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Workplace Mold
U. S. Department of
Labor’s “A Brief Guide to Mold in the Workplace” is a complete
guideline for “building managers, custodians, and
others who are responsible for building maintenance” on how to deal
with mold and moisture problem in the building or workplace. It also
provides: recommendations on how to prevent mold growth, tips on how to
“protect the health of building occupants and workers
involved in mold cleanup and prevention”, guidelines for mold remediation,
and information about the health effects of mold exposure.
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Occupational Safety and Health Administration
Directorate of Science, Technology and Medicine
Office of Science and Technology Assessment
A Brief Guide
to Mold in the Workplace
Safety
and Health Information Bulletins
SHIB 03-10-10
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This Safety and Health Information Bulletin is not a standard or
regulation, and it creates no new legal obligations. The Bulletin is
advisory in nature, informational in content, and is intended to assist
building managers, custodians, and others who are responsible for
building maintenance. Contractors and other professionals (e.g.,
environmental consultants and health or safety professionals) who
respond to mold and moisture situations in buildings, as well as members
of the general public, also may want to refer to these guidelines.
The Occupational Safety and Health Act requires employers to comply with
hazard-specific safety and health standards as issued and enforced by
either the Federal Occupational Safety and Health Administration (OSHA),
or an OSHA-approved State Plan. In addition, Section 5(a)(1), the
General Duty Clause, requires employers to provide their employees with
a workplace free from recognized hazards likely to cause death or
serious physical harm. Employers can be cited for violating the General
Duty Clause if there is such a recognized hazard and they do not take
reasonable steps to prevent or abate the hazard. However, failure to
implement these guidelines is not, in itself, a violation of the General
Duty Clause. Citations can only be based on standards, regulations, and
the
General Duty Clause.
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Introduction
Concern about indoor exposure to mold has increased
along with public awareness that exposure to mold can cause a variety of
health effects and symptoms, including allergic reactions. This safety and
health information bulletin provides recommendations for the prevention of
mold growth and describes measures designed to protect the health of
building occupants and workers involved in mold cleanup and prevention. This
bulletin is directed primarily at building managers, custodians, and others
responsible for building maintenance, but may also be used as a basic
reference for those involved in mold remediation. By reading this safety and
health information bulletin, individuals with little or no experience with
mold remediation may be able to reasonably judge whether mold contamination
can be managed in-house or whether outside assistance is required. The
advice of a medical professional should always be sought if there are any
emerging health issues. This document will help those responsible for
building maintenance in the evaluation of remediation plans. Contractors and
other professionals (e.g. industrial hygienists or other environmental
health and safety professionals) who respond to mold and moisture situations
in buildings, as well as members of the general public, also may find these
guidelines helpful. The information in these guidelines is intended only as
a summary of basic procedures and is not intended, nor should it be used, as
a detailed guide to mold remediation. These guidelines are subject to change
as more information regarding mold contamination and remediation becomes
available.
Mold Basics
Molds are part of the natural environment. Molds are
fungi that can be found anywhere - inside or outside - throughout the year.
About 1,000 species of mold can be found in the United States, with more
than 100,000 known species worldwide.
Outdoors, molds play an important role in nature by
breaking down organic matter such as toppled trees, fallen leaves, and dead
animals. We would not have food and medicines, like cheese and
penicillin, without mold.
Indoors, mold growth should be avoided. Problems may
arise when mold starts eating away at materials, affecting the look, smell,
and possibly, with the respect to wood-framed buildings, affecting the
structural integrity of the buildings.
Molds can grow on
virtually any substance, as long as moisture or water, oxygen, and an
organic source are present. Molds reproduce by creating tiny spores (viable
seeds) that usually cannot be seen without magnification. Mold spores
continually float through the indoor and outdoor air.
Molds are usually not a
problem unless mold spores land on a damp spot and begin growing. They
digest whatever they land on in order to survive. There are molds that grow
on wood, paper, carpet, foods and insulation, while other molds feast on the
everyday dust and dirt that gather in the moist regions of a building.
When excessive moisture
or water accumulates indoors, mold growth often will occur, particularly if
the moisture problem remains uncorrected. While it is impossible to
eliminate all molds and mold spores, controlling moisture can control indoor
mold growth.
All molds share the characteristic of being able to
grow without sunlight; mold needs only a viable seed (spore), a nutrient
source, moisture, and the right temperature to proliferate. This explains
why mold infestation is often found in damp, dark, hidden spaces; light and
air circulation dry areas out, making them less hospitable for mold.
Molds gradually damage
building materials and furnishings. If left unchecked, mold can eventually
cause structural damage to a wood framed building, weakening floors and
walls as it feeds on moist wooden structural members. If you suspect that
mold has damaged building integrity, consult a structural engineer or other
professional with the appropriate expertise.
Since mold requires water to grow, it is important to
prevent excessive moisture in buildings. Some moisture problems in buildings
have been linked to changes in building construction practices since the
1970s, which resulted in tightly sealed buildings with diminished
ventilation, contributing to moisture vapor buildup. Other moisture problems
may result from roof leaks, landscaping or gutters that direct water into or
under a building, or unvented combustion appliance. Delayed or insufficient
maintenance may contribute to moisture problems in buildings. Improper
maintenance and design of building heating/ventilating/air-conditioning
(HVAC) systems, such as insufficient cooling capacity for an air
conditioning system, can result in elevated humidity levels in a building.
Health Effects
Currently, there are no
federal standards or recommendations, (e.g., OSHA, NIOSH, EPA) for airborne
concentrations of mold or mold spores.
Scientific research on the relationship between mold exposures and health
effects is ongoing. This section provides a brief overview, but does not
describe all potential health effects related to mold exposure. For more
detailed information, consult a health professional or your state or local
health department.
There are many types of mold. Most typical indoor air
exposures to mold do not present a risk of adverse health effects. Molds can
cause adverse effects by producing allergens (substances that can cause
allergic reactions). Potential health concerns are important reasons to
prevent mold growth and to remediate existing problem areas.
The onset of allergic
reactions to mold can be either immediate or delayed. Allergic responses
include hay fever-type symptoms such as runny nose and red eyes.
Molds may cause
localized skin or mucosal infections but, in general, do not cause systemic
infections in humans, except for persons with impaired immunity, AIDS,
uncontrolled diabetes, or those taking immune suppressive drugs. An
important reference with guidelines for immuno-compromised individuals can
be found at the Centers for Disease Control and Prevention (CDC) website (www.cdc.gov).
Molds can also cause
asthma attacks in some individuals who are allergic to mold. In addition,
exposure to mold can irritate the eyes, skin, nose and throat in certain
individuals. Symptoms other than allergic and irritant types are not
commonly reported as a result of inhaling mold in the indoor environment.
Some specific species of
mold produce mycotoxins under certain environmental conditions. Potential
health effects from mycotoxins are the subject of ongoing scientific
research and are beyond the scope of this document.
Eating, drinking, and
using tobacco products and cosmetics where mold remediation is taking place
should be avoided. This will prevent unnecessary contamination of food,
beverage, cosmetics, and tobacco products by mold and other harmful
substances within the work area.
Prevention
Moisture control is the key to mold control. When
water leaks or spills occur indoors - act promptly. Any initial water
infiltration should be stopped and cleaned promptly. A prompt response
(within 24-48 hours) and thorough clean- up, drying, and/or removal of
water-damaged materials will prevent or limit mold growth.
Mold prevention tips
include:
·
Repairing plumbing leaks and leaks in the building structure
as soon as possible.
·
Looking for condensation and wet spots. Fix source(s) of
moisture incursion problem(s) as soon as possible.
·
Preventing moisture from condensing by increasing surface
temperature or reducing the moisture level in the air (humidity). To
increase surface temperature, insulate or increase air circulation. To
reduce the moisture level in the air, repair leaks, increase ventilation (if
outside air is cold and dry), or dehumidify (if outdoor air is warm and
humid).
·
Keeping HVAC drip pans clean, flowing properly, and
unobstructed.
·
Performing regularly scheduled building/ HVAC inspections and
maintenance, including filter changes.
·
Maintaining indoor relative humidity below 70% (25 - 60%, if
possible).
·
Venting moisture-generating appliances, such as dryers, to the
outside where possible.
·
Venting kitchens (cooking areas) and bathrooms according to
local code requirements.
·
Cleaning and drying wet or damp spots as soon as possible, but
no more than 48 hours after discovery.
·
Providing adequate drainage around buildings and sloping the
ground away from building foundations. Follow all local building codes.
·
Pinpointing areas where leaks have occurred, identifying the
causes, and taking preventive action to ensure that they do not reoccur.
Questions That
May Assist in Determining Whether a Mold Problem Currently Exists
·
Are building materials or furnishings visibly moisture
damaged?
·
Have building materials been wet more than 48 hours?
·
Are there existing moisture problems in the building?
·
Are building occupants reporting musty or moldy odors?
·
Are building occupants reporting health problems that they
think are related to mold in the indoor environment?
·
Has the building been recently remodeled or has the building
use changed?
·
Has routine maintenance been delayed or the maintenance plan
been altered?
Always consider
consulting a health professional to address any employee health concerns.
Remediation Plan
Remediation includes
both the identification and correction of the conditions that permit mold
growth, as well as the steps to safely and effectively remove mold damaged
materials.
Before planning the remediation assess the extent of
the mold or moisture problem and the type of damaged materials. If you
choose to hire outside assistance to do the cleanup, make sure the
contractor has experience with mold remediation. Check references and ask
the contractor to follow the recommendations in EPA’s publication, “Mold
Remediation in Schools and Commercial Buildings,” or other guidelines
developed by professional or governmental organizations.
The remediation plan
should include steps to permanently correct the water or moisture problem.
The plan should cover the use of appropriate personal protective equipment (PPE).
It also should include steps to carefully contain and remove moldy building
materials in a manner that will prevent further contamination. Remediation
plans may vary greatly depending on the size and complexity of the job, and
may require revision if circumstances change or new facts are discovered.
If you suspect that the
HVAC system is contaminated with mold, or if mold is present near the intake
to the system, contact the National Air Duct Cleaners Association (NADCA),
or 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, as it could spread
contamination throughout the building. If the water or mold damage was
caused by sewage or other contaminated water, consult a professional who has
experience cleaning and repairing buildings damaged by contaminated water.
The remediation
manager’s highest priority must be to protect the health and safety of the
building occupants and remediators. Remediators should avoid exposing
themselves and others to mold-laden dusts as they conduct their cleanup
activities. Caution should be used to prevent mold and mold spores from
being dispersed throughout the air where they can be inhaled by building
occupants. In some cases, especially those involving large areas of
contamination, the remediation plan may include temporary relocation of some
or all of the building occupants.
When deciding if
relocating occupants is necessary, consideration should be given to the size
and type of mold growth, the type and extent of health effects reported by
the occupants, the potential health risks that could be associated with the
remediation activity, and the amount of disruption this activity is likely
to cause. In addition, before deciding to relocate occupants, one should
also evaluate the remediator’s ability to contain/minimize possible
aerosolization of mold spores given their expertise and the physical
parameters of the workspace. When possible, remediation activities should be
scheduled during off hours when building occupants are less likely to be
affected.
Remediators,
particularly those with health related concerns, may wish to check with
their physicians or other health-care professionals before working on mold
remediation or investigating potentially moldy areas. If any individual has
health concerns, doubts, or questions before beginning a remediation/cleanup
project, he or she should consult a health professional.
Mold Remediation/Cleanup Methods
The purpose of mold
remediation is to correct the moisture problem and to remove moldy and
contaminated materials to prevent human exposure and further damage to
building materials and furnishings. Porous materials that are wet and have
mold growing on them may have to be discarded because molds can infiltrate
porous substances and grow on or fill in empty spaces or crevices. This mold
can be difficult or impossible to remove completely.
As a general rule, simply killing the mold, for
example, with biocide is not enough. The mold must be removed, since the
chemicals and proteins, which can cause a reaction in humans, are present
even in dead mold.
A variety of cleanup
methods are available for remediating damage to building materials and
furnishings caused by moisture control problems and mold growth. The
specific method or group of methods used will depend on the type of material
affected. Some methods that may be used include the following:
Wet Vacuum
Wet vacuums are vacuum
cleaners designed to collect water. They can be used to remove water from
floors, carpets, and hard surfaces where water has accumulated. They should
not be used to vacuum porous materials, such as gypsum board. Wet vacuums
should be used only on wet materials, as spores may be exhausted into the
indoor environment if insufficient liquid is present. The tanks, hoses, and
attachments of these vacuums should be thoroughly cleaned and dried after
use since mold and mold spores may adhere to equipment surfaces.
Damp Wipe
Mold can generally be
removed from nonporous surfaces by wiping or scrubbing with water and
detergent. It is important to dry these surfaces quickly and thoroughly to
discourage further mold growth. Instructions for cleaning surfaces, as
listed on product labels, should always be read and followed.
HEPA Vacuum
HEPA (High-Efficiency
Particulate Air) vacuums are recommended for final cleanup of remediation
areas after materials have been thoroughly dried and contaminated materials
removed. HEPA vacuums also are recommended for cleanup of dust that may have
settled on surfaces outside the remediation area. Care must be taken to
assure that the filter is properly seated in the vacuum so that all the air
passes through the filter. When changing the vacuum filter, remediators
should wear respirators, appropriate personal protective clothing, gloves,
and eye protection to prevent exposure to any captured mold and other
contaminants. The filter and contents of the HEPA vacuum must be disposed of
in impermeable bags or containers in such a way as to prevent release of the
debris.
Disposal of Damaged
Materials
Building materials and
furnishings contaminated with mold growth that are not salvageable should be
placed in sealed impermeable bags or closed containers while in the
remediation area. These materials can usually be discarded as ordinary
construction waste. It is important to package mold-contaminated materials
in this fashion to minimize the dispersion of mold spores. Large items with
heavy mold growth should be covered with polyethylene sheeting and sealed
with duct tape before being removed from the remediation area. Some jobs may
require the use of dust-tight chutes to move large quantities of debris to a
dumpster strategically placed outside a window in the remediation area.
Use of Biocides
The use of a biocide,
such as chlorine bleach, is not recommended as a routine practice during
mold remediation, although there may be instances where professional
judgment may indicate its use (for example, when immuno-compromised
individuals are present). In most cases, it is not possible or desirable to
sterilize an area, as a background level of mold spores comparable to the
level in outside air will persist. However, the spores in the ambient air
will not cause further problems if the moisture level in the building has
been corrected.
Biocides are toxic to animals and humans, as well as
to mold. If you choose to use disinfectants or biocides, always ventilate
the area, using outside air if possible, and exhaust the air to the
outdoors. When using fans, take care not to extend the zone of contamination
by distributing mold spores to a previously unaffected area.
Never mix chlorine bleach solution with other cleaning
solutions or detergents that contain ammonia because this may produce highly
toxic vapors and create a hazard to workers.
Some biocides are
considered pesticides, and some states require that only registered
pesticide applicators apply these products in schools, commercial buildings,
and homes. Make sure anyone applying a biocide is properly licensed where
required.
Fungicides are commonly
applied to outdoor plants, soil, and grains as a powder or spray. Examples
of fungicides include hexachlorobenzene, organomercurials,
pentachlorophenol, phthalimides, and dithiocarbamates.
Do not
use fungicides developed for outdoor use in any indoor application, as they
can be extremely toxic to animals and humans in an enclosed environment.
When you use biocides as
a disinfectant or a pesticide, or as a fungicide, you should use appropriate
PPE, including respirators. Always, read and follow product label
precautions. It is a violation of Federal (EPA) law to use a biocide in any
manner inconsistent with its label direction.
Mold Remediation Guidelines
This section presents
remediation guidelines for building materials that have or are likely to
have mold growth. The guidelines are designed to protect the health of
cleanup personnel and other workers during remediation. These guidelines are
based on the size of the area impacted by mold contamination. Please note
that these are guidelines; some professionals may prefer other remediation
methods, and certain circumstances may require different approaches or
variations on the approaches described below. If possible, remediation
activities should be scheduled during off-hours when building occupants are
less likely to be affected.
Although the level of
personal protection suggested in these guidelines is based on the total
surface area contaminated and the potential for remediator or occupant
exposure, professional judgment always should play a part in remediation
decisions. These remediation guidelines are based on the size of the
affected area to make it easier for remediators to select appropriate
techniques, not on the basis of research showing there is a specific method
appropriate at a certain number of square feet. The guidelines have been
designed to help construct a remediation plan. The remediation manager
should rely on professional judgment and experience to adapt the guidelines
to particular situations. When in doubt, caution is advised. Consult an
experienced mold remediator for more information.
Level I: Small Isolated Areas
(10 sq. ft or less) - e.g., ceiling tiles, small areas on walls.
·
Remediation can be conducted by the regular building
maintenance staff as long as they are trained on proper clean-up methods,
personal protection, and potential health hazards. This training can be
performed as part of a program to comply with the requirements of the OSHA
Hazard Communication Standard (29 CFR 1910.1200).
·
Respiratory protection (e.g., N-95 disposable respirator) is
recommended. Respirators must be used in accordance with the OSHA
respiratory protection standard (29 CFR 1910.134). Gloves and eye protection
should be worn.
·
The work area should be unoccupied. Removing people from
spaces adjacent to the work area is not necessary, but is recommended for
infants (less than 12 months old), persons recovering from recent surgery,
immune-suppressed people, or people with chronic inflammatory lung diseases
(e.g., asthma, hypersensitivity pneumonitis, and severe allergies).
·
Containment of the work area is not necessary. Dust
suppression methods, such as misting (not soaking) surfaces prior to
remediation, are recommended.
·
Contaminated materials that cannot be cleaned should be
removed from the building in a sealed impermeable plastic bag. These
materials may be disposed of as ordinary waste.
·
The work area and areas used by remediation workers for egress
should be cleaned with a damp cloth or mop and a detergent solution.
·
All areas should be left dry and visibly free from
contamination and debris.
Level II:
Mid-Sized Isolated Areas (10-30 sq. ft.)
– e.g., individual wallboard panels.
·
Remediation can be conducted by the regular building
maintenance staff. Such persons should receive training on proper clean-up
methods, personal protection, and potential health hazards. This training
can be performed as part of a program to comply with the requirements of the
OSHA Hazard Communication Standard (29 CFR 1910.1200).
·
Respiratory protection (e.g., N-95 disposable respirator) is
recommended. Respirators must be used in accordance with the OSHA
respiratory protection standard (29 CFR 1910.134). Gloves and eye protection
should be worn.
·
The work area should be unoccupied. Removing people from
spaces adjacent to the work area is not necessary, but is recommended for
infants (less than 12 months old), persons recovering from recent surgery,
immune-suppressed people, or people with chronic inflammatory lung diseases
(e.g., asthma, hypersensitivity pneumonitis, and severe allergies).
·
Surfaces in the work area that could become contaminated
should be covered with a secured plastic sheet(s) before remediation to
contain dust/debris and prevent further contamination.
·
Dust suppression methods, such as misting (not soaking)
surfaces prior to remediation, are recommended.
·
Contaminated materials that cannot be cleaned should be
removed from the building in a sealed impermeable plastic bag. These
materials may be disposed of as ordinary waste.
·
The work area and areas used by remediation workers for egress
should be HEPA vacuumed and cleaned with a damp cloth or mop and a detergent
solution.
·
All areas should be left dry and visibly free from
contamination and debris.
Level III: Large
Isolated Areas (30 –100 square feet) –
e.g., several wallboard panels.
Industrial hygienists or other environmental health
and safety professionals with experience performing microbial investigations
and/or mold remediation should be consulted prior to remediation activities
to provide oversight for the project.
The following procedures may be implemented depending
upon the severity of the contamination:
·
It is recommended that personnel be trained in the handling of
hazardous materials and equipped with respiratory protection (e.g., N-95
disposable respirator). Respirators must be used in accordance with the OSHA
respiratory protection standard (29 CFR 1910.134). Gloves and eye protection
should be worn.
·
Surfaces in the work area and areas directly adjacent that
could become decontaminated should be covered with a secured plastic sheet(s)
before remediation to contain dust/ debris and prevent further
contamination.
·
Seal ventilation ducts/grills in the work area and areas
directly adjacent with plastic sheeting.
·
The work area and areas directly adjacent should be
unoccupied. Removing people from spaces near the work area is recommended
for infants, persons having undergone recent surgery, immunesuppressed
people, or people with chronic inflammatory lung diseases. (e.g., asthma,
hypersensitivity pneumonitis, and severe allergies).
·
Dust suppression methods, such as misting (not
soaking) surfaces prior to mediation, are recommended.
·
Contaminated materials that cannot be cleaned should be
removed from the building in sealed impermeable plastic bags. These
materials may be disposed of as ordinary waste.
·
The work area and surrounding areas should be HEPA vacuumed
and cleaned with a damp cloth or mop and a detergent solution.
·
All areas should be left dry and visibly free from
contamination and debris.
Note: If abatement
procedures are expected to generate a lot of dust (e.g., abrasive cleaning
of contaminated surfaces, demolition of plaster walls) or the visible
concentration of the mold is heavy (blanket coverage as opposed to patchy),
it is recommended that the remediation procedures for Level IV be followed.
Level IV: Extensive
Contamination (greater than 100
contiguous square feet in an area).
Industrial hygienists or other environmental health
and safety professionals with experience performing microbial investigations
and/or mold remediation should be consulted prior to remediation activities
to provide oversight for the project.
The following procedures may be implemented depending
upon the severity of the contamination:
·
Personnel trained in the handling of hazardous materials and
equipped with:
o
Full face piece respirators with HEPA cartridges;
o
Disposable protective clothing covering entire body including
both head and shoes; and
o
Gloves.
·
Containment of the affected area:
o
Complete isolation of work area from occupied spaces using
plastic sheeting sealed with duct tape (including ventilation ducts/grills,
fixtures, and other openings);
o
The use of an exhaust fan with a HEPA filter to generate
negative pressurization; and
o
Airlocks and decontamination room.
·
If contaminant practices effectively prevent mold from
migrating from affected areas, it may not be necessary to remove people from
surrounding work areas. However, removal is still recommended for infants,
persons having undergone recent surgery, immune- suppressed people, or
people with chronic inflammatory lung diseases. (e.g., asthma,
hypersensitivity pneumonitis, and severe allergies).
·
Contaminated materials that cannot be cleaned should be
removed from the building in sealed impermeable plastic bags. The outside of
the bags should be cleaned with a damp cloth and a detergent solution or
HEPA vacuumed in the decontamination chamber prior to their transport to
uncontaminated areas of the building. These materials may be disposed of as
ordinary waste.
·
The contained area and decontamination room should be HEPA
vacuumed and cleaned with a damp cloth or mopped with a detergent solution
and be visibly clean prior to the removal of isolation barriers.
Personal
Protective Equipment (PPE)
Any remediation work
that disturbs mold and causes mold spores to become airborne increases the
degree of respiratory exposure. Actions that tend to disperse mold include:
breaking apart moldy porous materials such as wallboard; destructive
invasive procedures to examine or remediate mold growth in a wall cavity;
removal of contaminated wallpaper by stripping or peeling; using fans to dry
items or ventilate areas.
The primary function of
personal protective equipment is to prevent the inhalation and ingestion of
mold and mold spores and to avoid mold contact with the skin or eyes. The
following sections discuss the various types of PPE that may be used during
remediation activities.
Skin and Eye
Protection
Gloves protect the skin
from contact with mold, as well as from potentially irritating cleaning
solutions. Long gloves that extend to the middle of the forearm are
recommended. The glove material should be selected based on the type of
substance/ chemical being handled. If you are using a biocide such as
chlorine bleach, or a strong cleaning solution, you should select gloves
made from natural rubber, neoprene, nitrile, polyurethane, or PVC. If you
are using a mild detergent or plain water, ordinary household rubber gloves
may be used.
To protect your eyes,
use properly fitted goggles or a full face piece respirator. Goggles must be
designed to prevent the entry of dust and small particles. Safety glasses or
goggles with open vent holes are not appropriate in mold remediation.
Respiratory Protection
Respirators protect
cleanup workers from inhaling airborne mold, contaminated dust, and other
particulates that are released during the remediation process. Either a half
mask or full face piece air-purifying respirator can be used. A full face
piece respirator provides both respiratory and eye protection. Please refer
to the discussion of the different levels of remediation to ascertain the
type of respiratory protection recommended. Respirators used to provide
protection from mold and mold spores must be certified by the National
Institute for Occupational Safety and Health (NIOSH). More protective
respirators may have to be selected and used if toxic contaminants such as
asbestos or lead are encountered during remediation.
As specified by OSHA in
29 CFR 1910.134 individuals who use respirators must be properly trained,
have medical clearance, and be properly fit tested before they begin using a
respirator. In addition, use of respirators requires the employer to develop
and implement a written respiratory protection program, with
worksite-specific procedures and elements.
Protective Clothing
While conducting
building inspections and remediation work, individuals may encounter
hazardous biological agents as well as chemical and physical hazards.
Consequently, appropriate personal protective clothing (i.e., reusable or
disposable) is recommended to minimize cross-contamination between work
areas and clean areas, to prevent the transfer and spread of mold and other
contaminants to street clothing, and to eliminate skin contact with mold and
potential chemical exposures.
Disposable PPE should be
discarded after it is used. They should be placed into impermeable bags, and
usually can be discarded as ordinary construction waste. Appropriate
precautions and protective equipment for biocide applicators should be
selected based on the product manufacturer’s warnings and recommendations
(e.g., goggles or face shield, aprons or other protective clothing, gloves,
and respiratory protection).
Sampling for Mold
Is it necessary to
sample for mold? In most cases, if visible mold
growth is present, sampling is unnecessary. Air
sampling for mold may not be part of a routine assessment because decisions
about appropriate remediation strategies often can be made on the basis of a
visual inspection.
Your first step should
be to inspect for any evidence of water damage and visible mold growth.
Testing for mold is expensive, and there should be a clear reason for doing
so. In many cases, it is not economically practical or useful to test for
mold growth on surfaces or for airborne spores in the building. In addition,
there are no standards for “acceptable” levels of mold in buildings, and the
lack of a definitive correlation between exposure levels and health effects
makes interpreting the data difficult, if not impossible.
Testing is usually done to compare the levels and
types of mold spores found inside the building with those found outside of
the building or for comparison with another location in the building. In
addition, air sampling may provide tangible evidence supporting a hypothesis
that investigators have formulated. For example, air sampling may show a
higher concentration of the same species of mold when the HVAC is operating
than when it has been turned off. This finding may convince the
investigators that the mold is growing within, and being disseminated by,
the HVAC system. Conversely, negative results may persuade investigators to
abandon this hypothesis and to consider other sources of mold growth or
dissemination. If you know you have a mold problem, it is more important to
spend time and resources removing the mold and solving the moisture problem
that causes the moldy conditions than to undertake extensive testing for the
type and quantity of mold.
If you are in doubt
about sampling, consult an industrial hygienist or other environmental
health or safety professional with experience in microbial investigations to
help you decide if sampling for mold is necessary or useful, and to identify
persons who can conduct any necessary sampling. Due to the wide difference
in individual susceptibility to mold contamination, sampling results
sampling may have limited application. However, sampling results can be used
as a guide to determine the extent of an infestation and the effectiveness
of the cleanup. Their interpretation is best left to the industrial
hygienist or other environmental health or safety professional.
Sampling for mold should
be conducted by professionals with specific experience in designing
mold-sampling protocols, sampling methods for microbial contaminants, and
interpretation of results. For additional information on air sampling, refer
to the American Conference of Governmental Industrial Hygienists’ document,
“Bioaerosols: Assessment and Control.” In addition, sampling and analysis
should follow any other methods recommended by either OSHA, NIOSH, EPA, the
American Industrial Hygiene Association, or other recognized professional
guidelines. Types of samples can include: air samples, surface samples, bulk
samples, and water samples from condensate drain pans or cooling towers.
Microscopic
identification of the spores/ colonies requires considerable expertise.
These services are not routinely available from commercial laboratories.
Documented quality control in the laboratories used for analysis of the
bulk, surface, and other air samples is necessary. The American Industrial
Hygiene Association offers accreditation to microbial laboratories
(Environmental Microbiology Laboratory Accreditation Program (EMLAP)).
Accredited laboratories must participate in quarterly proficiency testing
(Environmental Microbiology Proficiency Analytical Testing Program (EMPAT)).
Remediation Equipment
There are various types
of equipment useful in mold assessment and remediation. Some of the more
common items include:
Moisture Meters
Moisture meters
measure/monitor moisture levels in building materials, and may be helpful
for measuring the moisture content in a variety of building materials
following water damage. They also can be used to monitor the progress of
drying damaged materials. These direct reading devices have a thin probe
that is inserted into the material to be tested or pressed directly against
the surface of the material. Moisture meters can be used on materials such
as carpet, wallboard, wood, brick, and concrete.
Humidity Gauges or
Meters
Humidity meters can be
used to monitor indoor humidity. Inexpensive (less than $50) models that
monitor both temperature and humidity are available.
Humidistat
A humidistat is a control device that can be connected
to an HVAC system and adjusted so that if the humidity level rises above a
set point, the HVAC system will automatically turn on and reduce the
humidity below the established point.
Boroscope
A boroscope is a hand-held tool that allows users to
see potential mold problems inside walls, ceiling plenums, crawl spaces, and
other tight areas. It consists of a video camera on the end of a flexible
“snake.” No major drilling or cutting of dry wall is required.
HVAC System Filter
High-quality filters
must be used in a HVAC system during remediation because conventional HVAC
filters are typically not effective in filtering particles the size of mold
spores. Consult an engineer for the appropriate filter efficiency for your
specific HVAC system, and consider upgrading your filters if necessary. A
filter with a minimum efficiency of 50 to 60% or a rating of MERV 8, as
determined by Test Standard 52.2 of the American Society of Heating,
Refrigerating and Air-Conditioning Engineers, may be appropriate.
Remember to change filters as appropriate, especially
following any remediation activities. Remove filters in a manner that
minimizes the reentry of mold and other toxic substances into the workplace.
Under certain circumstances, it may be necessary to wear appropriate PPE
while performing this task.
How Do You Know When You
Have Finished Remediation/Cleanup?
·
You must have identified and completely corrected the source
of the water or moisture problem.
·
Mold removal should be complete. Visible mold, mold-damaged
materials, and moldy odors should no longer be present.
·
Sampling, if conducted, should show that the level and types
of mold and mold spores inside the building are similar to those found
outside.
·
You should revisit the site(s) after remediation, and it
should show no signs of moldy or musty odors, water damage, or mold growth.
Conclusion
After correcting water or moisture infiltration, the
prompt removal of contaminated material and structural repair is the primary
response to mold contamination in buildings. In all situations, the
underlying cause of water accumulation must be rectified or the mold growth
will reoccur. Emphasis should be placed on preventing contamination through
proper building and HVAC system maintenance and prompt repair of water
damaged areas.
Effective communication with building occupants is an
essential component of all large-scale remediation efforts. The building
owner, management, and/or employer should notify occupants in the affected
area(s) of the presence of mold. Notification should include a description
of the remedial measures to be taken and a timetable for completion. Group
meetings held before and after remediation with full disclosure of plans and
results can be an effective communication mechanism. Individuals with
persistent health problems that appear to be related to mold exposure should
see their physicians for a referral to practitioners who are trained in
occupational/environmental medicine or related specialties and are
knowledgeable about these types of exposures.
References
American Conference of Governmental Industrial
Hygienists 1999. Bioaerosols Assessment and
Control
http://www.acgih.org
National Apartment Association
http://www.naahq.org
National Institute for Occupational Safety and Health
(NIOSH)
http://www.cdc.gov/niosh
National Multi-Housing Council
http://www.nmhc.org
The Building Owners and Managers Association
International (BOMA)
http://www.boma.org
New York City Department of Health & Mental Hygiene
Bureau of Environmental & Occupational Disease Epidemiology 2002.
Guidelines on Assessment and Remediation of Fungi in
Indoor Environments
http://www.nyc.gov/html/doh/html/epi/moldrpt1.html
United States Environmental Protection Agency, Office
of Air and Radiation, Indoor Environments Division 2001.
Mold Remediation in Schools and Commercial Buildings.
EPA 402-K-01-001
http://www.epa.gov/iaq/molds/graphics/moldremediation.pdf
Mold Resources List
Business owners who are
concerned about the cost of professional help can contact the OSHA
Consultation Project Office in their state for free consultation service.
Priority is given to businesses with fewer than 250 employees at a worksite,
with further consideration given to the severity of the worksite problem.
The Consultation Program can help the employer evaluate and prevent
hazardous conditions in the workplace that can cause injuries and illnesses,
including mold problems.
The following list of
resources includes information developed and maintained by public and
private organizations. However, OSHA does not control this information and
cannot guarantee the accuracy, relevance, timeliness, or completeness of
this outside information. Further, the inclusion of these resources is not
intended to endorse any views expressed, or products or services offered, by
the author of the reference or the organization operating the service
identified by the reference.
An Office Building Occupant’s Guide to IAQ
http://www.epa.gov/iaq/pubs/occupgd.html
Biological Contaminants
http://www.epa.gov/iaq/biologic.html
Building Air Quality Action Plan (For Commercial
Buildings)
http://www.epa.gov/iaq/largebldgs/actionpl.html
Floods / Flooding
http://www.epa.gov/iaq/pubs/flood.html
Indoor Air Quality (IAQ) Home Page
http://www.epa.gov/iaq
IAQ in Large Buildings/Commercial Buildings
http://www.epa.gov/iaq/largebldgs/
IAQ in Schools
http://www.epa.gov/iaq/schools
Mold Resources
http://www.epa.gov/iaq/molds/moldresources.html
Mold Remediation in Schools and Commercial Buildings
http://www.epa.gov/iaq/molds/mold_remediation.html
U.S. EPA IAQ Information Clearinghouse (IAQINFO)
Phone: (800)438-4318 or (703)356-4020
Fax: (703)356-5386
Email: iaqinfo@aol.com
Indoor air related documents, answers to Indoor Air
Quality (IAQ) questions, maintains listing of State IAQ contacts, and
regional EPA Contacts.
Air Conditioning Contractors of America (ACCA)
(703)575-4477
http://www.acca.org/index.html
Information on indoor comfort products and services.
American College of Occupational and Environmental
Medicine (ACOEM)
(847)818-1800
http://www.acoemprivatepractice.com/
Referrals to physicians who have experience with
environmental exposures.
American Conference of Governmental Industrial
Hygienists, Inc. (ACGIH)
(513)742-2020
http://www.acgih.org
Occupational and environmental health and safety
information.
American Industrial Hygiene Association (AIHA)
(703)849-8888
http://www.aiha.org
Information on industrial hygiene and indoor air
quality issues including mold hazards and legal issues.
American Society of Heating, Refrigerating and Air
Conditioning Engineers, Inc. (ASHRAE)
(800)527-4723
http://www.ashrae.org
Information on engineering issues and indoor air
quality.
Association of Occupational and Environmental Clinics
(AOEC)
(202)347-4976
http://www.aoec.org
Referrals to clinics with physicians, who have
experience with environmental exposures, include exposure to mold; maintains
a database of occupational and environmental cases.
Association of Specialists in Cleaning and Restoration
(ASCR)
(800)272-7012 or (410)729-3603
http://www.ascr.org/institutes
Carpet and Upholstery Cleaning Institute, Mechancial
Systems Hygiene Institute, National Institute of Disaster Restoration,
National Institute Rug Cleaning, Water Loss Institute referrals to
professionals.
American Academy of Allergy, Asthma & Immunology (AAAAI)
(800)822-2762
http://www.aaaai.org/
Physician referral directory, information on allergies
and asthma.
Asthma and Allergy Foundation of American (AAFA)
(800) 7ASTHMA (800)727-8462)
http://www.aafa.org
Information on allergies and asthma.
American Lung Association (ALA)
(800) LUNGUSA (800)586-4872)
http:// www.lungusa.org
Information on allergies and asthma.
Allergy and Asthma Network Mothers of Asthmatics (AANMA)
(800)878-4403 or (703)641-9595)
http://www.aanma.org
Information on allergies and asthma.
National Institute of Allergy and Infectious Diseases
(NIAID)
(301)496-5717
http://www.niaid.nih.gov
Information on allergies and asthma.
National Jewish Medical and Research Center
(800) 222LUNG (800)222-5864)
http://www.njc.org
Information on allergies and asthma.
Carpet and Rug Institute (CRI)
(800) 882-8846
http://www.carpet-rug.com
Carpet maintenance, restoration guidelines for
water-damaged carpet, other carpet-related issues.
Centers for Disease Control and Prevention (CDC)
(800)311-3435
http://www.cdc.gov
Information on health-related topics including asthma
molds in the environment, and occupational health. CDC is recognized as the
lead federal agency for protecting the health and safety of the American
people at home and abroad. It serves as the national focus for developing
and applying disease prevention and control, environmental health, and
health promotion and education activities.
Floods/Flooding
Federal Emergency Management Agency (FEMA)
(800)480-2520
http://www.fema.gov/mit
Publications on floods, flood proofing, etc.
University of Minnesota, Department of Environmental
Health and Safety
(612)626-5804
http://www.dehs.umn.edu/iaq/flood.html
Managing water infiltration into buildings.
Indoor Environmental Remediation Board (IERB)
(215)387-4097
http://www.ierb.org
Information on best practices in building remediation.
Institute of Inspection, Cleaning and Restoration
Certification (IICRC)
(360)693-5675
http://www.iicrc.org
Information on and standards for the inspection,
cleaning, and restoration industry.
International Sanitary Supply Association (ISSA)
(800)225-4772
http://www.issa.com
Education and training on cleaning and maintenance.
MidAtlantic Environmental Hygiene Resource Center (MEHRC)
(215)387-4096
http://www.mehrc.org
Indoor environmental quality training center giving
courses in building moisture and biocontamination, and managing and
operating facilities for good IAQ. Extensive courses given in IAQ.
National Air Duct Cleaners Association (NADCA)
(202)737-2926
http://www.nadca.com
Duct cleaning information.
National Institute of Building Sciences (NIBS)
(202)289-7800
http://www.nibs.org
Information on building regulations, science, and
technology.
National Institute for Occupational Safety and Health
(NIOSH)
(800) 35NIOSH (800)356-4674)
http://www.cdc.gov/niosh
Health and safety information with a workplace
orientation.
National Pesticide Information Center (NPIC)
(800)858-7378
http://npic.orst.edu/
Information on pesticides/antimicrobial chemicals,
including safety and disposal information.
New York Department of Health, Bureau of Environmental
and Occupational Disease Epidemiology, Guidelines on Assessment and
Remediation of Fungi in Indoor Environments.
(212)788-4290
http://www.ci.nyc.ny.us/html/doh/html/epi/moldrpt1.html
Occupational Safety and Health Administration (OSHA)
200 Constitution Avenue, NW
Washington, DC 20210
(800)321-OSHA (800)321-6742)
http://www.osha.gov
Information on worker safety and health, compliance
assistance, laws and regulations, cooperative programs, state programs,
statistics, and newsroom.
Sheet Metal and Air Conditioning Contractors’ National
Association (SMACNA)
(703)803-2980
http://www.smacna.org
Technical information on topics such as air
conditioning and air ducts. |