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Indoor Air Quality


									Indoor Air Quality

                                                    exposures cause symptoms in allergic
    Indoor Air Quality (IAQ) Facts                  individuals and also play a key role in
In “An Introduction to Indoor Air Quality”,         triggering asthma episodes for an
on EPA’s Indoor Air Quality Program web             estimated 15 million Americans. Molds
site:                                               are a category of fungi with an estimated
  Indoor air is often more polluted than
                                                    20,000 species worldwide. Fungi survive
    outdoor, sometimes as much as 25%               by digesting plant and animal-based
    more polluted, and occasionally more            material specifically the starches and
    than 100 times higher.                          sugars stored in wood or paper. Mold
  Americans spend approximately 90%
                                                    spores are found almost everywhere and
    of their time indoors.                          given the right surface, temperature and
  Sick Building Syndrome occurs in
                                                    moisture can germinate and establish
    approximately 30% of buildings,                 colonies very quickly. Molds can make
    including both new and renovated                people very sick, degrade building
    buildings. Sick Building Syndrome, as           materials, and can cause structural
    defined by the EPA, is a term that              damage to buildings.
    refers to a set of symptoms that affect
    some number of building occupants               Chemical Pollutants
    during the time they spend in the
                                                    Sources of chemical pollutants include
    building and diminish or go away
                                                    tobacco smoke, emissions from products
    during periods when they leave the
                                                    used in the building (e.g. office
    building. Cannot be traced to specific
                                                    equipment; furniture, wall and floor
    pollutants or sources within the
                                                    coverings; and cleaning and consumer
                                                    products) accidental spill of chemicals,
  Lost productivity costs billions of
                                                    and gases such as carbon monoxide and
    dollars annually.
                                                    nitrogen dioxide, which are products of
  Indoor air pollution is one of the top
                                                    combustion. Noteworthy are Volatile
    five environmental risks to public
                                                    Organic Compounds (VOCs). VOCs are
                                                    compounds that vaporize (become a gas) at
                                                    room temperature. Common sources
Types of Indoor Air Contaminants                    which may emit VOCs into indoor air
                                                    include housekeeping and maintenance
The following definitions are from the              products, and building and furnishing
EPA’s IAQ Program Glossary:                         materials. In sufficient quantities, VOCs
Biological Contaminants                             can cause eye, nose, and throat
                                                    irritations, headaches, dizziness, visual
Excessive concentrations of bacteria,               disorders, memory impairment; some are
viruses, fungi (including molds), dust mite         known to cause cancer in animals; some
allergen, animal dander, and pollen may             are suspected of causing, or are known to
result from inadequate maintenance and              cause, cancer in humans. At present, not
housekeeping, water spills, inadequate              much is known about what health effects
humidity control, condensation, or may be           occur at the levels of VOCs typically found
brought into the building by occupants,             in public and commercial buildings. Heavy
infiltration, or ventilation air. Allergic          Metals; Airborne Lead and Mercury
responses to indoor biological pollutant

    California Sustainable Design             6.1
                                                                 Indoor Air Quality

Vapor. Lead toxicity can cause acute
illness and cognitive and developmental             Notes:
deficits in children. Latex paints that
contain phenyl mercuric acetate (a
preservative that prolongs shelf life) can
expose persons to mercury. Note: since
the mid 1990’s PMA has been prohibited
in newly manufactured paints.

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.

Sources of IAQ Problems
Potential sources of indoor air quality
problems inside the building include:
  HVAC system related problems such
   as improper air balance, dysfunctional
   supply and exhaust systems,
   malfunctioning controls, dirty cooling

  Dust Accumulated Inside a Mechanical Duct

                                              6.2            California Sustainable Design
Indoor Air Quality

   Human activities such as personal                strategies that cover areas including
    activities; housekeeping activities; and         selection of materials, design of the
    maintenance activities                           envelope, design, sizing and placement of
   Building furnishings including the               the Heating Ventilation and Air
    collection of dust or fibers; or the             Conditioning (HVAC) equipment and
    release of chemicals                             ductwork, appropriate construction
   Unsanitary conditions or water                   practices and maintenance and repair
    damage                                           schedules in building operations. It is
   Other sources include accidental                 difficult, if not impossible, to eliminate all
    events                                           sources of IAQ problems. Therefore, it is
   Inadequate ventilation of special use            important to reduce potential IAQ
    areas such as smoking lounges or                 problems through proper ventilation and
    food preparation areas, or copy                  regular maintenance practices.
   Dust and particles from renovation               Designing for good IAQ includes:
                                                     1. Material Selection
                                                     Many building materials contain volatile
                                                     organic components and other
Sources outside building include:
                                                     components that are, or may be,
  Pollen, dust, sprayed pesticides,
                                                     hazardous to human health. Selecting
   smoke or industrial pollutants
                                                     low-emitting materials and furniture
  Emissions from nearby sources, such
                                                     reduces the amount of toxins being
   as loading docks or vehicle exhaust
                                                     brought into the building. Other ideas
  Soil gasses such as radon or
                                                       Consider non-paper faced gypsum
  Moisture or standing water
                                                       Use entrance mats to remove
Symptoms of IAQ Problems                                 pollutants before an occupant enters a
There are many symptoms of indoor air                    building
quality problems. Immediate effects                    Specify low-emitting materials
include irritation of the eyes, nose, and              Avoid vinyl wall covering on exterior
throat, headaches, dizziness, and fatigue.               walls
Symptoms of some diseases may also                   Sustainable Material Resources
show up, such as asthma. Long-term                   The State of California has published
effects include respiratory diseases, heart          several documents, including
disease, and cancer.                                 Environmental Specifications for Office
                                                     Furniture Systems
Designing for Good IAQ                               and Reducing Occupant Exposure to
There are many strategies that can be                Volatile Organic Compounds from Office
used to reduce the chances of indoor air             Building Construction Materials: Non-
quality problems.                                    Binding Guidelines.
Source Control refers to reducing                    Other sources of low-emission standards
potential sources of IAQ problems.                   are:
Potential problems can be avoided via                 1. California’s Indoor Air Quality
                                                         Specifications as listed in Section

 California Sustainable Design                 6.3
                                                                  Indoor Air Quality

     1350 of the Specifications for the
     Capitol Area East End project.                  Notes:
2.   Adhesives: South Coast Air Quality
     Management District Rule #1168
3.   Paints and Coatings: Green Seal
4.   Carpet: Carpet and Rug Institute
     Green Label Indoor Air Quality Test

2. Envelope Design Ideas
  Provide drainage tile at foundation
    footings with a minimum slope of ½”
    per 10 ft.
  Provide polyethylene vapor retarder
    under floor slabs
  Locate ducts within the conditioned
    envelope to reduce the likelihood of
    moisture condensating on cold
  To the extent possible, use exterior
    wrap for duct insulation

3. System Design
Some of the key ventilation issues that
influence indoor air quality include:
  Ventilation effectiveness. Ventilation
     effectiveness refers to how well air
     changes occur throughout a building.
  Air changes. The number of air
     changes required in various building
     and room types is typically dictated by
  Location of air intakes. The location of
     air intakes can impact indoor air
     quality. The CA LEED Supplement
     suggests locating a building’s outdoor
     air intakes at least 25 feet from
     potential and existing sources of
  Duct insulation. To the extent
     possible, use exterior wrap for duct
     insulation, taking into consideration

                                               6.4            California Sustainable Design
Indoor Air Quality

    sound attenuation requirements. Avoid               and moist air from leaking into a wall
    oversizing the AC equipment as that                 or ceiling cavities.
    will reduce dehumidification                       Occupant Protection. If building is
    performance of the system.                          partially occupied prevent air from the
                                                        working areas from moving into the
                                                        occupied areas. Using the air
4. Construction Practice Ideas
                                                        distribution system, flush out work
The air quality of a renovated or new
                                                        area spaces prior to occupancy
building may be compromised by poor
                                                       Sequencing of Installation. If products
construction practices. One of the most
                                                        such as carpet and ceiling tiles are
widely recognized standards for good
                                                        installed before wet products such as
indoor air quality is the Sheet Metals and
                                                        paint, the carpet and tiles may absorb
Air Conditioning Contractors Association’s
                                                        paint emissions. These emissions may
(SMACNA) Guidelines for Occupied
                                                        then be released into the indoor
Buildings Under Construction, 1995.
                                                        environment over long periods of time.
SMACNA addresses:
                                                       Protection of materials. Keep building
                                                        materials off the ground and under
HVAC Protection. HVAC equipment                         cover
should be protected from dust and odors.
                                                    5. Operational Practice Ideas
Protection of the return side, supply side,
                                                      Regularly clean and replace air filters
and central filtration should be addressed.
                                                      Establish a vacuuming schedule for
Source Control. This includes addressing
                                                        installed carpets based upon traffic
pollution that can be controlled at the
source, such as product substitutions, use
                                                      Use cleaning agents on the basis of
of construction equipment, demolition
practices, exhausting work areas, and air
                                                      Clean exposed surfaces and furniture
Housekeeping. Surfaces should be kept
                                                      Develop a comprehensive program of
clean and dry. Non-toxic cleaning
                                                        integrated pest management,
products should also be used where
                                                        minimizing or eliminating the use of
                                                        chemical pesticides
Pathway Interruption. In occupied
                                                      Locate equipment with exhausts away
spaces, construction practices should
                                                        from areas where they will
include preventing air movement from the
                                                        compromise ventilation of buildings.
work area to occupied areas.
Scheduling. Especially in renovation
                                                    Investigating IAQ
projects, scheduling of work and occupant
movement is critical.                               Methods used in an IAQ investigation may
Specific construction practices that help             Identification of pollutant sources

prevent degradation of IAQ include:                   Evaluation of HVAC system
                                                      Observation of work practices

   HVAC Protection. Seal exhaust fan                 Measurement of contamination levels

    penetrations and ducts to keep dust                 and employee exposure

 California Sustainable Design                6.5
                                                                 Indoor Air Quality

   Medical testing or physical
    examinations                                    Notes:
   Employee interviews
   Review of records of medical tests, job
    histories and injuries and illnesses

One good resource is the EPA’s Building
Air Quality: A Guide for Building Owners
and Facility Managers (December 1991).
Because many indoor air quality problems
are best resolved by responsible
government agencies at the State and
local level, EPA has developed both a live
instructional course on indoor air quality
issues, entitled Orientation to Indoor Air
Quality, and a self-paced learning module
entitled Introduction to Indoor Air Quality
(April 1991) for these audiences.

Benefits of Eliminating IAQ
Potential benefits of taking steps to avoid
any indoor air quality problems include:
  Reduced liability risk
  Reduced insurance premiums
  Improved occupant health
  Increased productivity/reduced

The Scoping Study on the Costs of Indoor
Air Quality Illnesses: An Insurance Loss
Reduction Perspective, written by Allan
Chen and Edward L. Vine of Ernest
Orlando Lawrence Berkeley National
Laboratory, notes that “the incidence of
commercial buildings with poor indoor air
quality (IAQ), and the frequency of
litigation over the effects of poor IAQ is
increasing. If so, these increases have
ramifications for insurance carriers, which
pay for many of the costs of health care
and general commercial liability”….”The
literature search and discussions with
insurance and risk management
professionals reported in this paper turned

                                              6.6            California Sustainable Design
Indoor Air Quality

up little specific information about the            was filed by the occupants against the
costs of IAQ-related problems to                    architects, general contractors and HVAC
insurance companies. However, those                 contractors, suggesting that their illnesses
discussions and certain articles in the             were due to the design and the presence
insurance industry press indicate that              of VOCs. Yet another lawsuit was filed by
there is a strong awareness and growing             the county against the architects and
concern over the “silent crisis” of IAQ and         contractors. This suit asked for $3 million
its potential to cause large industry               for fixing the ventilation system and
losses, and that a few companies are                another $1 million for reimbursement of
taking steps to address this issue”.                worker’s claims.
In the Report to Congress on Indoor Air
Quality, 1989, it was noted that “It is             The final verdict was that the County’s
generally agreed that poor indoor air can           operation of the ventilation system was
adversely affect employee health and                the problem. The County received no
productivity. These costs to industry have          money for damages. The individual suits
been estimated to be in the "tens of                were settled out of court. Millions of
billions of dollars per year".                      additional dollars were spent on
                                                    investigations, legal fees, renovation, and
                                                    occupant compensation.
Examples of IAQ Liability
The EPA Headquarters located in the
Waterside Mall in Washington, DC was
renovated in 1987-1988. Five employees              i
                                                      This manual is being developed as part of a
sued the Waterside Mall operator for
                                                    ten-point plan to implement the Governor's
alleged exposure to organics from new               sustainable building goal as outlined in
carpet that was installed during the                Executive Order D-16-00 and the report
renovation. The employees cited                     Building Better Buildings: A Blueprint for
symptoms including cough, scratchy                  Sustainable State Facilities (Blueprint). Task 7
throat, sinus infections, fatigue and               of the Blueprint calls for developing
dizziness. The jury awarded nearly $1               sustainable building technical assistance and
million to the defendents.                          outreach tools, including a training program for
                                                    state departments, as well as local
Law enforcement and judicial staff                  government and private sector partners. This
                                                    manual was developed by DGS, the
occupied the new DuPage County
                                                    Sustainable building task force, and CIWMB
Courthouse in DuPage, IL in 1991. Over              as one component of the sustainable building
400 occupants soon began to suffer                  training program for state departments. This
headaches, nausea, dizziness, and                   document will be undergoing constant revision
respiratory irritation. In March of 1992,           as other deliverables outlined in the Blueprint
several employees were removed by                   are completed and technological and process
ambulance and the building was                      breakthroughs advance the rapidly emerging
evacuated. A number of lawsuits followed.           field of sustainable design.
First, occupants filed a suit against
DuPage County asking for closure of the
building. The building did close in
September of 1992 so that the ventilation
system could be rebuilt. A second lawsuit

 California Sustainable Design                6.7

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