| Office
of Radiation and Indoor Air (6607J)
August 1993, 402-F-93-005
Introduction
During a flood cleanup, the indoor air quality in your home or
office may appear to be the least of your problems. However, failure
to remove contaminated materials and to reduce moisture and humidity
can present serious long-term health risks. Standing water and
wet materials are a breeding ground for microorganisms, such as
viruses, bacteria, and mold. They can cause disease, trigger allergic
reactions, and continue to damage materials long after the flood.
This fact sheet discusses problems caused by microbial growth,
as well as other potential effects of flooding, on long-term indoor
air quality and the steps you can take to lessen these effects.
Although the information contained here emphasizes residential
flood cleanup, it is also applicable to other types of buildings.
Prepare for Cleanup
Read Repairing Your Flooded Home prepared
by the Federal Emergency Management Agency and the American Red
Cross. The booklet discusses flood safety issues and can save
your life. The booklet also contains detailed information on proper
methods for cleaning up your home. You should also consult
the wealth of information on the FEMA and American Red Cross web
sites on the subject.
This EPA fact sheet provides additional information not covered
in the original FEMA/American Red Cross booklet on indoor air
quality concerns related to flooding (however, because this fact
sheet was prepared in 1993, it is more than likely that FEMA and
the Red Cross do have more up-to-date information and resources
available which you should consult). Many of the methods used
for general cleanup, as detailed in the booklet, are the same
as those used to avoid problems with indoor air quality. For brevity,
we have not provided detail on the general methods used for cleanup
here. This fact sheet is intended to be used in conjunction with
the FEMA/American Red Cross booklet and resources.
Avoid Problems from Microbial Growth
Remove Standing Water
Standing water is a breeding ground for microorganisms, which
can become airborne and be inhaled. Where floodwater contains
sewage or decaying animal carcasses, infectious disease is of
concern. Even when flooding is due to rain water, the growth of
microorganisms can cause allergic reactions in sensitive individuals.
For these health reasons, and to lessen structural damage, all
standing water should be removed as quickly as possible.
Dry Out Your Home
Excess moisture in the home is an indoor air quality concern
for three reasons:
·
Microorganisms
brought into the home during flooding may present a health hazard.
These organisms can penetrate deep into soaked, porous materials
and later be released into air or water. Coming in contact with
air or water that contains these organisms can make you sick.
·
High
humidity and moist materials provide ideal environments for the
excessive growth of microorganisms that are always present in
the home. This may result in additional health concerns such as
allergic reactions.
·
Long
term increases in humidity in the home can also foster the growth
of dust mites. Dust mites are a major cause of allergic reactions
and asthma.
See Step 4 of the American Red Cross/FEMA booklet, Repairing
Your Flooded Home , on steps that should be taken to open
up and dry out ceilings, walls, and floors in the home.
Be patient. The drying out process could take several weeks,
and growth of microorganisms will continue as long as humidity
is high. If the house is not dried out properly, a musty odor,
signifying growth of microorganisms, can remain long after the
flood.
Remove Wet Materials
It can be difficult to throw away items in a home, particularly
those with sentimental value. However, keeping certain items that
were soaked by water may be unhealthy. Some materials tend to
absorb and keep water more than others. As a general rule: Materials
that are wet and cannot be thoroughly cleaned and dried should
be discarded, as they can remain a source of microbial growth.
Information on the types of water-damaged materials that should
be discarded are provided in Step 4 of the American Red Cross/FEMA
booklet, Repairing Your Flooded Home .
The booklet suggests that you may be able to dry out and save
certain building materials (for example, wallboard, fiberglass
insulation, and wall-to-wall carpeting that were soaked only with
clean rain water; and plaster). You may, however, want to consider
removing and replacing them to avoid indoor air quality problems.
Because they take a long time to dry, they may be a source of
microbial growth.
In addition, fiberboard, fibrous insulation, and disposable filters
should be replaced, if they are present in your heating and air
conditioning system and contacted water. (If a filter was designed
to be cleaned with water and was in contact with clean rain water
only, ensure that it is thoroughly cleaned before reinstalling.)
Avoid Problems from the Use of Cleaners and Disinfectants
The cleanup process involves thorough washing and disinfecting
of the walls, floors, closets, shelves, and contents of the house.
In most cases, common household cleaning products and disinfectants
are used for this task. FEMA also suggests the use of disinfectants
and sanitizers on the duct work for the heating and air conditioning
system, if it has been flooded.
Disinfectants and sanitizers contain toxic substances. The ability
of chemicals in other household products used for cleaning to
cause health effects varies greatly, from those with no known
health effect to those that are highly toxic. Read and follow
label instructions carefully, and provide fresh air by opening
windows and doors. If it is safe for you to use electricity and
the home is dry, use fans both during and after the use of disinfecting,
cleaning, and sanitizing products.
Be careful about mixing household cleaners and disinfectants
together. Check labels for cautions on this. Mixing certain types
of products can produce toxic fumes and result in injury and even
death.
Avoid Carbon Monoxide Poisoning
Carbon monoxide (CO) is a colorless, odorless gas that can be
lethal at high levels. Carbon monoxide levels can build up rapidly
if certain types of combustion devices (for example, gasoline-powered
generators, camp stoves and lanterns, or charcoal-burning devices)
are used indoors. Do not use combustion devices designed for outdoor
use indoors.
Avoid Problems from Airborne Asbestos and Lead Dust
Elevated concentrations of airborne asbestos can occur if asbestos-containing
materials present in the home are disturbed. Airborne asbestos
can cause lung cancer and mesothelioma, a cancer of the chest
and abdominal linings. If you know or suspect that your home contains
asbestos, contact the EPA TSCA Assistance Information Service
at (202) 554-1404 for information on steps you should take to
avoid exposure.
Lead is a highly toxic metal which produces a range of adverse
health effects, particularly in young children. Disturbance or
removal of materials containing lead-based paint may result in
elevated concentration of lead dust in the air. If you know or
suspect that your home contains lead-based paint, contact the
EPA lead hotline at 800 LEAD-FYI for information on steps you
should take to avoid exposure.
Additional Information
Copies of this fact sheet, and other information on indoor air
quality, are available from:
Indoor Air Quality Information Clearinghouse [IAQ INFO]
P.O. Box 37133
Washington, DC 20013-7133
Phone: 800 438-4318 or (703) 356-4020
(fax) (703) 356-5386 or e-mail at: iaqinfo@aol.com
The Federal Emergency Management Agency's Flood website, is at
(http://www.fema.gov/hazards/floods/ ).
Publications are available from:
FEMA
Publication Storage and Distribution
P.O. Box 2012
8241 Sandy Court, Suite A
Jessup, MD 20794-2012
Phone: 800-480-2520
Fax: 301-362-5335
The American Red Cross web site on flood cleanup is at - http://www.fema.gov/hazards/floods/
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