United States
Environmental Protection
Agency
& EPA
Office of Research
and Development
Research Triangle Park, NC 27711
EPA/600/N-95/007 Fall/Winter 1995
Inside I A Q
EPA's Indoor Air Quality Research Update
We Apologize for the delay...
Due to the printing and distribution
moratorium imposed while EPA was
operating under continuing resolu-
tions, we were unable to distribute
this Fall/Winter 1995 issue as
originally scheduled.
In This Issue Page
Evaluation of an IAQ Source Management
Strategy for a Large Building 1
EPA Examines Indoor Emissions
from Conversion Varnishes 2
Review of Concentration Standards and
Guidelines for Fungi in Indoor Air 4
Two Case Studies Evaluating HVAC
Systems as Sources of Bioaerosols 4
Effect of Ventilation on Radon Levels
in a Municipal Office Building 6
Indoor Air Bibliographic Database 7
Using Animal Models to Understand
Human Susceptibility to Indoor Air 8
Reducing Indoor Air Emissions from
Aerosol Consumer Products 10
Summaries of Recent Publications 12
Summaries of "Engineering Solutions
to IAQ Problems" Symposium Papers . . 13
Glossary of Acronyms 16
Inside IAQ is distributed twice a year and
highlights indoor air quality (IAQ) research
conducted by EPA. If you would like to be added
to or removed from the mailing list, please mail,
fax of e-mail your name and address to:
Inside IAQ, Art. Kelly Leovic (MD-54)
U.S. EPA/APPCD
Research triangle Park, NC 27711
Fax: 919-541-2157
E-mail: kleovic@engineer.aeerl.epa.gov
EVALUATION OF AN IAQ SOURCE MANAGEMENT
STRA TEGY FOR A LARGE BUILDING
EPA's Air Pollution Prevention and Control Division (APPCD) developed
an approach to IAQ management in buildings that is based upon the
assumption that exposure to indoor air pollutants can be minimized given
sufficient knowledge and control of sources, sinks, and building ventilation.
This assumption implies that the source emissions and building ventilation
data are available in a form that can be used to predict exposure using
computer simulation models. Although the approach is simple in concept,
successful application may depend upon the quality and quantity of source
and ventilation data available as well as the efficacy of the models that
relate source emission and ventilation characteristics to exposure.
In apioneering effort, the State of Washington implemented a proactive IAQ
program to ensure healthful work environments in four planned new office
buildings. Key components of the program were designed to minimize
occupant exposure to indoor air pollutants in the newly constructed buildings
by ensuring adequate ventilation, utilization of low emitting products in
construction and furnishing, staged loading to minimize cross contamination
of fleecy surfaces during construction and use of a 90-day 100% outdoor air
(OA) flush-out prior to occupancy.
In 1992, APPCD conducted a pilot investigation of the source management
and control program as implemented in design and construction of one of the
buildings: the Natural Resources Building (NRB). The NRB is a six-story
mixed use office building with over 320,000 square feet (97,536 m2) of
occupiable space. Our goals were to collect a broad spectrum of data in the
NRB that would enable us to develop a focussed study to evaluate the IAQ
and cost effectiveness of the product selection, building flush-out, and
ventilation strategies used in design and construction of the next building
(Continued on Page 2)
Radon Mitigation Research Update
APPCD's annual publication, the Radon Mitigation Research Update, will
no longer be published. Updates on EPA's radon research will now be
included in Inside IAQ. If you were on the mailing list for the Radon
Mitigation Research Update and would like to receive Inside IAQ, please
send your name and address to the location listed at the left.
-------
(Continued from Page 1)
to be constructed by the State under the IAQ program. Though we
were unable to conduct the follow-on study, we did collect a great
deal of information that is instructive for design and application of
this type of proactive IAQ program.
Product source emissions characterization data that were
generated to demonstrate compliance with the State's
maximum acceptable concentrations per product were
collected from private laboratories that conducted emissions
tests and from other sources in custody of the data. The data
consisted of small- and large-chamber emissions test results,
material safety data sheets (MSDS), and/or compliance
certifications for 78 products that were proposed and/or used
in the NRB. Product categories included adhesives and
sealants, business machines, ceiling materials, floor coverings,
fireproofing, furniture, wall coverings, heating, ventilation, and
air-conditioning (HVAC) system components, paints and
coatings, and wall systems. Product loading data (number of
products or surface area per floor) were obtained for 15
products including work stations, ceiling materials, floor
coverings, seating, and tables.
Measurement of IAQ
Building air quality data were collected at sites within the
building and outdoors at completion of construction, during the
flush out, and after occupancy. The sites were selected to
investigate air quality differences between and within floors as
well as those within and outside the building. Over 200
different individual volatile organic compounds (VOCs) were
tentatively identified in the indoor air samples over the course
of the study. As is seen in Figure 1, total volatile organic
compounds (TVOCs) concentrations remained relatively
2.5
I
¥1.5
1
CD 1
o 1
c
o
O
00.5
-
1
J
-
end
flush
\
-. ,r
iJ
-
rTh^
preflush ' 30 ' 60 ' 90 ' 120 ' 266
Sampling Period (days)
D 1st floor D 4th floor D 6th floor DOutdoors
Figure 1. TVOC concentrations in the NRB
constant during the flush-out. Three compounds, tetradecane,
pentadecane, and hexadecane, dominated the indoor air VOC
concentrations at the sites where sampling stations were
located. The sum of the three compounds averaged 36 ± 4%,
77 ± 6%, and 61 ± 12% of TVOCs on the first, fourth, and
sixth floors, respectively, over the first 120 days of the study
(Figure 2). The ratio of the sum of these three compounds to
TVOCs dropped by a factor of 10 by day 266.
0.8
0.6
0.4
0.2
0
0
i
~
-
i
i— i
!
—
i
30 ' 60 ' 90
Elapsed Time (days)
—
—
120
D 1st floor D 4th floor D 6th floor
' 266
Figure 2. Ratio of the sum of the C14- C16n-alkanes
to TVOCs.
The known dominant source of these compounds, a carpet tile,
was installed on the second, third, fourth, and fifth floors. At
day 120, the characteristic carpet tile emissions constituted
80% of the TVOCs on the fourth floor where TVOC
concentrations were greater than 1.5 mg/m3. Thus, a single
source may be responsible for TVOC emissions that exceed
the State's target that no product contribute more than 0.5
mg/m3 to TVOC loading in the building 30 days after
installation. Between days 120 and 266, the ratio of the carpet
tile hydrocarbons to TVOC drops from 0.8 to below 0.05 at
the fourth floor site, indicating a significant decrease in source
strength. Small chamber emissions tests of carpet tile
submitted for compliance testing and a quality control sample
removed from the building suggest significant sample to
sample variability and demonstrate the predominance and slow
emissions decay pattern of the C14 - C16 hydrocarbons.
Attempts to predict indoor VOC concentrations from source
emissions and building ventilation data were unsuccessful.
Emissions data derived from compliance statements, MSDS
sheets, and single-point 24 hour emissions tests did not provide
sufficient data for modeling. Longer term testing (96 hour) of
carpet tile samples was indicative of the slow emissions decay
rates as well as variability among samples.
Inside IAQ, Fall/Winter 1995
Page 2
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We were unable to determine the value of the 90-day flush-out
from the data collected in the pilot study. The limited data
available suggest that the OA flush rate was 12 to 45% lower
than the target 100% OA intake rate. Given the apparently
slow emissions decay rates for the product apparently
responsible for a significant portion of the elevated building
VOC concentrations, it appears that the primary value of the
flush-out period was to shorten the period of time that
occupants were exposed to the elevated VOC concentrations
related to the source of these emissions. From the source and
building VOC data, it cannot be determined whether the
elevated concentrations in the building are due to direct
emissions from the carpet tiles or some other product that has
not been tested but was installed in the building.
Conclusions
The State's IAQ program was successful in raising the
awareness of product manufacturers to emissions from their
products. Results of the pilot study demonstrate that intra-
product sample variability and long term emissions data may
be required in order to manage indoor VOC levels by source
selection. A strategy to ensure that installed products are
representative of products tested for compliance also may be
necessary for implementation of this type of program. A
thorough evaluation of this approach to IAQ management
would require more accurate, longer term source characteriz-
ation data, more frequent building pollutant characterization,
and building ventilation system data. Finally, information
characterizing adsorption and desorption of VOCs emitted
from sources is required to evaluate the impact of sinks on
VOC contaminant levels. (EPA Contact: Mark Mason, 919-
541-4835, mmason@engineer.aeerl.epa.gov)
EPA EXAMINES INDOOR EMISSIONS FROM
CONVERSION VARNISHES
Conversion varnishes are clear varnishes commonly used as
coatings on wooden cabinets and, less frequently, on furniture.
They do not cure by drying, as do many coatings, but rather by
a chemical reaction, creating a durable water- and chemical-
resistant coating that protects the wood during its use.
Preliminary results from two studies indicate the potential of
these varnishes to emit formaldehyde and other VOCs into the
indoor environment.
The first study, being conducted by the Research Triangle
Institute under cooperative agreement with EPA, is examining
the emissions from engineered wood products into the indoor
environment and ways to prevent them. Several different
engineered wood products used to make kitchen cabinets were
tested. Preliminary results show significantly higher emissions
of both formaldehyde and volatile organics from the cabinet
components that were finished with conversion varnishes
(formaldehyde emission rates ranged from 2,000 to 5,800
ug/m2h, organics from 4,600 to 11,00 ug/m2h) than from
engineered wood components laminated with vinyl or
melamine (formaldehyde emission gates ranged from 50 to 90
ug/m2h, organics from 400 to 1,400 ug/m2h). The remainder of
this project will focus on evaluating alternatives to standard
conversion varnishes that have lower VOC emissions.
The second study, being conducted in-house at APPCD,
involves small chamber testing of conversion varnishes during
curing and aging. In a preliminary test conducted on one
commercially available varnish, the total mass of formalde-
hyde emitted was 1% of the mass of varnish applied. The
formaldehyde emission profile fit the second order decay
model:
E(t) = E0/(l+ktE0)
where:
E(t) = the emission factor as a function of time;
E0 = 29.0 ug/m2h is the initial emission factor;
k = 0.00361 m2/mg is the second-order decay rate
constant; and
t = time after the beginning of the test.
The total mass of VOCs emitted during the test period (250
hours) was 44% of the mass of varnish applied, calculated as
toluene. The predominant VOC compounds were xylene at
34% and isobutanol at 5% of the mass of varnish applied.
Additional tests will be conducted on other commercially used
varnishes and to determine the effect on emissions of multiple
coats and coating different substrates. (EPA Contact: Betsy
Howard, 919-541-7915, bhoward@engineer.aeerl.epa.gov)
Inside IAQ, Fall/Winter 1995
Page 3
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REVIEW OF CONCENTRA TION STANDARDS &
GUIDELINES FOR FUNGI IN INDOOR AIR
Exposure to fungal aerosols clearly causes human disease.
However, methods for assessing exposure remain poorly
understood, and guidelines for interpreting data are often
contradictory. APPCD, together with the Harvard School of
Public Health, is reviewing and comparing existing guidelines
for indoor airborne fungi, discussing limitations of existing
guidelines, and identifying research needs that should
contribute to the development of realistic and useful guidelines.
Existing guidelines are exclusively based on baseline data
(rather than health effects data), and are absolute (listing
numbers), relative (comparing indoors to outdoors), or a
combination of the two. Regulations controlling fungal
aerosols have been published only by the Russian Federation.
The U.S. Occupational Safety and Health Administration
(OSHA) has proposed a standard that is under review. Other
guidelines have been proposed or sponsored by North
American and European government agencies. Finally, some
of the most often quoted guidelines have been proposed by
individuals based on either prospective sampling studies or
personal experience. Guidelines range from less than 100
colony forming units (CFU)/m3 to more than 1000 CFU/m3
(total fungi) as the upper limit for non-contaminated indoor
environments.
Some major problems with existing guidelines lie in the lack
of connection to human dose/response data, reliance on short-
term grab samples analyzed only for culture, and absence of
standardized protocols for data collection, analysis, and
interpretation. Research needs include the study of human
responses to specific fungal agents, development and
widespread use of standard protocols using available sampling
methodologies, and the development of long-term, time
discriminating personal samplers that are inexpensive, easy to
use, and amenable to straightforward, relevant analysis. (EPA
Contact: John Chang, 919-541-3747, jchang@engineer.aeerl.
epa.gov)
TWO CASE STUDIES EVALUATING HVAC
SYSTEMS AS SOURCES OF BIOAEROSOLS
An overall goal of the APPCD Ventilation Research Program
is to increase our understanding of how HVAC systems can act
as sources of indoor air pollution and to develop appropriate
design, operation, and maintenance practices to reduce human
exposure. For the past 2 years, EPA, in conjunction with the
American Society of Heating, Refrigerating and
Air-Conditioning Engineers, Inc. (ASHRAE), has been
identifying and quantifying emission sources from HVAC
systems.
In the last issue of Inside IAQ (EPA/600/N-95/004,
Spring/Summer 1995, pp. 9-10, 15), a report was discussed
(EPA-600/R-95-014; NTIS PB95-178596) that showed all
currently identifiable emission sources from HVAC systems
that have been reported and published. These included
intrinsic emission sources such as fibers and products from
metal degradation; emission sources resulting from
contamination including dust, cleaning compounds, biocides,
and microbial growth; and system design/operation such as
entrainment/reentrainment, transport, and improper building
pressurization.
Microbial contamination has been an important area of this
research. Studies show that fungi, bacteria, and other micro-
organisms from indoor and outdoor sources may accumulate
inside HVAC systems. With an appropriate substrate and
sufficient moisture, these microorganisms may survive and
multiply, and bioaerosols may be distributed throughout the
building by the HVAC system. Bioaerosols are airborne
microbial contaminants, including viruses, bacteria, fungi, algae,
and protozoa plus the reproductive units, metabolites, and
particulate material associated with these microorganisms.
Two case studies were performed to evaluate whether HVAC
systems contain microbial sources that affect bioaerosol
concentrations in occupied spaces and to compare sampling
approaches that might be used in IAQ investigations.
The first was athree-story office building constructed in 1988.
It is 29,200 ft2 (2717 m2) and has atypical variable-airvolume
(VAV) medium pressure HVAC system that is well
maintained. The second, also three-story, was constructed in
1966. It is 23,700 ft2 (2200 m 2) and is served by a low
pressure perimeter induction system and interior multizone
system that is not as well maintained.
Bioaerosol emissions in the HVAC systems were examined by
making both upstream and downstream measurements at major
components, including OA intakes, air handling units (AHUs),
duct liners, mixing plenums, fans, supply and return ducts,
filter banks, diffusers, heat exchangers, condensate drains, and
perimeter induction units.
Inside IAQ, Fall/Winter 1995
Page 4
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For the first building, visual inspections showed that surfaces
of ducts and other HVAC components in contact with the air
stream were relatively clean with little dust accumulation.
There were no signs of water or microbial contamination.
Infiltration of OA occurred during HVAC system night
shutdown due to stack effect, exhaust fan operation, and
improper damper positions. These energy losses may increase
the chances of condensation that could act to deposit spores
and other bioaerosols in the ductwork.
For fungi, the concentration in bulk samples averaged 11
CFU/mg with the highest concentrations in the return air duct
linings and in the dust at filters. Concentrations at HVAC
components downstream of the filters were lower, indicating
that the filter was helpful. A total of 22 fungal taxa were
identified in the bulk samples. Cladosporiun, Penicillium,
Alternaria, and non-sporulating fungi were the most common.
Cladosporium was the dominant taxa found in HVAC system
particulate matter collected. Proportions of Aspergillus,
Penicillium, Alternaria, and non-sporulating fungi were fairly
constant throughout the HVAC system.
For bacteria, the concentrations averaged 24 CFU/mg with the
greatest concentrations (11,420 CFU/mg) found on the supply
fan housing. The next highest concentrations were found on
the central return air duct.
Airborne sampling for fungi averaged 48 CFU/m3 in the
HVAC systems, 43 CFU/m3 in the indoor air, and 17 CFU/m3
outdoors. Cladosporium was the dominant taxon in the HVAC
samples, and Penicillium and non-sporulating fungi in the
indoor air. These concentrations are generally low compared
to other studies. Airborne bacteria averaged 226 CFU/m3 in
the HVAC system, 252 CFU/m3 in the indoor air, and 87
CFU/m3 in the outdoor air. The highest concentrations (848
CFU/m3) were found in the central return at the return air fan.
This is consistent with findings at return air grilles throughout
the building. Bacteria concentrations are more uniform
throughout the building than fungi since the occupants are a
major contributor.
In the second building, HVAC system conditions did not
appear as clean as the first building. There was accumulation
of dust and debris in and around the mechanical room and on
the exterior surfaces of the HVAC systems. Ductwork had
some open drill holes where negative air pressure could draw
in air from the mechanical equipment room. There were oil
slicks on the concrete floor and condensate ran from the AHU
to a floor drain. Visual inspection of the interior system
components showed that dust accumulation was generally low;
however, a damp musty odor was evident when the AHU was
off. No moisture damage was visible.
Fungi concentrations in bulk samples averaged 5 CFU/mg.
This is much lower than comparative measurements in the first
building. The researchers suspect that concentrations were
lower due to the accumulation of inorganic debris.
Concentrations at all sites were low. Researchers identified 20
total fungal taxa with Cladosporium being dominant in HVAC
bulk samples.
Bacteria concentrations were highest in the OA duct and the
perimeter induction units. Low concentrations were found in
the supply air duct. Intermediate levels were found in the
return air duct.
Air samples showed very little contribution to bioaerosol levels
as fungi concentrations in the HVAC were generally low (58
CFU/m3). Office spaces had similar levels (44 CFU/m3).
However, when the fan section was manually disturbed, the
fungi levels were very high (greater than 8,075 CFU/m3) as
was the case with the bacteria concentrations (86,000
CFU/m3).
Conclusions
A number of comparisons can be made between the two
buildings. Typically the bulk samples yielded two to four
times as many fungi taxa as air samples, but the majority of
fungal taxa were identified using both types of sampling
techniques. However, proportions of species or taxa varied
considerably. These differences are significant and seem to
suggest that building sampling may be indicative of higher
numbers of actual taxa or species available as a source of
bioaerosols and air sampling.
Bulk sampling appears sufficient to identify microbial
reservoirs in HVAC systems, and air sampling of disturbed
reservoirs can confirm actual or potential releases. However,
due to spatial variability in settling, deposition, moisture, etc.,
multiple sites in HVAC ducts and AHUs should be sampled to
obtain representative concentrations in surface and bulk
measurements.
The quantification of bioaerosol emissions based on impaction
measurements taken upstream and downstream of HVAC
components may not be effective since short sampling periods
are not representative of the temporal variability commonly
found in emissions. Additionally, it is also difficult to capture
any existing HVAC spatial variability; component access is
typically difficult; and the need for low velocity (fan shut off)
alters the flow regime and thus the entraimment and
suspension of potential bioaerosols. Measurements taken at
terminal units, however, are easily obtained and may indicate
whether the HVAC system is discharging bioaerosols (EPA
Contact: Russell N. Kulp, 919-541-7980, rkulp@
engineer, aeerl.epa.gov)
Inside IAQ, Fall/Winter 1995
Page 5
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EFFECT OF VENTILATION ON RADON
LEVELS IN A MUNICIPAL OFFICE BUILDING
APPCD, together with the Florida Department of Community
Affairs and Southern Research Institute, is conducting research
to help assess the impact of building design, construction, and
operating features (e.g., mechanical systems) on radon and
other indoor air pollutants. The research will help APPCD
better understand the effects of various building features on
IAQ and will also provide information to support the Florida
Standard for Radon Resistant Construction in Large Footprint
Structures.
Building Description
An extensive characterization and parametric assessment study
was conducted in a typical Florida multistory commercial
building. Indoor radon levels were above the EPA guideline of
4 pCi/L and ranged from 4 to 15 pCi/L. The building has
149,000 ft2 (45,415 m 2) of floor space distributed over five
stories with an atrium that extends from the ground floor up to
a glass skylight. Each of the first fours opens out into a
balcony around the atrium. The atrium opening is enclosed
completely on the fifth floor. The building foundation is slab-
on-grade with supporting pilings under the slab and grade
beams in some locations. The slab thickness is 6 in. (15.2 cm)
with pilings that penetrate the sub-surface soil to an
undetermined depth. The building has 11 AHUs, with 2 each
on floors two through five and 3 on the first floor.
First, the HVAC system was inspected thoroughly, and a
certified test and balance contractor measured actual flow
distribution in the mechanical subsystems. Based on the
inspection of the HVAC system and continuous monitoring,
several deficiencies were noted which would be expected to
adversely affect radon levels, other IAQ factors, or energy
consumption. Specifically, OA air flow rates were far below
design values on the first and fourth floors; maximum supply
air flow rates are below design values on all but the fifth floor;
the building generally operates under negative pressure; and
there is an excessive pressure imbalance between zones,
especially on the first floor.
Measurement of IAQ Parameters
A series of measurements were made during several cycles of
building operation between May and August 1994. For
continuous measurements, IAQ data stations were used to
monitor radon, differential pressures, room temperatures,
relative humidities, and carbon dioxide (C02) concentrations
in each of 13 zones. The 13 data stations were distributed 2
per floor on the top four floors, with 5 stations distributed in
several zones on the first floor. Ten additional continuous
radon monitors were located on the first floor.
As shown in Table 1, baseline radon concentrations in the
building averaged approximately 8.1 pCi/L on the first floor
and 3.1 pCi/L on the upper floors, with a building average of
4.1 pCi/L. The data in Table 1 also show that radon
concentrations were essentially unaffected by varying the OA
damper from minimum to maximum (columns two and three).
Measurements of the building air change rate over this period
ranged from 0.15 to 0.25 hr"1, indicating that varying the OA
damper settings also has little effect on the building ventilation
rate. This suggests that ventilation in this building is primarily
by direct leakage across openings in the building shell and is
driven by local pressure differentials between specific indoor
zones and the outdoors. The observed magnitude of HVAC-
induced pressure imbalance among the first floor zones is
enough to expect that a significant portion of the observed
infiltration/exfiltration is derived from this source. Based on
these measurements, researchers concluded that too little
induced OA was coming into the building to significantly
affect ventilation in comparison to the gains and losses of air
through the building shell induced by depressurization and
pressure imbalance.
In consultation with the building owners, a temporary system
that consisted of three in-line fans was installed in the first
floor AHUs. The purpose was to determine if forced
ventilation could increase the air exchange rate and decrease
radon entry on the first floor.
As shown in the final three columns of Table 1, first floor radon
concentrations were progressively reduced with addition of
increased amounts of forced OA for ventilation. With the greatest
supply of OA (1900 cfm), the first floor radon levels dropped to
4.8 pCi/L, approximately 60% of the baseline concentration.
Radon reductions on upper floors, where additional OA was not
supplied, were not as dramatic as the first floor. Other measures
of building ventilation rate effects, such as peak excess C02, also
show a net dilution effect on both first and upper floors, indicative
of increased ventilation during the "fan on" periods. These
measurements are consistent with the fan operation adding
roughly 1200 cfm (14-22%) to the previous 5500-8500 cfm of
infiltration/exfiltration.
Conclusions from Case Study
This study demonstrates control of indoor radon levels by
introducing additional OA on the first floor only of a large,
relatively open, multistory building. The results indicate that the
greatest relative reductions in radon levels were on the first floor
where baseline radon levels were the highest. This study thus
demonstrates the potential for a targeted dilution strategy in which
OA is delivered to only one portion of a relatively open building
while interzonal floor-to-floor effects are contained or minimized.
(EPA Contact: Marc Y. Menetrez, 919-541-7081,
mmenetrez@engineer.aeerl.epa.gov)
Inside IAQ, Fall/Winter 1995
Page 6
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Table 1. Average radon levels under various operational modes (pCi L"1)
Location
1st Floor
Floors 2-5
Building
Baseline
8.1
3.1
4.1
MaxOA
7.4
3.2
4.0
MinOA
7.9
3.4
4.3
2 OA Fans
(700 cfin)
6.6
3.4
4.0
3 OA Fans
(1000 cfin)
5.6
3.1
3.6
3 OA Fans
(1900 cfin)
4.8
2.8
3.2
INDOOR AIR BIBLIOGRAPHIC DATA BASE
The National Center for Environmental Assessment (NCEA)
published a revised version of the Indoor Air - Bibliographic
Data Base in 1994. The bibliographic data base is an
extensive bibliography of reference materials on IAQ. The
data base is organized by key word, lead author, and citations.
A more current copy of the bibliographic data base
is available on computer diskette through EPA. The hard copy
version of the data base is available through the NRMRL's
Technology Transfer and support Division (513-569-7562)
and the National Technical Information Service (NTIS) (703-
487-4650). (EPA Contact: Beverly Comfort, 919-541-4165,
comfort.beverly@epamail.epa.gov)
Organizational Changes
OFFICE OF RESEARCH AND DEVELOPMENT (ORD)
CURRENT ORGANIZATIONAL TITLES
National Risk Management Research Laboratory/ Air pollution Prevention and
Control Division/ Indoor Environment Management Branch (Mike Osborne,
919-541-4113)
National Exposure Research Laboratory/ Human Exposure Research Division
(Gerald Stelma, 513-569-7384)
National Health and Environmental Effects Research Laboratory
(Sue McMaster, 919-541-3844)
National Exposure Research Laboratory/ Human Exposure and Field Research
Division (Miriam Rodon-Naveira, 919-541-3075)
National Center for Environmental Assessment
(Beverly Comfort, 919-541-4165)
National Risk Management Research Laboratory/ Technical Transfer and
Support Division (513-569-7562)
Formerly
Air and Energy Engineering Research
Laboratory/Radon Mitigation Branch
and Indoor Air Branch
Environmental Monitoring and
Sampling Laboratory
Health Effects Research Laboratory
Atmospheric Research and Exposure
Assessment Laboratory
Environmental Criteria and
Assessment Office
Center for Environmental Research
Information
Inside IAQ, Fall/Winter 1995
Page 7
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USING ANIMAL MODELS TO UNDERSTAND
HUMAN SUSCEPTIBILITY TO INDOOR AIR
Often, the signs and symptoms of exposure to indoor air
contaminants appear in only a few of the many exposed
individuals, even though exposure levels appear to be similar.
This suggests that differences in individual susceptibility play
an important role in determining responses to exposure.
Historically, the development of animal models has greatly
facilitated the study of a variety of biological and toxicological
problems. Many of the common signs and symptoms of indoor
air exposure apparently involve direct effects on the nervous
system or are mediated directly or indirectly by the nervous
system. These considerations prompted EPA' s National Health
and Environmental Effects Research Laboratory (NHEERL)
to hold a workshop on animal models of nervous system
susceptibility to indoor air contaminants. The workshop was
held in October 1994 in Chapel Hill, North Carolina, and
included a number of national and international scientific
experts.
The purpose of the workshop was to provide scientific input
into EPA's research planning process with regard to the
development of animal models to determine susceptibility to
indoor air pollutants. The workshop included: 1) human
clinical and epidemiological evidence regarding exposures and
outcomes; 2) possible experimental designs and modeling; 3)
determining differences in susceptibility; and 4) proposed
experiments and modeling for testing hypotheses.
Clinical and Epidemiological Evidence
The human clinical conditions discussed were multiple
chemical sensitivity (MCS), sick building syndrome (SBS),
and building-related illness (BRI). BRI is the best defined and
involves building contaminants of known identity which
produce definitive health outcomes. One example of BRI is
legionnaires' disease. SBS, less well defined, involves exper-
ienced illness which is alleviated upon leaving the building.
Often the causes of SBS are unknown. The health problems
reported in SBS vary, but often include a number of
subjectively experienced symptoms. MCS is least well
specified. In MCS, a diffuse array of symptoms are reportedly
triggered by exposure to a variety of different chemicals, and
are not necessarily restricted to any particular location or class
of compounds. As with SBS, the health outcomes in MCS are
based on reports of subjective discomfort or illness for which
there are few or no corresponding clinical signs of illness or
dysfunction. There is no consensus in the medical community
about the existence of MCS, and the lack of objective evidence
of impairment represents a major impediment in the
development of animal models of such conditions in a
traditional sense.
One conclusion from the workshop was that better character-
izations of the human conditions are needed. However, many
workshop participants stated that the enigmatic nature of the
human clinical conditions did not preclude the development of
animal models, because valid test methods and corresponding
animal models currently exist for many relevant outcomes.
These methods and models could be used to test a variety of
hypotheses, regarding susceptibility to indoor air contaminants.
Possible Experimental Designs and Models
Traditional experimental approaches tend to emphasize
measures of central tendency, and minimize the influence of
individual subjects deviating far from population norms. One
approach proposed to identify susceptible individuals was to
examine those subjects already at the extremes of the normal
distribution of test scores, and to determine whether they might
be most susceptible to exposure.
Another experimental approach addressed the goal of
identifying genetic contributions to susceptibility. This
approach involved the study of genetically defined inbred
strains of laboratory animals, which could be ranked for
sensitivity to exposure. This would provide arepeatable supply
of individuals with a predetermined susceptibility, thus
facilitating the identification of genetic factors that influence
susceptibility.
Quantitatively, it was suggested that variability in response
outcome be considered as the focus of, rather than a detractor
from, the research effort. Sources of individual variability
include differences in uptake of chemicals, pharmacokinetic
distribution to target sites, and response to the agents.
Variability can be both a within-subject, as well as a between-
subjects, consideration because the susceptibility of an
individual may vary substantially over time. It is important to
establish dose-response relationships for definitive outcomes
in order to establish legitimate cause-and-effect relationships.
Determining Differences in Susceptibility
Several hypotheses were discussed concerning how
susceptibility to exposure may be acquired or altered in
otherwise normal individuals. One potential mechanism
involves classical conditioning, in which the temporal pairing
of a previously neutral stimulus (conditioned stimulus) with a
biologically active stimulus (unconditioned stimulus) results in
a learned association. The previously neutral stimulus alone
then elicits the biological response. Once the association is
established, a biological response could be triggered by
exposure to levels of stimuli which previously had no effect.
The responses to classically conditioned stimuli, however,
typically diminish rather quickly without continued pairingsof
the conditioned and unconditioned stimuli, which is not
Inside IAQ, Fall/Winter 1995
Page .
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obviously present in MCS. Another type of learning, operant
conditioning, involves the elicitation of responses which are
followed by either positive or negative consequences.
Responses that are "reinforced" in this fashion may be much
longer lived. A number of experiments have shown that
susceptibility to chemical treatment can be altered
substantially by operant conditioning.
Stress may also influence the susceptibility to a chemical
treatment through the consequences of activation of a complex
neuroendocrine system. Personal and social factors may alter
the response to stress, and the resultant health consequences
can involve multiple bodily sites and disorders.
Neural plasticity, defined as modifications in the functional
properties of a neurological system as a result of experience,
may also serve as a source of increased sensitivity to chemical
exposure.
Finally, a phenomenon know as time-dependent sensitization,
which involves progressive and enduring enhancement of
behavioral and biochemical responsiveness to chemical
treatment, could also underlie augmented susceptibility.
Testing of Hypotheses
Many symptoms reported following exposure to indoor air
contaminants involve sensory complaints (odor or irritation),
cognitive or behavioral changes including frank avoidance of
odors or environments, and inflammation. Specific
experimental models of these topics were discussed. The
function of the trigeminal and olfactory systems could be
investigated both electrophysiologically and behaviorally. The
measurement of respiratory depression following exposure can
be used to test hypotheses regarding the irritancy of inhaled
substances.
The perception of odor varies greatly among individuals, and
can be influenced by psychological factors such as expectancy
and learning. The concentrations which animals will terminate
exposure vary both between and within animals as a function
of exposure history. Neuro-immune interactions are also
important to consider, and might be profitably studied using
immuno-deficient mice or other well-characterized models.
It was demonstrated that several hypotheses of the
development of susceptibility could be profitably examined
experimentally using existing animal models. One important
point was that animal models need not replicate every aspect
of the human condition, but are of value if they focus on a
single facet for study. The importance of selecting species-
appropriate endpoints in animal models was emphasized.
Animal models that specifically address issues related to IAQ
include the sensory aspect of odor and irritation perception,
behavioral avoidance of contaminated atmospheres, and
neurogenic inflammation. A research program based on animal
models would augment and complement continued efforts to
better characterize the human conditions. These research
efforts would likely improve the ability to assess the risks of
exposure of susceptible individuals to indoor air environments,
as well as in other exposure situations of concern to EPA.
Source: EPA Report, MS-95-264-USEPA, 1995. (EPA
Contact, Ken Hudnell, 919-541-7866,
hudnell@am.herl.epa.gov)
Inside IAQ, Fall/Winter 1995
Page 9
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REDUCING INDOOR AIR EMISSIONS FROM
AEROSOL CONSUMER PRODUCTS
Because aerosol consumer products, such as those used for
personal care, pest control, and cleaning, are commonly used
in the indoor environment, APPCD is supporting research to 1)
better understand personal exposures to aerosol consumer
products, and 2) to develop pollution prevention techniques to
reduce exposures. A group of Industry Partners is actively
involved in the research to ensure that the results will be
practical for industry.
Developing Measurement Methods and Models
Georgia Tech and the University of Illinois are working
together to develop measurement methods and models for
manufacturers to use to develop a better understanding of
aerosol behavior. This improved understanding can then be
used by manufacturers to develop and produce more
efficacious and less toxic aerosol consumer products.
Georgia Tech is developing a Mass Spectrometer (MS)/MS
system for the chemical characterization of representative
aerosol products. They are also measuring particle sizes for
various spray patterns using a Malvern Analyzer and are
developing an electron mobility analyzer for future work on
particle sizing in conjunction with the MS system. The MS/MS
system eliminates the need for collection and concentration
techniques and chromatographic separations, and is
particularly sensitive to polar compounds. As a result, the
system is well suited for real-time, direct analysis of aerosol
consumer products. The University of Illinois is developing
techniques and instrumentation capabilities to measure aerosol
transport and distribution in rooms. A model is also being
developed to predict aerosol behavior in rooms. Researchers at
the University of Illinois are currently analyzing the spray
patters of representative aerosol products using particle image
velocimetry (PIV) techniques. Figure 3 illustrates PIV data
showing aerosol particle concentrations at various distances
from the spray nozzle.
The ultimate outputs from this project include: 1) indoor air
characterization data on emissions from representative aerosol
consumer products as a function of time; 2) methods,
technology, and models to measure and predict emissions and
personal exposures from use of aerosol products indoors; and
3) pollution prevention techniques and guidelines for the
manufacture and use of these products.
Innovative Spray Nozzle Design
In another project, Purdue University has developed and
demonstrated an innovative spray nozzle design for use with
precharged aerosol containers. This design is similar to one
previously developed and demonstrated at Purdue for pump-
and trigger-dispensed aerosol products.
The new dispenser design (Figure 4) allows manufacturers to
reformulate selected aerosol consumer products (e.g., personal
care, hair care, degreasers, and hard surface cleaners) using
water and air in place of VOC solvents and hydrocarbon
propellants in precharged systems, while still maintaining
acceptable product delivery characteristics.
Laser diffraction measurements made at Purdue indicate that
the new dispenser design produces product droplets in the
desired size range. Data demonstrate that Sauter Mean
Diameters (SMDs) are within experimental error of 70 /^m for
air to liquid ratios (ALRs) as low as 70%. Reducing the ALR
below 0.75% results in a rapid increase in the mean drop size.
The data also indicate little sensitivity of mean drop size to
viscosity over the range considered in this study (0.020 to
0.080 kg/m-s, or 20 to 80 cP).
Data also show that air consumption is below target values and
supply pressures are acceptable. Dispenser performance is
relatively insensitive to product formulation, as described by
its viscosity and surface tension. This simplifies manufacturing
since a single dispenser design can then be used with a wide
array of products.
Current research at Purdue is addressing three questions
necessary to provide rational design guidelines to industry.
First, when the product exits the dispenser, how does it break
up into ligaments and drops? Second, to what extent does the
spray entrain surrounding air? Third, what challenges must be
met during intermittent nozzle operation? Pulsed holography
and PIV are being used to acquire the necessary data to answer
these questions. (EPA Contact: Kelly Leovic, 919-541-7717.)
Inside IAQ, Fall/Winter 1995
Page 10
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Ajr aerosol 2 (averaged over 120 replications)
10 12
Figure 3. Time averaged concentration contour plots of
aerosol particles (1 in. = 2.54 cm).
Brass Top
Plate -
Liquid —
Acrylic
Containment
Tube •
Acrylic
Exit ~^^
Orifice
f
1
_Z '
*
ilr
- ' H.
--
*
— Liquid
_ Brass
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Tube
Air
— Injection
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\
Porous Insert
Figure 4. Prototype of new dispenser developed by
Purdue University
THE INDOOR AIR QUALITY
INFORMATION CLEARING HOUSE
(IAQ INFO)
IAQ INFO is an easily accessible, central source of
information on indoor air quality. It is supported by EPA's
Office of Air and Radiation's Indoor Environment Division.
IAQ INFO can provide information on many aspects of indoor
air quality:
+ Indoor air pollutants and their sources
+ Health effects of indoor air pollution
+ Testing and measuring indoor air pollutants
+ Constructing and maintaining homes and buildings to
minimize IAQ problems
+ Existing standards and guidelines related to IAQ
+ General information on Federal and State Legislation
IAQ INFO contains:
+ Citations and abstracts on more than 2,000 books, reports,
newsletters, and journal articles
+ An inventory of publications prepared by the Federal
government, including fact sheets, pamphlets, directories,
training materials, and reports
+ Information on more than 150 government research,
public interest, and privte sector organizations in the IAQ
field
You may call a toll-free number to speak to an information
specialist, Monday through Friday, 9:00 a.m. to 5:00 p.m.
EST. After hours, you may leave a voice message, or you may
inquire by fax or mail anytime.
IAQ INFO
P.O. Box 37133
Washington, DC 20013-7133
1-800-438-4318
202-484-1307
Fax:202-484-1510
Inside IAQ, Fall/Winter 1995
Page 11
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SUMMARIES OF RECENT PUBLICA TIONS
This section provides summaries of recent
publications on EPA's indoor air
research. The source of the publication is
listed after each summary. Publications
with NTIS numbers are available
(prepaid) from the National Technical
Information Service at: 5285 Port Royal
Road, Springfield, VA 22161, 703-487-
4650 or 800-553-6847. EPA papers
presented at the Engineering Solutions to
Indoor Air Quality Problems symposium
held in July 1995 are summarized
beginning on page 13.
Laboratory Assessment ofth e Permeability
and Diffusion Characteristics of Florida
Concretes: Phase II. Field Samples and
Analyses-The report summarizes a study
that establishes the capability to measure
concrete's permeability and diffusivity and
to correlate the physical parameters of the
concrete to the measured diffusion and
permeability coefficients. For both
permeability and diffusivity, the amount of
water added to the mix at the site was
directly and positively related and identified
as a possible major factor. The total amount
of sand and stone in the mix was possibly
correlated to the permeability. A third
possible correlation involved the amount of
fly ash or the cement to fly ash ratio.
Source: EPA Report, EPA/600/R-95/103
(NTIS PB95-243168), July 1995. (Lead
Author: R Snoddy; EPA Contact: David
C. Sanchez, 919-541-2979, dsanchez@
engineer, aeerl.epa.gov)
Statewide Mapping of Florida Soil Radon
Potentials, Vol. 1, Technical Report, VoL 2,
Appendices A-P-The report gives results of
statewide mapping of Florida soil radon
potentials. The maps provide scientific
estimates of regional radon potentials that
can serve as a basis for implementing
radon-protective residential building
standards. Source: EPA Report, EPA-600-
R-95-142a& 142b (NTIS PB96-104351 &
-104369), September 1995. Lead Author:
Kirk K. Nielson; EPA Contact: David C.
Sanchez, 919-541-2979, dsanchez@
engineer, aeerl.epa.gov)
Ozone Generators in Indoor Air
Settings-This report addresses typical
questions posed by both consumers and
professionals about the effects of ozone as
an IAQ ameliorative. Source: EPA Report,
EPA-600/R-95-154. (NTIS PB 96-
100201), October 1995, (Lead Author and
EPA Contact: Ray Steiber, 919-541-2288,
rsteiber@engineer.aeerl.epa.gov)
Lumped-parameter Model Analyses of
Data from the 1992 New House Evalua-
tion Project—Florida Radon Research
Program-The report documents analyses of
Phase 2 data from the Florida Radon
Research Program's (FRRP's)New House
Evaluation Project that were performed
using a lumped-parameter model. The
analyses focused primarily on empirically
characterizing the radon resistance of the
house/soil interface for different foundation
designs. The analyses were also aimed at
comparing the effectiveness of active and
passive radon protection features. Source:
EPA Report, EPA/600/ R-95/090 (NTIS
PB95- 243077), July 1995. (Lead Author:
Kirk K. Nielson; EPA Contact: David C.
Sanchez, 919-541-2979,
dsanchez@engineer.aeerl.epa.gov)
Design and Testing of Sub-slab Depres-
surization for Radon Mitigation in North
Florida Houses, Part I-Performance and
Durability; Vol. 1, Technical Report; Vol.
2, Data Appendices-The objectives of this
study were to develop and test the use of a
soil depressurization computer model as a
design tool, to optimize the sub-slab soil
depressurization design for North Florida
houses, and to observe system performance
and durability. Radon concentrations,
originally on the order of 10-30 pCi I"1 were
reduced to below 4 pCi L -1 in all nine
houses studied. The systems retained
effectiveness during the 3-18 month
durability observations. Source: EPA
Report, EPA-600/R-95-149a& 149b(NTIS
PB96-103585 & -103593), September
1995. (Lead Author: C. E. Roessler; EPA
Contact: David C. Sanchez, 919-541-2979,
dsanchez@ engineer.aeerl.epa.gov)
Relative Sensitivity of the Ocular
Trigeminal, Nasal Trigeminal and
Olfactory Systems to Airborne Chemi-
cals-Thresholds for eye irritation and odor
resulting from exposure to ketones and
alkylbenzenes are discussed. Eye irritation
thresholds are well above odor thresholds,
and both sensory thresholds declined with
carbon chain length. Also, eye irritation
thresholds were remarkably close to nasal
pungency thresholds obtained previously in
persons lacking olfaction (i.e., anosmics)
Source: Chemical Senses, Vol. 20, No. 2,
pp. 191-198, 1995. (Lead Author: J.
Enrique Cometto-Muniz; EPA Contact:
Ken Hudnell, 919-541-7866, hudnell@
am.herl.epa.gov)
Evaluation of Building Design,
Construction, and Performance for the
Control of Radon in Florida Houses:
Evaluation of Radon Resistant Construc-
tion Techniques in Eight Houses-The eight
houses in this study were built following
Florida's radon resistant construction
standard. The study shows that operation of
well designed and constructed HVAC
systems does not significantly affect indoor
radon, regardless of the pressures induced
between interior air zones. Source: EPA
Report, EPA-600/R-95-114 (NTIS PB95-
253910), July 1995. (Lead Author: D. E.
Hintenlang, Univ. of Florida; EPA Contact:
David C. Sanchez, 919-541-2979,
dsanchez@engineer.aeerl.epa.gov)
Soil and Fill Laboratory Support-1992,
Radiological Analyses, Florida Radon
Research Program-Analyses performed
on soil and fill samples included moisture,
radium-226, and radon emanation
coefficient determinations for 164
samples representing 21 sites. Central
Florida (Polk County) sites were charac-
terized by elevated radioactivity fill over
a wide rand of substrate concentrations.
Source: EPA Report, EPA-600-R-95-
145, September 1995. (Lead Author: C.E.
Roessler; EPA Contact: David C.
Sanchez, 919-541-2979, dsanchez@
engineer, aeerl.epa.gov)
Inside IAQ, Fall/Winter 1995
Page 12
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ENGINEERING SOLUTIONS TO INDOOR AIR QUALITY PROBLEMS SYMPOSIUM
An international symposium, Engineering Solutions to Indoor Air Quality Problems, was held July 24-26, 1995, in Research
Triangle Park, North Carolina. The symposium was cosponsored by APPCD and the Air & Waste Management Association
(A&WMA). Topics included: source characterization, source management and pollution prevention, ventilation and modeling, air
cleaning, and biocontaminant control. There were over 200 attendees from around the world, including researchers from the
government, private sector, industry, and academia. Summaries of APPCD-sponsored papers presented at the Symposium are below.
Proceedings from the symposium will be published by the A&WMA and EPA in late 1995. To obtain a copy of the proceedings,
contact the A&WMA at 412-232-3444 or NTIS at 703-487-4650. The next symposium will be held in 1997 in Research Triangle
Park. An announcement and call for papers will be sent to everyone on the Inside IAQ mailing list.
Aerosol Filtration Efficiency ofln-Duct
Air Cleaners-A test method has been
developed for measuring the fractional
aerosol filtration efficiency of air
cleaners. The method provides a reliable
and accurate means of measuring air
cleaner fractional efficiencies over the
particle diameter size range of 0.01 to 10
/^m. The fractional efficiency of several
common air cleaners was evaluated:
fiberglass furnace filters, paper-media
filters, and several types of electronic air
cleaners. Results show that filtration
efficiency is highly particle size
dependent over the 0.01-10 ^m size
range. Filtration efficiency was also seen
to be dependent upon flow rate and the
dust load condition of the air cleaner.
(Lead Author: James T. Hanley; EPA
Contact: Leslie E. Sparks, 919-541-245 8,
lsparks@engineer.aeerl.epa.gov)
Air Exchange Measurements in an IAQ
Test House-Air exchange rates in an
IAQ test house have been determined by
using tracer gas techniques. It was found
that, with all windows and outside doors
closed, the variation of air exchange rate
covered a six-fold range: from as low as
0.18 per hour to as high as 1.1 per hour.
The major factors that affect air exchange
include: weather conditions, operation of
the heating and air conditioning system,
closing or opening interior doors, and
changes in house structure. (Lead Author:
Zhishi Guo; EPA Contact: Leslie Sparks,
919-541-2458,
lsparks@engineer.aeerl.epa.gov)
Characterization of Aerosol Consumer
Products-This paper discusses the devel-
opment of a mass spectrometer (MS)
interface that will allow for the real-time
characterization of both the particulate
and gaseous phases of an aerosol
consumer product. An electron mobility
analyzer is being designed to define to
particle size of the aerosol droplets. This
is being interfaced with an atmospheric
triple quadrupole MS for the gaseous
characterization. Preliminary data on
particle size of the aerosol products and
on gaseous characterization are included.
See article on page 10. (Lead Author:
Charlene W. Bayer; EPA Contact: Kelly
Leovic, 919-541-7717, kleovic@
engineer, aeerl.epa.gov)
Characterization of the Usefulness of
the Field and Laboratory Emission Cell
(FLEC) for the Evaluation of
Emissions from Engineered Wood
Products-A series of tests was designed
to evaluate the performance of the FLEC
as applied to the testing of emissions from
engineered wood products. The objective
was to determine appropriate parameters
for testing the emissions of formaldehyde
and other possible aldehydes, ketones,
and VOCs. Commercially available
household products (e.g., kitchen
cabinets) constructed from different types
of engineered wood with various
laminates and coatings were tested. (Lead
Author: Nancy F. Roach; EPA Contact:
Elizabeth M. Howard, 919-541-7915,
bhoward@engineer,aeerl.epa.gov)
A Comparison of Design Specifications
for Three Large Environmental
Chambers-Large (room-sized) environ-
mental test chambers are currently being
constructed by three government organiz-
ations (U.S. EPA, National Research
Council Canada, and Australia's Institute of
Minerals, Energy, and Construction) to
characterize sources of indoor air pollution.
The chambers, while intended for similar
purposes, have been designed and
constructed to different specifications. A
study will compare the design and
performance of these chambers in order to
develop a better understanding of how they
can be best used for IAQ measurements.
(Lead Author & EPA Contact: Betsy M.
Howard, 919-541-7915,
bhoward@engineer.aeerl.epa.gov)
Developing Guidance for Considering
Cost-Effectiveness when Selecting and
Designing IAQ Control Approaches-
APPCD is undertaking a program to
develop a practical methodology that will
facilitate cost-effectiveness considerations
in selecting among alternative IAQ control
options. This paper describes an initial
effort where the methodology will be tested
by using it to conduct a sensitivity analysis
for a 4-story office building. The cost-
effectiveness of ventilation, air cleaning,
and source management will be compared
as key variables associated with the
building, the HVAC system, and the IAQ
control system are systematically varied.
Lead Author & EPA Contact: D.B.
Henschel, 919-541-4112, bhenschel@
engineer, aeerl.epa.gov)
Inside IAQ, Fall/Winter 1995
Page 13
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The Effect of Relative Humidity on
Gaseous Air Cleaner Media Perform-
ance: Toluene Adsorption by Activated
Carbon-Performance characteristics of
activated carbon as a gas-phase air
cleaner media were examined. Toluene
breakthrough curves at relative humidities
(RHs) from below 5 to 80% were
obtained. RH appears to have negligible
influence on the adsorption of toluene
below 50%. By 75% RH, the adsorption
of the toluene is decreased. The linearity
of the log-log relationship between the
concentration and the 10% breakthrough
time for lower concentration challenges
indicates that high concentration
breakthrough data can be used to predict
breakthrough time for lower
concentration challenges. (Lead Author:
M. K. Owen; EPA Contact: Leslie
Sparks, 919-541-2458, lsparks@
engineer, aeerl.epa.gov)
Effects of Altered Ventilation on Radon
and IAQ Variables in a Five-Story
Municipal Office Building-This paper
summarizes a study of a multistory office
building where radon and other air
quality parameters were monitored as the
HVAC systems were modified. See
article on page 6. (Lead Author: Ashley
D. Williamson; EPA Contact: Marc Y.
Memetrez, 919-541-7981, mmenetrez@
engineer, aeerl. epa. gov)
Effervescent Atomization at Low Air/
Liquid Ratios-A new type of consumer
product aerosol dispenser that uses water
instead of VOC solvents and air in place
of hydocarbon propellants is described.
The primary feature of this dispenser is
the elimination of VOC carrier liquids
and hydrocarbon propellants from a
variety of consumer products. The aerosol
dispenser is insensitive to product fluid
physical properties (surface tension and
viscosity) which in turn allows a single
design to be employed for a wide variety
of products. See article on page 10. (Lead
Author: J. Sutherland; EPA Contact:
Kelly Leovic, 919-541-7717,
kleovic@engineer. aeerl. epa.gov)
Energy Impacts of Compliance with
ASHRAE Standard 62-1989 in a Hot &
Humid Climate-The main objectives of
this study were to ascertain the energy
impacts associated with increasing OA
for compliance with ASHRAE Standard
62-1989 and to investigate the relative
energy efficiencies of the building
systems and operations and maintenance
procedures. Manual computations and
computer simulations were made to
calculate energy consumption. (Lead
Author: Pete Rojeski; EPA Contact: Russ
N. Kulp, 919-541-7980, rkulp@
engineer, aeerl.epa.gov)
Evaluation of an Indoor Air Quality
Source Management Strategy for Large
Building Construction^ conjunction
with the State of Washington, a pilot
study was conducted to evaluate the air
quality, building performance, and
loading data that influence the ability to
predict IAQ from product emissions
testing and building operation data. See
article on page 1. (Lead Author & EPA
Contact: Mark Mason, 919-541-4853,
mmason@ engineer.aeerl.epa.gov)
Increases in Levels of Breathable Fine
Particles Due to the Application of
Carpet Fresheners in a Suburban
Home-The paper details the results of a
study in which two carpet fresheners were
applied to the carpet of a suburban home.
The data show that there is a measurable
increase in breathable fines after each
application, but that the increase is
transitory, lasting no more than 8 to 24
hours. (Lead Author & EPA Contact:
Raymond W. Steiber, 919-541-2288,
rsteiber@engineer. aeerl.epa.gov)
Measurement of Indoor Air Emissions
from Office Equipment-EPA, Research
Triangle Institute, and a group of office
equipment manufacturers have developed a
test method for measuring indoor air
emissions from office equipment. The
method is intended to characterize emis-
sions from office equipment and to support
identification of potential pollution
prevention strategies. The paper describes
the test method including: chamber
construction, clean air supply, operational
and control systems, sample collection and
analysis equipment, standards generation
and calibration systems, and performance
characteristics. Preliminary test results from
two dry-process photocopy machines are
also included. (Lead Author & EPA
Contact: Kelly W. Leovic, 919-541-7717,
kleovic@ engineer.aeerl.epa.gov)
Microbiological Screening of the Indoor
Air Quality in a Large Building-A
microbiological screening study of a non-
compliant five-story office building in
Florida was conducted to generate baseline
measurements that could be used to study
the impact of ventilation systems design and
operation on microbiological
contamination. This paper presents the
results from that microbiological screening
study. See article on page 4. (Lead Author:
D. W. Van Osdell; EPA Contact: Russ N.
Kulp, 919-541-7980, rkulp@engineer.
aeerl.epa.gov)
A Novel, Full-Scale, Whole-Field,
Optical Diagnostic Technique for
Improvement of Indoor Air Quality-A
novel, full-scale, whole-field, optical
diagnostic technique and instrumentation
have been developed to study aerosol
transport in the indoor environment. The
purpose is to better understand aerosol
consumer products and to develop pollution
prevention strategies to reduce exposure.
Both instantaneous structures and statistical
properties of air flow have been calculated
to determine quantitatively the
characteristics of indoor air flow. See
article on page 10. (Lead Author: Michael
M. Cui; EPA Contact: Kelly W. Leovic,
191-541 -7717, kleovic@engieering.
aeerl.epa.gov)
Inside IAQ, Fall/Winter 1995
Page 14
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Ongoing Evaluation of Sources and
Factors affecting Emissions from
Engineered Wood Products-This project
is characterizing indoor air emissions
from engineered wood products and
identifying and evaluating pollution
prevention approaches for reducing
indoor air emissions from these products.
The research is being conducted in five
phases: (1) evaluate existing data and
testing methodologies; (2) convene a
research planning meeting; (3) select
high-priority emissions sources; (4)
evaluate high-priority emission sources;
and (5) develop and demonstrate pollution
prevention approaches for reducing
indoor air emissions from selected high-
priority sources. This paper presents the
results of Phases 1 through 3. (Lead
Author: Sonji L. Turner; EPA Contact:
Betsy Howard, 919-541-7915,
bhoward@engineer. aeerl.
epa.gov)
VOC Removal at Low Contaminant
Concentrations Using Granular
Activated Carbon-Beds of granular
activated carbon are the most commonly
used air cleaning technology for VOCs.
However, design and operating data at the
low concentrations encountered indoors
are scarce, and extrapolation to those
concentrations has not been
demonstrated. Small-scale carbon beds
have been challenged with single
contaminants at concentrations ranging
from 4 0 4000 mg/m3. Results suggest
that higher concentration, single
component breakthrough tests, which are
short and easily obtained, may be
extrapolated to low concentrations. (Lead
Author: D. W. VanOsdell; EPA Contact:
Leslie E. Sparks, 919-541-2458,
lsparks@engineer. aeerl.epa.gov)
A Study of the Structures of Spray
Cones Utilizing Digital Particle Image
Velocimetry-This paper discusses the
dynamic physical properties of a spray
cone using PIV techniques. The dynamic
structures of aerosol size, concentration,
and velocity are included. The results can
be used to improve the efficiency of
aerosol products, to understand the
characteristics of the transport
mechanism, and to develop pollution
prevention strategies. See article on page
10. (Lead Author: Michael M. Cui; EPA
Contact: Kelly W. Leovic, 919-541-
7717, kleovic@engineerl. aeerl. epa.gov)
Susceptibility of Fiberglass Duct Lining
to Fungal (Penicillium Chrysogenum)
Growth-^ series of experiments, each
lasting 6 weeks, was conducted in static
environmental chambers to evaluate the
conditions that support the growth of a
fungus, penicillium chrysogenum, on
fiberglass duct lining. Two different
fiberglass duct liners and one fiberboard
duct, all newly purchased, were evaluated
following inoculation with P.
chrysogenum. The studies demonstrated
that the xerophilic mold, P. chrysogenum,
amplified under conditions of high RH
even on newly purchased duct lining, and
that either wetting or dirtying increased
material susceptibility. To prevent the
growth of P. chrysogenum, dust
accumulation and/or RH needs to be
properly controlled in the HVAC duct.
(Lead Author: K. K. Foard; EPA Contact:
John C. W. Chang, 919-541-3747,
jchang@engineer.aeerl.epa.gov)
Sampling and Analysis of VOCs for
Indoor Air Source Characterization-
This paper discusses a number of issues
related to sampling and analysis of VOCs
that need to be addressed in the design
and performance of source character-
ization testing for small chambers, large
chambers, test houses, and in the field.
(Lead Author: Roy Fortmann; EPA
Contact: Mark Mason, 919-541-4835,
mmason@engineer. aeerl.epa.gov)
Short and Long Term VOC Emissions
from Latex Paint-Latex paint (interior,
water-based) is being evaluated in order
to develop methods for predicting
emissions of VOCs over time. Painted
gypsum board is placed in dynamic flow-
through test chambers. Results show that
most of the Texanol® emissions occur
within the first few days, and emissions of
ethylene glycol occur over several
months. This behavior indicates that
evaporative mass transfer processes
dominate the short term emissions, while
long term emissions are limited by
diffusion processes within the gypsum
board. (Lead Author: Kenneth Krebs;
EPA Contact: Bruce A. Tichenor, 919-
541 -2991, btichenor@engineer.aeerl.epa.
gov)
Review of Concentration Standards,
Guidelines, and Proposals for Indoor
Fungi-This paper provides a complete
review of current standards, guidelines,
and proposals for levels of indoor fungi.
See article on page 4. (Lead Author:
Carol Y. Rao; EPA Contact: John C. W.
Chang, 919-541-3747, jchang@
engineer, aeerl. epa.gov)
Inside IAQ, Fall/Winter 1995
Page 15
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Glossary of Acronyms
AHU-Air Handling Unit
ALR-Air to Liquid Ratio
APPCD-Air Pollution Prevention and Control Division
ASHRAE-American Society of Heating, Refrigerating
and Air-Conditioning Engineers, Inc.
A&WMA-Air and Waste Management Association
BRI-Building-related Illness
CPU-Colony Forming Units
EPA-U.S. Environmental Protection Agency
FLEC-Field and Laboratory Emissions Cell
FRRP-Florida Radon Research Program
HVAC-Heating, Ventilating, and Air-Conditioning
lAQ-Indoor Air Quality
MCS-Multiple Chemical Sensitivity
MS-Mass Spectrometer
MSDS-Material Safety Data Sheets
NHEERL-National Health and Environmental Effects
Research Laboratory
NRB-Natural Resources Building
NRMRL-National Risk Management Research Laboratory
NTIS-National Technical Information Service
OA-Outdoor Air
ORD-Office of Research and Development
OSHA-Occupational Safety and Health Administration
PlV-Particle Image Velocimetry
RH-Relative Humidity
SBS-Sick Building Syndrome
SMD-Saunter Mean Diameter
TVOC-Total Volatile Organic Compound
VAV-Variable Air Volume
VOC-Volatile Organic Compound
United States
Environmental Protection Agency
Air Pollution Prevention and Control Division
MD-54
Research Triangle Park, NC 27711
Official Business
Penalty for Private Use
$300
EPA/600/N-95/007, Fall/Winter 1995
An Equal Opportunity Employer
FIRST CLASS MAIL
POSTAGE AND FEES PAID
EPA
PERMIT No. G-35
Inside IAQ, Fall/Winter 1995
Page 16
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