United States
Environmental Protection
Agency
Indoor Environments
Division (6604J)
Office of Air and Radiation
EPA-402-K-97-003
October 1997
An Office Building
Occupant's Guide to
Indoor Air Quality

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 A Summary of What You'll Learn Inside...

 What You Can Do to Improve the Indoor Air in Your Office:

     Do not block air vents or grilles.
     Comply with the office and building smoking policy.
     Water and maintain office plants properly.
     Dispose of garbage promptly and properly.
     Store food properly.
     Avoid bringing products into the building that could release harmful or
 bothersome odors or contaminants.
 •   Notify your building or facility manager immediately if you suspect an
 indoor air quality problem.

 If You Manage an Office:

 •   Maintain a good working relationship with building management on
 indoor environmental issues.
 •   Place office furniture and equipment with air circulation, temperature
 control, and pollutant removal functions of the heating, ventilating, and air
 conditioning (HVAC) system in mind.
 •   Coordinate with building management in instances when responsibilty
 for design, operation, and maintenance of the ventilation system is shared.
 •   Establish an effective smoking policy that protects nonsmokers from
 involuntary exposure to secondhand smoke.
 •  Avoid procedures and products that can cause indoor air quality
 problems.
 •  Integrate indoor air quality concerns into your purchasing decisions.
 •  Work with the building manager to ensure use of only necessary and
 appropriate pest control practices, and nonchemical methods where
 possible.
•   Work with building management and the contractor before you remodel
 or renovate to identify ways of keeping building occupant exposure to pol-
 lutants to a minimum and to ensure that the air distribution system is not
 disrupted.
•   Encourage building management to develop a preventive indoor air
 quality management  program following guidance issued by EPA and the
 National Institute for Occupational Safety and Health (NIOSH).
                 For sale by the U.S. Government Printing Office
        Superintendent of Documents, Mail Stop: SSOP, Washington, DC 20402-9328
                    ISBN 0-16-042729-0

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Contents


About This Booklet	 .3

Why is Indoor Air Quality Important?	4

Factors that Contribute to Indoor Air Quality,	5

Factors that Affect Occupant Comfort and Productivity.	8

Indoor Air Quality is a Shared Responsibility.	9

Things Everyone in the Building Can Do	 11

What the Office Manager/Tenant Can Do	12

What Building Facility Managers Can Do to Promote Good Indoor Air
      Quality.	15

If You Think Your Building Has an Indoor Air Quality Problem	17

For More Information	18

U.S. EPA Regional Indoor Air contacts	19

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About This Booklet

      This booklet is intended to help people who work in office
buildings learn about the factors that contribute to indoor air quality
and comfort problems and the roles of building managers and
occupants in maintaining a good indoor environment. Because
good indoor air quality depends on the actions of everyone in the
building, a partnership between building management and
occupants is the best way to maintain  a healthy and productive
work space.

      Relationships and procedures between management and
occupants will vary from building to building. Some buildings are
occupied entirely by the employees of the building owner, and in
most of these buildings, the responsibility for indoor air quality
management may be handled by a central department or office. In
other buildings, where one or more building occupants rent space
under separate leases, building management may have limited
control over the day-to-day activities in the leased space.
Likewise, the occupants of such buildings may have little control
over central building services such as  heating and cooling,
elevator services, housekeeping, and waste and pest
management.  For these reasons, occupants and management in
leased space buildings will need to closely coordinate their indoor
environmental management strategies.

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 Why is Indoor Air Quality Important?

       Indoor air quality is a major concern to businesses, building
 managers, tenants, and employees because it can impact the health,
 comfort, well being, and productivity of building occupants.

       Most Americans spend up to 90% of their time indoors and many
 spend most of their working hours in an office environment.  Studies
 conducted by the U.S. Environmental Protection Agency (EPA) and others
, show that indoor environments sometimes can have levels of pollutants
• that are actually higher than levels found outside.

       Pollutants in our indoor environment can increase the risk of ill-
 ness.  Several studies by  EPA, states, and independent scientific panels
 have consistently ranked  indoor air pollution as an important environmen-
 tal health problem. While most buildings do not have severe indoor air
 quality problems,  even well-run buildings can sometimes experience
 episodes of poor indoor air quality.

       A 1989 EPA Report to Congress concluded that improved indoor
 air quality can result in higher productivity and fewer lost work days.  EPA
 estimates that poor indoor air may cost the nation tens of billions of dol-
 lars each year in lost productivity and medical care.




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  Factors that Contribute to Indoor Air Quality

        Indoor air quality is not a simple, easily defined concept like a desk
  or a leaky faucet.  It is a constantly changing interaction of complex fac-
  tors that affect the types, levels, and importance of pollutants in indoor
  environments.  These factors include: sources of pollutants or odors;
  design, maintenance and operation of building ventilation systems; mois-
  ture and humidity; and occupant perceptions and susceptibilities.  In addi-
  tion, there are  many other factors that affect comfort or perception of
  indoor air quality.

        Controlling indoor air quality involves integrating three main
  strategies. First, manage the sources of pollutants either by removing
  them from the  building or isolating them from people through physical
  barriers, air pressure  relationships, or by controlling the timing of their
  use.  Second, dilute pollutants and remove them from the building
  through ventilation. Third, use filtration to clean the air of pollutants.

  Management of Pollutant Sources,  both Inside and Outside
  the Building

        Pollutants can  be generated by outdoor or indoor sources,  includ-
  ing building maintenance activities, pest control, housekeeping, renova-
  tion or remodeling, new furnishings or finishes, and building occupant
  activities.

I        One important goal of an indoor air quality program is to minimize
  people's exposure to  pollutants from these sources.  Some of the key
  pollutant categories include:

      • Biological contaminants.  Excessive concentrations of bacteria,
  viruses, fungi (including molds), dust mite  allergen, animal dander, and
  pollen may result from inadequate maintenance and housekeeping, water
  spills, inadequate humidity control, condensation, or may be brought into
  the building by occupants, infiltration, or ventilation air. Allergic responses
  to indoor biological pollutant exposures cause symptoms in  allergic indi-
  viduals and also play a key role in triggering asthma episodes for an esti-
  mated 15 million Americans.

      • Chemical pollutants.  Sources of chemical pollutants include
  tobacco smoke, emissions from products used in the building (e.g., office
  equipment; furniture,  wall and floor coverings; and cleaning and con-
  sumer products) accidental spill of chemicals, and gases such as carbon
  monoxide and nitrogen dioxide, which are products of combustion.

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    • Particles.  Particles are solid or liquid substances which are light
enough to be suspended in the air, the largest of which may be visible in
sunbeams streaming into a room. However, smaller particles that you
cannot see are likely to be more harmful to health. Particles of dust, dirt,
or other substances may be drawn into the building from outside and can
also be produced by activities that occur in buildings, like sanding wood
or drywall, printing, copying, operating equipment, and smoking.

Type of Pollutant

      Many different factors influence how indoor air pollutants impact
occupants. Some pollutants, like radon, are of concern because expo-
sure to high levels of the pollutant over long periods of time increases risk
of serious, life threatening illnesses, such as lung cancer.  Other contami-
nants, such as carbon monoxide at very high levels, can cause death
within minutes.  Some pollutants can cause both short and long term
health problems.  Prolonged exposure to environmental tobacco smoke
can cause lung cancer, and short term exposures can result in irritation
and significant respiratory problems for some people, particularly young
children.

      People can react very differently when exposed to the same
contaminants at similar concentrations.  For example, some people can
develop severe allergic reactions to biological contaminants to which
other people will not react.  Similarly, exposure to very low levels of
chemicals may be irritating to some people but not others.  For people
with asthma and other pre-existing conditions, exposure to irritants like
environmental tobacco smoke or gases or particles from various indoor
sources may cause more severe reactions than the same exposure would
in others.

Moisture and Humidity

      It is important to control  moisture and relative humidity in occupied
spaces. The presence of moisture and dirt can cause molds and other
biological contaminants to thrive.  Relative humidity levels that are too
high can contribute to the growth and  spread of unhealthy biological pol-
lutants, as can failure to dry water-damaged materials promptly (usually
within 24 hours) or to properly maintain equipment with water reservoirs
or drain pans (e.g., humidifiers, refrigerators, and ventilation equipment).
Humidity levels that are too  low, however, may contribute to irritated
mucous membranes, dry eyes, and sinus discomfort.

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Design, Maintenance and Operation of Building Ventilation Systems

      Maintaining good indoor air quality requires attention to the building's
heating, ventilation, and air conditioning (HVAC) system; the design and
layout of the space; and pollutant source management.  HVAC systems
include all of the equipment used to ventilate, heat, and cool the building; to
move the air around the building (ductwork); and to filter and clean the air.
These systems can have a significant impact on how pollutants are
distributed and removed. HVAC systems can even act as sources of
pollutants in some cases, such as when ventilation air filters become
contaminated with dirt and/or moisture and when microbial growth results
from stagnant water in drip pans or from uncontrolled moisture inside of air
ducts. Because of the HVAC system's importance, good indoor air quality
management includes attention to:

    • Ventilation system design.  The air delivery capacity of an HVAC
system is based in part on the projected number of people and amount of
equipment in a building.  When areas in a building are used differently than
their original purpose, the HVAC system may require modification to
accommodate these changes. For example,  if a storage area is converted
into space occupied by people, the HVAC system may require alteration to
deliver enough conditioned air to the space.

    • Outside air supply.  Adequate supply of outside air, typically
delivered through the HVAC system, is necessary in any office environment
to dilute pollutants that are released by equipment, building materials,
furnishings, products, and people. Distribution of ventilation air to occupied
spaces is essential for comfort.

    • Outdoor air quality. When present, outdoor air pollutants such as
carbon monoxide, pollen, and dust may affect indoor conditions when outside
air is taken into the building's ventilation system.  Properly installed and
maintained filters can trap many of the particles in this outdoor supply air.
Controlling gaseous or chemical pollutants may require more specialized
filtration equipment.

    • Space planning. The use and placement of furniture and equipment
may affect the delivery of air to an occupied space. For instance, the
placement of heat generating equipment, like a computer, directly under an
HVAC control device such as a thermostat may cause the HVAC system to
deliver too much cool air, because the thermostat senses that the area is too
warm.  Furniture or partitions that block supply or return air registers can
affect IAQ as well, and need to be positioned with attention to air flow.

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    • Equipment maintenance. Diligent maintenance of HVAC
equipment is essential for the adequate delivery and quality of building
air. All well-run buildings have preventive maintenance programs that
help ensure the proper functioning of HVAC systems.

    • Controlling other pollutant pathways. Pollutants can spread
throughout a building by moving through stairwells, elevator shafts, wall
spaces, and utility chases. Special ventilation or other control measures
may be needed for some sources.

                                                                                 ,,M^-   -1

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:Ğ[	i
                  Factors that Affect Occupant Comfort and Productivity

                        Besides the factors that directly impact the levels of pollutants  to
                  which people are exposed, a number of environmental and personal
                  factors can affect how people perceive air quality. Some of these factors
                  affect both the levels of pollutants and perceptions of air quality.
Odors
Temperature — too hot or cold
Air velocity and movement — too drafty or stuffy
Heat or glare from sunlight
Glare from ceiling lights, especially on monitor screens
Furniture crowding
Stress  in the workplace or home
Feelings about physical aspects of the workplace:  location,
work environment, availability of natural light, and the
aesthetics of office design, such as color and style.
Work space ergonomics, including height and location of
computer, and adjustability of keyboards and desk chairs
Noise and vibration levels
Selection, location, and use  of office equipment
                        Ask your supervisor or office manager who to talk with if you have
                  a concern about any of these factors.

     8

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 Indoor Air Quality is a Shared Responsibility

      Some of the factors that contribute to poor indoor air quality may
 originate from inadequate HVAC design. Some may be solely in the con-
 trol of the building management, such as maintenance of the HVAC sys-
 tem and the amount of outside air being mechanically brought into the
 building. Others are largely in the control of building tenants and occu-
 pants, such as materials used in renovations and products and furnish-
 ings brought into or used in the building by occupants. Some, like cleanli-
 ness and general housekeeping of the building, require the cooperation
 of both the building management as well as all of the individuals who
 work in the building. For these reasons, indoor air quality is a shared
 responsibility.

      Good indoor air quality management practices can make a big
 difference. However, some factors, like reactions to  indoor air contami-
 nants among highly susceptible individuals, or the quality of the outside
 air, may not be within anyone's immediate control. It is also important to
 remember that any building, no matter how well operated, may  experi-
 ence periods of unacceptable indoor air quality due to equipment break-
 down, inadequate maintenance, or in some cases, the actions of building
 occupants.

      It is also important to keep in mind that many perceived indoor air
 quality problems are often comfort problems, such as temperature,
 humidity, or air movement in the space being too low or too high. In addi-
 tion, many symptoms, such as headaches, can have causes that are not
 related to factors in the building.

 The Good News...

      Even though the factors that affect the quality of the indoor
 environment are numerous, the good news is that most indoor environ-
 mental problems can be prevented or corrected easily and  inexpensively
through the application of common sense and vigilance on the part of
everyone in the building.  Success depends on cooperative actions taken
by building management  and occupants to improve and maintain indoor
air quality.  By becoming  knowledgeable about indoor air quality, tenants
and occupants are in a good position to help building managers maintain
a comfortable and healthy building environment.  Work with management
any time you:


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-     -
                    • Identify or suspect an indoor air problem
                    • Need cleaning and maintenance service
                    • Plan to install new office equipment
                    • Plan for renovations and/or remodeling with a professional interior
                           designer and/or an architect
                    • Experience leaks, spills, or accidents
   10

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Things Everyone in the Building Can Do

      All of the occupants of a building can have a great influence on
indoor air quality.  Everyday activities like heating food in a microwave
and using the photocopier can generate odors and pollutants. By being
aware of indoor air issues,  occupants can help prevent problems. Here
are some things you can do:

•  Do not block air vents  or grilles.  Keep supply vents or return air
grilles unblocked, so you won't unbalance the HVAC system or affect the
ventilation of a neighboring office. Furniture, boxes or other materials
near supply vents or return air grilles may also affect air flow.  Follow your
office's procedures to notify building management if your space is too hot,
too cold, stuffy or drafty.

•  Comply  with the office and building smoking policy. Smoke in
designated  areas only.

•  Clean up all water spills promptly, water and maintain office
plants properly and report water leaks right away.  Water creates a
hospitable environment for  the growth of micro-organisms such as molds
or fungi. Some of these microbes, if they become airborne, can cause
health problems.

•  Dispose of garbage promptly and properly. Dispose of garbage in
appropriate containers that are emptied daily to prevent odors and
biological contamination.

•  Store food properly.  Food attracts pests. Some foods, if left
unrefrigerated, can spoil and generate unpleasant odors.  Never store
perishable food products in your desk or on shelves.  Refrigerators should
be cleaned  on  a regular basis to prevent odors.  Keep kitchens and dining
areas clean and sanitize as necessary to prevent pests and maintain
hygiene.

•  Notify your building or facility manager immediately if you sus-
pect an IAQ problem. This helps management determine the cause of
the problem quickly so that a timely solution can be reached.
                                                                             11

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What the Office Manager/Tenant Can Do

      In leased space, the office manager or other person responsible
for office policies and/or relations with the property owner is often in a
position to directly and significantly impact indoor air quality in the space.
For some businesses,  responsibility for dealing with air quality issues may
involve more than one  person. The office manager should follow the
business's internal procedures in dealing with the building management.
Some of the things this person can do to improve indoor air quality
include:

• Maintain a good working relationship with building management
on indoor environmental issues. Cooperative  efforts are the best way
to solve many indoor air quality problems. Follow your internal guidelines
to ensure that building  facility management is informed of, and involved
in, all indoor air quality issues. Be as knowledgeable as  possible when
dealing with building management on indoor air issues.

• Place office furniture, partitions, and equipment with air circula-
tion, temperature control, and pollutant removal functions of the
HVAC system in mind. Make sure air supply vents and return grilles are
not blocked by furniture or equipment.  Computers and other heat-produc-
ing  equipment placed near or under an HVAC sensor device system can
trigger cooling, even if the actual temperature for  occupants is cool. Place
such equipment away from  HVAC sensors to avoid this kind of situation.

• Coordinate with building management in instances when
responsibility for design,  operation, and maintenance of the HVAC
system is shared. Sometimes the portion of the HVAC system servicing
a leased space is the responsibility of the tenant. In such cases, work
closely with building management to ensure that all parts of the building
are receiving optimal service from the system. Ensure that filters in win-
dow air conditioners and perimeter heating and cooling units are changed
frequently.

• Establish an effective smoking policy. Most of us today are aware
of the health risks of smoking, not only to smokers, but to those who are
exposed to secondhand smoke. In addition, environmental tobacco
smoke in a building can increase costs for maintaining the ventilation sys-
tem and for cleaning and replacing smoke-soiled furnishings and mater-
ials. Establish a  smoke-free policy in the space under your control or
work with building management to design properly ventilated smoking
rooms that don't  allow  smoke to circulate through the central ventilation
system or to adjoining  spaces.
         12

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• Avoid procedures and products that can cause problems.  Many
common products used in offices, like solvents, adhesives, cleaners, and
pesticides can give off pollutants and odors, as can office equipment
such as copiers, printers, and fax machines.  If any of these items are
used in the office environment, adequate and sometimes separate venti-
lation should be provided.  If your organization engages in activities that
may generate pollutants, such as photographic or printing processes,
exhaust ventilation will be especially important. Pollutants and odors
(which may or may not indicate a health concern) generated in your
space may not only bother those in the immediate area, but may enter
the building ventilation system and cause problems for other tenants in
other  parts of the building.

• Integrate indoor air quality concerns into your purchasing
decisions. Take steps to reduce exposures to contaminants from clean-
ing products, and from new furnishings and building materials, when
odors and chemical emissions are  usually highest.  Ask the designers,
suppliers, and manufacturers to provide information on chemical emis-
sions  from products and any potential associated respiratory hazards.
While emissions information may not yet be available for many products,
many product manufacturers are starting to do emissions testing.  The
more consumers request such information, the sooner it will become
widely available.

• Work with the building owner or manager to ensure use of only
necessary and appropriate pest control  practices, and non-chemical
methods where possible.  Pesticides can contribute to poor indoor air
quality and can cause serious health  effects when used improperly.
Unacceptable levels of pest activity and damage should be prevented by
the most economical means and with the least possible hazard to people,
property, and the environment.  For example, if roaches are a problem,
seal their entry points and properly store and dispose of food as part of a
long term control strategy.  If a chemical pesticide is selected, it should be
used in strict accordance with label directions. To reduce airborne expo-
sure to pesticides, consider using baits to kill pests instead of spraying.
Work with building management to select the most appropriate pesticide
to achieve your purpose, and do not purchase or  use more than needed.
                                                                             13

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             • Work with building management and contractors before you con-
             duct remodeling or renovation activities to identify ways of keeping
             exposure to pollutants to a minimum.
             Properly isolating the area to be remodeled or renovated from other
             spaces and the HVAC systems, and scheduling these activities for
             evenings and weekends if possible, can go a long way toward minimizing
             potential occupant problems. If the renovation work is contracted through
             you, ensure that the architect or interior designer and contractor are
             made aware, in advance, of the practices and procedures to be used dur-
             ing construction activities. If possible, try to arrange for plastic wrappings
             to be removed  from partitions, carpet rolls,  and other new materials
             before they are brought into the space. Ask to have the materials aired
             out in a clean,  dry location outside the building for a few days before
             installation. This can significantly reduce chemical emissions and odors
             inside the building.

             • Encourage building management to obtain and use the joint
             EPA/NIOSH guidance document entitled: Building Air Quality: A
             Guide for Building Owners and Facility Managers.  EPA and the
             National Institute for Occupational Safety and Health (NIOSH) have pub-
             lished comprehensive guidance for building owners and managers to help
             them prevent and solve indoor air quality problems. Ensuring that your
             building management is knowledgeable about and committed to manage-
             ment of indoor  air quality issues is an essential first step in preventing
             and fixing indoor air problems.
14

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What Building Facility Managers Can Do to Promote Good
Indoor Air Quality

      As an occupant of an office building, understanding the role of the
building management in maintaining a healthy and comfortable indoor
environment is an important step in understanding how you can fit into
the picture.  EPA and NIOSH recommend that every building manager
obtain and use the Building Air Quality guidance (see page 18) to:

• Designate an Indoor Air Quality Representative, who serves as the
contact for indoor environment issues.  The IAQ representative should
be accountable for the quality of the indoor environment and should have
the authority, knowledge, and  training to oversee or carry out the follow-
ing steps in a good indoor air  quality management plan:

• Assess the current condition of the indoor air in the building by:
   — identifying  and reviewing records pertaining to the HVAC design
   and operation
   — developing an indoor air profile of the building, identifying potential
   pollutant sources, if feasible

• Address any existing and  potential indoor air quality problems.

• Educate building staff about indoor air quality management by:
   — providing training opportunities
   — establishing clear  pollutant source management policies

• Operate and maintain the  building and ventilation system for good
indoor air by:
   — establishing or reinforcing standard operating and maintenance procedures
   — responding quickly to leaks, floods, and other accidents that occur
   in buildings to prevent indoor air quality problems from developing

• Manage potential pollutant sources such as:
   — smoking
   — remodeling and renovation materials and furnishings
   — housekeeping and pest  control products
   — exhaust fumes from loading docks or garages

• Communicate with tenants and occupants about their roles in
maintaining good indoor air quality.
                                                                           15

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             • Establish clear procedures for responding to indoor air-related
             complaints.

             • Keep a record of reported health complaints to aid in solving
             indoor air-related problems.  This will help improve the chances of cor-
             rectly diagnosing and then fixing problems, especially if a pattern in com-
             plaints can be detected.
16

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If You Think Your Building Has an Indoor Air Quality
Problem...

      If you or others at your office are experiencing health or comfort
problems that you suspect may be caused by indoor pollution, you can:

• Inform the building management of your concerns through your
usual and proper channels.

• Talk with your doctor or other health care provider, and report your
problems to the company physician, nurse, or health and safety
officer. Ask that person if you should call your state or local health
department to discuss your symptoms and possible causes.

• Cooperate with management during any indoor air quality
investigation to aid the sometimes difficult process of identifying and
solving problems.
                                                                         17

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            For More Information...

                 There are many sources of additional information on indoor air
            quality in offices, homes, and schools and what people can do to ensure
            that their indoor environment is a healthy one.  To obtain a list of available
            publications, contact EPA's:

                   Indoor Air Quality Information  Clearinghouse
                                    800438-4318
                                    P.O. Box 37133
                              Washington, DC 20013-7133
                                    202484-1307
                                   FAX 202 484-1510
                                e-mail: iaqinfo@aol.com
                 Visit EPA's Indoor Air Quality Home Page on the
                                  World Wide Web:

                                 www.epa.gov/iaa/
                   Building Air Quality: A Guide for Building Owners and
                                   Facility Managers
                                    is available from:

                              Superintendent of Documents
                                    PO Box 371954
                                Pittsburgh, PA 15250-7954
                         Order #: S/N 055-000-00390-4; Price $24.
18
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    US EPA Regional Indoor Air Contacts
US EPA Region 1
JFK Federal Building (ATO)
Boston, MA 02203-2211
Phone (617) 565-3232
Fax (617) 565-4940
 US EPA Region 6
 1445 Ross Ave.(6PD-T))
 Dallas, TX 75202-2733
 Phone (214) 665-7547
 Fax (214) 665-6762
US EPA Region 2, (AWM-RAD)
290 Broadway, 28th Floor
New York, NY 10007-1866
Phone (212) 637-4005
Fax (212) 637-4942
US EPA Region 3
(3AT32)
841 Chestnut Building
Philadelphia, PA 19107
Phone (215) 566-2083
Fax (215) 566-2134
US EPA Region 4
100 Alabama Street, SW
Atlanta, GA 30303-3104
Phone (404) 562-9143
Fax (404) 562-9095
US EPA Region 5
Mail Code (AE-17J)
77 West Jackson Blvd.
Chicago, IL 60604-3590
Phone (312) 886-6053
Fax (312) 353-8289
US EPA Region 7
726 Minnesota Ave.
Kansas City, KS66101
Phone (913) 551-7604
Fax (913) 551-7065
US EPA Region 8
(P2-TX)
999 18th Street, Suite 500
Denver, CO 80202-2466
Phone (303) 312-6024
Fax (303) 312-6044
US EPA Region 9, (Air-6)
75 Hawthorne Street
San Francisco, CA 94105
Phone (415) 744-1132
Fax (415) 744-1073
US EPA Region 10
(OAQ-107)
1200 Sixth Avenue
Seattle, WA 98101
Phone (206) 553-2589
Fax (206) 553-0110
                                                                                 19

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