
indoor combustion problem! Have fuel-burning appliances routinely
inspected by your local utility
or a professional heating contractor.
Should I be concerned about mold in my home?
Yes. If indoor mold contamination is extensive, it can cause very
high and persistent airborne spore
exposures. Persons exposed to high spore levels can become sensitized
and develop allergies to the
mold or other health problems. Mold growth can damage your furnishings,
such as carpets, sofas and
cabinets. Clothes and shoes in damp closets can become soiled
and stained. In time, unchecked mold
growth can cause serious damage to the structural elements in
your home.
HEALTH EFFECTS
What symptoms are commonly seen with mold exposure?
Molds produce health effects through inflammation, allergy, or
infection. Allergic reactions (often referred
to as hay fever) are most common following mold exposure. Typical
symptoms that mold-exposed
persons report (alone or in combination) include:
• Respiratory problems, such as wheezing, difficulty breathing,
and shortness of breath.
• Nasal and sinus congestion
• Eye irritation (burning, watery, or reddened eyes
• Dry, hacking cough
• Skin rashes or irritation
• Nose and throat irritation
Headaches, memory problems, mood swings, nosebleeds, body aches
and pains, and fevers are
occasionally reported in mold cases, but their cause is not understood.
How much mold can make me sick?
It depends. For some people, a relatively small number of mold
spores can trigger an asthma attack or
lead to other health problems. For other persons, symptoms may
occur only when exposure levels are
much higher. Nonetheless, indoor mold growth is unsanitary and
undesirable. Basically, if you can see or
smell mold inside your home, take steps to identify and eliminate
the excess moisture and to cleanup
and remove the mold.
Are some molds more hazardous than others?
Allergic persons vary in their sensitivities to mold, both as
to the amount and the types to which they
react. In addition to their allergic properties, certain types
of molds, such as Stachybotris chartarum
(atra), may produce compounds that have toxic properties, which
are called mycotoxins. Mycotoxins are
not always produced, and whether a mold produces mycotoxins while
growing in a building depends on
what the mold is growing on, conditions such as temperature, pH,
humidity or other unknown factors.
When mycotoxins are present, they occur in both living and dead
mold spores and may be present in
materials that have become contaminated with molds. While Stachybotrys
is growing, a wet slime layer
covers its spores, preventing them from becoming airborne. However,
when the mold dies and dries up,
air currents or physical handling can cause spores to become airborne.
At present there is no environmental test to determine whether
Stachybotrys growth found in buildings is
producing toxins. There is also no blood or urine test that can
establish if an individual has been exposed
to Stachybotrys chartarum (atra) spores or its toxins.
Who is at greater risk when exposed to mold?
Exposure to mold is not healthy for anyone inside buildings. Therefore,
it is always best to identify and
correct high moisture conditions quickly before mold grows and
health problems develop. Some people
may have more severe symptoms or become ill more rapidly than
others:
• Individuals with existing respiratory conditions, such
as allergies, chemical sensitivities, or asthma.
• Persons with weakened immune systems (such as people with
HIV infection, cancer chemotherapy
patients, and so forth)
• Infants and young children
• The elderly
Anyone with health problems they believe due to molds should consult
a medical professional.
DETECTION OF MOLD
How can I tell if I have mold in my house?
You may suspect that you have mold if you see discolored patches
or cottony or speckled growth on
walls or furniture or if you smell an earthy or musty odor. You
also may suspect mold contamination if
mold-allergic individuals experience some of the symptoms listed
above when in the house. Evidence of
past or ongoing water damage should also trigger more thorough
inspection. You may find mold growth
underneath water-damaged surfaces or behind walls, floors or ceilings.
Should I test my home for mold?
Testing is not recommended as a first step to determine if you
have a mold problem. Reliable air
sampling for mold can be expensive and requires expertise and
equipment that is not available to the
general public. Owners of individual private homes and apartment
generally will need to pay a contractor
to carry out such sampling, because insurance companies and public
health agencies seldom provide
this service. Mold inspection and cleanup is usually considered
a housekeeping task that is the
responsibility of homeowner or landlord, as are roof and plumbing
repairs, house cleaning, and yard
maintenance.
Another reason the health department does not recommend testing
for mold contamination is that there
are few available standards for judging what is an acceptable
quantity of mold. In all locations, there is
some level of airborne mold outdoors. If sampling is carried out
in a home, an outdoor air sample also
must be collected at the same time as the indoor samples, to provide
a baseline measurement. Because
individual susceptibility varies so greatly, sampling is at best
a general guide.
The simplest way to deal with a suspicion of mold contamination
is: If you can see or smell mold, you
likely have a problem and should take the steps outlined below.
Mold growth is likely to recur unless the
source of moisture that is allowing mold to grow is removed and
the contaminated area is cleaned.
GENERAL CLEAN-UP PROCEDURES
The following is intended as an overview for homeowners or apartment
dwellers. We recommend that
you consult one of several more thorough documents currently available
as guidance, listed in the
USEFUL PUBLICATIONS section at the end of this article.
Elements of the Clean-up Procedures
• Identify and eliminate sources of moisture.
• Identify and assess the magnitude and area of mold contamination
• Clean and dry moldy areas – use containment of affected
areas
• Bag and dispose of all material that may have moldy residues,
such as rags, paper, leaves.
Assessing the Size of the Mold Problem
There will be a significant difference in the approach used for
a small mold problem – total area affected
is less than 10 ft2 – and a large contamination problem –
more than 100 ft2. In the case of a relatively
small area, the cleanup can be handled by the homeowner or maintenance
staff, using personal
protective equipment (see below). However, for cases of much larger
areas, it is advisable that an
experienced, professional contractor be used. For in-between sized
cases, the type of containment and
personal protection equipment to be used will be a matter of judgment.
Can cleaning up mold be hazardous to my health?
Yes. During the cleaning process, you may be exposed to mold,
strong detergents, and disinfectants.
Spore counts may be 10 to 1000 times higher than background levels
when mold-contaminated
materials are disturbed. Take steps to protect you and your family’s
health during cleanup:
• When handling or cleaning moldy materials, it is important
to use a respirator to protect yourself from
inhaling airborne spores.
Respirators can be purchased from hardware stores; select one
that is effective for particle removal
(sometimes referred to as an N-95 particulate respirator). However,
respirators that remove particles will
not protect you from fumes (such as bleach). Minimize exposure
when using bleach or other
disinfectants by ensuring good ventilation of the area.
• Wear protective clothing that is easily cleaned or discarded.
• Use rubber gloves.
• Try cleaning a test area first. If you feel that this activity
adversely affected your health, you should
consider paying a licensed contractor or other experienced professional
to carry out the work.
• Ask family members or bystanders to leave areas that are
being cleaned.
• Work for short time periods and rest in a location with
fresh air.
• Air out your house well during and after the work.
Never use a gasoline engine indoors (e.g., water pump, pressure
washer or generator), as you could
expose your family to toxic carbon monoxide.
Removal of Moldy Materials
Clean up should begin after the moisture source is fixed and excess
water has been removed. Wear
gloves when handling moldy materials.
• Discard porous materials (for example, ceiling tiles, sheetrock,
carpeting, and wood products).
• Bag and discard moldy items; if properly enclosed, items
can be disposed with household trash.
• Dry affected areas for 2 or 3 days.
Spores are more easily released when moldy materials dry out,
hence it is advisable to remove moldy
items as soon as possible.
If there was flooding, sheetrock should be removed to a level
above the high-water mark. Visually
inspect the wall interior and remove any mold-contaminated materials.
What can I save? What should I toss?
You should discard moldy items that are porous and from which
it will be difficult to remove mold
completely: paper, rags, wallboard, rotten wood, carpet, drapes,
and upholstered furniture.
Contaminated carpet is often difficult to thoroughly clean, especially
when the backing and/or padding
can become moldy. Solid materials – glass, plastic, and metal
– can generally be kept after they are
thoroughly cleaned.
Clean-up
When attempting to clean less porous items (i.e., solid items
such as floors, cabinets, solid furniture), the
first step is to remove as much mold as possible. A cleaning detergent
is effective for this purpose.
Wear gloves, mask and eye protection when doing this cleanup.
• Use non-ammonia soap or detergent, or a commercial cleaner,
in hot water, and scrub the entire area
that is affected by the mold.
• Use a stiff brush or cleaning pad on cement-block walls
or other uneven surfaces.
• Rinse cleaned items with water and dry thoroughly. A wet/dry
vacuum cleaner is helpful for removing
water and cleaning items.
Disinfection of Contaminated Materials
Disinfecting agents can be toxic for humans, not just molds. They
should be used only when necessary
and should be handled with caution.
Disinfectants are intended to be applied to thoroughly cleaned
materials and are used to ensure that
most microorganisms have been killed. Therefore, do not use disinfectants
instead of, or before,
cleaning materials with soap or detergent. Removal of mold growth
from nonporous materials usually is
sufficient. Wear gloves, mask and eye protection when using disinfectants.
• After thoroughly cleaning and rinsing contaminated materials,
a solution of 10% household bleach (for
example, 1½ cup household bleach per gallon of water) can
be used as a disinfectant.
• Using bleach straight from the bottle is actually LESS
effective than diluted bleach.
• Keep the disinfectant on the treated material for the prescribed
time before rinsing or drying; typically
10 minutes is recommended for a bleach solution
• Bleach fumes can irritate the eyes, nose, and throat, and
damage clothing and shoes. Make sure
working areas are well ventilated.
• When disinfecting a large structure, make sure that the
entire surface is wetted (for example, the floors,
joists, and posts).
• Properly collect and dispose extra disinfectant and runoff.
• Never mix bleach with ammonia; toxic fumes may be produced.
Can air ducts become contaminated with mold?
Yes. Air duct systems can become contaminated with mold. Duct
systems may be constructed of bare
sheet metal, sheet metal with fibrous glass insulation on the
exterior, or sheet metal with an internal
fibrous glass liner, or they may be made entirely of fibrous glass.
Bare sheet metal systems and sheet
metal with exterior fibrous glass insulation can be cleaned and
disinfected. If water damaged, ductwork
made of sheet metal with an internal fibrous glass liner or made
entirely of fibrous glass will often need to
be removed and discarded. Ductwork in difficult-to-reach locations
may have to be abandoned. If you
have other questions, contact an air duct cleaning professional
or licensed contractor.
Can ozone air cleaners help remove indoor mold or reduce odors?
Sometimes air cleaners are promoted to remove indoor mold or associated
odors, and some of these are
designed to produce ozone. Ozone is a strong oxidizing agent that
is used as a disinfectant in water and
sometimes to eliminate odors. However, ozone is a known lung irritant.
Ozone generators have been
shown to sometimes produce indoor levels above the safe limit.
Furthermore, it has been shown that
ozone is not effective in controlling molds and other microbial
contamination, even at concentrations far
above safe health levels. Also, ozone may damage materials in
the home, for example, cause rubber
items to become brittle. For these reasons, it is strongly recommended
that you NOT use an ozone air
cleaner in any occupied space.
How can I prevent indoor mold problems in my home?
Inspect your home regularly for the indications and sources of
indoor moisture and mold listed on Page
1. Take steps to eliminate sources of water as quickly as possible.
If a leak or flooding occurs, it is
essential to act quickly:
• Stop the source of leak or flooding.
• Remove excess water with mops or wet vacuum.
• Whenever possible, move wet items to a dry and well ventilated
area or outside to expedite drying.
Move rugs and pull up areas of wet carpet as soon as possible.
• Open closet and cabinet doors and move furniture away from
walls to increase circulation.
• Run portable fans to increase air circulation. Do NOT use
the home’s central blower if flooding has
occurred in it or in any of the ducts. Do NOT use fans if mold
may have already started to grow -- more
than 48 h since flooding.
• Run dehumidifiers and window air conditioners to lower
humidity.
• Do NOT turn up the heat or use heaters in confined areas,
as higher temperatures increase the rate of
mold growth.
• If water has soaked inside the walls, it may be necessary
to open wall cavities, remove baseboards,
and/or pry open wall paneling.
USEFUL PUBLICATIONS
Biological Pollutants in Your Home. Concise booklet by U.S. EPA
aimed at affected homeowner.
Mold and Moisture. Appendix H in the U.S. EPA IAQ Tools for Schools
Clean-up Guidance
Repairing Your Flooded Home. Excellent resource by the American
Red Cross and FEMA, with
details on technical & logistical issues.
A Brief Guide to Mold, Moisture, and Your Home. New guidance by
the U.S. EPA for homes and
non-commercial residences.
Mold Remediation in Schools and Commercial Buildings. Guidance
by U.S. EPA for
commercial properties.
Additional Information:
U.S. EPA IAQ INFO, 800-438-4318
www.epa.gov/iaq
Allegheny County Health Department
Housing and Community Environment Program
3190 Sassafras Way
Pittsburgh, PA 15201-1443
412-350-4046 (or 412-687-ACHD 24-hours a day)
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