United states
Environmental Protection
Agency
Research and Development
Office of Acid Deposition, Environmental
Monitoring and Quality Assurance.
Washington DC 20460
EPA/600/S6-88/009a Sept. 1988
SEPA Project Summary
Incloqr Air Quality in Public
Buildings: Vblume I
L S. Sheldon, R W. Handy, T. D. Hartwell, R. W. Whitmore, H. S. Zelon, and
E. D. Rellizzari
This report documents the first of two
studies of indoor air quality in public
buildings carried out by the U.S. En-
vironmental Protection Agency in re-
sponse to public and Congressional con-
cern. A total of 10 buildings were studied
in the program. A report on the last six
buildings studied (Sheldon 1988) is be-
ing published simultaneously with this
report, which deals with the first four
buildings investigated.
This Project Summary was developed by
ERAS Office of Acid Deposition, En-
vironmental Monitoring and Quality
Assurance, Washington, DC, to announce
key findings of the research project that
is fully documented in a separata report
of the same title. (See Project Report
ordering information at back),
Introduction
In 1982. Congress mandated that the US.
Environmental Protection Agency (EPA) carry
out a study of indoor air quality. Because very
little was known at that time about volatile
organic chemicals (VOCs) in indoor air, it was
.decided to concentrate the study-on this,
class of compounds, which includes a
number of carcinogenic' and mutagenic
species (benzene, tetrachloroelhylene, eta).
These compounds were being extensively
studied in private homes in EPA's ongoing
Total Exposure Assessment Methodology
(TEAM) Study (Wallace 1987); therefore it was
decided to concentrate on buildings rather
than homes. Buildings where people spend
tang periods of time were selected for study:
schools, homes for the elderly, and office
buildings. These buildings also contain
populations (children, the elderly) that may
be more sensitive to air pollutants.
Study Design
The goals of the study were the following:
1) Identify all VOCs collected by the
available methodology (Tenax absor-
bent, GC-MS detection) on a subset of
samples, both outdoor and indoor.
2) Quantify a set of target VOCs'. selected
on the basis of their potential health ef-
fects, production volume, and amenabi-
lity to collection on Tenax, in all '
samples.
3) Determine the effect of aging on the
concentrations of VOCs within a newly
constructed building.
4) Measure emissions, of VOCs from
building materials and processes.
5) Measure concentrations of inhalable
particles, including metals, and air ex-
change rates in all buildings.
Four buildings were selected for study: two
homes for the elderly in Washington, DC; an
elementary school in Washington DC; and
an office building scheduled to be con-
structed in Research Triangle Park, NC. The
first three buildings were monitored once on-
ly, but the new office building was monitored
three times: immediately following comple-
tion of construction; two months later (after
the occupants moved in); and again five
months after completion of construction.
' Each monitoring visit lasted, two or three
days. From three to five indoor sites were
selected and one outdoor site (near the air
intake for-the building) was monitored over
consecutive 12-hour periods. Air exchange
rates were determined for each 12-hour
period by injecting sulfur hexafluoride (SF$)
Printed on Recycled Paper
-------
Snto the building ventilation system and
measuring tha decay in concentration.
aged 102% for all chemicals. Precision of du-
plicate samples averaged ± 25% (Table 1).
...: Measurement Methods ' ' ' ....... ' "
Mflasurenjent methods are described ful-
ly Jn the report. Following i .a brief
Description. ...............
1) \tofatileorganics. Mr samples were col-
tected in cartridges containing 15 g of 35/60
mesh Tenax™. 20 Nters of air were sampled
oyer each 12-hour period. Thermal desorp-
' lion" was followed by GC-MS analysis.
2) Panicles. Inhalabte particles including
both the fine (<2£^) and coarse (25-10/0
fractions were collected on dichotomous
samplers (using virtual impactton) and on
sampJars designed for EPA by the National
Bureau of Standards (using stack fitters). The
fitters were weighed by microbalance and
analyzed for metajs by proton-induced x-ray
^mission (PIXE),
Near-real-time particle measurements us-
ing the Ptezobalance"' were made at some
buildings to document short-term variations
fn particles caused by sources such as
smoking,
3) Emissions from materials. Headspace
vapors from heated materials in belljars were
coltected on Tenax cartridges arid analyzed
by GC-MS for the target compounds. Several
materials (paints, wallpaper, carpet,
adhesives) were then selected for analysis of
:j emissions in a room-size chamber (Pierce
" Foundation, Yale Univ.}. Materials were aged
for one week, placed in the chamber and
allowed to equilibrate for 24 hours, and their
organic emissions were then collected on
triplicate Tenax cartridges and analyzed by
GC-MS. One chamber experiment used
cleaning materials and an insecticide col-
lected from the supplies in the office building.
A technician applied detergent, chlorine
bleach scouring powder, and the spray insec-
ticide at Intervals during the sampling period
in the chamber.
Quality Assurance
Three blank Tenax cartridges from each
Tenax batch employed in the six monitoring
visits were analyzed for the target pollutants.
Three additional cartridges were spiked with
known amounts of the target compounds and
carried to the field and returned unexposed;
these wert then analyzed to determine
recovery efficiencies. Deulerated compounds
were toaded oh some cartridges as a further
check on recovery efficiency. Ten percent of
exposed cartridges were collected in
duplicate to determine sampling precision.
Results
Quality Assurance
Blank levels were low for all chemicals except
benzene. Median recovery efficiencies aver-
Qualitative Identifications
A total of 16 samples (12 indoor, 4 outdoor)
were analyzed to identify a broad spectrum
of VOCs occurring in the four buildings. More
than 500 chemicals were identified. Those
appearing most often include- aliphatic,
aromatic, and chlorinated compounds (Table
2).
A typical air sample contained 100-200
compounds. Of these, about 50 compounds
per sample were unique to that sample. In-
door samples were normally more complex
than outdoor samples.
Quantitative Results
A total of 165 Tenax samples were collected.
All four buildings had higher concentrations
of VOCs indoors than outdoors. For the three
older buildings, the indoor-outdoor ratio of
total organics was about 2 or 3 to 1. However,
this ratio was nearly 50 to 1 for the new of-
fice building immediately following construc-
tion. After two months, this ratio dropped to
about 10 to 1 and after an additional three
months, the ratio was about 5 to 1. Chemicals
at elevated levels in the new building includ-
ed aromatic compounds such as xylenes and
ethylbenzene, and aliphatic compounds such
as decane and undecane (Table 3).
Emissions from 16 materials collected from
the new office building were measured on a
semiquantitative basis using headspace
analysis. Between 13 and 111 organic
chemicals were identified from each material.
Common emissions included xylenes, ethyl-
benzene, decane and undecane, and 1,1,1-
trichloroethane. All but one of the 15 target
chemicals were emitted by one or more of
the materials. (The one exception was
tetrachioroethytene.)
Emission rates determined from the
chamber studies are displayed in Table 4.
The mixture of cleaning agents (liquid
detergent and a chlorine bleach scouring
powder) and a spray pesticide produced
large quantities of chlorinated compounds,
whereas the paint, carpet, and adhesives
produced primarily aromatic and aliphatic
compounds.
Fine particle mass averaged over 24-hour
periods ranged from 30-100 fig/m* in smok-
ing areas, compared to 10/ig/m3 in nonsmok-
ing areas, (Table 5). Short-term measure-
ments using the Piezobalance™ docu-
mented much higher concentrations (nearly
300 uglm3) during.smoking episodes in a
smoking lounge (Figure 1).
Air exchange measurements showed
typical ranges of 05 to 1 air change per hour
for two buildings (Table 6). One building, a
home for the elderly, had consistently- high
air exchange rates due to high negative
pressures created by excessive heating and
very cold winter temperatures.
Table 1:
Chemical
Recoveries. Blank Levels, and Precision for Target Volatile Organics
Blank
Recoveries" Levels'
(%Jl (ng/cartridge)
Median
RSD"
(%)
Chlorinated
Chloroform
1,2-Dichhroethane
1.1,1-Trichloroethane
Trichloroethylene
Tetrachioroethytene
p-Dichlorobenzene
Carbon Tetrachtoride
Aromatic
Benzene
Styrene
Ethylbenzene
o-Xytene
m+p-Xyfene
Aliphatic
Decane"
Undecane
Dodecane
Mean for all Chemicals
96
102
104
99
95
109
97
80
109
111
104
104
120
105
98
102 ± 9
5
NDF
12
2
ND
2
ND
36
6
2
1
4
ND
• 4
2
5± 9
37
7
31
20
16
20
23
35
40
23
25
25
30
22
22
25 ± 8
'Median of JB triplicate determinations.
"Relative standard deviation (N-17 duplicates)
cNot detected.
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Tabto 2: Most Cdmmon Organic Compounds at Four Buildings
Class/Compound n*
A/6
Aromatic Hydrocarbons
benzene
toluene
xylenes
styrene •
ethylbenzene
ethyl methyl benzenes
trimethyl benzenes .
dimethylethylbenzenes •
naphthalene
methyl naphthalenes '
propylmethylbenzenes,.
n-propyl benzene ~-
diethyl benzenes '
Halogenated Hydrobarbons
Tetrachloroethylene
7, 7, 1-trichloroethane
trichloroethylene
dichlorobenzenes
trichlorofluoromethane '
dichloromethane
chloroform , , . .
Esters
ethyl, acetate '' •.
m-hexyl butanoate
'Alcohols
.2-ethyl-1-hexanol
n-hexanol
.- 2-butyloctanbl
n-dbdecanol
•Aldehydes
n-nonanal
n-devansil .
Miscellaneous - '
acetone '
acetic acid . •
dimethylphenbls
ethylene oxide .
76
16
76
76
76
76
/6
75
75
75
14
13
12
.,
i 76
75
14
12
12
11
10
•-''.' ' 'a"
.4
9
8
7-
'•• ' 6'
73
, 70
16
10
-. 6
4
Aliphatics '•"- •
undecane
'_ 2-methylhexane
*2-methylpentane
'- 3-methylhexane •?..'•
3-methylpentane
octane, " • , • - • . .
nonane , \
decane '
-dodecane
tndecane
- methylcyclohexane .-••••••
' ' • heptane .
• tetradecane . .
2-methylheptane • •
cyclohexane .•
• pentadecarie
••- 4-methyldecane
2,44imethylhexane
pentane
hexane
eicosane
3-methylnonane -
1,3*timethyl- . :
cyctopentane
-! '
70
1 -.9-
9
9
' •- 9
9
• g
9
• • •'-. 9
9
9
. 8
- . '•• 8
- '8
8
7
7
7
6
6
6
6
•. /
.'-. 6
"Number of samples (of 16) with compound present.
"Number ol samples (of 10) with compounl present.
Discussion
Of the 500 chemicals identified in the four.
buildings, about half were found only once,
suggesting the presence of many small
sources rather than a few dominant ones.
Aliphatic hydrocarbons formed the most
.populous category of chemicals, with
aromatic hydrocarbons and chlorinated
hydrocarbons forming the next most
populous categories. Alcohols, acids.
ketones, aldehydes,'and esters were also
prevalent. It should be noted that the ob-
served chemicals did not include organics
more volatile than hexane or less volatile than
dodecane. Moreover, most polar compounds
were also not collected by the methodology
employed. Thus the observed VOCs were
only a portion of the total VOCs present.
As observed in the TEAM Study of in-
dividual homes (Wallace, 1987a), indoor con-
centrations of VOCs in buildings exceed out-
door concentrations for all of the prevalent
target chemicals. The TEAM Study findings
implied that the source of the higher indoor
concentrations might be emissions from
building materials, consumer products, or in-
door processes such as cleaning or smok-
ing. The present study documents that the
19 materials and several processes studied
emit essentially all of the observed target
chemicals. The question of what proportion
of the observed concentrations might be at-
tributed to the materials, and processes tested
has been treated more fully in Wallace, 1985.
That paper concludes that many of the target
chemicals are emitted by a very large num-
ber of materials and processes,:and'that
.therefore the observed concentrations may
often be due to small contributions from
many sources. These findings are in good
' agreement with the later more extensive
studies of 31 building materials carried out
in the EPA companion,study of six buildings
(Sheldon, 1987; Wallace, 1987b; Jungers, 1987,)
The new office building had concentrations
of five aromatic and aliphatic hydrocarbons
that were two orders of magnitude greater
than the concentrations observed 5 months
later. Half-lives of the five chemicals ranged
from 2-8 weeks (Pellizzari, 1984; Wallace ef
a/., 1987). Thus the time required for this
building to approach the outdoor concentra-
tions would range from 3-12 months. This fin-
ding supports the Scandinavian decision to
require 100% outdoor air as makeup air for
the first 6 months of a new building's life.
Fine panicle mass was strongly affected
by smoking. Levels in smoking lounges and
apartments ranged from 20-90 ^g/m3 greater
than in nonsmoking areas. One apartmert.
with with two heavy smokers had 24-hour-
average levels of up to 100 ^g/m3. These fin-
dings are similar to those in the extensive
series of studies carried out by Spengler and
coworkers in -the Harvard 6-City Study
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T*«t 3: VolttHe Orgatfcs in a Now Office Building'
Concentration (ng/m*)
WV--4.., Indoors1 Outdoors*
*ct»mic*i July Sepf. Dec a//7nps
. AJiphwics
£•*">• 3ao 38 ^ ' 2
"J^» . 770 48 73 . 1 •
DodK*» 47 19 5 02
Aromtlics . .
m+p-Xyfcn* 740 79 's 2
o-Xyiute 74 e 4 j
£ttyi>*ur*>» w 6 , J
•f«w» 5 7 7 3
SrynKW a 7 4 ,
Httoearbora
i,1,1'Tricahmttham 3SO 700 49 e
T«ertcWoro»Ojyteo» .7 2 3 r
TWeAtoroathytoo* * 7 38 27 03
Cartwj r«6*tf*vfcte j 7 7 ,
CMorofofffl 1 ' 2 78 6
MXchtofobanzene 7 7 1 ND
Total of 14 Optwcs , 7300 326 750 25~
•«•**! of «x JS-ftow *wa9»s *f ffv» tabor fcc*tion.s.
**<*»» o< /8 72-ftx/r «v»/ip« M am outdoor locttion.
T«W» 4.- Emission Rates From Various Selected Sources
Emission Rate (ng/min/m>)
_. . , Cleaning Agents Painted Glued Glued
JXHHnical and Insecticides Sheetrock Wallpaper Carpet
CnKfOform 1S,000±2SO (1.5)* ND" ND ND
I'ffSSf?"'"^* 12'°°° ND 310±46 (15) 180+12 (7)
1,1.1-Tnchhmethane 37.000 ±15.000 (42) 31±15 (47) 84±48 (57) 260+31 (12)
BtmOM ND 120±29 (25) ND ND
Ctrixm Tttrachtoride 71,000±5.300 (7.5) ND ND ND
7/fchtoro«%to/» 370±47 (3.8) ND ND ND
TttrtcnlorotthytenB ND ND ND ND
Cktorobomtn* ND ' ND ND ND
Ethytoetuene ND ND ND 77+39 (50)
P^W ND ND 26±6.5 (25) 1SO±24 (16)
®y?* ND • ND ND 98±14 (15)
*?? ND ND 6.5±3.1 (50) 98+26 (27) ,
m-DKMorobonzerm 560±20 (3.6) ND ND ND
O^ichhfoberaene 440±S (1.2) ND ND 41 ±14 (36)
rvOtca/w 770±27 (16) 240±29 (12) 190±77 (40) 545 ±150 (28)
oJXchforobemera ND ND ND ND'
n^nctoca'» r.700±0 (0) 1500±3SO(24) 300 ±110 (36) 500 ±150 (30)
•Cotttic»nt ot vintiK* (to). N . 3 observitions. ±SD (CV). N - 3 oteervatois.
*ND m not cfcftcwd (vOots mn in no/mm/my,
T«W« S.' Rtspirable Particles at Two Homes for the Elderly
Loc*'*™ Concentration (vglm^f
Home #2 Home#1 ,
Smoker's Apartment • .89 39
Commons Area 76* 30c
Nonsmoktf's Apartment g g
Outdoors ' 4" 10
•MMO of then con&cutivt 24J>our umptes.
*Sotn» smohng obnrvtd
^ptc*«tf tmotung lounge
Ont U-rxwr stmph
considerably greater for these chemicals in
indoor air than in outdoor air or, (except for
chloroform), in drinking water. The risks
associated, with the type of buildings studied
here would be smaller by the ratio of the time
spent in them to the time spent in homes.
The second type of health effect is acute,
consisting of eye, nose and throat irritation,
headaches, neurotoxic symptoms such as
depression, irritability, and forgetfulness, and
general malaise— a group of symptoms often
described as "Sick Building Syndrome"
(SBS). Although the cause or causes of SBS
are unknown, several hypotheses implicate
tow-level concentrations of VOCs as a possi-
ble cause (Berglund, 1982; Molhave, 1984).
The economic effect of SBS may be con-
siderable, if a large proportion of workplaces
.are affected. One nationwide survey has
reported that 25% of American workers feel
the quality of air at their workplace affects
their work adversely. If so, economic produc-
tivity may be lowered by a significant amount.
Conclusions
At least 500 volatile organic compounds
have been identified in indoor air in four
buildings. These indoor air samples contain-
ed from 100 to 200 VOCs, often at levels that
were several times the outdoor concentration.
The sources of these elevated indoor air "con-
centrations included building materials, con-
sumer products, and processes such as
cleaning and smoking. The materials tested
emitted between 18 and 111 VOCs at rates
ranging up to 1000 ^g/m2/h.
Concentrations of individual aromatic and
aliphatic compounds such as xyienes and
decane were elevated over outdoor levels by
factors of 100 in the new building studied.
Half-lives of these compounds ranged from
2-8 weeks. The time to reach concentrations
comparable with outdoor levels was
estimated at 3-12 months.
Concentrations of fine-particulates were
elevated by 20-70 uglrrfl in smoking areas.
Recommendations
This study has indicated that concentra-
tions of certain target VOCs are elevated in
buildings due to emissions from certain
building materials. Only four buildings were
monitored and only 16 building materials
were tested for emissions. Considering that
the building stock in the U.S. is more than
3 million, and that building materials and con-
sumer products probably number in the hun-
dreds of thousands, it is clear that only the
surface has been scratched in this study.
Many more buildings of various types
(hospitals, enclosed shopping malls, etc.)
where people spend a considerable fraction "
of their time should be monitored before it
will be possible to estimate the frequency
-------
Figure 1. Respirable particulales in smoking lounge of the elderly home « ; (3/24/83).:
360
320
280
. 240
I
•I-
200
160
120-
80.
40-
Nine Smokers
Three Smokers
No Smokers
Present
:1
Mean Concentration
in nonsmoking area
5:00 PM
5:30
6:00
6:30
Time
distribution of VOC concentrations in such
buildings. Many more building materials
should be tested to determine their rates of
emission of chemicals of concern-before a
trustworthy estimate of the range.of emission
rates can be.achieved.
Table 6: Air Exchange Rates at Three
Buildings
Building
Elderly Home #7
School
Office (July)
Office (September)
Air Exchange Rate*
(ach)
1.72 ± 0.41
0.85 ± 0.31
0.61 ± 0.32
0.52. ± 0.25
'Mean of 4-6 measurements over consecutive 12-4mur
periods at each ol 3-4 indoor fccMbns in each txOOing.
An economic study of the effects of indoor
air quality on productivity would help to clarify
the magnitude of the indoor air quality pro-
blem in the office and workplace
environment.
References
Berglund, a, Berglund, U, UndvaK.T. and
Nicander-Bredberg, H. (1982), "Olfactory and
Chemical Characterization of Indoor Air—
Towards a Psychophysical Model for Air
Quality" Environ. Int. 8: 327-332.
Jungers. R. H. and Sheldon, L.S. (1987)
"Characterization of Volatile Organic
Chemicals in Public Access Buildings" in In-
door Air '87: Proceedings of the 4th Interna-
tional Conference on Indoor Air Quality and
Climate, August 17-21, 1987. Vol. 2, pp.
144^148. institute for Water, Soil, and Air
Hygiene. W. Berlin.
A/lolhave, L., Bach, B. and Pederson, O.F.
• (1984) "Human reactions during controlled
exposures to low concentrations of organic
gases and vapours known as normal indoor
air pollutants" in Berglund, &K Lindvall, T and
Sundell, J. eds. Indoor Air: Sensory and
Hyperreactiyity Reactions to Sick Buildings.
Volumes, pp. 431-436. Swedish Council for
Building Research, Stockholm, Sweden.*
National Academy of Sciences. (1986) En-
vironmental Tobacco Smoke: Measuring Ex-
posures and Assessing Health Effects, Na-
tional Academy Press. Washington, DC.
, Pellizzari, E.D., Sheldon, L. S., Sparacino,
C.M., Bursey, J.T., Wallace, L and Bromberg,
S. (1984) "Volatile Organic Levels in Indoor .
Air," in Berglund, B., Lindvall, land Sundell,
J. eds. Indoor Air: Chemical Characterization
' and Personal Exposure, Volume 4 pp.
303-308. Swedish Council for Building
Research, Stockholm, Sweden.
Repace, J. L. and Lowrey, A. H. (1980) "In-
door Air Pollution, Tobacco Smoke, and
Public Health," Science 208:464-472.
Repace, J. L. and Lowrey, A-.H-. (1985) "A
Quantitative Estimate of Nonsmokers' Lung
Cancer Risk from Passive Smoking" Environ.
Int. 11:3-22
Sheldon, L. Zeton.H., Sickles, J., Eaton
C. and Hartwell, T. (1988) Indoor Air, Duality
in Public Buildings: Volume II, Environmen-
tal Monitoring Systems Laboratory, US EPA
Research Triangle Park, NC.
Spongier, J.D., Treitman, R.D., Tosteson,
T.D., Mage, D.T., and Soczak, M.L., (1985)
"Personal Exposures to Respirable Par-
ticulates and .-Implications for Ambient Air
Quality Standards and' Health Effects
Research," Environ.Sci. 4:347-35a
Tancrede, M., Crouch, E., Zeise, L and
Wilson, 8. (1987) 'The Carcinogenic Risk of
Some Organic Vapors Indoors: A Theoretical '
Survey," Atmos. Env. 21: 2187-220&
Wallace, L., Bromberg, S., Pellizzari, E.,
Hartwell, T, Zeton, H.. and Sheldon, L. (1984)
"Plan and preliminary results of the U. S. En-
vironmental Protection Agency's Indoor Air
Monitoring Program: 1982" i;» Berglund, B.,
Lindvall. T. and Sundell, J. eds. Indoor Air: .
Recent Advances in the Health Sciences:and
Technology: Volume 1 pp. 173-178. Swedish
Council for Building-Research, Stockholm.
.Sweden. ..'•-..
Wallace, L. A., Pellizzari. E.D.. Leaderer,
EL P., Zeton, H. and Sheldon. l_ (1985) "Emis-
-------
sions of Volatile Organic Compounds from
Building Materials and Consumer Products"
Atoms Em. 21:385-39a
Wallace. Lance A. (1986} "Cancer Risks
from Organic Chemicals in the Home" in En-
vironmental risk management—Is Analyis
Useful?, Proceedings of an APCA Interna-
tional Specialty Conference, pp. 14-24. Air
Pollution Control Association, Pittsburgh, PA.
Wallace, L, dangers, R., Sheldon, L, and
Pellizzari, E. (1987) "Volatile Organic
Chemicals in 10 Public-Access Buildings" in
Indoor Air '87: Proceedings of the 4th Inter-
national Conference on Indoor Air Quality
and Climate, August 17-21. 1987. Vol. 2, pp.
188-192. Institute for Water, Soil, and Air
Hygiene, W. Berlin.
Wallace, L. (19S7a) The Total Exposure
Assessment Methodology (TEAM) Study:
Summary and Analysis—Vol. I.
EPA/600/6-877002a.
Wallace, L. (1987b) "Emission Rates of
Volatile Organic Compounds from Building
Materials and Surface Coatings" in Pro-
ceedings of the 19S7 EPA/APCA Symposium
on Measurement of Toxic and Related Air
Pollutants, pp. 115-122. Air Pollution Control
Asociation, Pittsburgh, PA.
Ware, J.H., Dockery, D.W., Spiro, A.,
Speizer, F.E., Ferris, B.G., Jr. (1984) "Passive
Smoking, Gas Cooking, and Respiratory
Health of Children Living in Six Cities" Amer.
Rev. Respir. Dis. 129:366-374.
L S. Sheldon, R. W. Handy. T. D. Hartwell. R. W. Whitmore. H. S. Zelon. and
£, D. Pellizzari are with Research Triangle Institute, Research Triangle Park,
NC 27709.
Lance Wallace is the EPA Project Officer (see below}.
The complete report, entitled "Indqpr Air Quality in Public Buildings: Volume
I." (Order No. PB 89-102 503/AS; Cost: $44.95. subject to change) will be
available only from:
National Technical Information Service
B28S Port Royal Road
Springfield, VA 22161
Telephone: 703-487-4650
The EPA Project Officer can be contacted at:
Office of Acid Deposition, Environmental Monitoring and Quality
Assurance
U.S. Environmental Protection Agency
Washington. DC 20460
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