Fungi Hazards and Flood Cleanup
Flood conditions contribute to the growth and transmission of many kinds of
fungi, some of which can cause sickness. Cleanup workers are at increased risk
of exposure to airborne fungi and their spores because they often handle moldy
building materials, decaying vegetable matter, rotting waste material, and other
fungus-contaminated debris. The fungal material is carried into the respiratory
tract when airborne particles are inhaled.
There are many different kinds of fungi,
including mildew, molds, rusts, and yeasts.
Most of these are harmless, but some can
cause respiratory and other disorders when
workers inhale or come into contact with
fungi. Inhalation is the route of exposure of
most concern to flood cleanup workers. The
recommendations below offer strategies for
workers renovating flooded buildings, homes,
and structures to protect themselves while
handling building materials that are visibly
contaminated with fungi.
For workers cleaning up flooded buildings,
homes, and other structures, excessive moisture
or water accumulation indoors will
encourage the growth of the fungi that are
already present. Some fungi have the potential
to cause adverse health effects such as
allergic responses and asthma attacks.
Individuals who are sensitive to molds may
have signs and symptoms of allergic reactions
such as nasal stuffiness, eye irritation,
and wheezing. These individuals should minimize
fungal exposure by wearing respirators,
gloves, and eye protection. They should also
seek to eliminate fungi, as described below.
In addition, repeated or prolonged contact of
the skin with flood water and continuous
sweating can lead to fungal skin infections.
These can be minimized or avoided by washing
the skin with warm, soapy water and
keeping it as dry as possible.
What to Do If Symptoms Develop
If a cleanup worker experiences severe allergic or skin symptoms, or severe flu-like
symptoms, he or she should seek medical
advice. A health care provider can determine
whether medication or any other precautions
Tips to Remember
For all workers who may be exposed to
mold and fungi:
- Avoid breathing dust (fungal spores) generated
by moldy building materials, crops,
and other materials.
- Consider using an N-95 NIOSH-approved
disposable respirator as a minimum when
working with moldy or damp hay, grain,
compost, or building materials. Respirator
protection must be used in accordance
with OSHA’s Respiratory Protection standard
(29 CFR 1910.134, Appendix D).
- Consider discarding all water damaged
materials. Articles that are visibly contaminated
with mold should be discarded.
When in doubt, throw it out.
- Surfaces that have a light covering of mold
should be scrubbed with warm, soapy
water and rinsed with a disinfectant made
of 1/2 cup liquid household bleach mixed
into one gallon of water.
- CAUTION: Do not mix bleach with other
cleaning products that contain ammonia.
- After working with mold-contaminated
materials, wash thoroughly, including the
hair, scalp, and nails.
- If the safety of food or beverage is questionable,
throw it out. Only drink safe drinking
water that has been bottled, boiled, or
treated until there is confirmation that the community water supply is safe for consumption.
When cleaning up or renovating buildings
and homes that have been flooded, consider
the following recommendations:
- NIOSH-approved respirators are strongly
recommended. Respiratory protection such
as the N-95 must be used in accordance
with OSHA’s Respiratory Protection standard
(29 CFR 1910.134). Also wear gloves
and eye protection.
- Remove building materials and furnishings
that are wet and may become contaminated
with mold growth and place them in
sealed impermeable bags or closed containers.
Large items with heavy mold
growth should be covered with polyethylene
sheeting and sealed with duct tape
before being removed from the area. These
materials can usually be discarded as ordinary
- Remove and discard porous organic materials
that have become wet or are visibly
contaminated (e.g., damp insulation in ventilation
system, moldy ceiling tiles, and
mildewed carpets). Again, these materials
can usually be discarded as ordinary construction
- Clean and disinfect nonporous surfaces
where microbial growth has occurred with
detergents, chlorine-generating slimicides,
or other biocides and ensure that these
cleaners have been removed before air
handling units are turned on. When using a
biocide or disinfectant, consult the material
safety data sheet (MSDS) or warning label for the appropriate personal protective
equipment (PPE) that should be used when
handling these chemicals. Chemical safety
and handling must be done in accordance
with OSHA’s Hazard Communication standard
(29 CFR 1910.1200). PPE, such as
NIOSH-approved respirators with the
appropriate chemical cartridges, can be
used. Wear gloves and eye protection also.
For cleanup workers in rural and agricultural
- Silos and other enclosed areas should be
vented prior to entry. However, this may
not eliminate the problem entirely. If a
worker is transporting or working with
moldy animal feed, exposures are likely to
be increased if the feed and the worker are
enclosed in a barn, silo or other structure.
Workers will still need to wear respirators.
NOTE: Any entry in a silo or other confined
space must be done in accordance with
OSHA’s Permit-Required Confined Spaces
standard (29 CFR 1910.146).
- Workers uncapping a silo, shoveling grain,
or working with feed, especially in any
enclosed space, should always wear at a
minimum a NIOSH-approved N-95 particulate
respirator. Grain and hay should be
stored when fully dry.
For additional information concerning fungi,
health effects, and addressing flood damaged
materials, please visit OSHA's Safety
and Health Topics web page on Molds and
Fungi at: www.osha.gov/SLTC/molds/
This is one in a series of informational fact sheets highlighting OSHA programs, policies or standards. It does not impose any new compliance requirements. For a comprehensive list of compliance requirements of OSHA standards or regulations, refer to Title 29 of the Code of Federal Regulations. This information will be made available to sensory impaired individuals upon request. The voice phone is (202) 693-1999; teletypewriter (TTY) number: (877) 889-5627.
For more complete information:
Safety and Health
U.S. Department of Labor