Mold,
Moisture, and
Your Home
Mold,
Moisture,
and Your
Home
Mold Basics
-
The key
to mold
control
is
moisture
control.
-
If mold
is a
problem
in your
home,
you
should
clean up
the mold
promptly
and
fix the
water
problem.
-
It is
important
to dry
water-damaged
areas
and
items
within
24-48
hours to
prevent
mold
growth.
Why is
mold growing in
my home?
Molds are
part of the
natural
environment.
Outdoors,
molds play a
part in
nature by
breaking
down dead
organic
matter such
as fallen
leaves and
dead trees,
but indoors,
mold growth
should be
avoided.
Molds
reproduce by
means of
tiny spores;
the spores
are
invisible to
the naked
eye and
float
through
outdoor and
indoor air.
Mold may
begin
growing
indoors when
mold spores
land on
surfaces
that are
wet. There
are many
types of
mold, and
none of them
will grow
without
water or
moisture.
Can
mold cause
health
problems?
Molds are
usually not a
problem indoors,
unless mold
spores land on a
wet or damp spot
and begin
growing. Molds
have the
potential to
cause health
problems. Molds
produce
allergens
(substances that
can cause
allergic
reactions),
irritants, and
in some cases,
potentially
toxic substances
(mycotoxins).
Inhaling or
touching mold or
mold spores may
cause allergic
reactions in
sensitive
individuals.
Allergic
responses
include hay
fever-type
symptoms, such
as sneezing,
runny nose, red
eyes, and skin
rash
(dermatitis).
Allergic
reactions to
mold are
common. They
can be immediate
or delayed.
Molds can also
cause asthma
attacks in
people with
asthma who are
allergic to
mold. In
addition, mold
exposure can
irritate the
eyes, skin,
nose, throat,
and lungs of
both
mold-allergic
and non-allergic
people.
Symptoms other
than the
allergic and
irritant types
are not commonly
reported as a
result of
inhaling mold.
Research on mold
and health
effects is
ongoing. This
brochure
provides a brief
overview; it
does not
describe all
potential health
effects related
to mold
exposure. For
more detailed
information
consult a health
professional.
You may also
wish to consult
your state or
local health
department.
How do I
get rid of mold?
It is
impossible
to get rid
of all mold
and mold
spores
indoors,
some mold
spores will
be found
floating
through the
air and in
house dust.
The mold
spores will
not grow if
moisture is
not
present.
Indoor mold
growth can
and should
be prevented
or
controlled
by
controlling
moisture
indoors. If
there is
mold growth
in your
home, you
must clean
up the mold
and fix the
water
problem. If
you clean up
the mold,
but don't
fix the
water
problem,
then, most
likely, the
mold problem
will come
back.
Who Should
Do the
Cleanup
Who should
do the
cleanup
depends on a
number of
factors.
One
consideration
is the size
of the mold
problem. If
the moldy
area is less
than about
10 square
feet (less
than roughly
a 3 ft. by 3
ft. patch),
in most
cases, you
can handle
the job
yourself,
following
the
guidelines
below.
-
If
there
has
been
a
lot
of
water
damage,
and/or
mold
growth
covers
more
than
10
square
feet,
consult
the
U.S.
Environmental
Protection
Agency
(EPA)
guide:
Mold
Remediation
in
Schools
and
Commercial
Buildings.
-
If
you
choose
to
hire
a
contractor
(or
other
professional
service
provider)
to
do
the
cleanup,
make
sure
the
contractor
has
experience
cleaning
up
mold.
Check
references
and
ask
the
contractor
to
follow
the
recommendations
of
the
EPA,
the
guidelines
of
the
American
Conference
of
Governmental
Industrial
Hygenists
(ACGIH),
or
other
guidelines
from
professional
or
government
organizations.
-
If
you
suspect
that
the
heating/ventilation/air
conditioning
(HVAC)
system
may
be
contaminated
with
mold
(it
is
part
of
an
identified
moisture
problem,
for
instance,
or
there
is
mold
near
the
intake
to
the
system),
consult
EPA's
guide
Should
You
Have
the
Air
Ducts
in
Your
Home
Cleaned?
before
taking
further
action.
Do
not
run
the
HVAC
system
if
you
know
or
suspect
that
it
is
contaminated
with
mold
- it
could
spread
mold
throughout
the
building.
-
If
the
water
and/or
mold
damage
was
caused
by
sewage
or
other
contaminated
water,
then
call
in a
professional
who
has
experience
cleaning
and
fixing
buildings
damaged
by
contaminated
water.
-
If
you
have
health
concerns,
consult
a
health
professional
before
starting
cleanup.
Tips and
techniques
The tips and
techniques
presented in
this section
will help
you clean up
your mold
problem.
Professional
cleaners or
remediators
may use
methods not
covered in
this
publication.
Please note
that mold
may cause
staining and
cosmetic
damage. It
may not be
possible to
clean an
item so that
its original
appearance
is
restored.
-
Fix
plumbing
leaks
and
other
water
problems
as
soon
as
possible.
Dry
all
items
completely.
-
Scrub
mold
off
hard
surfaces
with
detergent
and
water,
and
dry
completely.
-
Absorbent
or
porous
materials,
such
as
ceiling
tiles
and
carpet,
may
have
to
be
thrown
away
if
they
become
moldy.
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.
-
Avoid
exposing
yourself
or
others
to
mold.
-
Do
not
paint
or
caulk
moldy
surfaces.
-
Clean
up
the
mold
and
dry
the
surfaces
before
painting.
Paint
applied
over
moldy
surfaces
is
likely
to
peel.
If
you
are
unsure
about
how
to
clean
an
item,
or
if
the
item
is
expensive
or
of
sentimental
value,
you
may
wish
to
consult
a
specialist.
Specialists
in
furniture
repair,
restoration,
painting,
art
restoration
and
conservation,
carpet
and
rug
cleaning,
water
damage,
and
fire
or
water
restoration
are
commonly
listed
in
phone
books.
Be
sure
to
ask
for
and
check
references.
Look
for
specialists
who
are
affiliated
with
professional
organizations.
What
to
Wear
When
Cleaning
Moldy
Areas
-
Avoid
breathing
in mold
or mold
spores.
In order
to limit
your
exposure
to
airborne
mold,
you may
want to
wear an
N-95
respirator,
available
at many
hardware
stores
and from
companies
that
advertise
on the
Internet.
(They
cost
about
$12 to
$25.)
Some
N-95
respirators
resemble
a paper
dust
mask
with a
nozzle
on the
front,
others
are made
primarily
of
plastic
or
rubber
and have
removable
cartridges
that
trap
most of
the mold
spores
from
entering.
In order
to be
effective,
the
respirator
or mask
must fit
properly,
so
carefully
follow
the
instructions
supplied
with the
respirator.
Please
note
that the
Occupational
Safety
and
Health
Administration
(OSHA)
requires
that
respirators
fit
properly
(fit
testing)
when
used in
an
occupational
setting;
consult
OSHA for
more
information
(800-321-OSHA).
-
Wear
gloves.
Long
gloves
that
extend
to the
middle
of the
forearm
are
recommended.
When
working
with
water
and a
mild
detergent,
ordinary
household
rubber
gloves
may be
used.
If you
are
using a
disinfectant,
a
biocide
such as
chlorine
bleach,
or a
strong
cleaning
solution,
you
should
select
gloves
made
from
natural
rubber,
neoprene,
nitrile,
polyurethane,
or PVC.
Avoid
touching
mold or
moldy
items
with
your
bare
hands.
-
Wear
goggles.
Goggles
that do
not have
ventilation
holes
are
recommended.
Avoid
getting
mold or
mold
spores
in your
eyes.
How Do I
Know When
the
Remediation
or Cleanup
is Finished?
You must have
completely fixed
the water or
moisture problem
before the
cleanup or
remediation can
be considered
finished.
-
You should
have
completed
mold
removal.
Visible mold
and moldy
odors should
not be
present.
Please note
that mold
may cause
staining and
cosmetic
damage.
-
You should
have
revisited
the site(s)
shortly
after
cleanup and
it should
show no
signs of
water damage
or mold
growth.
-
People
should have
been able to
occupy or
re-occupy
the area
without
health
complaints
or physical
symptoms.
-
Ultimately,
this is a
judgment
call; there
is no easy
answer. If
you have
concerns or
questions
call the EPA
Indoor Air
Quality
Information
Clearinghouse
IAQ INFO at
(800)
438-4318.
Moisture and
Mold
Prevention
and Control
Tips
-
Moisture
control is
the key to
mold
control, so
when water
leaks or
spills occur
indoors -
ACT
QUICKLY. If
wet or damp
materials or
areas are
dried 24-48
hours after
a leak or
spill
happens, in
most cases
mold will
not grow.
-
Clean and
repair roof
gutters
regularly.
-
Make sure
the ground
slopes away
from the
building
foundation,
so that
water does
not enter or
collect
around the
foundation.
-
Keep air
conditioning
drip pans
clean and
the drain
lines
unobstructed
and flowing
properly.
-
Keep indoor
humidity
low. If
possible,
keep indoor
humidity
below 60
percent
(ideally
between 30
and 50
percent)
relative
humidity.
Relative
humidity can
be measured
with a
moisture or
humidity
meter, a
small,
inexpensive
($10-$50)
instrument
available at
many
hardware
stores.
-
If you see
condensation
or moisture
collecting
on windows,
walls or
pipes ACT
QUICKLY to
dry the wet
surface and
reduce the
moisture/water
source.
Condensation
can be a
sign of high
humidity.
Actions
that will help
to reduce
humidity:
-
Vent
appliances
that produce
moisture,
such as
clothes
dryers,
stoves, and
kerosene
heaters to
the outside
where
possible.
(Combustion
appliances
such as
stoves and
kerosene
heaters
produce
water vapor
and will
increase the
humidity
unless
vented to
the
outside.)
-
Use air
conditioners
and/or
de-humidifiers
when needed.
-
Run the
bathroom fan
or open the
window when
showering.
Use exhaust
fans or open
windows
whenever
cooking,
running the
dishwasher
or
dishwashing,
etc.
Actions
that will help
prevent
condensation:
-
Reduce the
humidity
(see above).
-
Increase
ventilation
or air
movement by
opening
doors and/or
windows,
when
practical.
Use fans as
needed.
-
Cover cold
surfaces,
such as cold
water pipes,
with
insulation.
-
Increase air
temperature.
Testing
or
Sampling
for Mold
Is sampling
for mold
needed? In
most cases,
if visible
mold growth
is present,
sampling is
unnecessary.
Since no EPA
or other
federal
limits have
been set for
mold or mold
spores,
sampling
cannot be
used to
check a
building's
compliance
with federal
mold
standards.
Surface
sampling may
be useful to
determine if
an area has
been
adequately
cleaned or
remediated.
Sampling for
mold should
be conducted
by
professionals
who have
specific
experience
in
designing
mold
sampling
protocols,
sampling
methods, and
interpreting
results.
Sample
analysis
should
follow
analytical
methods
recommended
by the
American
Industrial
Hygiene
Association
(AIHA), the
American
Conference
of
Governmental
Industrial
Hygienists
(ACGIH), or
other
professional
organizations.
Suspicion of
hidden mold
You may
suspect
hidden mold
if a
building
smells
moldy, but
you cannot
see the
source, or
if you know
there has
been water
damage and
residents
are
reporting
health
problems.
Mold may be
hidden in
places such
as the back
side of dry
wall,
wallpaper,
or paneling,
the top side
of ceiling
tiles, the
underside of
carpets and
pads, etc.
Other
possible
locations of
hidden mold
include
areas inside
walls around
pipes (with
leaking or
condensing
pipes), the
surface of
walls behind
furniture
(where
condensation
forms),
inside
ductwork,
and in roof
materials
above
ceiling
tiles (due
to roof
leaks or
insufficient
insulation).
Investigating
hidden mold
problems
Investigating
hidden mold
problems may
be difficult
and will
require
caution when
the
investigation
involves
disturbing
potential
sites of
mold growth.
For example,
removal of
wallpaper
can lead to
a massive
release of
spores if
there is
mold growing
on the
underside of
the paper.
If you
believe that
you may have
a hidden
mold
problem,
consider
hiring an
experienced
professional.
Cleanup and
Biocides
Biocides are
substances
that can
destroy
living
organisms.
The use of a
chemical or
biocide that
kills
organisms
such as mold
(chlorine
bleach, for
example) is
not
recommended
as a routine
practice
during mold
cleanup.
There may be
instances,
however,
when
professional
judgment may
indicate its
use (for
example,
when
immune-compromised
individuals
are
present). In
most cases,
it is not
possible or
desirable to
sterilize an
area; a
background
level of
mold spores
will remain
- these
spores will
not grow if
the moisture
problem has
been
resolved. If
you choose
to use
disinfectants
or biocides,
always
ventilate
the area and
exhaust the
air to the
outdoors.
Never mix
chlorine
bleach
solution
with other
cleaning
solutions or
detergents
that contain
ammonia
because
toxic fumes
could be
produced.
Please note:
Dead mold
may still
cause
allergic
reactions in
some people,
so it is not
enough to
simply kill
the mold, it
must also be
removed.
Ten
Things
You
Should
Know
About
Mold
1.
Potential
health
effects
and
symptoms
associated
with
mold
exposures
include
allergic
reactions,
asthma,
and
other
respiratory
complaints.
2.
There is
no
practical
way to
eliminate
all mold
and mold
spores
in the
indoor
environment;
the way
to
control
indoor
mold
growth
is to
control
moisture.
3. If
mold is
a
problem
in your
home or
school,
you must
clean up
the mold
and
eliminate
sources
of
moisture.
4. Fix
the
source
of the
water
problem
or leak
to
prevent
mold
growth.
5.
Reduce
indoor
humidity
(to
30-60%)
to
decrease
mold
growth
by:
a. venting bathrooms, dryers, and other moisture-generating sources to the outside;
b. using air conditioners and de-humidifiers;
c. increasing ventilation;
d. and using exhaust fans whenever cooking, dishwashing, and cleaning
6.
Clean
and dry
any damp
or wet
building
materials
and
furnishings
within
24-48
hours to
prevent
mold
growth.
7.
Clean
mold off
hard
surfaces
with
water
and
detergent,
and dry
completely.
Absorbent
materials
such as
ceiling
tiles,
that are
moldy,
may need
to be
replaced.
8.
Prevent
condensation:
Reduce
the
potential
for
condensation
on cold
surfaces
(i.e.,
windows,
piping,
exterior
walls,
roof, or
floors)
by
adding
insulation.
9.
In areas
where
there is
a
perpetual
moisture
problem,
do not
install
carpeting
(i.e.,
by
drinking
fountains,
by
classroom
sinks,
or on
concrete
floors
with
leaks or
frequent
condensation).
10.
Molds
can be
found
almost
anywhere;
they can
grow on
virtually
any
substance,
providing
moisture
is
present.
There
are
molds
that can
grow on
wood,
paper,
carpet,
and
foods.
