PROCEEDINGS
THIRD US-JAPAN CONFERENCE
PHOTOCHEMICAL AIR POLLUTION
September 3-10, 1976
USEPA Research Center
Research Triangle Park, N.C.
. DELEGATION
'. A.P. Altshuller, Chairman
.vironmental Sciences Research Laboratory
IEPA
•. B. Dimitriades
.vironmental Sciences Research Laboratory
IEPA
•. K. iMaconaughey
fice of International Activities
;EPA
.JAPANESE DELEGATION
Mr. Ksi Yarr.azaki, Chairman
Environment Agency
Dr. Naomi Y=i:naki
SaitaiuO University
Dr. Michio Okuds
National Institute for
Environmental Studies
Dr. Machic Okita
Institute of Public Health
Dr. Isao Mizuchi
Tokyo Metropolitan
Laooratory for Public Health
Mr. Toshiaki Shimazaki
Snvironir.ent Agency
ENVIRONMENTAL SCIENCES RESEARCH LABORATORY
U.S. ENVIRONMENTAL PROTECTION AGENCY
RESEARCH TRIANGLE PARK, N.C. 27711 USA
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PROCEEDINGS
THIRD US-JAPAN CONFERENCE
ON
PHOTOCHEMICAL AIR POLLUTION
September 8-10, 1976
USEPA Research Center
Research Triangle Park, N.C,
US DELEGATION
Dr. A.P. Altshuller, Chairman
Environmental Sciences Research Laboratory
USEPA
Dr. B. Dimitriades
Environmental Sciences Research Laboratory
USEPA
Mr. K. Maconaughey
Office of International Activities
USEPA
.JAPANESE DELEGATION
Mr. Kei Yamazaki, Chairman
Environment Agency
Dr. Naomi Yamaki
Saitamo University
Dr. Michio Okuda
National Institute for
Environmental Studies
Dr. Machio Okita
Institute of Public Health
Dr. Isao Mizuchi
Tokyo Metropolitan
Laboratory for Public Health
Mr. Toshiaki Shimazaki
Environment Agency
ENVIRONMENTAL SCIENCES RESEARCH LABORATORY
U.S. ENVIRONMENTAL PROTECTION AGENCY
RESEARCH TRIANGLE PARK, N.C. 27711 USA
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INTRODUCTION
Dr. Altshuller, head of the U.S. Delegation, welcomed the delegated and discussed
/
briefly the history of the joint panel activities. He referred to the previous
Conference conclusions, one of which was that the US and Japan exchange scientific
information on the oxidant pollution problem. It was specifically agreed in the
Second Conference that the scientific basis supporting the oxidant and NO
control strategies in the two countries should be described, and discussed by
the respective delegations. Such discussions constitute the program of the
Third Conference.
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AGENDA
THIRD US-JAPAN CONFERENCE
ON
PHOTOCHEMICAL AIR POLLUTION
U.S. Environmental Protection Agency
Environmental Sciences Research Laboratory
Environmental Research Center
Research Triangle Park, N.C. 27711, USA
September 8-10, 1976
Wednesday, September 8, 1976: Session Chairman: Dr. Altshuller
10:00 a.m.
10:30 — 11:00
11:00 — 11:30
11:30 -- 12:00
12:00 -- 1:30
1:30 — 2:00
2:00 -- 2:30
2:30 — 3:00
3:00 — 4:00
4:00 -- 4:30
Welcome
Introduction of Participants
Election of Chairmen
Discussion and Approval of Meeting
Program
Coffee -- Refreshments
Impact of Hydrocarbon Emission
Control in the U.S.
(Introduction)
Discussion
Lunch
Impact of Hydrocarbon Emission
Control in the U.S.
Discussion
Coffee -- Refreshments
Outdoor Smog Chamber Studies
In the U.S.
.Discussion
A.P. Altshuller
Kei Yamazaki
Naomi Yamaki
A.P. Altshuller
A.P. Altshuller
B. Dimitriades
U.S. EPA
B. Dimitriades
U.S. EPA
H. Jeffries
U. North Carolina
11
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Thursday, September 9. 1976: Session Chairman: Dr. Kei Yamazaki
9:00 -- 9:15 Opening Remarks Dr. Kei Yamazaki
9:15 -- 9:45 Results of Smog Chamber Studies Japanese Delegation
In Japan
9:45 -- 10:15 Discussion
10:15 -- 10:45 Coffee -- Refreshments
10:45 — 11;15 The Strategy for Oxidants and Japanese Delegation
N0£ Control in Japan
11:15 — 12:00 Discussion
12:00 — 1:30 Lunch
1:30 -- 4:30 Tour, ERC - RTF
Visit University of North Carolina and
Research Triangle Institute Outdoor Smog
Chamber Facilities
Friday. September 10, 1976: Session Chairman: Dr. Altshuller
10:00 -- 10:15 Opening Remarks Dr. Altshuller
10:15 — 10:45 Results of Studies in Japan Japanese Delegation
on Health Effects of Oxidants
10:45 -- 11:15 Coffee -- Refreshments
11:15 -- 12:00 Discussion
12:00 -- 1:30 Lunch
Session Chairman: Dr. Kei Yamazaki
1:30 -- 3:00 Plans for Future Activities
3:00 -- 3:30 Coffee -- Refreshments
3:00 -- 4:00 General Discussion
Joint Communique
Conclusion of Meeting
m
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•JOINT COMMUNIQUE
The Third U.S. -- Japan Conference on Photochemical Air Pollution
was held in Research Triangle Park, North Carolina on September 8-10,
1976.
The Japanese delegation included: Mr. Kei Yamazaki General Chairman,
Environment Agency; Dr. Naoomi Yamaki -- Saitama University; Dr. Michio
Okuda -- National Institute for Environmental Studies; Dr. Toshiichi
Okita --Institute of Public Health; Dr. Isao Mizoguchi -- Tokyo Metropolitan
Research Laboratory of Public Health and Mr. Toshiaki Shimazaki --
Environment Agency.
The principal United States delegates were: Dr. A.P. Altshuller,
General Chairman, EPA; Dr. B. Dimitriades, EPA, and Mr. K. Maconaughey,
EPA.
Discussions were centered around subjects agreed upon by the two
delegations during the Second Conference held in November 17-21, 1976,
and in subsequent communications exchanged by the two delegations. Such
subjects included:
1. The Strategy for Oxidants and NO, Control in Japan
2. Results of Smog Chamber Studies in Japan
3. Results of Studies in Japan on Health Effects of Oxidants
4. Impact of Hydrocarbon Emission Control in the U.S.
5. Outdoor Smog Chamber Studies in the U.S.
The most notable scientific findings and viewpoints presented and
discussed in the Conference are summarized as follows:
1. The current Japanese strategies for control'of oxidant and of
N0_ evolved from consideration of several scientific findings.
Principal scientific evidence relevant to the need for N07 control
was obtained from studies of health effects associated with N0_.
The N0_ control strategy is based on control of NO emissions.
Evidence relevant to the question of oxidant control strategy
consists of air monitoring and smog chamber data, and, overall,
suggests HC control as an approach to ambient oxidant reduction.
2. The evidence currently available in the US strongly suggests
that when sufficient and reliable data are available, it can be
demonstrated that HC control in the last decade had a beneficial
effect upon oxidant air quality in the core areas of urban centers.
IV
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The two delegations agreed on a continuing cooperative program with
immediate and specific interest in exchange of scientific evidence and
expertise in the area of smog chamber and field studies of the photochemical
pollution problem. More specifically, it was agreed to continue the
effort to generate and exchange comparable data and procedures including
possible scientific personnel exchange.
It was tentatively agreed to call the next meeting in the fall of
1977.
Dr. A.P. Altshuller Mr.- Kei/Yamazaki
General Chairman Gener'a-I Chairman
U.S. Side Japanese Side
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TABLE OF CONTENTS
Introduction .............................. i
Adgenda of Meeting ............................ i"1'
Joint Comminique ............................. 1V
Technical Papers
1. Impact of Hydrocarbon Emission Control
in the U.S. (Dimitriades) ................... 1
2. Outdoor Smog Chamber Studies in the U.S.
(Jeffries) ........................... 21
3. The Concept of Prevention of Photochemical
Oxidants -- With Reference to Results of Smog
Chamber Experiments (Environment Agency -- Japan) ....... 35
4. Nitrogen Oxides Control Measures in Japan
(Environment Agency — Japan) ................. 51
5. Measures Being Taken in Japan to Reduce N02
and Photochemical Oxidant in the Air
(Environment Agency -- Japan) ................. 82
6. Experimental Results of a Mobile Smog
Chamber (Environment Agency -- Japan) ............. 151
7. Health Hazards of Photochemical Air Pollution
(The results of a survey on health hazards
of photochemical air pollution in 1975.)
(Environment Agency -- Japan) ................. 224
8. Photochemical Oxidants Control Measures in Japan
(Environment Agency -- Japan) ................. 265
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IMPACT OF HYDROCARBON EMISSION CONTROL IN THE U.S.
Basil Dimitriades
Environmental Sciences Research Laboratory
U.S. Environmental Protection Agency
Research Triangle Park, N.C. 27711
ABSTRACT
Studies conducted in various parts of the US on the impact of
hydrocarbon emission control upon oxidant air quality met with various
degrees of success. Thus, observed air quality trends in some cases
could and in others could not be explained by emission control. The latter
diffculty appears to be caused by a host of interfering effects that
cannot be delineated unless an abundance
of valid air quality and emission data are available. In two areas --
Los Angeles and San Francisco, California --for which adequate data were
available, it was shown (a) that urban air quality trends could be
explained by emission changes, and (b) that hydrocarbon emission control
was the cause of observed air quality improvement.
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INTRODUCTION
Hydrocarbon emission control for ambient oxidant reduction was
intitiated in the U.S. in 1961 when the automobile manufacturers voluntarily
installed crankcase controls on all new 1961-model cars sold in California.
Since then mandatory hydrocarbon control was enforced and expanded to
cover the entire U.S. and to include most types of mobile and some types
of stationary emission sources. With the passage of the Clean Air Act
of 1970, EPA was empowered (a) to establish a NAAQS for oxidant/0 to be
achieved through hydrocarbon emission control, and (b) to require a 90-
percent control of hydrocarbon emissions from automobiles and (c) to set
up a mechanism for air quality management (Submission of State Implementa-
tion Plans}. Notwithstanding the controls in the 1960's the levels of
hydrocarbon emissions in the US continued to increase as a result of
growth, and began declining only in the early 1970's. Table 1 shows
estimates of national emissions of hydrocarbons from mobile and stationary
sources projected through 1985. The important deduction from these
estimates is that the emissions from the stationary sources are becoming
the dominant ones, and,hence, stationary sources are the most promising
area where additional emission control can be achieved.
Table 1. Nationwide Hydrocarbon Emissions (millions of tons per year)
Year Mobile Stationary Total HC
Sources Sources Emissions
1972 16.6 12.5 29.1
1975 15.2 13.7 28.9
1985 10.4 14.7 25.1
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From laboratory dtudies of the oxidant formation process it has been
established unequivocally that for oridnary urban atmospheres control of
the HC precursor will have a beneficial impact upon urban oxidant air
quality. Aerometric data taken in real atmospheres verified the beneficial
nature of the HC control effect but failed to provide reliable quantitative
estimates. The reason for the latter problem is that in the real atmosphere
the effect of HC reduction is masked, partially or totally, by effects
from changes in NO emissions, from changes in HC, composition, from
A
changes in meteorological conditions, and from shifts in population or
industrial activity. The complexity of the problem is illustrated in
several atmospheric studies conducted in the US in the recent years.
These studies and their findings are summarized next.
ATMOSPHERIC STUDIES ON IMPACT OF HYDROCARBON
CONTROL ON OXIDANT AIR QUALITY
The approach commonly used in the studies conducted to date on the
impact of HC control consists of deriving air quality and precursor
emissions trends in a locality and examining such trends for evidence
suggestive of emissions effects. Obviously, this approach will be valid
only in those cases for which local oxidant and emissions are linked
through a cause-effect relationship that is, when the local emissions
are the cause of the oxidant observed. When pollutant transport causes a
significant part of the locally observed oxidant then air quality and
emission trends, unless carefully examined in conjunction with air
movement data, will be inconclusive.
The first systematic examinations of oxidant air quality trends
were conducted and reported by the State of California (1) and by Altshuller
(Figures 1-3) (2). The State of California reported Los Angeles basin
data showing the oxidant levels to decline (in the recnet years) more
rapidly in the coastal areas than in the inland areas. The Althsuller
analysis showed that in the CAMP cities also, center-city oxidant levels
declined in the recent years. The two reports made the following important
observations:
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1. Aerometric data on oxidant and precursor concentrations should
be carefully examined for quality and completeness before they
are used;
2. More than one indices for oxidant air quality should be used;
s
e.g. highest or second highest oxidant concentration, number
of days with oxidant exceeding 0.08 ppm, etc.;
3. Air quality trends in the source-intensive center-city areas
are not necessarily the same — in intensity or even direction --
as in the downwind suburb and/or rural areas.
While the two studies strognly suggested that the observed air
quality trends reflected emission control impact, no attempt was made to
quantitatively relate such trends to changes in emissions an/or other
relevant factors.
In a subsequent study conducted by the California Institute of
Technology, the researchers used a more rigorous and detailed investigative
approach (3,4) Specifically, they derived air quality trends for several
locations within the Los Angeles air basin and attempted to explain such
trends in terms of effects from hydrocarbon emission control, NO emission
A
control, emission source growth, geographical distribution of emissions,
and meteorology. Findings from that study are summarized and illustrated
in figures 4 - 10.
Figure 4 shows the area covered by the Los Angeles air basin and
the geography of the six county sub-areas for which air quality and
emission trends were derived. Figure 5 shows population and automobile
traffic (VMT) growth rates within te basin and its subparts during 1967-
1974. Fagures 6 and 7 percent the hydrocarbon and NO emission trends
Jv
during the same decade. The NO increase reflects partly growth and
X
partly a side effect of the control techniques used to reduce HC and CO
from atuomobiles. From figures 5-7, two significant observations can be
made:
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4
(a) Growth rate is not uniform within the LA basin; it is low in
downtown Los Angeles (DOLA) and high in the areas sourrounding
DOLA.
(b) Consistent with these growth patterns and with the expected
effects of emission control, hydrocarbon emissions decreased
most in DOLA and least in surrounding areas; coversely, NO
emissions increased most in the surrounding areas and least in
DOLA.
Such non-uniform occurrence of emission changes should also have
non-uniform effect upon the basin's air quality. However, before this
is examined, it would be necessary to first verify that the trends in
ambient HC and NO concentrations are consistent with the emission
x
trends. These trends are shown in figures 8 and 9. These figures show
excellent agreement between emission and ambient concentration trends
for NO , and one case of disagreement between ambient HC trend in Azusa
and ambient HC and emission trends elsewhere in the LA County (Fig 9).
Oxidant air quality trends are illustrated in figure 10 and are
also compared with those in HC and NO emissions. The significant
X
observations to be made from Figure 10 are as follows. First, basinwide,
the ambient oxidant reduction is nearby equal to the HC emission reduction,
namely, 19% and 18% respectively. Second, in the individual localities,
oxidant changes and HC emission changes agree qualitatively, at least, in
the sense that Los Angeles County experienced the greatest improvement
in both oxidant concentration and HC emissions. Finally the coastal
areas seem to have experienced greater improvement in oxidant air quality
than the inland areas; in fact, in some inland localities air quality
deteriorated.
These oxidant trends can be explained reasonably well based on what
is known about the relative roles of the HC and NO precursors in the
oxidant formation process. Thus, control of HC should cause oxidant
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reduction in all localities where oxidant is caused by local emissions.
Such localities are the ones in coastal areas; HC control did indeed
cause oxidant reduction in those areas. Increase of NO is expected to
A
have a beneficial effect in the coastal areas; in the inland areas the
effect could be either beneficial or detrimental, as illustrated in
Figure 11. This explains the small improvement or deterioration'of air
quality in the inland areas.
In conclusion, the Los Angeles data show:
(a) Significant reduction of HC emissions was achieved in the LA
basin
(b) A degree of 0 reduction was observed that appears to be
Jt
consistent with the expected effects of HC reduction and accompanied
NO increase.
A
The LA situation makes perhaps the best case for the beneficial
impact of HC control upon oxidant air quality; however, Los Angeles is
not a typical urban area in the U.S. For a more reliable assessment of
the effect of HC control it is necessary that other areas in the US be
studied in a manner similar to the LA study. Such studies have been
attempted recently but without much success, mainly because these studies
have extremely high demands in air quality and emission data, and such
complete data are not usually available. One such attempted study was
conducted recently under EPA contract and is briefly summarized as
follows (5).
The locations studied were:
Urban: San Francisco, Philadelphia, Denver
Non-urban: Redding, San Joaquin Valley, Salinas, Lancaster
(all in California)
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6
In the first attempt data were used that covered a 5 year period
(1970-74). Results showed that only San Francisco and Denver experienced
a significant downward trend in oxidant air quality. In the case of
Denver the trend wasd weaker and was not paralleled by all oxidant
indices (average daily maximum in year). Correlation between oxidant changes
and emission changes were overall fairly good for SF, the correlation with
HC/NO being much better than with HC alone. In Denver, the correlations were
A
poor but the emission data available were also very inadequate, a fact that
might be the cause of the poor correlations.
In a second attempt an analysis was made of data for San Francisco
covering a longer period of 13 years (1962-1974). This analysis gave
more conclusive results, namely:
1. Downward trend in oxidant was much better defined
2. Correlation between oxidant trend and HC/NO -emission trend
was much better.
3. Weather variables did affect air quality trends; when data were
used for days meeting the smogginess criteria (high T, low
mixing height), the effects f emission changes could be seen
much more clearly.
4. Coastal areas have less severe 0 problems than inland areas
(ventilation, NO effect)
J\.
5. Monitoring data for a 5-year period are not enough to establish
air quality trends for an individual monitoring station.
Overall, the main conclusions from this study were that(
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(a) to reliably assess the impact of emission control in air
quality, an abundance of data (stations, years) need to be
used.
(b) when such data are available then the emission control impact
can be assessed and it appears to relate to HC/NO change
rather than to the HC-change.
It is perhaps because of the first conclusion that other studies
failed to show significant relationship between emission changes and air
quality changes. Thus, for example one and two-year studies in urban
areas of Texas failed to show any significant correlation between ambient
oxidant and emissions (figure 12) (6). Lack of such correlating may also
result from failure to properly consider pollutant transport. Thus,
there have been several studies of various parts of the U.S. that have
shown no correlation betweeen local oxidant and locally observerd meteoro-
logical and emission factors (6). When all these interfering effects
are understood and when there are sufficient data to permit delineation
of these interfering effects, then the impact of emission control can be
and has been determined.
REFERENCES
1. State of California, Air Resources Board. Hydrocarbon, Oxides of
Nitrogen and Oxidant Trends in the South Coast Air Basin (1963-
1972). 1973.
2. JAPCA, 25, pp 19-24, Jan. 1975.
3. J.C. Trijonis, T.K. Peng, G.J. McRae, and L. Lees. Emissions and
Air Quality Trends in the South Coast Air Basin, EQL Memorandum No.
16, Calif. Institute of TEchnology, Jan. 1976.
8
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4. Trijonis, J. , T. Peng, G. McRae, and L. Lees. Oxidant and Precursor
Trends in the Metropolitan Los Angeles Region. Proceedings of
International Conference on Photochemical Oxidant Pollution and Its
Control. USEPA, ESRL, Research Triangle Park, N.C. 1976.
5. Wayne, L.G., K.W. Wilson, and C.L. Boyd. Detection and Interpretation
of Trends in Oxidant Air Quality, Pacific Environmental Services,
Inc. Report to USEPA under Contract 68-02-1890, July 1976.
6. Air Pollution Control Association, Southwest Section. Proceedings
of Specialty Conference on Ozone/Oxidants. Interactions with the
Total Environment, p. 26, p. 38, p. 282. March, 1976.
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18
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Figure 2
POLLUTANT TRENDS IN SAN BERNARDINO, 1963-1972
ANNUAL AND THREE-YEAR MOVING AVERAGES
FOR JULY, AUGUST &'SEPTEMBER
11
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Figure3r Trend in oxidant results by year at CAMP sites.
12
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.SANTA BARBARA
VENTURA
\ LOS ANGELES
SAN BERNARDINO
MAP OF SOUTH COAST AIR BASIN-
FIGURE 4
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POP: +1,57,
VMT: +6,3%
I POP: +3,6%
VMT: +2,8%
POP: +0,3%
VMT: >M%
POP: +1,3%
/
VMTs +5,5%
POP: +2,6%
BASINWIDE VMT: +3,9%
BASINWIDE POPULATION: +1.1%
AVERAGE YEARLY VMT AND POPULATION GROWni RATES, 1965-1974
FIGURE S
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en1
/ SAN- BERNARDINO
RIVERSIDE
BASINWIDE NOX EMISSION CHANGE: (+36%,
TRENDS IN NOX BUSSIONS, 1965-1974
FIGURE 6
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BASINWIDE RHC EMISSION CHANGE: (-18%
TRENDS IN RHC EMISSIONS, 1965-1974
FIGURE 7
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16
BASINKIDE NOX EMISSION CHANGE: (+36"
AVER-\GU KTx CONCENTRATION CHANGE C 11 STATIONS) : »JS\
^Figures Trends in NOX Emissions, and Air Quality, 1965-1974
., L . . .
BASINWIDE RHC EMISSION CHANGE: (-18Z
AVERAGE NMHC CONCENTRATION CHANGE (4 STATIONS)
Figure 9 Trends in RHC Emissions and Air Qua! ity,~1965-1974
17
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BASINWIDE RI1C EMISSION CHANGE: -
BASIN'IVIDE NOX EMISSION CHANGE: (+36%)
AVERAGE OXIDANT CONCENTRATION Ql\KGE (13 STATIONS): -19*
TRENDS IN RHC EMISSIONS AND OXIDANT AIR QUALITY. 196S-1974
FIGURE 10
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Figure 11. Effect of NO on peak-oxidant level and locations
A
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OXIDANT (LOW NOX)
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OXIDANT (HIGH NOX)
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LOCATION KEY
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Figure 12 Scatterplot of Changes in Ozone Levels and
in Man-Made Hydrocarbon (HC) Emissions
(197>»-T5)
20
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OUTDOOR SMOG CHAMBER STUDIES IN THE US
by
Harvey E. Jeffries
Department of Environmental Sciences and Engineering
School of Public Health
University of North Carolina
Chapel Hill, N.C. 27514
INTRODUCTION
Outdoor smog chamber studies, sponsored by the Environmental Protection
Agency (EPA), have concentrated on simulation aspects of air pollution control
strategies under reasonably realistic conditions. Special emphasis has been placed
on the effects of hydrocarbon concentration reductions on nitrogen dioxide (NOg)
and ozone (03) concentrations.
Presently, there are two groups of outdoor chambers, one set operated
byt he University of North Carolina (UNC) at a rural site approximately 35 miles
from the Research Triangle Park (RTP), and one set operated by the Research
Triangle Institute (RTI), located in RTP.
CHAMBER DESCRIPTIONS
The UNC chambers consist of one dual compartment, very large chamber
intended primarily for gas phase studies, and a slightly smaller, single
compartment chamber, intended primarily for aerosol studies. The cahmbers are of
similar design and construction, therefore, only the gas chamber will be
described.
The UNC dual outdoor chamber, shown schematically in Figure 1, is
constructed of 0.13 mm fluorinated ethylene propylene (FEP) Teflon film
supported by an exterior wooden A-frame, 9.14 m wide, 12.19 m long, and
6.10 m high on a plywood platform 1.22 m above grouhd. It is divided into
21
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3
two compartments each 148 m by a center Teflon vertical panel. The
interior surface is 98% Teflon and 2% aluminum and glass. The chamber
operates with natural sunlight, temperature, and humidity, and the air
source is natural rural background of very low reactivity. Instrumentation
is located in a temperature-controlled laboratory adjacent to the chamber.
Glass sampling manifolds, 3.75 cm in diameter, bring air fromxthe chamber
in to the laboratory at > 60 1-min and the excess air is returned to the
chamber. Pollutants are injected from high concentration gas tanks into
this return manifold air. Two large, 0.56 m .diameter mixing fans in
opposite corners assist in mixing the chamber; this mixing requires less
than 2 minutes.
The UNC aerosol chamber is essentially identical to the gas chamber
except that it has only one compartment and a volume of 200 m . Because
of sampling requirements, the laboratory for the aerosol chamber is
located below ground, under the chamber, and several vertical, short-
sampling manifolds are used.
The four side-by-side outdoor chambers at RTI are of a different
design. Each chamber is a cylinder, 3 m in diameter and 3.66 m high on a
plywood platform. Aluminum channel is used as an interior framework and
FEP Teflon film, heat sealed into a cylinder, is mounted around the
aluminum frame. The four chambers are placed approximately 4.5 m apart
in a clear area between two laboratory buildings. Each chamber is
equipped with an air purification system that uses chemical scrubbers to
remove water and oxides of nitrogen and a catalytic combustion system to
remove hydrocarbons including methane. This was necessary because the
ambient air at RTF contains traces of auto exhaust.
At the UNC chambers, a computer based data acquisvtion and control
system fully automates chamber and instrument operation. A PDF 11/40
computer with 56 kilobytes of memory, a 2.4 millionbyte disk system, two
terminals, digital clocks, a Hewlett Packard 5h digit digital voltmeter,
200 channel, 3-wire analogue multiplexer, and solid state controlled ac
power switches can operate chamber intakes and exhaust, fans, blowers,
injection gases, strip charts, and sampling valves. It simultaneously
22
-------
acquires data from instruments in both the gas and aerosol laboratories,
carries out calculations, stores data and prints out data in real-time in
physical units. The computer can carry out complex timing tasks necessary
to simulate the continuous injection and dilution that occurs in the real
atmosphere.
TYPES OF EXPERIMENTS IN UNC CHAMBER
There are four general types of experiments that have been performed
in the UNC chatnBer: static, slow dilution, two types of dynamic, ,and full
atmospheric simulation experiments.
Static experiments. In static experiments, all of the reactant mass
is injected into the chamber before sunrise and the system remains closed
for the duration of the run, usually until sunset. These are the simplest
type of experiment that can be performed and they test the effect of varying
initial reactants under conditions of diurnal light and temperature. In
general, NO initial conditions are the same in the two chamber sides and
/\
initial hydrocarbon (HC) concentrations are different. Two types of
hydrocarbons have generally been used, propylene in chamber testing experi-
ments, and a simulated urban mix consisting of acetylene, five paraffins,
and six olefins. An example of such an experiment is shown in Figure 2,
taken from "Outdoor Smog Chamber Studies : Effect of Hydrocarbon Reduction
on Nitrogen Dioxide" (EPA-650/3-75-011, June, 1975). This data graphically
illustrates the effect of initial HC reduction while keeping initial NO
/\
constant.
Dilution Experiments. In these experiments, the initial chemical
conditions are the same. One side of the chamber, however, is slowly
diluted (9.5% h ). Figurefs, taken from "Ozone Transport Phenomena :
Observed and Simulated" (paper no. 76-14.3 presented at Portland APCA
meeting, June 1976) illustrates the outcome in such experiments. The
diluted side makes more 03 if the dilution rate is approximately equal to
the NO to N02 conversion rate. This results in a more favorable NOp to NO
ratio earlier in the diluted run and subsequently more 0-
23
-------
Another experiment in .the aerosol chamber, using a high concentration
propylene-NO system, illustrates how difficult it may be to dilute 0Q in a
U ^
photochemically active system (Figure 4). Although the dilution rate was
50% h~ after 1215 EOT, the 03 decreases only slowly suggesting that 03
formation was approximately 50% h"1.
s
Dynamic Experiments. In dynamic experiments, the reactants are not
added all at once in the beginning of the experiment, but rather they are
added slowly over several hours (3 to 12 hours). In some experiments, the
chamber was closed (that is, semi-batch) and in others, the chamber was
simultaneously diluted while injection was occurring. These types of experi-
ments are very simple simulations of urban atmospheric dynamics. Figures
5, 6, and 7illustrate the results in ramp (semi-batch) type experiments.
Although the NO, N02, and HC profiles are dissimilar, the 03 profiles are
very similar, suggesting that the total mass added controls the final 03
concentration. Table 1 shows that this behavior holds over a wide range
of initial conditions and HC to NO ratios. The maximum 0- in dynamic
X Q
experiments is approximately 90% of the maximum 03 in static experiments.
In another type of dynamic experiment, called simulate, conditions
are as follows: a) in the static side reactants are added all at once before
sunrise, b) in the dynamic side, reactants are initially injected beginning
at 6 a.m. at a constant HC to NO ratio and at a rate such that at 9 a.m. the
y\
masses on the two sides would be identical, c) beginning at 9 a.m. until
12 noon, the chamber is diluted so as to remove 50% of the mass and injection
continues at a rate which would have doubled the injected mass by 12 noon,
d) after 12 noon, both injection and dilution ceases and the chamber becomes
a simple batch reactor. The results of such an experiment using the urban
mix are illustrated in Figures jjrjTT Although from 9 a.m. to 12 noon mass
is being added and removed, the profiles for NO, N02, and 03 are essentially
identical.
Full Atmospheric Simulations. We are currently simulating an actual
atmospheric event, Operation 33 from the Los Angeles Reactive Pollution
Program (LARPP). In LARPP, tetroons were used to "tag" a trajectory for
24
-------
an air mass and two instrumented helicopters were used to measure pollutant
concentrations at 200, 400, 600, and 800 feet above ground level along the
tetroon path. We have chosen one of these operation to simulate in the
outdoor chamber. The helicopter data was subjected to extensive analysis
and the results were used in a vertical transport model to compute vertical
flux of pollutants. An analogy between a variable-volume continuous
stirred tank reactor and the atmosphere allowed this flux to be converted
into dilution rate and pollutant injection rate for the outdoor smog
chamber that would result in very similar behavior of the chamber contents
#
as that for emissions and atmospheric dynamics in the real situation.
The mean concentrations of NO, NO^j and 0- observed in individual
helicopter patterns in the well-mixed region of the atmosphere are shown
in Figure 12. Profiles from a chamber simulation run are shown in Figure
13. It was necessary to inject the NO into the chamber as 75% NO, 25%
/\
NOpto obtain reasonable 03 formation in the chamber simulation. The
integrated injected hydrocarbon (total mass injected up to a given time)
and the effective chamber volume necessary to simulate LARPP 33 are shown
in Figures 14 and 15. It would seem that, if operated similarly to the real
atmosphere, smog chambers can reasonably duplicate atmospheric behavior.
f "
EXPERIMENTS IN THE RTI CHAMBERS
The RTI chambers have been used to simulate the effects of dilution
and transport on 03 formation. These experiments typically last three
days, begin with an urban type HC/NO system, are subjected to varying
A
degrees of dilution (beginning on the first day and lasting 24 h). An
example of such an experiment is shown in Figure 16. In this run, 95% of
the mass was removed between N0-N02 crossover (^ 9 a.m. on the first day)
and 9 a.m. on the second day. The remaining 5% of the mass was still able
to make more than 0.3 ppm of 03 on the second day and 0.25 ppm of 03 on
the third day.
Comparisons of 03 profiles for second day irradiations at three
different dilutions (100% of material remaining, 23% of material remaining,
and 5% of material remaining) are shown in Figure 17. The 03 maximum are
reduced by 53 and 40% of the no dilution case. This suggests an increased
yield of 03 percursor molecule under these conditions.
25
-------
cn
END
SIDE
BLUE
RED
(A)
(B)
....raws,. • ^>:;s??:;a-T.';.>'. •.. .;•,?...:-... *>^r-v^l(lA....,...,.,li,..-.-ii-.%^.ir;!?^l?>:r.-'"'
'1
STRUCTURE OF CHAMBERS
(C)
TOP
INTAKE/
DOOR
FLOOR PLAN OF CHAMBERS
Figure 1. Schematic of UNC outdoor smog chamber.
^INTAKE
DOOR
-SAMPLING LINES
MANIFOLD
CT>
-------
NJ
JULY 2, 197*
10 11 12 13. H .15 . 16 17
; HOURS. EOT
Figure 2. ' Profiles for dual run. Initial conditions: NOX(—) 0.507, (—) O.BlO.ppm;
N02(—) 0.100, (—) 0.102 ppm; NMHC(—) 4.00, (—) 2.29 ppmC urban hydrocarbon
mix in UNC outdoor smog chamber.
-------
03
- 0.1
' I ' I ' I ' I ' I ' I ' I ' I '
OCTOBER 7. 1971 HC MIX - NO,
Dilution starts
NO
P
P
- 0.2
0.0
15 16 17
, • HOURS. EOT
Figure, 3 Dual nm conparlno. dilution and no dilution. Initial Condition: NO. (_)-n.514,
(---) 0.512 ppffli NO, (_) O.in.6. (---} 0.111 epm; t|MHC (_) 2.3". (-,-} Z.43xppmC urba.i
tiydrocarton nix In ONC outdoor smoq chamber. Dilution rule 9.5* hr .
IS 16 17 18 19
: ' HOJRS. EOT
M|ut« 5 i Stjtlc (—) «nd »««p (-—) Injictlon Du.nl Run In VKC OuUuor 5nof Oiub2, 0.0? ffm; n-C«H|0, 0.60 pp«C;
Cjllt! O.AO ppmC. R«»p lU< (---) would HO, 0.36 ppn; n-C«ll]Q. O.tO pp»Ci CjHj. 0.40
pp»C C at 1100 hoiura If n> rutCiM occunrt.
1.00
0.90
0.80
0.70
0.60
0.50
0.10
0.30
0.20
0.10
0.00
19
Inlrtil
00
-------
.600
.500
o. •
o.
.300
.200
.100
.000
i r
1 I ' I ' I ' I ' I '
flUGUST 13. 1976 -
.600
.500
9 10 11 12 13
HOURS
15 16 17 18 19"
.300
.200
.100
.000
Figure 7 Static {—) and Ranp (—) injection dual run in UNC Outdoor Smog Chamber.
Initial Conditions at 0540 in static side (—): NO, 0.151 pom; NO., 0.072 ppm;
1.93 ppmC urban hydrocarbon mix. Ramp side (—) would achieve: NO, 0.22 ppm;
1.93 ppmC urban hydrocarbon mix at 1800 hours if no reaction occurred.
TABLE 1. Ozone Formation in Static and Ramp Injected Outdoor
Smog Chamber Experiments
Precursor
Conditions3
Date
8/16/75
8/17/75
8/18/75
8/4/76
8/5/76
8/6/76
8/12/76
8/13/76
8/24/75 '
8/30/76
^-
0.37
0.36
0.36
0.35
0.31
0.24
0.24
0.24
0.38
0.36
HC
0.98
1.00
1.00
0.97.
1.93
0.97
1.93
1.93
4.00
4.56
cmp
P
B/P
B/P
M
M
M
M
M
M
M
HC/NOX
ppmC/ppm
2.65
2.78
2.78
2.70
6.23
4.04
8.04
8.04
10.53
12.00
03 max,
static
0.68
0.28
0.18
0.05
0.24
0.17
0.72
0.49
0.57
0.74
ppm
ramp
0.48
0.25
0.16
0.05
0.32C
0.29C
0.65
0.41
0.46
0.65
ramp/static
%
71
89
89
100
133
171
90
84
81
88
a initial values for static experiments established at 0540 EOT and values that would
have existed at 1800 EOT in ramp injected experiments if no reaction occurred.
P, propylene; B/P, 60% n-butane-40% propylene by carbon; M, synthetic urban
mixture of acetylene, paraffins, and olefins.
c NO injection rate for ramped side lower than required to give final NO value
29
-------
U)
O
1.00
0.90
o.eo
E 0.70
S0.60
•
** 0.50
eS
0.20
0.10
0.00
! I ' 1 ' I ' I ' I ' I ' I ' I ' J ' I ' I '
flUOUST 30, 197S .
7 8 9 10 11 12 13 11 15 16 17 18 19
HOURS. EOT
i.OO
0.90
0.00
0.70
0.60
0.50
O.*0
0.30
0.20
0.10
0.00
Tlfurj 8 St.tic (—) and Ramp injection (0(00-0900) tilth SOX dilution (0900-11001 and
coRtluued ramp injection (0900-1200) at rate equal to wiiaa removal by dilution il no reaction
(—). Initial condition! in atatlc (—) aide: NO, 0.31 ppni NO], 0.05 ppn. Urban hydrocarbon
•in, 4.M. ppiC. An initial condition o( 0.0} ppn K02 vaa eitabllihed U rii.p (-—) (Ida.
DO and «.!« injected Jn (—) ao aa to achieve aae» condition i at 0900.
2.00
1.00
1.60
T£ 1.10
1.20
I 1.
00
" 0.80
•
g 0.60
5 o.io
o
40 0.20
o.oo
T I I I I I I I I I < I I I ' 1 ' I ' I ' I ' I ' I '
flUOUST 30, 1975 -
tx
t . I . I . I . I . I I I 11 11 I i 11 I
5 6 7 8 9 10 11 12 13 11 IS 16 17 18
{ HOURS. EOT
njur*. 1 OsoUr ndlatlon for August 30, 1975.
2.00
1.80
1.60
1.10
1.20
1.00
0.80
0.60
0.10.
0.20
0.00
1.10
1.00
0.90
0.80
0.70
°-60
O.SO
0.10
0.30
0.20
0.10
0.00
1 I ' I ' I ' I ' I ' I ' I ' | ' 1 ' | ' | ' |
~~0~0~'0""V«b ...... ,.„.». fiUCUST 30- 1975 -
•thjrluu •
Kt I t I i ( i I , I
» 1.1
9
UJ.cllon
' ••- '• •^^•™"«»»—•"»*»™—W«»ea».»j..^-..IJMW*..M,fc..Md,-e«a*—•l.^JL^.Bn,,,^,,^J.^..
5 6 7 8 S 10 U 12 13 11. 15 16 17
HOURS, EOT
Selected hydrocarbon ccvoaunde In Urban hydrocarbM ml* for Static *—*
' (—} Dual Run i, we Outdoor SMI Oiartor.
18 19
1.10
1.00
0.90
0.80
0.70
0.60
O.SO
0.40
0.30
0,20
0.10
0.00
P. 11
.' I ' I ' I ' I ' I ' I '.I ' I
flUCUST 30,
-T-p-
1975
0.00 I i If \ I i I i » i I f I i I • I . f L I . I . I . J .
S 67 8 3 10. 11 12 13 11 IS 16 1?
HOURS, EOT
(«<•*• * (elected hydrocarbon emoounda In Urban hydrocarbon ml* (or Static <—»
Inj.ctlon (—) Dual Dun In IMC Outdoor «~t Charter.
18
0.11
0.12
0.10
o.da
O.D6
0.01
0.02
o.bo
-------
.300 -
Q_
Q_
o
-£•
CC
n
O
O
r ... i . I r
.200 -
.100
.400
- .300
- .200
.100
9.0 10.0 11.0 12.0 13.0
000
PflCIFIC STflNDflRD
Ftgure: 12.:- -^earrcoTTcentrcrtTtirrs-Trf nit -Ir -ox1 de, n 1 trogen-d1 ox1 tteTrnKT ozone
helicopter patterns within the well-mixed region.
-------
to
.350 -
.300
e .250
OL.
- .200
o
.150 -
§ .100
050
000
OCTOBER 13, 1976. BLUE CHflMBER
- .050
8 9 10 11 12 13 14- 15 16 17
HOURS. PST
.000
Figure 13 Chamber Simulation of LARPP Operation 33
-------
' 8.00
7.00
UJ
6.00
5 s.oo
o
| 4.00
UJ
gs.oo
tn
z:
2.00
1.00
0.00
1 I ' I ' I ' I
1,1,1. I ,
. I ,
8.00
7.00
6.00
S.OO
1.00
3.00
2.00
1.00
5.0 6.0 7.0 8.0 9.0 10.0 11.0. 12.0 13.0 H.O
f PRCIFIC STflNDflRD TIME
Figure lH Cumulative nonmethane hydrocarbon injection for smog chamber simulation of
LARPP Operatfbn 33.
0.00
20.0
19.0
. 18.0
17.0
16.0
15.0
t I3-0
"- 12.0
2 11.0
10.0
uj 9.0
8.0
7.0
6.0
5.0
o
•si
o
3.0
2.0
1.0
0.0
1
1
I rj:
!
^ 6.0 7.0 8.0 9.0 10.0 11.0 12.0 13.0 H.O
^ PflCIFIC STANDflRD TIME
FigurelS. Cumulative dilution volume for smog chamber simulation of LARPP Operation 33.
33
-------
U)
3 6 9 12 IS 18 21 0 3 6 9 12 If 18
TIME OF OflY
Hwnl& Thr« d.y outdoor run «lth dilution. InltUI condition: HO , 1.00 pp«i HO,, O.M pp.}
X lirlun •!«. 7.02 ppmC In HI outdoor M«g «M»btr nu«l>tr 1. Ollutle* >^<* i« OH4, 7/M
lad contlnuod for 24 hour* *t t raU of 121 hi-1.
0.00
1.00
0.90
0.80
0.70
0.60
I O.SO
a
0.30
0.20
0.10
0.00
1 I ' I ' I ' I ' I ' I ' I ' I ' I ' I ' I '
7/29, 8/09; 8/13, 1975.
I
I
I
00 02 04 06 08
10 -12 14
HOURS. EOT
1.00
0.90
0.80
0.70
0.60 !
16 IB 20 22 24
O.SO '
0.40 '
0.30 .
0.20
0.10
0.00
dty oiont pnfllti for thrtt 4(1iillOM it I tut flnt <*/ loltltl
' tofldUlon (HO,, 1.00 tf»\ Mj, O.tl PP*I wlM ill, 7.02 pp»C) III KTI
outioor ckwDiri.
I
-------
The Concept of Prevention of Photochemical Oxidants — with
Reference to Results of Smog Chamber Experiments
Japanese Delegation
1. On Results of Smog Chamber Experiments; Japanese and
s
Overseas
1.1 Air Pollution by Photochemical Reaction
Photochemical air pollution is defined as the mixture
of hydrocarbons and nitrogen oxides in the atmosphere subjected
to the radiation of sun light (especially the ultraviolet
component of sunlight). The product of this mixture is the
formation of new compounds such as photochemical oxidants.
The reaction mechanism of the photochemical air pollution in
the environmental atmosphere is very complicated, and the
characteristics of the reaction process can be summarized in
the results of previous smog chamber experiments as shown in
the following.
(a) Rapid oxidation of nitric oxide to nitrogen dioxide.
(b) Decrease of initial hydrocarbons.
(c) Increase of aldehydes.
(d) Increased concentration of ozone.
(e) Decrease of nitrogen dioxide.
(f) Increase of nitrates.
(g) Increase of aerosol.
However the coexisted substances such as sulfur dioxide,
etc. participate in the photochemical reaction in the environ-
mental atmosphere in addition to the hydrocarbons and the
35
-------
nitrogen oxides, thus the process covering the whole reaction
system is very complicated.
In order to qualitatively, as well as quantitatively,
explain the photochemical reactions of non methan hydrocarbons
s
and nitrogen oxide complexes in environmental atmospheres,
studies using the following methods have been actively
carried out to date:
a) 1. a method to measure hourly changes of reactants
and generated products by irradiating mixtures of nonmethane
hydrocarbons and nitrogen oxides with artificial light (or
sunlight) in a smog chamber.
a) 2. a method similar to the above a)l, in which
environmental air samples will be collected in a smog chamber.
Since the Environment Agency is conducting experiments with
a smog chamber loaded in a car, these are called the mobile
smog chamber experiments.)
b) a method whereby the photochemical reactions will
be modelled and the calculation of numerical values will be
made according to a series of the modelled reaction formula,
thereby quantitatively estimating the reaction process.
c) Not only the concentration and the composition of
reactants as well as the intensity of ultraviolet ray change
-2-
36
-------
in terms of time and space, but also such conditions as cli-
mate and geography are complicatedly intermixed, which will
inevitably contribute to the generation of photochemical
s
oxidants. This is an analysis method by using the environ-
mental measurement data which express comprehensively such
phenomenon.
1.2 On Different Smog Chamber Experiments
A detailed review of smog chamber experiments on photo-
chemical air pollution reveals that different conditions are
applied for different experiments. They can be categorized
as follows:
1) Samples
a) NMHC and/or NO , independent or mixed
j£
b) Diluted automotive exhaust gas
c) Ambient air
2) Irradiation: type and intensity
a) Artificial light
b) Natural light
3) Materials and size of the smog chamber
•«
4) Methods of measurement and analysis of reactants and
products.
5} Conditions of experimentation: initial concentration
of reactants; temperature; humidity; agitation (or no agita-
tion) ; duration of experiment.
- 3 -
37 .
-------
6) Replenishment (or no replenishment) of air samples for
measurement and analysis consumed in the chamber.
A straightforward comparison of the results of experi-
/
ments without due consideration to above-mentioned variations
in their conditions would be meaningless. This is a point
that calls for attention in utilizing any experimental data.
1.3 Outline of the Results of Photochemical Reaction Experi-
ments by a Smog Chamber
Ths smog chamber experiments conducted both in U.S.A.
AND Japan have clarified the following points concerning
the generation of ozone or photochemical oxidants.
a) The rate with which ozone will be formed is accele-
rated according to the increase in the initial concentration
of nonmethane hydrocarbons and subsequently decelerated when
the initial concentration of nitrogen oxides is steadily
fixed and the composition qf nonmethane hydrocarbons is
common. (Fig. 1)
— 4 —
38
-------
30.0x10
-3
C
.3
.8
GJ
I
o
0)
10.0
3.0 -
1.0
0.3
0.1
The initial concentration
NO = 0.5 ppin
\
0.1 0.3 1.0 3.0 10.0 30.0
C3Hg/NOx (ppm/ppm)
Fig. 1 The ozone (03) formation rate when the
initial concentration of nonmethane
hydrocarbons is steadily fixed and the
concentration of propylene is altered
(source: • Yanagihara , 1975)
Note: Figures 1-3 show the results of experiments using
propylene as one example, but similar relations have
been elucidated by experiments using hydrocarbons
other than propylene or automotive exhaust gas.
b) The higher the initial concentration or nitrogen
oxides, the higher the maximum concentration of ozone when
nonmethane hydrocarbon concentrations'a»e nigh and the
reactivity is .sufficiently large. (Fig. 2)
- 5 -
-------
X
o
B)
*»
c
•s
•H
X
o
H
O
|
I
S
£
0.7 .
0.6
0.5
a. 4
0.3
0.2
0.1
The initial concentration of
4 ppm C
,0 123 45 6
Irradiation time (h)
Fig. 2 The formation of photochemical oxidants
when the initial concentration of propylene
is steadily fixed and the concentration of
NOX is altered (source : Yanagihara* ,
1971)
7) The maximum concentration of ozone is affected by the
initial ccmcentration ratio of nonmethane hvdrocarbons—to
nitroaen oxides when the composition of nonmethane hydro-
carbons is equal. Fig. 3 shows the relations between the
maximum concentration of ozone and the initial concentrations
of nonmethane hydrocarbons and nitrogen oxides. In this
connection, it- is known that the formation of osone will be
also affected by the ^intensity of liqftt irradiation, the
irradiation time, temperature, hymidity, sulfur dioxide, etc.
As is clearly shown by Fig. 3, the maximum concentration of
ozone will become higher when the concentration ratio of
— o —
40
-------
nonmethane hydrocarbons and nitrogen oxides remains within a
certain range.
s
I
-------
•H
O
C
O ~
+J g
C
Sa
8E
<">
i °
E fl)
*ri C
x o
Id t4
6 O
0
*
0.6
0.5
0.4
0.3
0.2
o.i
0
s
s
s
s'
/
/
/
•^
J
V
^r
^
i . i
5 10
The initial hydrocarbon concentrations (ppm C).
Fig. 4 The maximum concentration of ozone arising
from automotive exhaust gas when the ratio
of hydrocarbons and nitrogen oxides is
almost steadily fixed
(HC/NOX = 7-10; ppmC/ppm)
(source: Yanagihara , 1975)
Also it is reported from another experiment using auto-
motive exhaust gas that, when the initial concentration ratio
of hydrocarbons and nitrogen oxides is less than 2.5—hydro-
carbons (ppmC)/nitric oxides (ppm)—,. the formation of ozone
is extremely slow and the ozone concentration will never
exceed 0.1 ppm, regardless of the initial concentrations of
hydrocarbons and nitrogen oxides, even after 5-6 hours of
irradiation of light almost equal to sun light.
In Japan Yanagihara has concluded that protochemical
oxidants will not exceed 0.1 ppm if in particular nonmethane
hydrocarbons is below 0.4-0.5 ppmC.
In this manner, numerous results of the smog chamber
— 8 —
42 "
-------
experiments have been reported from the past. These results
are generally highly reliable: for example, the above
experiment using automotive exhaust gas shown in' Fig. 5 has
been made under such conditions that hydrocarbons and nitrogen
oxides were fixed at more than 0.1 ppmC and 0.08 ppm respec-
tively. However, since a smog chamber experiment under the
condition of low concentrations will face many difficulties
such as the loss of reactants and substanced produced within
a chamber, and other significant effects which cannot be
neglected, reliable results have not been reported so far
under such conditions that the initial concentrations of
hydrocarbons and nitrogen oxides are fixed at less than 0.1
ppmC and 0.05 ppm respectively.
1.3 Outline of the Results of Photochemical Reaction Experi-
ments Made by a Mobile Smog Chamber
The Environment Agency has been yearly carrying out
irradiation experiments with a mobile smog chamber taking
environmental atmospheres with different composition of
reactant concentrations as air samples since the summer of
1972. Figs. 6 and 7 show the results of these experiments.
These experiments may not be completely reliable beceause
they include somewhat inaccurate measurements of nonmethane
hydrocarbons and nitrogen oxides and very few attempts have
been made to carry out adequate measurements to cover the
- 9 -
43
-------
total scope of nonmethane hydrocarbon as well as nitric
oxide concentrations. Yet, very roughly speaking, we may
safely draw the following conclusions f
• a) There is a tendency that as the concentration of
nonmethane hydrocarbons will become higher, the maximum
concentration of ozone will increase?
b) The maximum concentration of ozone will not exceed
0.1 ppm, with one exception, when nonmethane hydrocarbon
concentrations are approximately less than 0.4 ppmC or the
concentration of nitric oxides is approximately less than
0.04 ppm;
c) It is difficult to show an equal concentration line
for the maximum concentration of ozone as the function of
nonmethane hydrocarbons and nitric oxides.
- 10 -
44
-------
2. Problems
Laboratory studies such as smog-chamber experiments and
numerical computations using photochemical reaction models
provide us with useful findings on the mechanism'of photo-
chemical reaction and relationships between reactants and
products. Various problems arise, however, when attempts
are made to draw on these results to establish measures
against oxidant formation on the assumption that these
results represent actual atmospheric phenomena.
There are, in the first place, problems in the smog-
chamber experiments as such. Normally reactants are not
replenished after ultra-violet irradiation in smog-chamber
experiments. In other words, the most important substances
in oxidant formation such as NOX and NMHC are only consumed,
and results can never be identified with phenomena in the
actual atmosphere. The use of numerical simulation may
enable the establishment of a reaction system which takes
into account reactions at very low concentrations, replenish-
ment and diffusion of substances, etc. This is a task that
we must come to grips with in the future.
Secondly there are problems of fluctuation of NOX and
NMHC concentrations in the ambient atmosphere. In the real
ambient atmosphere NOX and NMHC fluctuate greatly over time
and between places. Therefore even if certain Ox or 03
isopleth were obtained in the smog chamber, in actual application
an isopleth at maximum oxidant concentration must be considered
- 11 -
45
-------
taking into account the fluctuation of its initial value.
In the third place, oxidants or ozones are only one
of several indices of photochemical air pollution, and
s
the reduction of these alone will not prevent photochemical
air pollution. Health effects of photochemical air pollution
are in the main irritation of the mucous membranes of the
eye, throat, etc. According to a study by Romanovski,
the irritation of the eye corresponds relatively well to
the HC concentration. It is deemed that such irritation
is caused by the occurrence of peroxy radical of HC as an
intermediate of the oxidant formation process, or by the
formation of aldehydes and organic nitrates such PAN and
PBzN. In addition, inorganic nitrates are formed from oxides
of nitrogen by photooxidation. It is often pointed out
that all these products cause health effects such as irri-
tation of mucous membranes. Consideration of nothing but
oxidants therefore would be inadequate in countering photo-
chemical air pollution.
- 12 -
46
-------
3. Approach to Ox Control on the Basis of Present
Scientific Findings
We would like to consider ways and means to achieve
the -environmental standard for oxidants by drawing on the
results of smog-chamber experiments and NOx and NMHC con-
centration measurements in early morning with due attention
to the abovementioned aspects. Not many measurements of
NMHC have been conducted in Japan so far.
According to a measurement of air pollution in the
urban center of Tokyo, HC, NOX and HC/NOX fall within the
following ranges of concentration as shown in Table 1.
Table 1. Air Pollutions: Early Morning
Concentrations in the center of
Tokyo
1974
June'-Sept.
1375
May'- Sept.
Max
Min
Mean
S.D.
Max
Min
Mean
S.D.
NMHC *
1.30 ppmc
0.25
0.667
0.191
1.40
0.10
-
-
NOX *
0.15 ppm
0.03
0.073
0.044
0.12
0.01
-
-
NMHC/NOx
21
2
7
-
35
2
8
-
6-9 a.m. average a concentrations.
- 13 -
47
-------
Oxides of nitrogen are major reactants along with
NMHC in the formation of photochemical oxidants, and it is
said furthermore that the amount of Ox produced is greatly
affected by the ratio of centrations of these two precursors.
In other words, ozone, the major component of Ox, is
scavenged by NMHC when NMHC is in excess, and by NO when
NOx is rich. The role of hydrocarbons is to promote
oxidation of NO into N02- Ozone is formed when N02 dissociates
by photolysis into NO, and both HC and NO become scavengers
of 03. Isopleths are drawn Figs 5~6) when expressing the
relationships of the concentrations of these three.
The concentration of air pollution in Japan is sub-
stantially lower than that in California U:S.A., and the
estimate that the HC/NOX ratio is unfavorable for Ox formation
cannot be denied. Yet the theory that Ox concentration
should be reduced by manipulating the ratio cannot be applied
to Japan in reality.
Looking at the present situation in Japan, reduction of
either precursor will lower Ox concentration.
In Japan where NOX reduction has been implemented on
N02 as a precursor of Ox formation and for its health effects,
a realistic approach would be to reduce hydrocarbons simul-
taneously.
- 14 -
48
-------
x: experimental figures
( 03 j ppilm )
Fig. 5 Ox isopleths (by Demitriades)
- 15 -
49
-------
NOx
<**«>
•30
02S
020
US
•JO
005
.Ji*
7.5
. C&O, 3-2.347CNOJ
su
.200
1U
OJSp
• 22
•"CHC34"*
8! Air pollu
at" present
;ion concentration
( 6:ooa«m. —
Jtm.e -Sept* )
184
Fig. 6 Results of mobile smog-chamber
experiments
- 16 -
. 50
-------
Nitrogen Oxides Control Measures in Japan
(Environment Agency)
_ _ . , .. Japanese Delegation
1. Introduction
Nitrogen oxides are one of the pollutants that require the
greatest attention because they not only have a deleterious effect
on human health but also are one of the precursors of photochemical
air pollution — so much so that the nitrogen oxides control measures
have been progressively replacing in importance the sulphur oxides
control measures.
Since early in 1965, the rapid progress of air pollution by
nitrogen oxides has been attracting increasing attention. Since the
sensational "photochemical smog incident" that occurred in July 1970
at the Eissho Senior High School in Tokyo where many students com-
plained of photochemical smog symptoms, there has been rapidly
increasing social interest in nitrogen oxides, along with hydro-
carbons, as the precursors of photochemical smog.
Nitrogen oxides are air pollutants that are produced inevitably
in the course of combustion at high temperatures and their chief
sources are factories and motor vehicles but there are many and
diverse smaller sources that cannot be ignored such, as domestic
heating. The contamination of nitrogen oxides in ambient air is
closely related to the expansion of economic activities and the
improvement of our standards of living=
The progress of regional development, increased income and
mortorization proceeding from the rapid economic growth achieved
1
51
-------
since the 1960's have brought about such rises in the concentra-
tions of nitrogen oxides in ambient air as shown in Fig. 1.
Pig. 1 Change in annual mean HC>2 concentration
(Average of 6 monitoring stations) '
ppm
0.05 -
0.04
0.03
0.02
0.01
FY1968 '69 '70 '71 '72 '73 '74
0.022 0.023 0.028 0.026 0.029 0.034 0.033 ppm
Uote: Saltzman coefficient : 0.72
Fig. 1 shows the change in nitrogen dioxide concentration,
measured continuously since 1968 at six state-operated air pollution
monitoring stations.
Fig* 1 shows that this average leveled off from FY1973 to
FY 1974* However, the yearly average increased by 0.011 ppm during
the six years from FT 1969 to FY1974. (Japan's GHP increased from
¥63,000,000 million to ¥136,000,000 million during the same period.)
By way of studying the geographical distribution of nitrogen
oxides pollution in Japan, the N02 and NOx distributions in FT1974
2
52
-------
in the southern part of the Kanto Region where Japan's industrial
and administrative nerve centers are concentrated were as shown in
Figs. 2 and 3- The air pollution by these pollutants is spreading
from the industrial zones along the Bay of Tokyo to- the widespread
inland areas.
Taking a look at the annual mean N0£ concentration at 245
monitoring stations which measured the concentration continuously
during the two years' period of FI1973 and PT1974, it is seen that
the N02 concentration lowered at 28$ of the monitoring stations,
levelled off at 67$ and rose at 5$ during the two years, suggesting
the gorwing signs of improvement of air quality due to the increasing
energy saving because of economic recession and the effects of the
anti-pollution regulations that have been enforced since 1973•
2. Ambient air quality standards for Nitrogen dioxide
(l) Nitrogen oxides not only reach easily into the depth of lungs
by respiration and produce by itself harmful effects — even
more harmful than sulphur oxides — in lungs and other organs,
but synergistic effects with sulphur oxides and suspended
particulate matter are observed. They also are precursors of
photochemical oxidants. Particularly, in the urban and
industrial areas where a large population and industrial plants
are heavily concentrated, establishment of ambient air quality
standards that serve as a basis for evaluating the level of
ambient air concentrations and implementing emission control
3
53
-------
Fig. 2
Yearly average N(>2 value
distribution
ppm
- 1974 -
• Monitoring Station
-------
U1
* > pr*^
Yearly average (NO +
value distribution
- 1974
ppm
0
i L.
• Monitoring Station
-------
measures was an urgent necessity in order to protect human
health, in such areas.
Under such circumstances, the ambient air quality standard
for nitrogen dioxide were established in May, '1973- The Experts
Committee for the ambient air quality standards for nitrogen
oxides under the Central Council for the Control of Environ-
mental Pollution stressed in its report the further necessity
of establishing an ambient air quality standard for nitrogen
monoxide along with that of nitrogen dioxide. The standard
provides that "daily average value of hourly values shall not
exceed 0.02 ppm." The period for the attainment of the standard
was also decided as follows: unless otherwide required, the
standard shall be met as soon as possible within five years,
although in areas where the industrial activities and the
population are extremely concentrated with consequent high
concentrations of nitrogen dioxide and the attainment of the
newly established standard is difficult because of the lack of
effective control technique available, the standard shall be
met within eight years.
The ambient air quality standards for nitrogen dioxide
was not decided on account of its relationship to photochemical
oxidsnts but was established on account of the toxic effects
of nitrogen dioxide itself, taking into consideration the
combined effects of sulfur dioxide and dust.
6
56
-------
(2) The ambient air quality standards for nitrogen dioxide were
established on the basis of the results of medical examinations
conducted in Japan and abroad before June 1972. Unlike in the
case of sulphur oxides, the epidemiologic al data concerning
the long-lasting effects of serious nitrogen dioxide pollution
on human health had not been sufficiently accumulated and the
available data were limited. However, the data obtained by
experiments with animals had been fairly well accumulated in
Japan and other countries. On the other hand the measurements
of air pollution by nitorgen dioxide were rather new compared
with the measurements of sulphur oxides both in Japan and abroad
and the methods of measurement and analysis were liable to errors
to some extent at relatively low levels of nitrogen dioxide in
the air.
The air pollution by nitrogen oxides tended to gradually
increase year after year to the extent that it could not be
ignored from the viewpoint of its effects on human health and
the ambient air quality standards for nitrogen dioxide were
established in May 1973.
The scientific basis on which the ambient air quality
standards for nitrogen dioxide has been much discussed since
last year, because nitrogen oxides have a higher degree of
indeterminancy than sulphur oxides and yet the nitrogen dioxide
control measures to be taken are expected to have serious social
and economic effects. Unlike in the case of sulphur oxides,
7
57
-------
where control measures were taken only after many serious
cases of damage caused to human health such as the abnormally
high incidence of respiratory disease in the vicinity of the
large industrial complex in Yokkaichi and the very serious cases
of smog hazards in London, the air quality standards for nitrogen
dioxide have been set up as a target for the long range admini-
strative efforts to be achieved and maintained by long-range
administrative efforts to protect human health by preventing
the serious danger of air pollution by nitrogen oxides.
The Basic Law for Pollution Control provides that the
environmental standards should be constantly subjected to proper
scientific judgement and necessary amendment. However, as far
as the existing ambient air quality standards for nitrogen
dioxide is concerned, there have hitherto been obtained no hew
scientific findings sufficient to make any amendments to the
standards.
The Environmental Agency is presently makirg a comprehensive
analysis of the data obtained from the five-year survey on
health damage caused complex air pollution and is tabulating
the results of the survey on the health hazards of air pollution
along Rational Highway No. 43 and Tokyo-Bagoya Expressway.
A conference of experts on the criteria for the measurement of
nitrogen dioxide air pollution and its effects is now held under
the sponsorship of the World Health Organization (WHO) in Tokyo
during later in August 23 to September 4-
8
58
-------
The Environmental Agency is planning to reappraise the existing
air quality standards for nitrogen dioxide on the basis of all
such findings.
As for the social and economic effects caused by the
environmental pollution control policy, the Organization for
economic Cooperation and Development (OECD) is planning to
undertake the Review of the Environmental Policy of Japan in
Tokyo in the autumn of 1976 and thus obtained results will also
be of great value for us in carrying on our nitrogen dioxide
air pollution control measures in the future.
The ambient air quality standards of Japan are sometimes
discussed in comparison with those in other countries. All those
countries use the same term "ambient air quality standards" but
their statutory character, method of application, the proceeds
and scientific basis for such standards and method of evaluation
vary from country to country and therefore it would be not
appropriate to compare the standards of different countries
simply by using the standard values employed in those countries.
9
59
-------
3. Nitrogen oxides control measures
Remarkable technical advances have been made in the control of
nitrogen oxides contents in motor vehicle exhaust emissions partly
due to the promulgation of the ambient air quality standards for
nitrogen dioxide in May 1973- All the automobile manufacturers are
making vigorous efforts to achieve the initial target value of
0.25 g/km. (explained in this chapter)
Strenuous efforts are also being made for the development of tech-
niques for controlling the emission of nitrogen oxides from stationary
sources with a view to achieving the ambient air quality standards.
Speaking about denitrating technology, it has been made technically
possible if the emission gases are clean containing no sulphur oxides
and no dust or only in very small quantities, and it is highly probable
that the dirty exhaust gases which contain sulphur oxides and dust
will be controlled effectively within one or two years to come.
Such are the results of the efforts so strenuous as unparalleled
anywhere else in the world and the incentive effects of the very
strict ambient air quality standards on technological developments.
It is necessary for the nitrogen oxides emission control
measures to be carried on steadily on the basis of such technological
advances achieved in this field. It is also evident that the programs
for achieving the standards must be put into practice, taking into
consideration the social and economic effects of the enforcement of
such control measures.
It may be said that the most important task left for use to
10
60
-------
tackle in the future is to set the nitrogen oxides control measures
oriented to the prevention of health hazards on the right and solid
track, humbly reflecting on the fact that the anti-pollution
measures were not taken quickly enough to cope with the actual
situation in many cases in the past.
(l) Measures presently in force for the control of nitrogen oxides
emissions
l) Measures for the control of stationary sources
¥ith a view to attaining and maintaining the ambient air
quality standard for nitrogen dioxide, the emission standards
for nitrogen dioxide were established in August 1973 pursuant
to the Mr Pollution Control Law and were revised in December
1975.
The revised emission standards are applicable to about
3,000 nitrogen oxides-emitting installations, thereby to control
about 60/£ of the nitrogen oxides emitted by all sooth and smoke
emitting installations. As a result of these standards the
total nitrogen oxides emissions are estimated to be reduced
by about 25$.
Nitrogen oxides are generated by a variety of facilities
ranging from boilers and various kinds of manufacturing furnaces
to nitric acid manufacturing facilities and of facilities with
varying scales. Initially, priorities were given to controlling
the operation of those facilities which generated large
quantities of nitrogen oxides or in heavy concentrations.
11
-------
Under this approach, emission control was directed toward
improving combustion of fuels by applying technologies designed
to reduce the formation of nitrogen oxides available in 1975
(see Table 3). Kinds of facilities which are subject to control
at present include boilers, oil heating furnaces, metal heating
furnaces, nitric acid manufacturing facilities and coke ovens.
In terms of scales, onjy those boilers, metal heating furnaces
and oil heating furnaces having a capacity of 10,000 Kin /h or
more and those cement kilns and coke ovens which are newly
installed and have a capacity of 100,000 Nm /h or more are
subject to control, while all nitric acid manufacturing facili-
ties are subject to control regardless of their scales.
Table 3 Emission standards relating to nitrogen oxides
Facilities
Description
Boiler
(1) Gas
(2) Solid fuel
(3) of which low
grade coals
Scale
(Km5/h)
100,000
or more
40,000 -
100,000
10,000 -
40,000
10,000
or more
10,000
or more
12
62
Standard
Newly
installed
facilities
(ppm)
100
130
130
480
values for
Existing
facilities
130
130
150
600
750
•
-------
Table 3 : (cont'd)
Facilities
Description
(4) Liquid fuel
(.5) of which crude
tar
Metal heating
furnaces
Oil heating
furnaces
Cement kilns
Coke ovens
Nitric acid manu-
facturing facilities
Scale
(Mm3/h)
100,000 or
more
40,000 -
100,000
10,000 -
40,000
10,000 or
more
100,000 or
more
40,000 -
100,000
10,000 -
40,000
40,000 or
more
10,000 -
40,000
100,000 or
more
100,000 or
more
all facilities
Standard
Newly
installed
facilities
(ppm)
150
100
150 (2)
150 (2)
100
150
250
200
200
values for
Existing
facilities
230
190 (I)
280
220 ^
220 ^2'
200
210 ^
180 ^'
—
-
200
(Note) (l) excludes those equipped with stack-gas desulphurization
equipment.
(2) excludes heating furances used for the manufacture of
forge-welded steel pipes.
(3) excludes cracking furnaces used for the manufacture of
ethylene, independent super-heating furnaces used for the
manufacture of ethylene, reforming furnaces used for the
manufacture of methanol and reforming furnaces used for
the manufacture of ammonia.
13
63
-------
These emission standards are immediately applicable to
newly installed facilities, while they will become applicable
in two years to the existing boilers and heating furnaces and
s
in three years (the time needed to install high-performance
denitrification equipment) to existing nitric acid manufacturing
facilities.
However, the emission standards presently in force are
applicable to limited scales and kinds of facilities. Further-
more, the values of their standards, are inadequate to attain
the prescribed ambient air quality standards. Therefore, their
coverage must be expanded gradually and their control values
strengthened. At present hearings are being held to gather
information on the development of nitrogen oxides control
techniques from manufacturers and users for the purpose of
enforcing the third regulation of nitrogen oxide emissions.
Such control of nitrogen oxides emission may be useful in
reducing the overall national average of nitrogen dioxide
concentration but it alone is not adequate to effectively
reduce the concentration of nitrogen dioxide to the level of
its quality standards in individual localities. To remedy
such shortcomings, the government decided to introduce the
system of total mass emission control pursuant to the Mr
Pollution Control Law and it is presently conducting researches
and studies on the air pollution forecasting method and others.
Measures designed to help the operators of these facilities
14
64
-------
emitting nitrogen oxides were primarily concerned with.
improving the combustion techniques applied in boilers and
heating furnaces, such as the adoption of new burner with
low NOx formation, low-oxygen operation, two-stage combustion
system and exhaust gas recycling system. In the future,
however, not only advanced combustion techniques but also
stack-gas denitrification technologies will have to be
developed as a means of effective reduction on the one hand,
together with the measures for switch-over of fuels to gas or
distilled oil on the other.
At this point of time, technology for stack-gas denitri-
fication is feasible provided that the stacksmoke does not
contain sulphur oxides and dust (commonly referred to as
"clean exhaust gas")» and technologies based on large-capacity
equipment for denitrificating "dirty" exhaust gas have reached
a demonstration stage. The next question will be a rational
combination of these measures to bring about the maximum
reduction of nitrogen oxides from stacksmoke.
As a rule, the concentrations of nitrogen oxides in
stacksmoke must be measured once every two months (or twice
a year in the case of facilities having the capacity of
•2
emitting exhaust gas less than 40,000 Nm /h) in accordance
with PDS method, and the competent officials of prefectural
governments are .empowered to enter the premises of nitrogen
oxides emitting facilities for inspection, issue an order for
improvement and/or impose penalties for violations.
15
65
-------
2) Measures for the control of mobiles sources
i) Control of passenger-car exhaust emissions
In Japan the control on the automobile exhaust emissions
was first enforced to cover the new models produced in and
after September 1966 in order to reduce the emission of carbon
monoxide. In addition to the controls applied hitherto, new
permissible limits on the emission of nitrogen oxides (reduced
by about 3<$) were established in December 1972 for enforcement
in and after PY1973 to the ordinary small motor vehicles and
light motor vehicles which run on gasolene or liquified petroleum
gas.
As a rule, these permissible limits are based on the mass
of pollutants emitted. This is a system designed to regulate
the mass of pollutants emitted per one kilometer driven by each
vehicle as measured by methods under ten mode driving cycle
developed on the basis of the findings obtained from analysis
of the way motor vehicles are operated in Japanese cities.
As a measure to cope with the frequent occurrence of photo-
chemical smog, models produced to FY1973 were mandated in Hay
1973 to install an exhaust gas reducing device designed to
curtail the emission of nitrogen oxides and hydrocarbons.
In October 1972 the Central Council for Control of Environmental
Pollution submitted its interim report under the title of
"Methods for long-range setting of Permissible Automotive Exhaust
limits" with the result that the average emission value of
16
66
-------
0.25 g/kg was established for the target control value to be
achieved at PI1976. In January 1974, were established the
permissible limits of the various pollutants emitted from
passenger-cars for enforcement on models produced in and after
April 1975, which were designed to reduce the average emission
less than 1.2 g/km for nitrogen oxides.
The control standards enforceable in and after 1976 were
announced in February 1975, taking into consideration the state
of technological development for reducing nitrogen oxides.
As shown in Table 4, the 1976 control standards have the
permissible limits of nitrogen oxides lower than those given
by the 1975 control standards. Under the 1976 control standards,
the average emission quantity is set at 0.6 g/km for passenger-
cars of an equivalent inertia! weight (the vehicular weight plus
110kg as the weight of two persons) of 1,000 kg of less and
0.85 g/km for those of an inertia! weight exceeding 1,000kg.
These standards are applicable to new models in and after
April 1976, to the models now in production in and after March
1977, and to the imported cars in and after March 1978.
The intial target value (0.25 g/km in average emission
quantity) is required to be attained in FTL978.
¥ith regard to the development of nitrogen oxides emission
reducing technology, the engine modification system, thermal
reactor system, oxidation catalytic system, prechamber stratified-
charge engine system, and rotary engine system have been put to
17
67
-------
Table 2 1975-76 Automotive Exhaust Gas Control Standards
03
oo
Type of vehicle Measuring
method
Standard-size
cars, compact
cars, light
cars (passen-
ger-cars with
a 10-seat
capacity or
less), gaso-
<» line- or LPG-
o fueld
Q
j*
*$
Cars of equi- ,_ ,
T j. • j.. i 10 modes
valent inertial
weight not
Cars with exceeding 1,000 n modes
engine other kg (excluding
than two-cycle light cars
engine equipped with a
4-cycle engine)
Cars of equiva- 10 modes
lent inertial
weight exceed-
ing 1,000kg 11 modes
(including light
cars equipped a
4-cycle engine)
Light cars with a 2-cycle 10 modes
angina
11 modes
Permissible limit
1976 regulation
CO
2.7
(2.1)
85
(60)
2.7
(2.1)
85
(60)
2.7
(2.1)
85
(60)
HC
0.39
(0.25)
9-5
(7.0)
0.39
(0.25)
9-5
(7.0)
5.6
(4,5)
33
(25)
NOx
0.84
(0.6)
8.0
(6.0)
1.2
(0.85)
9.0
(7.0)
0.5
(0.3)
'4.0
(2.5)
1975 regulati
CO
2.7
(2.1)
85
(60)
2.7
(2.1)
85
(60)
2.7
(2.1)
85
(60)
HC
0.39
(0.25)
9.5
(7.0)
0.39
(0.25)
9.5
(7.0)
5-6
(4.5)
33
(25)
(
(9-
1.
(1.
11
(9.
0.
(o.
4-
(2.
-------
cr>
ID
Type of vehicle
Measuring
Permissible limit
method 1976 regulation '
•3
Tf
O
a
1
K
Standard-size
cars, compact Cars other than light cars
cars, light with a 2-cycle engine
cars (buses
with a 11-seat
capacity or —
more, total
vehicular Light cars with a 2-cycle
weight not engine
exceeding 2,500
kg; trucks of
vehicular
weight not
exceeding
2,500 kg),
gasoline- or
LPG-fueld
CO
10 modes 17
(13)
11 modes 130
(100)
10 modes 17
(13)
11 modes 1JO
(100)
HC
2.7
(2.1)
17
(13)
15
(12)
70
(50)
NOx
2.3
(1.8)
20
(15)
0.5
(O.J)
4.0
(2.5)
1975 regulation
CO
17
(13)
130
(100)
17
(13)
130
(100)
HC
2.7
(2.1)
17
(13)
15
(12)
70
(50)
NO:
2.3
(i.s;
. 20
(15)
0.5
(0.3)
4.0
(2.5)
(Note) 1. The units used in making measurements were g/kg for the 10-mode measurement and a/test for
the 11-mode measurement.
2. Figures in brackets indicate the average control values.
-------
Fig. 4 Effects of Automotive exhaust gas emission control
(passenger-cars)
i Prior to Apr. 1973
100^ j (no regulation)
* 1975 (PEL973 regulation)
Apr- 1975 (FY1975 regulation)
Apr. 1976 (FY1976 regulation)
Motor vehicles of equivalent inertia!
weight exceeding one ton
Motor vehicles of equivalent inertia!
weight not exceeding one ton
(Note) Equivalent inertia! weight = Vehicular weight + Weight
of two persons
practical use to meet the 1976 regulation requirements.
Following the 1976 regulation, the Japanese automotive manufac-
tures are now making research and development efforts to attain
the initial target value of average emission quality of 0.25 g/km
by FY1978.
Environment Agency has set up the "Group for the Study of
Motor Vehicle Nitrogen Oxides Emission Control Technology" formed
with four experts to make assessment of the progress now being
made in technological developments by the automotive manufacturers.
This Group has so far published its reports twice, in December
1975 and in May 1976. In August 1976 the Group had the final
hearings from Japanese and foreign manufacturers to cope with
no
70
-------
the FT1978 regulation scheduled to be established in the
autumn of 1976.
The Japanese automotive manufacturers seem to have passed
through the trial production stage and entered the mass trial
production stage by now, suggesting good prospects for the
initial target value to be attained successfully.
ii) Control of truck and diesel-engine vehicle exhaust emissions
Since July 1972, the black smoke emitted by new diesel
engine-driven vehicles has been subject to control. In view
of the growing contribution of the exhaust gases from diesel-
engine vehicles to air pollution, the permissible limits on such
exhaust gases, which were established with special emphasis
on nitrogen oxides, have been in force since September 1974-
The measurements were made on the basis of the six-mode
driving conditions for application to diesel-engine vehicles and
the permissible limits on nitrogen oxides are set at 590ppm
(l,000ppm for the direct injection type of diesel engines).
By virture of the enforcement of the regulation, the quantity of
nitrogen oxides emitted by diesel-engine vehicles has been
reduced 20$ as compared with those which were produced before
the enforcement of the regulation.
The exhaust emission control on gasoline- or liquefied
petroleum gas-fueld heavy trucks and buses has been enforced
since FY.1973. The measurements were made on the basis of the
six-mode driving conditions and the permissible limits on
21
71
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nitrogen oxides were 2,200ppia both for gasoline-fueld vehicles
and for LPG-fueld vehicles.
Exhaust emission control standards similar to those for
passenger-cars had "been applied to light-duty trucks and buses
until PY1974 and the standards were tightened in FT1975 to
reduce the nitrogen oxide content in the exhaust missions by
lift. The exhaust emission control standards presently enforced
on trucks and diesel-engine vehicles are slightly less strict
than those for passenger-cars. However, their contribution to
air pollution is too great to be overlooked and a technical study
is now under way about the advisability of further tightening
the exhaust emission control on these types of motor vehicles.
iii) Effects of control of motor vehicle exhaust emissions on air
pollution
As seen from Table 3 showing the measurements made at
state-operated automotive exhaust emission monitoring stations
in Tokyo, the levels of air pollutants emitted by automotive
exhaust gas have been lowering steadily. At the Kasumigaseki
monitoring station, for example, the concentrations of nitrogen
oxides lowered from 14.2pphm in 1970 to 8.2pphm in 1975-
On the other hand, the vehicular traffic volume only slightly
lowered from 1,198 vehicles per hour to 1,074 vehicles per hour,
practically remaining on the same level, during the corresponding
period of five years. From this finding, it can be assumed that
the marked decline in the air pollution level was ascribable to
22
72
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the effects of automotive exhaust emission control.
Table 3 Yearly changes in nitrogen oxide concentrations
measured at -the state-operated automotive emission
monitoring stations in Tokyo
(Unit: pphm)
1964 <65 '66 '67 '68 '69 '70 '71 '72 '73 '74 '75
Location"
NO
Kasumigaseki
N02
NO
Itabashi
N02
NO
Shinjuku
N02
(Note) 1. * Sepi
3.2 3-3
1.3 1.8
1.5 1.6
1.4 1.7*
2
2
2
1
.6 2.5
.1 1.8
.0 2.0
.7 1.8
bember - December
4.2
2.2
3.9
1.5
**
9-3
4-3
4.9
2.0
July
9-7
4.5
7-0
2.7
8.5
4.1
9-7
3.6
8.1
4.1
9-7
4.9
*#
4.6
**
3-4
7.6
4.6
10.6
6.6
4.7
3.7
6.0
3-7
8.2
4.7
4.1
3-4
5.5
2.8
6.8
3-4
4.3
3-3
— December
2. Saltzman coefficient: 0.72
iv) (Other measures for the control of automotive exhaust emission)
As we have seen in the preceding paragraphs, the source
exhaust gas control measures, as the major means of controlling
automotive air pollution, should be promoted. However, in the
urban areas, the volume of automotive traffic is such that the
source exhaust gas control alone proved to be inadequate to
control the air pollution. In cities and regions where the air
pollution has intensified with the increase in the volume of
automotive traffic, it has become necessary to regulate the
_23
73
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traffic volume and to strengthen measures designed to improve
the environment relating to automotive traffic from the long-
term point of view.
x
In the area of regulating the flow of automotive traffic,
the Public Safety Commission has teen pursuing compenhensive
measures; including the establishment of bus lanes and no-
parking areas and the enlargement of sidewalks, which are
designed to optimize the flow of automotive traffic on city
streets, rational distribution of road spaces and to curtail
the overall automotive traffic volume by about 1($.
In residential areas, in particular, efforts are being made to
separate the local traffic from through traffic by closing
streets and by regulating the speed of automobiles, and the like.
On the other hand, the Public Safety Commission is empowered
to regulate, upon request from the governor of the prefecture
concerned, automotive traffic in such protions of the nation's
highways and the areas adjacent to them, in case the air pollu-
tion caused by automotive exhaust gas reaches a certain critical
level of concentration.
Also, when the construction or rebuilding of a main road
running through areas which require the conservation of wholesome
environment is proposed, the builders of such road are required
to establish buffer zones, green belts and improve the struc-
tural design of such road. Efforts are also being made to
reduce the level of exhaust gas concentration by building multi-
level crossings or by improving the traffic flow at intersections.
24
74
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4. Monitoring
Table 4 Increases in the number of nitrogen oxide air
pollution stations in Japan
Ambient air pollution
monitoring station
State-
operated
1965
'66
'67
'68
•69
•70
'71
'72
'73
'74
3
5
7
9
11
13
15
15
15
15
Automotive exhaust emission
monitoring station
Prefecture- Total State-
operated operated
0
0
0
0
6
26
53
161
314
567
3
5
7
9
17
39
68
176
329
582
2
2
2
2
2
2
2
3
3
3
Prefecture- Total
operated
- -
- -
- —
- -
- —
- -
33 35
75 78
122 125
164 167
(Note) " - " in the above table indicates that the exact number of
the stations is unknown.
At the present time there have been established nitrogen oxide
air pollution monitoring stations and automotive exhaust emission
monitoring stations in Japan as shown in Table 4- Apart from
the above, measurements of smokestack emissions at 608 factories
are telemetrically recorded at the prefectural monitoring centers
for air pollution (as of the end of FT1976).
The control of HOx emissions is new compared with that of
SOx and the establishment of the monitoring stations on the
nationwide basis was started only recently. However, the
25
75
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importance of nitrogen ozide control measures are recognized
so much that the network of monitoring stations is being
rapidly expanded.
In Japan, measurements of NOx concentrations in the air
are made by the adsorption photometry, using Saltsman reagen
standardized by the JIS (Japanese Industrial Standards), because
it was necessary to develop a nationwide network of monitoring
stations while there any other reliable measuring method than
the Saltzman method had not yet been developed and the measuring
instruments to be used required an ease of maintenance suited
for the efficient operation of such a high-density network of
monitoring stations that about 1,570 monitoring stations are
to be established throughout the country.
The Saltzman method now in use in Japan employs the batch
system instead of the spiral tube system and therefore it is
less affected by the effects of obstructive substances.
The state-operated monitoring stations are making investigations
on the errors of measurement by this method. The chemiluminescence
method is not used in Japan because automatic calibration is
difficult at the present time.
Environment Agency is now making research and investigation
for further improvement of the measuring method so that measure-
ments can be made with greater accuracy.
26
76
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5* SOx control strategy for the future
In view of the present progress in the technological develop-
* /•
ment for controlling nitrogen oxides, it seems difficult to completely
attain in all areas the target set up by a government notification,
that is, "as a rule endeavors shall be made to attain the target in
five years (eight years in special areas such as extremely densely
populated areas). Anyway, the measures for controlling nitrogen
oxides emitted by industrial installations and motor vehicles will
be carried on as follow in the immediately future.
First, efforts will be made to grasp the progress in technolo-
gical development for the control of emission of nitrogen oxides
from stationary sources (industrial and business installations) and
mobile sources (motor vehicles) and the control on such sources will
be tightned as much as possible by March 1977* Taking such trends
of NOx control, we are planning to clarify the relationship between
the quantities of emissions from the various sources and NOx concen-
trations in the ambient air by March 1977 and then proceed to the
formulation of HOx curtailment plan, taking into account the results
of the national discussion on the control measures to be taken.
(Table 5)
The Industrial Structural Council, an advisory assembly attached
to the Ministry of International Trade and Industry, is discussing
the way the HOx control measures should be carried on and thus obtained
results will be used as a part of the national discussion in the study
of the proposed HOx curtailment plan.
27
77
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In order to provide useful informational material, Environ-
ment Agency is now endeavoring to establish simulation models, to
make assessment of NOx control techniques and the costs and effects
of the various measures to be taken. Under thus formulated NOx
curtailment plan,"the application schedule for the control standards,
including the regulation of total mass emission, on the basis of
which the measures will be carried on toward the attainment of the
ambient air quality standards for nitrogen dioxide.
28
78
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Table 5 The tentative schedule for the emission control of nitrogen oxides
Those relating to
environmental
quality standards
Others
Apr. '73 (FY1973)
Apr. '74 (FY1974)
- Ambient air quality
standards for nitrogen
dioxide established
(May '73)
Apr. '75 (PY1975)
- Review of the results
obtained from the survey
for the health effects of
compound air pollution
(particularly those of
smoke and soot) compiled
Those relating to
controls
Stationary sources
Emission standards
established (first
round) (Aug. '73)
Survey for the develop-
ment of techniques for
predicting ground level
concentrations of
nitrogen oxides (Himeji)
Mobile sources
Passenger cars
1973 exhaust control
standards
1973 regulation stand-
ards for used cars
(May '73)
Survey for the develop-
ment of techniques for
predicting ground level
concentrations of nitrogen
oxides (Kyoto and Kita-
kyushu)
Nitrogen oxide emission
standards revised and
strengthened (second
rounds (Dec. '75)
1975 exhaust control
standards (Apr. '75)
Public hearing on exhaust
control, Aug. - Oct.
-------
00
Apr. '76 (FY1976)
Apr. '77 (After FY1977)
- WHO Task Group Meeting on Nitrogen
Oxides held in Tokyo (autumn, 1976)
- Deadline for the attainment of the prescribed ambient air
quality standard for nitrogen dioxide for the areas of
attaining within 5 years (FY1978)
- Deadline for the attainment of the interim target of the
prescribed ambient air quality standard for nitrogen
dioxide for the areas of attaining within 8 years (FY1978)
OECD reveiw of environmental policy
of Japan (Nov. '76)
- Policy review for the formulation of the most appropriate
nitrogen oxide control measures
- Survey for the development of
denitrification technologies
- Review of measuring methods
- Finalization of techniques for
forecasting ground level concentra-
tions of nitrogen oxide
- Drawing-up of a model plan for total
emission reduction
- Upward revision of nitrogen oxide
emission standards (third round)
- Enforcement of total mass emission control standards
(planned)
-------
Buses and trucks
(gasolin-powered)
Diesel engine
vehicles
Apr. '73 (FY1973)
- 1973 exhaust control
standards (Apr. '73)
Apr. '74 (FY1974)
- 1974 exhaust con-
trol standards
(Oct. '74)
Apr. '75 (m975)
- 1975 exhaust control
standards (Apr. '75)
- Review of exhaust control
standards by the Experts
Committee on Automotive
Air Pollution to establish
new targets for control
Apr. '76 (PY1976)
Apr. '77 (After PT1977)
- 1976 exhaust control standards
- Survey for the development of
technologies for reducing nitrogen
oxides emission
- Announcement of 1978 exhaust control
standards (planned)
- Establishment of targets for exhaust
control
- 1978 exhaust control (planned)
-------
Measures Being Taken in Japan to
Reduce N02 and.Photochemical Oxidant in the Air
( Air Quality Bureau, Environment Agency)
Japanese Delegation
The paper will report, rfrom the administrative standpoint,
various problems related to photochemical oxidant, measures having
been taken to reduce K02 and photochemical oxidant, and the future
direction in the control of such air pollutants in Japan.
1. Episode
It was relatively in recent years that the problems of
photochemical smog started to be considered matters of primary
concern among various problems of air pollution in Japan.
In the past, the air pollution was divided into two typical
types, one being London-type smog and the other Los Angeles-
type smog, and it is widely known that the Los Angeles-type
smog is a photochemical smog.
The air pollution in metropolitan and industrial cities
in Japan was considered an intermediate type between them
judging from the conditions of the pollution and in the beginning,
sulphur oxides, suspended participates matters and carbon
monoxide which is the main element of automotive exhaust gas
were considered as typical air pollutants. Therefore, the
measures were centered on reduction of them. When the Tokyo
1
82
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Rissho High School incident occurred in July of 1970, the
control of monoxide gas was just started as a countermeasure
against automotive exhaust gas and no measure had not been taken
before that time in Japan taking into consideration photochemical
smog. It was found that the incident Was caused by photochemical
smog and since then the problem of photochemical smog has been
arousing the general public to show a serious interest in it.
On July 18, 1970, the incident occurred at the Tokyo Rissho High
School in Suginami, Tokyo. While 43 girl students were playing
on the ground, many students started to complain of irritation
in the eyes, and pain in the throats. A few of them complained
of breathing difficulty and convulsion in the limbs. Altogether
14 students were hospitalized for treatment. It was suspected
that the incident may have been caused by photochemical smog;.
Since then,, similar incidents of irritating symptoms in the eyes
and throats have been reported in Tokyo and neighboring districts.
By the fall of 1970, the number of victims reported reached
17,887 in Tokyo, Chiba and Saitama. Then in Summer of 1971,
similar cases were reported not only in the Tokyo area but also
the Osaka and Nagoya areas and the number of victims reported
reached 48,118.
2. Tentative Measures
The Environment Agency was established on July 1 of 1971
and faced with the problem of photochemical smog as its first
important task. Then the occurrence mechanism and effect of
2
83
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photochemical smog were not known quantitatively and there were
so many unknown factors to take the best step to prevent it.
However, on the basis of the understanding that hydrocarbon and
nitrogen oxides may be causing"photochemical smog, the following
tentative measures were taken.
3
84
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Tentative Measures to Prevent Occurrence of Photochemical Snog
(NQtice No.92 dated June 1, 1972
/•
sent to Prefectural governors from
Air Quality Bureau, Environment Agency)
The air pollution by photochemical reaction (hereinafter
referred to as photochemical smog) has become a serious social
problem since the so-called photochemical smog incident occurred
at the Tokyo Rissho High School, Suginami, Tokyo, in the last
Summer. The review of the frequency of warnings issued in relation
to oxidant and the number of victims reported shows clearly as
seen in the attached table that the photochemical smog has been
occurring more frequently and in wider region.
As countermeasures, the regulations for standards measures
to be taken at'an emergency caused by oxidant or N0£ were established
and the regulations for automotive exhaust gas were expanded under
Air Pollution Control Law In additions, the work to establish
environmental standards for nitrogen oxides and oxidant, the study
of drastic measure to reduce automotive exhaust gas and nitrogen
oxides from stationary sources,, and the investigation into the
occurrence mechanism and effect on the human health of photochemical.
smog are under way.
Today, the occurrence mechanism and effect of photochemical
smog are fairly well understood, but there are still many unknown
4
85
-------
aspects. Thus, a further research is required to understand
those unknown aspects in order to establish countermeasures
against photochemical smog.
However, in view of recent occurrences of photochemical
smog, the following tentative measures should be taken in
metropolitan and" industrial cities arid their surrounding areas
from June to September in order to prevent the occurrence of
photochemical smog and health hazard.
As the measures are strongly related to the administrative
policies of local governments, a sufficient information should
be supplied to the local governments concerned and a system
of close communication and cooperation should be established
among the agencies concerned.
The same letter has been sent to the Police Agency, the
Ministry of Education, the Ministry of Health & Welfare, the
Ministry of International Trade & Industry, the Ministry of
Transport and the Ministry of Labor.
1. Measures against Stationary Sources
(l) Measures against nitrogen oxides
At present, the only effective way available to control
the exhaustion of nitrogen oxides from stationary sources is
to reduce consumption of fuels. Therefore, when the weather
condition is very likely to cause photochemical smog, it should
be appealed to general households, factories and plants to reduce
5
86
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the consumption of fuels and stop burning waste products if
it is not urgent.
(2) Measures against hydrocarbon
(a) As evaporated hydrocarbon is exhausted into the air when oil
is supplied into oil storing tank at gas station or gas storage
or due to change in the -atmospheric change, the owners of such
oil storing facilities should be instructed to install a device
to prevent exhaustion of hydrocarbon or adopt a system of returning
evaporated hydrocarbon into tanker or tank wagon.
(b) Hydrocarbon is often exhausted into the air from workshops
using organic solvent or products containing organic solvent.
Factories and plants using them should be requested to control
the exhaustion of hydrocarbon.
-(c) If the weather condition is very likely to cause photochemical
smog, the general public should be asked to cooperate to postpone
any action which is likely to exhaust hydrocarbon into the air.
2. Measure against automotive
(l) An automobile exhausts photochemical smog producing substances
such as hydrocarbon and nitrogen oxides when it is operated. At
present, there is no effective technology to reduce the exhaustion
of gas from automobile. Therefore, if the weather condition is
likely to cause photochemical smog, the owners and drivers of
automobiles should be advised not to drive automobiles unless it
is urgently necessary to do so, in cooperation with the agencies
6
$7
-------
concerned. In addition, the local authorities of the districts
where there have been a large number of victims of photochemical
smog should consult with the local public safety commission
concerned on the effective anft appropriate measures to be taken
to prevent the occurrence of victims of photochemical smog,
such as reducti'on of automotive traffic which produces polluting
substances, in anticipation of the occurrence of photochemical
smog of emergency level.
(2) Periodical inspection and servicing of automobile
Insufficient servicing of engine system considerably
increases the density of automotive exhaust gas. The users of
automobiles, therefore, should be instructed to carry out perio-
dical inspection and servicing of automobile required under the
Road Transportation Vehicle Act, in cooperation with the agencies
concerned.
(3) Recommendation to attach a device to prevent exhaustion of gas
from automobile
The work to develop such a device is under way. With the
catalytic preventing device, there are still unsolved problems
of purification efficiency, durability and occurrence of related
pollutions, but as it is considered fairly effective for a shorter
use under a strict control, the attachment of the device should
be recommended to the users of automobiles, especially during
periods of frequent occurrences of photochemical smog, in view of
the recent frequent occurrences of photochemical smog*
7
88
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(4) Supervision of mixing of olefin hydrocarbons and aromatic
hydrocarbons
As for olefin and aromatic hydrocarbons contained in
gasoline, the plan for non-leaded gasoline is being carried
out to reduce the amount of those compounds while keeping
the level of octane value necessary 'for normal operation of
automobile. It is requested to investigate the actual condi-
tions of mixing of such compounds at the stage.of distribution.
If it is necessary, any one who is in violation of the law should
be warned and it should be reported to the agency.
» Establishment of Warning System
As it is necessary to forecast photochemical smog for
effective implementation of the measures against photochemical
smog, a close communication should be maintained with the weather
forecasting agency to gather informations on weather. A system
of forecasting photochemical smog should be established. Under
such a system, an appropriate forecast of photochemical smog
will be made taking into consideration weather conditions and
change in the density of oxidant at the point where the air
pollution will be observed.
According to the past investigations, the density of oxidant
considered an indicator of photochemical smog tends to get higher
under the following weather conditions, though there are some
exceptional cases due to other factors;
8
89
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a. The inclination of atmospheric pressure is gentle and a
weak wind remains.
b. There is a sunshine.
c. The atmosphere is stable and there is an inversion layer
of front or sinking nature.
c. The temperature is'over 20 C in general and the humidity
is less than 75 percent.
4. Health Measures
(l) Strengthening of supervising system and information network
As for health measures against health damages due to photo-
chemical smog, it is necessary to disseminate informations to the
general public on photochemical smog and take appropriate measures
promptly if any health damage is caused by photochemical smog in
addition to the strengthening of general health measures. In
order to do so, it is required to establish a strong system of
health measure implementation through utilization of the facilities
of public health centers and cooperation with the agencies con-
cerned so that consultation, exhcnage of informations and finding
of actual conditions of health damages may be smoothly carried out.
(2) Thorough dissemination of informations
With respect to health measures against photochemical smog,
it is most important to get the cooperation of the general residents
through deepening their understanding of photochemical smog.
Thus, mass media, educational organizations, doctors' associations,
9
90
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womens1 organizations, and local groups should be asded to
cooperate for thorough dissemination of informations.
(3) Measures to be taken when a health damage occurs
a. Prior measure
Among the recent victims of photochemical smog in Japan,
the cases with serious symptoms such as breathing difficulty,
numbness in the four limbs and convulsion in the four limbs,
requiring hospitalization for treatment, were reported. In
anticipation of possibility of occurrence of these types of
health damages, it is necessary to establish a system in advance
so that proper emergency measures can be taken with cooperation
of medical institutions.
b. Measures to be taken when health damages actually occur
Efforts are wanted to conduct the following investigations,
if necessary, to ascertain the actual conditions of health damages
that occurred and to probe into their causes.
A. Survey of health damages
(a) Survey of occurrences of health damages
Survey of the number of victims, main symptoms and
onset conditions of symptoms in the region where serious
cases have occurred and its surrounding areas
(b) Health examination of victims, and clinical and medical
examination
If it is found that a victim requires a medical treat-
ment as a result of health examination, the clinical record
.of the victim should be studied as much as possible and kept.
10
91
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( (c) Survey of group of victims
Survey of special circumstances (even or lecture) of the
group of victims, conditions of health management and meals
before occurrence.
(d) Others
B. Survey of environmental conditions
(a) Survey of weather factors
Survey of weather'factors including temperature, humidity,
wind direction and wind velocity before and after occurrence,
(b) Survey of air pollutants.
Survey of the density of major pollutants including sulphur
oxides, nitrogen oxides and suspended particulate matters as
well as oxidant, in addition, survey of the density of other air
pollutants such as aldehyde compounds and sulfuric acid mist
(c) Survey of stationary sources
Survey of smoke producing facilities, burning of waste
products, and facilities and actions which may produce irritating
substances
(d) Survey of mobile pollution producing sources
Survey of road traffic
(e) Other necessary surveys
Survey of the topography (ups and downs, degree of openness),
things (buildings), arragements of trees and damaged plants.
c. Measures to be taken after survey
It is considered that the density and life of various pollutants
as well as factors of individual body such as sex, age and health
condition including both mental and physical aspects are related to
11
92
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health damages. In evaluating and making a judgement of the
results of the survey, such factors should be carefully taken into
consideration and at the same time, necessary measures such as
disclosing of the results of the survey should be taken.
5«. Report of issues of emergency warnings
If forecast warning or causion concerning ozidant is issued
or if there is any report of damage appearing to have been caused
by oxidant, such reports and warnings should be summarized each
week (from Sunday to Saturday) using the Form 1 and the summary
should be reported by the following Saturday latest. In so doing,
it is requested to report the damages caused by photochemical
smog, using the Form 2, if it is possible.
In addition, when there is any serious symptom such as
convulsion in the four limbs or breathing difficulty, it should
be promptly reported by teLephone and the progress thereafter.
If a warning is issued for the first time or a case of
damage is reported for the first time, it should be immediately
reported by telephone.
12
93
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3. Photochemical Smog Control Promotion Conference
On June 19 of 1972, the Government'established "Photo-
chemical Smog Control Promotion Conference" in order to facili-
tate a close communication among the administrative agencies
concerned with the measures against photochemical smog and
promote the execution of comprehensive and effective counter-
measures, in view of the importance and urgency of the problem
of photochemical smog and the« necessity of comprehensive counter-
measures against photochemical smog. The conference is composed
of the members as shown in Table 3-1.
Table. 3-1 Members of Photochemical Smog Control
Promotion Conference
Environment Agency
Prime Minister's Office
National Police Agency
Science and Technology
Agency
Ministry of Education
Ministry of Health and
Welfare
Ministry of Agriculture
and Forestry
Ministry of International
Trade and Industry
Ministry of Transport
Ministry of Labor
Ministry of Construction
Ministry of Home Affairs
Director of Planning and Coordination
Bureau
Director of Air Quality Bureau
Director of Traffic Safety Measure
Bureau
Director of Traffic Bureau
Director of Research Coordination Bureau
Director of Physical Education Bureau
Secretariat Councilor
Secretariat Technical Councilor
Director of Industrial Location and
Environmental Protection Bureau
Director of Machinery and Information
Industaies Bureau
Secretariat Councilor
Derector of Labor Standards Bureau
Director of City Bureau
Assistant Director of Fire Defense Agency
13
94
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4. Environmental Standards for Nitrogen Oxides etc.
Meanwhile, the Central Pollution Control Council established
"Special Committee on Environmental Standards for Nitrogen Dioxide etc. "
in the Air Division in view of the fact that the condition of air
pollution by nitrogen dioxide and photochemical oxidant has been
getting worse year after ye'ar and the stage has been reached
where such air pollution cannot be overlooked any longer from
the standpoint of its effect on human health, and prepared a
report of the special committee on the environmental standards
for nitrogen dioxide after studying the effects and the proceduces
to measure nitrogen dioxide and photochemical oxidant in the air.
As for nitrogen dioxide, the environmental standards were
established not from the standpoint of controlling formation of
photochemical oxidant, but from the standpoint of its effect
on human health. The Central Pollution Control Council recommended
the maximum value of 0.02 ppm per hour as an average value of a
day with respect to nitrogen dioxide and that of- 0.06 ppm with
respect to photochemical oxidant as the environmental standards.
At the same time, the target period of five years with respect
to nitrogen dioxide (eight years in some districts) and that of
shortest time with respect to 'photochemical oxidant were deter-
mined. In addition, the Council recommended to carry out the
following measures both in the comprehensive•and positive manners
in order to achieve the target of the environmental standards.
14
95
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"On Problems Accompanying the Establishment of the
Environmental Standards for N02"
In order to achieve and Maintain the target of the
environmental standards, it is necessary to implement the
following measures both comprehensively and positively.
1. Development of control technology as a national project
As for a technology to control production of nitrogen
oxides in the stationary sources, it is planned to develop a
denitration technology and a burning technology to be put into
practical use within five years, and necessary assistances in
terms of finance and taxation should be provided to facilitate
technological development and introduction of technologies
developed in the private sector, in view of the urgent necessity
of technological development.
In addition, the same things should be done with develop-
ment of control technology necessary for tightening control of
automotive exhaust gas, dramatic new energy source which does
not cause any environmental pollution and its production
technology.
2. Enforcement of the regulations for pollutants producing sources
In order to reduce the total amount of exhaustion of
nitrogen oxide into the air, the following measures should be
taken and at the same time, the introduction of a control system
based on the total allowable amount of exhaustion of pollutants
15
96
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in the area should be examined.
(l) A rational control of exhaustion from stationary sources
should be enforced through improvement of burning system and
burning conversion which are "presently possible. In the future,
when a control technology such as a denitration technology has
•
been developed 'for practical, use, the control of exhaustion
should be immediately tightened.
(2) The control with tougher long-term target for automotive
exhaust gas should be enforced with respect to new automobiles.
With respect to used cars, the necessary control should be done.
3« Planning and execution of pollution control program
In order to achieve and maintain the level of the environ-
mental standards, a pollution control program should be planned
and executed under the Basic Law for Environmental Pollution
Control.
4» Execution and promotion of environmental assessment
An environmental assess-ment technique should be developed,
effective and proper for city and industrial developments, and
thorough execution.of such environmental assessment, and the
rationalization of land utilization should be achieved for
effective control of air pollution by nitrogen oxides.
5- Improvement of transportation system
In order to make a contribution for effective control of
air pollution by automobile traffic, the study of the metropolitan
public transportation system should be facilitated and at the
16
97
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same time, this quantity of pollution causing nitrogen oxides in
the metropolitan areas should be reduced through absorption
of increasing demand for transportation into the public trans-
portation system.
6. Effective use of energies
• •
The quantity of pollution causing nitrogen oxides should
be reduced through effective use of energies by means of regional
air-conditioning work and improvement of burning system.
Also, as it is known that heating devices, too, cause
pollution by nitrogen oxides, improvement and development of
heating systems and equipment should be carried out.
7« Establishment of system of monitoring and measuring
For accurate measurement and evaluation of conditions of
air pollution by nitrogen oxides and making a contribution for
execution of proper control countermeasures and evaluation of
effectiveness of such countermeasures, it is urgently required
to facilitate the establishment of a system of monitoring and
measuring and at the same time, an effort should be made to manage
and maintain the system in a proper form.
8. Promotion of investigation and research
Together with promotion of execution of the various measures
mentioned above, investigation into and research on the effect
of nitrogen oxides and measuring procedure should be carried out.
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"On problems accompanying establishment of the
environmental standards for Oxn
In order to achieve and maintain the level of the environ-
mental standards, it is necessary to positively promote the
execution of the following measures in addition to the measures
to maintain and achieve the level of the environmental standards
for nitrogen oxides, in view of the fact that the main substances
which cause photochemical oxidant are nitrogen oxides and hydro-.
carbon.
Promotion of investigation and research
It cannot be necessarily said that the actual conditions
and effects of air pollution by photochemical reaction are suffi-
ciently understood in Japan. It is necessary, therefore, to
carry out a comprehensive and detailed study in order to under-
stand them, taking into consideration special weather conditions
in city areas.
In addition, the mechanism of production of air pollutant
by photochemical reaction of ozone, PIN or formaldehyde, effect
on human health, damage of visibility, effect on living environ-
ment such as damage of plants and method of measurement should be
studied.
In addition, the relationship between production and use
of products containing gasoline, organic solvent or hydrocarbon
and air pollution by photochemical reaction should be studied, too.
18
100
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2. Control of Pollution producing sources
In order to control air pollution by photochemical oxidant,
it is necessary to effectively control pollution producing sources
in accordance with the progress of the studies 'mentioned above.
In view of urgent necessity of countermeasures against photo-
chemical oxidant, the following measures should be taken for a
time being.
(l) A necessary controlling measure should be taken according to
the actual conditions of exhaustion, leakage and evaporation of
pollutants in the process of production, storage and use of
gasoline and organic solvent in industrial plants and business establish
ments.
(2) Exhaustion of hydrocarbon with automotive exhaust gas should
be more tightly controlled. In addition, a system of inspecting
and servicing engines should be improved.
3. Execution and promotion of environmental assessment
Effective and proper technique of environmental assessment
for city development and industrial development should be developed
and an environmental assessment should be executed in order to
control air pollution by photochemical oxidant, in view of forma-
tion mechanism of photochemical oxidant.
4» Development of control technology
In view of urgent necessity of developing technology to
prevent leakage, exhaustion and evaporation of hydrocarbon from
stationary sources.and mobile sources, the development of the
technology should be-facilitated.
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101
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5» Establishment of system of monitoring and measuring
For accurate measurement and evaluation of condition of
air pollution by photochemical oxidant, and execution and judge-
ment of effect of preventive measure, it is urgently required to
establish a system of monitoring and measuring. In addition,
a similar system shou,ld be established for hydrocarbon and ozone.
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"Special Committee Report on Environmental Standards for
Nitrogen Oxides etc."
Jane 20, 1972.
Environmental Standerds for nitrogen oxides etc.
Committee of the Air Division, the Central Pollution
Control Council.
The special committee on "environmental standards for
nitrogen oxides etc. reports to the Central Pollution Control
Council Air Division as follows. It should be noticed here that
the committee took over the work of the Special Committee on
Environmental Standards for Nitrogen Oxides of the Living Environ-
ment Council Pollution Division of the Ministry of Health and
Welfare with respect to this report.
1. -Introduction
Nitrogen oxides etc in this report include NOx, photochemical
oxidant, ozone and so on.
Among nitrogen oxides, nitrogen monoxide and nitrogen
dioxide are especially important in terms of their effects on
living environment. Nitrogen oxides are also produced as a
result of natural phenomena such as metabolism of microorganism
in the soil. It is known that the background concentration of
nitrogen dioxide"in the air is less than 0.003 ppm. Ozone falls
down from the stratosphere and its concentration on the surface
of the earth is less than 0.05 ppm.
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103
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Kitrogen monoxide (NO) is produced and exhausted into the
atmosphere when the air is heated by stationary sources such as
thermoelectric power station and furnace and mobile producing
sources such as automobile. Then, it is oxidized in the air
to become nitrogen dioxide (N0?). Nitrogen oxides are also
produced by the chemical processes such as nitrification
process and discharged directly into the air. The nitrogen
oxides produced as mentioned above cause regional and local
air pollution. In Japan, the air pollution by nitrogen oxides
rapidly became worse in the past ten years.
If nitrogen dioxide and hydrocarbon, especially non-
saturated hydrocarbon, exist together and are exposed to
sunlight, secondary air pollutants are produced. If there
is any sulfur dioxide, it is oxidized to become sulfuric acid
mist. In this case, the air pollution by photochemical reaction
is even worse.
In general, today, nitrogen monoxide and nitrogen dioxide
are together called nitrogen oxides. They have an effect on
human health, cause damage of visibility and color the air.
Our present knowledge about its effect is mostly about
nitrogen dioxide, and we do not know much about the effect of
ni'trogen monoxide. Therefore, the environmental standards
only for nitrogen dioxide will be recommended in this paper.
As for nitrogen monoxide, it is expected that necessary data
for establishment of environmental standards for it will be
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obtained with the progress of research.
Among the substances produced by photochemical reaction
when nitrogen dioxide and hydrocarbon coexist in the air,
s
the following substances are especially noticed. They are
ozone (Oj), nitrogen dioxide, PAH and its homologous compounds,
oxidized substances such as 'peroxide, reductive compounds such
as formaldehyde and acrolein, aerosol and highly active free
radical whose effect is not known, but which should be noticed.
The total effect of those substances is generally called the
effect of photochemical oxidant.
Mucous membrane irritating symptom, severe effect on
respiratory organs and other internal organs, effect on tissues,
cracking of rubber, bad effect on plants, damage on agricultural
products and fading of clothes are some of effects known as
the effects of photochemical oxidant.
Here, we call oxidized products, excluding nitrogen
dioxide, produced by photochemical reaction photochemical
oxidant. It is measured by a method using neutral potassium
iodide solvent. It is known that the measured value is mostly
due to ozone. Therefore, with the understanding that photo- .
chemical oxidant is mostly ozone, we recommend the environmental
standards for photochemical oxidant which is an indicator of
pollutants produced by photochemical reaction.
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2. Method of measurement
Both in the case of regional air pollution and local
air pollution, the measurement of pollution by nitrogen oxides
must be done at places so that pollution and trend of pollution
will be well understood, and judgement of effects, establish-
ment of preventive measures against pollution, and evaluation
of effect of the measures can be effectively carried out.
A sample air should be collected at the level of human mouth.
As a rule, it should be collected at a height between 1.5 a and
10 m above the ground.
The measured value of photochemical oxidant requires
correction with respect to nitrogen oxides. Therefore, it is
necessary to measure nitrogen oxides at the same place where
photochemical oxidant is measured.
2-2-1 Measurement of nitrogen oxides
2-2-1.1} General matters
It is better to continuously measure nitrogen dioxide,
and in totalizing the results of measurement, the data
should be totalized for each hour. The unit of measurement
is determined according to the concentration of- nitrogen dioxide
in the air. Generally speaking, the device should be able
to measure from several ppb up to 2 ppm.
In order to find out the condition of pollution by
nitrogen oxides, it is desirable to measure not only
nitrogen dioxide but also nitrogen monoxide.
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2-2-1.2) Standard method
The method of measurement based on the absorptiometry
using Salzurann reagent is a standard method for measurement
of density of nitrogen oxides. However, other method can also
be used if it shows the same result.
2-2-2 Measurement of photochemical oxidant
2-2-2.1) General matters
In general, oxidant is a general name of oxidized
substances which free iodine from neutral potassium iodine
solvent. Using this reaction, photochemical oxidant is
measured. It is desirable to continuously measure photochemical
oxidant and in totalizing the results of measurement, the data
should be totalized for each hour.
The device should be capable of measuring from several
ppb to 1 ppm.
2-2-2.2) Standard method
The method of measurement based on the absorptiometry
using neutral potassium iodine is a standard method for measure-
ment of photochemical oxidant. Other methods such as coulometric
method can be used, too, if the same result can be obtained.
With the standard method, the measured value of photochemical
oxid.ant should be corrected with respect to the density of nitrogen
dioxide. Also, as there is an effect of reductive substances
such as sulfur oxide, a paper containing chromium trioxide is
used to eliminate such -effect. In this case, it is necessary.
25
107"
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to make a correction with respect to the density of
nitrogen monoxide as nitrogen monoxide in the air is
oxidized to nitrogen dioxide, which causes some effect
on the measured value of* oxidant.
The density of oxidant with correction as to the
• •
density of nitrogen oxides is mostly due to ozone.
2-2-3 Measurement of ozone
As mentioned above, if photochemical oxidant is measured
"by a standard method, most of the value is due to ozone and it
is very clear, therefore, that it is more desirable to measure
ozone directly. Today, there is a cheiailuminescence method
utilizing a reaction with ethylene as a usable method of
measurement of ozone. With this method, ozone can be selectively
measured without any effect of sulfuric dioxide or nitrogen
dioxide. This method is being improved for practical use and
it is hoped that it will be adopted as a standard method in
the future.
2-3 Additional remark
As it is necessary to collect data from future researches
and studies in order to make a judgement on the condition of
air pollution by nitrogen oxides and its effect, it is strongly
desired that these methods of measurement will be utilized
together with the standard methods mentioned above, in view of
the present situation that the method of selectively measuring
ozone will soon be put into.practical use.
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In addition, it is strongly desired that the measurement
of hydrocarbon will soon be done as a daily work, in view of
the occurrence mechanism of photochemical oxidant.
3» Effect on human body
3-1 Effect of nitrogen oxide
The effect of nitrogen monoxide is not sufficiently known
yet, partly due to difficulty of experiment. If an animal is
exposed to extremely dense nitrogen monoxide, it develops
paralysis and convulsion which are due to damage in the central
nerve system. It has a strong affinity to blood cells.
According to the test tube experiment, its affinity is several
hundred stronger than carbon monoxide. In the animal experiment
using an extremely high dense nitrogen monoxide, the formation
of nitrogen monoxide blood cells and methemoglobin has been
observed. At present, its effect on human body is not known
much. Future study may show that nitrogen monoxide should be
more seriously considered than nitrogen dioxide.
Nitrogen dioxide possesses a characteristic of easily
reaching the deep part of respiratory organ regardless of
existence of suspended particulate matters. It has been noticed
in the human experiment that nitrogen dioxide and suspended
particulate matters possess a mutually additive effect if they
coexist.
Therefore, it was known from early time that nitrogen
dioxide has an effect of irritating respiratory organs and its
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109
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poisoning has been noticed as an occupational disease.
The cause of' death by acute poisoning of high dense
nitrogen dioxide is an edema of the lungs in the animal experiment-
and the occupational disease. As for chronic effect, it is
concerned that it may cause chronic bronchitis and emphysema of
the lungs.
We are able to smell nitrogen dioxide with the concentration
of 0.12 ppm. This value is-lower if sulfuric dioxide exists
together. A significant increase in air resistance in the human"
air-passages may occur within 10 minutes if the density of
nitrogen dioxide is 16.9 ppm. Prom the reaction against increase
in air pressure, it can be seen that sulfuric dioxide and nitrogen
dioxide possess a mutually additive effect.
In the animal experiment, an effect on the lung cells is
seen with the exposure of the subject to the nitrogen dioxide
of 0.5 ppm for four hours. If an animal is exposed to nitrogen
dioxide of 0.5 ppa for a several month, it may develop bronchitis
and emphysema of the lungs.
It has been pointed out that an animal becomes sensitive
to influenza virus and bacteria pneunoiae, its life gets shorter
and its bacteria eliminating power is weakened if it is exposed
to nitrogen dioxide. For example, if an animal is exposed to
the nitrogen dioxide of 0.5 ppm for 12 months and infected with
bacteria pneuraoniae, fatal ratio will increase and its bacteria
eliminating power will be weakened.
If an animal is exposed to the nitrogen dioxide of 10 ppm
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110
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for two hours a day and infected with influenza virus, it will
develop intestitial pneumonia, and its pathologival symptom will
get worse with the increase in days of exposure. With six-month
exposure to the nitrogen dioxide of 0.5 ppn, a reactive multipli-
cation of epithelial cells of peripheral bronchus and minor
emphysema of the .lungs will be seen. If the subject is infected
with influenza virus, its symptom of pneumonia will be more clear
and the adenoma-like multiplication of epithelial cells of peri-
pheral bronchus will be observed.
This adenoma-like multiplication should be carefully
noticed. The possibility of nitrogen dioxide causing bronchial
asthma has been demonstrated in the animal experiment. It has
also been shown that the production of carbon monoxide bloodcell
increases if carbon monoxide coexists with nitrogen dioxide.
It has not been much studied how extensively the residents
are being affected acutely or chronically at the present density
level.
In America, and it has been reported that the frequency
of infection to influenza and absence among school children
in the region with pollution by nitrogen dioxide and nitrate
and with no sulfuric dioxide pollution had increased.
According to the report, the concentration of nitrogen monodixe
was 0.062 to 0.109 ppm and that of nitrate 3f8.ug/m3 or higher.
In Czechoslovak, the survey of the school children in the region
polluted both by sulfuric dioxide and nitrogen dioxide has been
29
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carried out.
As mentioned above, it should be noticed that nitrogen
dioxide has a mutually additive effect with sulfuric diowide.
. s
In Japan, the pollution only by nitrogen dioxide is exceptional
occurring only locally. As nitrogen dioxide and sulfuric
dioxide coexist in many Qases, in examining the environmental
standards for nitrogen dioxide, the existence of sulfuric dioxide
should not be ignored.
Epidemiological survey of frequency of chronic bronchitis
has been carried out in several occassions in Japan. In the
report, it should be first noticed that the frequency of chronic
bronchitis among the adult over 40 years old is 3 percent in the
region with no air pollution. On the other hand, the frequency
of simple chronic bronchitis with cough and sputum is higher
than 5 percent among the male workers of local authorities in
Tokyo with the yearly average concentration of 0.05 ppm per
hour or below of sulfuric dioxide during 1968 and 1971. In
this case, the yearly average concentration of nitrogen dioxide was
higher than 0.042 ppm per hour.
The epidimiological survey of frequency of housewives with
cough and sputum of continuous nature carried out in six districts
nationwide in the winter of 1976 - 1971 demonstrated a high
correlation between the frequency and the density of nitrogen
dioxide. In this survey, the density of nitrogen dioxide was
measured for 8 to 72 hours a month during three months covering
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the month in which the survey was done. The average concentrations
of nitrogen dioxide during the period mentioned above was 0.029
ppm in the district with the frequency of higher than 4 percent.
It is well known that the frequency of adult women with the
symptom is lower than that of adult men.
3-2 Effect of photochemical, oxidant
The effect of photochemical oxidant is similar to that of
nitrogen oxides. It should be noticed that the effect of photo-
chemical oxidant is far stronger than that of nitrogen oxides.
Photochemical oxidant is mostly ozone and the effect of ozone
is as follows:
According to the animal experiment, the absorption of ozone
in the upper air-passages is limited and ozone reaches the deep
part of the respiratory organs fairly easily. With four-hour
exposure to ozone of the density of 1 ppm, a slight pulmonary
oedema developed 20 hours after exposure. With long-period exposure,
bronchitis, bronchiolitis, pulmonary emphsema, pulmonary fibrosis
and adenoncus developed. With three-hour exposure to ozone of
0.25 to 0.5 ppm, an increase in the resistance of air flow was
observed. With one-hour exposure to ozone of 1 ppm, a symptom
which led one to suspect a change in the proteins composing lung
cells was recognized. The toxicity of ozone gets stronger if
an animal is subjected to exercise.
The increase of sensitivity to bacteria due to ozone is
similar to that due to nitrogen dioxide. An increase was noticed
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already with three-hour exposure to ozone of 0.08 ppm. It has
been confirmed in the animal experiment that the possibility
of ozone causing bronchial asthma is higher than that of nitrogen
dioxide.
Vhile it is known that animals develop tolerance to acute
exposure, it is not known if they do so to chronic exposure.
In the human experiment, no definite effect was observed
up to one-hour exposure to ozone of 0.1 ppm. ¥ith one to two-
hour exposure to ozone of 0.5 to 1.0 ppm, the increase in the
resistance in the air-passages, the weakening of the capacity
of the lungs dispersing carbon monoxide and the reduction of the
lung breathing capacity were observed. In addition, the symptoms
were worse when the subjects had an exercise. The above were
average reactions and there were individual differences.
Therefore, it has been pointed out that a special attention
should be paid to those with high sensitivity.
With a long-period exposure, no definite effect was observed
among the factory workers when the density of ozone was less than
0.2 ppm. With the density of 0.3 ppm, irritation in the nose
and throat was observed. With three-hour exposure per day for
12 six-day weeks, the weakening of lung breathing capacity was
observed.
We smell ozone at the density of 0.02 ppm.
The above is the result of the experimental study. The effect
of photochemical oxidant in the actual situation on the residents
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is as follows.
According to the study in America, a damage of plants
was observed with four-hour exposure to ozone of 0.05 ppnu
¥ith a short-term exposure to* that of higher than 0.1 ppm, an
irritating symptom in the eyes developed* The frequency of fit
of asthma patients increased with the peak density of 0.13 ppm,
which is equivalent to hourly average of 0.05 to 0.06 ppm.
The aggravation of chronic respiratory disease occurred with
the hourly average concentration of 0.2 to 0.7 ppm. But it was also
reported that it did not occur with the hourly average concentration of
0.06 ppm. The athletes of cross country showed a statistically
significant increase in the time when they were exposed to ozone
of the hourly average density of 0.03 to 0.30 ppm before start.
• The effect of photochemical oxidaht on the residents has
not been sufficiently studied in Japan. There have been
complaints of damages of agricultural products and plants, and
irritating symptom in the eyes by the residents, with the
photochemical oxidant of 0.10 ppm. The effect of ozone
during exercise cannot be ignored as observed in the nrntngl
experiment, and there have been reports of school children
having suffered while exercising. In 1971, an incident occurred
when a photochemical smog developed in the southern part of Osaka.
The students developed irrtating symptom in the eyes and respira-
tory organs while exercising.
In this case, the hourly concentration of ozone was higher than
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0.2 ppm, that of sulfaric dioxide higher than 0.05 ppm, that
of sulphur acid mist 6-10 ug/m3 and that of nitrogen dioxide
0.05 ppm.
3-3 Additional remarks
It is necessary to notice that the effects of nitrogen
dioxide, ozone and photochemical dioxide on human living environ-
ment are cracking of rubber and damages of plants besides
uncomfortableness, smell and disturbance of visibility.
The effects of nitrogen oxides, ozone and photochemical
oxidant are mainly on the respiratory organs, especially lungs.
The paper, therefore, paid a special attention to this aspect.
It should be pointed out that these pollutants may have some
effect on blood, cerebreum, heart, kidney and liver, and may be
carcinogenic depending on density and the period of exposure.
4. Summary
¥e propose the environmental standards to be maintained
throughout the year for nitrogen dioxide and photochemical
oxidant on the basis of the methods of measurement and the data
of the effects on human health mentioned above as follows:
(ij As for nitrogen dioxide, especially its chronic effects are
concerned. Also, as it has a mutually additive effect with
sulfuric dioxide, the daily average of hourly value should be
less than 0.02 ppm.
(2) As for photochemical oxidant, the hourly average value of less
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than 0.06 ppm should be maintained in order to prevent the
effect of short-period exposure.
The report is the result of examination of the data obtained
so far and proposed the conditions of judgement of nitrogen
dioxide and photochemical oxidant.
It is necessary to( make further efforts for progress in the
study of method of measurement and effect, especially the effect
and that of combined pollution of nitrogen monoxide, hydrocarbon
and ozone, and method of measuring density in the environment.
As studies progress on effect of such substances on human
health and environment, the environmental standards should be
periodically reexamined and revised if necessary.
Members of the Special Committee on the Environmental
Standards for Nitrogen Oxides
Takeo Suzuki
Shun Araki
Toshio Ohdaira
Kiyoshi Kawamura
Shin Suzuki
Kasaharu Sotomura
Toshio tfoyama
Chairman, Central Pollution Countermeasures
Council
Professor, Engineering, Tokyo Metropolitan
University
Director, Air Dept, Tokyo Pollution Research
Institute
Director; Earch Chemistry Dept, Weather
Research Institute
Professor, Engineering, University of Chiba
Director, Environmental Chemistry, National
Institute of Hygienic Sciences
Prof. Medical Dept., Keio university
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Taichi Nakajima Manager, Labor Hygene, Osaka Institute of
Public Health
Tohru Fujii Director, Osaka Pollution Monitoring Center
Naoomi Yamaki Director, Pollution Resource Research
Institute, Industrial Technical Institute
Eiji Yokoyaiaa Director, Occupational Disease, Labor Hygene,
National Institute of Public Health
Hiroshi Vatanabe Director, Hyogo Institute of Pollution
Following the recommendation, the Environment Agency proclaimed
the environmental standards for air pollution as follows:
Environmental Standards for Air Pollution
(May 8, 1973)
The environmental standards for air pollution will be notified
as follows under the provision of Article 9 of the Basic Law for
Environmental Pollution Control (Law Ho. 132, 196?) and "Environmental
Standards for Suspended Particulate Matter" will be repealed.
The standards desirable to protect human health with respect
to the environmental conditions of air pollution stipulated in
provision 1 of Article 9 of the Basic Law for Environmental Pollution
Control (hereinafter called environmental standards) and the time to
be achieved will be as follows.
I. Environmental Standards
(l) The environmental standards for each substance should be as
mentioned in the table below.
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(2) The environmental standards in 1 for each substance mentioned
in the table should be based on the value measured at a place
where it is possible to accurately judge the condition of air
pollution by the said substance, by the method mentioned in
the table.
.(3) The environmental standards in 1 will not be applied in areas
such as industrial areas, vehicle roads, and any other places
where the general public usually do not spend their daily life.
II. Time to be Achieved
(l) The environmental standards for carbon monoxide, suspended
particulate matters and photochemical oxidant should be main-
tained or achieved as early as possible.
(2) The environmental standards for sulfuric dioxide should be
maintained or achieved within 5 years as a rule.
(3) The environmental standards for nitrogen dioxide should be
maintained or achieved as early as possible within 5 years.
However, in regions of high population density or large-scale
industrial areas, the interim target mentioned below should
be achieved within 5 years if it is difficult to achieve
the final target even with comprehensive measures and the
environmental standards should be achieved within 8 years
through development of denitration technology and other control
technology.
Interim target The number of days with less than daily
•>
average of 0.02 ppm per hour of nitrogen dioxide should be
* i
more than 60 percent of the total days throughout the year.
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Table
Substance
Sulfuric
Dioxide
Carbon
Monoxide
Suspended
particulate matter
Nitrogen
Dioxide
Photochemical
Oxidant
Environmental
Standards
The density
should be less
than 0.04 ppm
in daily
average per
hour and less
than 1 ppm per
hour
The density should The density should be
be less than 10 less than 0.10 mg/m?
ppm in daily in daily average per
average per hour hour and less than
and less than 0.20 mg/cm? per hour
20 ppm in 8-hour
average per hour
The density should
be less than 0.02
ppm in daily
average per hour
The density ah
be less than 0
ppm per hour
Method of
Measurement
KJ
o
Remarks
1.
2.
Conductometric
analysis
Method to use
non-dispersive
infrared analyzer
Weight concentration
'measuring method by
filter collection or
light scattering
method
Absorptiometry
Absorptionetry
using neutral
potassium iodide
or conlometric
method
Suspended particulate matters are particulate matters floating in the 'air of less than 10 micron
in diameter.
Photochemical oxidants are oxidized matters produced by photochemical reaction such as ozone, PAN
and so on, excluding nitrogen dioxide (only those which free iodine from neutral potassium iodine
solvent are included)
-------
5. Emission Control of Air Pollutants from Automobiles and
Stationary Sources
5.1 Emission Control of Automotive Exhaust Gas
As mentioned in the preceding section, it has been found
through a number of studies and surveys by the Special Committee
that both photochemicaltoxidant and nitrogen oxides have various
effects on human health and photochemical oxidant is produced
from nitrogen oxides and hydrocarbon. Moreover, cases of health
damages due to, it seem, photochemical smog are still prevalent
in Tokyo and other large cities, creating serious social problems.
Therefore, the following controls have been carried out.
(lO Emission Control of Automotive Exhaust Gas
The emission control of automotive exhaust gas started
• with the control of carbon monoxide exhausted from new cars
in September, 1966. Later, hydrocarbon and nitrogen oxides
have been added for control to gradually tighten the emission
control. In October of 1972, the Central Pollution Control
Council presented an interim report on Methods for Long-Ranged
Setting of Permissible Automative Exhaust Limits. The report
concludes that the emission standard similar to the automotive
emission control of 1975 and 76 under "the U.S. Clean Air Act
Amendments" of 1970 should be enforced in Japan, in view of
serious air pollution in Japan, particularly in big cities.
Following the recommendation, the 1970 standards for
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maximum allowable emission from a p'assenger car were set at
2.1 g/kj£ of carbon monoxide, 0.25 g/kgpof hydrocarbon and
AM /
1.2 g/kg/of nitrogen oxides on the average emission, and
enforced from April of the same- year.
The 1976 standards for nitrogen oxides were to be even
tighter. In the recommendation mentioned above, the target of
maximum allowable amount was'to be 0.25 g/km on average for
those passenger cars produced after April of 1976. As a result
of technical evaluation, however, the recommendation presented
in December of 1974 by the Central Council for Control of
Environmental Pollution set the target year to achieve the above
mentioned standards as 1978. The revised standards are 0.6
for passenger cars of less than 1,000 kg in equivalent ^inertial
weight, and 0.85 g/km for passenger cars of over 1,000 kg on
average exhaust. It was decided to enforce the standards from
April of 1976 for new cars, from March of 1977 for cars of older
models and from March of 1978 for imported cars (refer to Table
5-1-1 for comparison between the 1975 standards and the 1976
standards).
Exhaust gas reduction effect of the standards is shown in
Fig. 5-1-1. As shown in the figure, the amount of carbon
monoxide, hydrocarbon and nitrogen oxides was reduced by 95$,
92$ -and 61$, respectively as the result of enforcement of the
1975 standards and the 1976 standards had an effect of reducing
the amount of emission of nitrogen oxides by 80$ from passenger
cars of less than 1,00(3 kg in, equivalent inertial1 weight and by
73$ from those of over 1,000 kg.
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122
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Pig. 5-1-1 Effect of Emission Standards for Automotive Exhaust Gas (passenger cars)
before Sept, 1966 (no control)
CO
50$
100$
Sept, 1966 (3$ standards)
Sept, 1969 (2.5$ standards)
45$ I April, 1973 (1973 standards)
April, 1975 (1975 standards)
before Sept, 1970 (no control)
HC
100$
Sept, 1970 (blow-by-gas standards)
59$ July, 1972 (fuel evaporation gas standards)
48$ I April, 1973'(1973 standards)
8$ April, 1975 (1975 standards)
NOx
before April, 1973 (no control)
100$
70$
April, 1973 (1973 standards)
39$ April, 1975 (1975 standards)
27$
_ April, 1976 (1976 standards) for those over 1,000kg
20$ | April, 1976 (1976 standards) for those less than 1,000kg
by Environment Agency
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Table 5-1-1 Allowable Limit in the 1976 Control & Reduction Rate
in Comparison to the 1976.Control
1. Nitrogen Oxides for Passenger Cars (New)
Method 1976 Control 1975 Control Reduction
Type of Automobile of "^ ~'. ~~ : 5a*e
measure- Allowable Average Allowable Average B-A
ment Limit (A) Limit (B) B z
Passenger Engines Cars with
cars with other less than
the capa- than 1,000 kg
city of 2-cycle in equi-
less than valent
10 pass- inertia!
engers weight 10-iaode 0.84 0.6 1.6 1.2 50
running (exclud- g/kg
on gaso- ing small
line or 4-cycle-
LPG engine
cars)
Cars with
more than
1,000 kg
in equi-
valent
inertia!
weight 1.2 0.85 1.6 1.2 29 %
(includ-
ing small
4-chcle
engine
cars)
2-cycle
engine
2. Hydrocarbon for Trucks (in use)
Type of Automobile Method of
Measurement
Trucks running on Idlinc
gasoline or LPG J-cuing
Type of Engine Allowable Limit
2-chcle engines
Special engines
Others
7,800 ppm
3,300 ppm
1,200 ppm
Special engines refer to engines witn special bulb, caburetter and
conbustion room.
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Vith respect to smaller cars with two-cycle engine, the
standards for carbon monoxide and hydrocarbon similar to those
for passenger cars with four-cycle engine were applied and the
standard for nitrogen oxides was set at 0.3 g/kg on average
emission in the 1975 standards.
However, as it is very difficult to reduce the emission
of hydrocarbon due to the structure in the case of two-cycle
engine, the target date has been postponed to September 30 of
1977. Meanwhile, an interim standards were set at 10-iaode
5.6 g/kg and 11-mode 33 g/test in Decmeber, 1975.
(2) Tightening of Emission Control of Nitrogen.Oxides
In the report of December, "1974, the Central Pollution
Control Council pointed out the necessity of facilitating
technological development, taking some measures in taxation,
and controlling automobile traffic, and the Automotive Exhaust
Gas Control Cabinet Council was established to study the matter
in January, 1975. As for tightening emission control of nitrogen
oxides from passenger cars, "Technical Discussion Group for
Reduction of Nitrogen Oxides from Cars" was established in
order to achieve the original target of standards. The group
is proceeding with technical evaluation and an interim report
was presented in December of 1975-
The report summarizes the results of the survey of the
state of technical development of the passenger car manufacturers
as of September, 1975. It explains about basic technologies to
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reduce emission of gas and summarizes the systems to be
adopted under the 1976 standards and the state of technological
development of the manufacturers with respect to the target
x
standards for nitrogen oxides" under the 1978 standards.
According to the report, thirty-four models of four
companies satisfied the, 1976 standards as of the end of November
and the other companies were to begin production from 1976.
The systems under the 1976 standards are:
(l) engine modification system: control of fuel supply system
and burning
(2) thermal reactor system: combination of engine modification
system, exhaust gas re-circulation device and thermal reactor,
(3) oxidation-catalyzing system: combination of engine modifi-
• cation system, exhaust gas re-circulation system and oxidation-
catalyzing system,
(4) stratification air supply burning system with subroom:
a subroom is attached to the combustion room of the engine
for stratification air supply combustion, and
(5) rotary engine system: combination of rotary engine, thermal
reactor and emission re-circulation system.
As for measure against exhaust gas after 1976, especially
measure to reduce emission of nitrogen oxides, the above system
are being improved, but all of the system still have problems in
durability, safety and reliability. The report says that it is
still too early to judge with which system the-target can be
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achieved. The manufacturers have been continuing the develop-
mental work and a considerable progress is recognizable.
Therefore, as each manufacturer makes progress in its develop-
mental work, a technical evaluation of such progress .will be
made.
In addition, the interim report mentions about economy of
fuel. According to the report, there has been a general tendency
of increasing fuel consumption due to the reduction of thermal
efficiency as a result of control of exhaust gas. Although the
comparison of the cars under the 1973 standards and those under
the 1975 standards disclosed an aggravation in the economy of
fuel, most of the cars under the 1976 standards showed an improve-
ment in the economy of fuel due to technological improvement,
in spite of the tighter control.
(5) Comparison with American Regulation of Exhaust Gas
In America, an epoch-making regulation of exhaust gas was
presented under the Federal Air Quality Act of 1970, and the
regulation has been revised due to the state of technological
development and the condition of energy resources since then.
Table 5-1-2 shows the comparison of present Japanese and
American standards for passenger cars. As there are some
differences in the method of measurement and enforcement, a
direct comparison is not necessarily appropriate. However,
the Japanese standards are tighter compared even with the
California standards, most tight in U.S.A., and considered to
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be most tough in the world.
Table 5-1-2 Comparison of Japanese and American Standards
for Automotive Exhaust Gas (passenger cars)
(g/km)
Pollutant Country
U.S.A.
CO California
Japan
U.S.A.
EC California
Japan
U.S.A.
KOx California
Japan
1973
24.2
24.2
18.4
2.11
1.99
2.94
1.86
1.86
2.18
1974
24.2
24.2
18.4
2.11
1.99
2.94
1.86
1.24
2.18
1975
9-3
5.6
2.1
0.93
0.56
0.25
1.93
1.24
1.2
1976
9.3
5-6
2.1
0.93
0.56
0.25
1.93
1.24
0.85
*0.6
"(Remarks) 1. by Environment Agency
2. fiscal year for Japan and calendar year for U.S.A.
3. Figures are average
4. *; The upper figure is for cars of more than 1,000 kg
in equivalent inertial weight and the lower figure for
cars of less than 1,000 kg
5. The method of measurement is 10-mode method of measure-
ment is 10-mode method of measurement in Japan and
LA-4C in 1973 and 1974 and LA-4CE after 1975 in U.S.A.
(4) Regulation of Exhaust Gaa for Trucks and Buses
The regulation of exhaust gas for heavy-duty trucks and
buses using gasoline or liquefied oil gas started with the
regulation of carbon monoxide in 1966, was gradually tightened
and the emission of hydrocarbon and nitrogen oxides was also placed
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tinder control in 1973 •
As or .light-duty trucks and buses, the standards similar
to those for passenger cars were applied until 1974* In the
1975 standards, however, the control was tightened as shown in
Table 5-1-1 and the emission of carbon monoxide, hydrocarbon
and nitrogen oxides was,reduced by 68/£, 44^ and 41^, respectively,
in comparison to that before the enforcement of the control.
As for new diesel cars running on light oil, the regulation
of black smoke was started in July, 1972. From September of 1974,
the emphasis was centered on nitrogen oxides and the emission of
carbon monoxide and hydrocarbon was placed under control.
In January of 1975, the regulation of black smoke for cars under
use, too, was started.
As for tightening control after 1976, the report of the
Central Pollution Control Council presented in December of 1974
recommends to promote the tightening of regulation of exhaust
gas for diesel-engine cars and small trucks excluded from the
1975 and 76 controls, and the special committee on automotive
pollution of the Central Pollution Control Council is studying
the matter now.
5.2 Control of Stationary Sources
As for establishment of standards for emission of nitrogen
oxides under the Air Pollution Control Law, an ordinance
(Ordinance No. 223, 1973) which revised part of the Enforcement
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Ordinance of the Air Pollution Control Law, with the establish-
ment of emission standards for nitrogen oxides as its main
content, and a Prime Minister's Office ordinance which partly
revised the Enforcement Regulations of the Air Pollution Control
Law were enacted and proclaimed on August 2, 1973> and enforced
on August 10 of the same year.
Nitrogen oxides are harmful by themselves only and moreover
substances from which photochemical oxidant is produced. The
control of nitorgen oxides is considered very urgent in order to
solve today's serious air pollution problem. "Therefore, the
environmental standards for nitrogen dioxide were established
as the first step in May 1973.
As for nitrogen oxides emitted from stationary sources the
environmental standards were established mainly for large boilers
from the standpoint of reducing emission of nitrogen oxides as
much as possible through utilization of available technology to
prevent emission of nitrogen oxides.
This enforcement of the emission control is the first step
to reduce the emission of nitorgen oxides from factories and
plants in order to achieve and maintain the environmental
standards. The philosophy in establishing the emission standards,
the main contents and the points requiring special attentions
of the ordinance and the Prime Minister's Office ordinance are
as follows:
l) On control system
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As for establishment of emission standards for nitrogen
oxides emitted as a result of burning under the Air Pollution
Control Law, it was originally planned to establish emission
standards considering nitrogen oxides as specific harmful sub-
stances under Provision 4 of Article 3 of the Law because there
was almost no technology to control production of nitrogen oxides
%
when nitrogen oxides were classified as harmful substances in
June, 1971• Since then, the technology to control production
of nitrogen oxides has been developed for practical use partly
through the improvement of burning system of large boilers.
And as it was judged that it would be more appropriate to adopt
the system of regulating emission concentration for controlling
the emission of nitrogen oxides produced in the process of
burning under Provision 3 of Sub-Section 2 of Section 3 of the
Law, that the condition of emission of nitrogen oxides widely
differs depending on each facility and that it is necessary to
set standards suitable for each type of facility taking into
consideration the characteristic of the facility, it was deter-
mined to set emission standards accordingly.
In adopting the system of controlling emission concentration,
it was decided to calculate the density of nitrogen oxides from
the amount of oxygen left in the exhaust gas in order to prevent
the malpractice of diluting the exhaust gas to satisfy the
emission standards.
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2) On facilities to be controlled
Facilities which, emit nitrogen oxides are boilers, various •
industrial furnaces, nitrate production facilities and so on.
It is urgently required to enforce an emission control, especially
for (i) those which emit a large amout of nitrogen oxides and
(ii) those which emit nitrogen oxides of high density among the
above facilities. This time it was decided, however, to establish
the emission standards for boilers and nitrate-production facilities
for which the control technologies were already available and
heating furnaces to which the control technologies of boilers
could be applied. As for boilers and heating furnaces, only
large facilities were included for control in view of the available
control technologies.
"3) On emission standards
It was decided to take into consideration that the present
density of emission can be reduced by 30 to 40 percent by adopting
the two-stage combustion system, exhaust gas recirculation system
or improving burner with respect to boiler and that some degree
of improvement can* be expected through adoption of those techno-
logies with respect to heating furnaces, in establishing emission
standards. In addition, it was decided to establish separate
emission standards for facilities in use due to difficulty of
remodeling=.
As for boilers, the fact that the condition of emission
widely differs depending on- type of fuel used was taken into
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consideration-.
As for nitrate production facilities, it was decided to
establish emission standards on the assumption that the smoke
eliminating efficiency of smoke eliminating device is about
90 percent.
In addition, an ordinance (Ordinance No. 349» 1975) which
partly revised the Enforcement Ordinance of the Air Pollution
Control Law and a Prime Minister's Office ordinance (Prime
Minister's Office Ordinance No. 75, 1975) which partly revised
the Enforcement Regulations of the Air Pollution Control Law
were enacted and proclained on Decraeber 9, 1975 and enforced on
December 10 of the same year.
Although the emission standards for nitrogen oxides were
established in August, 1973, the application of the standards
has been extended and the emission standards have been made
toughter later, in view of technological development since then.
The purpose of revision was to facilitate a further reduction of
emission of nitrogen oxides from factories and plants in order
to achieve and maintain the environmental standards for nitrogen
dioxide. The philosophy, the main contents and points requiring
special attensions of the ordinance and the Prime Minister's
Office ordinance are as mentioned below.
l) Background for tightening of control
As for nitrogen oxides, it has been decided to achieve the
environmental standards in the regions with five-year allowance
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and the interim target in the regions with eight-year allowance
by May, 1978. The review of the condition of air pollution in
1974 showed, however, that it would be fairly difficult to achieve
the targets and it is, therefore, strongly desired to make positive
progress in the control of air pollution by nitrogen oxides.
As .for measures to reduce emission of nitrogen oxides from
stationary sources, improvement of stack gas denitration technique
and combustion system and switch of fuel can be mentioned.
At present, the stack gas denitration technique is available for
practical use for exhaust gases like LNG which contain neither
sulfuric oxides nor soot and dust. As for exhaust gases from
heavy oil, too, a large stack gas denitration facility is being
used in some cases, and it seems that such facility will be
developed for practical use within one year or so. However, the
stage has not been reached yet to establish standards equally
applicable nationwide. As for switch of fuel, there is a limita-
tion as to supply of fuels because there is no plan to supply
fuels with less nitrogen. It was decided, therefore, to concentrate
the tightening of control on improvement of combustion system and
partial switch of fuels.
2) On facilities to be controlled
As facilities which emit nitrogen oxides, there are boilers
already under control, metal heating furnaces, oil heating furnaces
and nitrate production facilities as well as cement incinerators,
coke ovens, sintering furnaces, and glass melting furnaces.
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In tightening the emission standards, it was decided to newly
include cement incinerators and coke ovens (only new ones) for
control. As it was recognized that the emission of nitrogen
/
oxides can be reduced with both types of facilities if specific
types of furnaces are used,'it was decided to include them for
control.
As for sintering furnaces and glass melting furnaces, the
stack gas denitration technique will be, it seems, mainly used
as a measure to reduce emission of nitrogen oxides. In this
revision, it was decided not to include them for control,
because it is still not certain when such technique can be
developed for practical use.
Additionally, in view of the progress in the technology to
reduce emission of nitrogen oxides after the establishment of
the emission standards for nitrogen oxides in August of 1973»
it was decided to extend its application to boilers, metal heating
furnaces and oil heating furnaces of up to 10,000 Nm /h of
exhaust gas.
3) On emission standards
In tightening the emission standards, improvement of burning
system and partial switch of fuels were considered as prerequisite
conditions. As for metal heating furnaces and oil heating furnaces,
the emission standards were established on the assumption that
some of them may require stack gas denitration. As for facilities
already built, separate emission standards were established
because it will be difficult to remodel them.
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6. Future direction of measures against photochemical smog
The Promotion Conference prepared a following recommendation
as to the future direction of.measures against photochemical smog
and agreed that the recommendation should be utilized when the
agencies and ministries conc'erned plan or execute various measures.
Photochemical smog ia occurring frequently in the large
cities and their surrounding areas mainly in Summer, creating
serious social problems. The Government established "the Photo-
Chemical Smog Control Promotion Conference" in July of 1972 to
promote a close communication among the administrative agencies
concerned with counterineasures against photochemical smog, and
comprehensive and effective measures, and has been carrying out
various studies and measures following "On promotion of measures
against photochemical smog" decided by the Conference on July 15,
1972.
The occurrence mechanism and effect of photochemical smog
have been partly discovered both qualitatively and quantitatively
through the three-year comprehensive study started in 1972 and
carried out in Tokyo Bay and Osaka Bay areas and various basic
studies by the research institutions, but still further studies
on the effects on living things of photochemical smog are urgently
required. Together with promotion of basic studies, comprehensive
and strong measures against stationary and mobile sources should
be promoted in order to achieve the environmental standards for
nitrogen dioxide and'photochemical ozidant and those for hydrocarbon
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to be established soon within the target date for thorough
prevention of photochemical smog.
As a measure against nitrogen oxides from stationary
sources, an emission control was started aa to large boilers
in 1973• A further effort should be made for development of
technology to control emission of nitrogen'oxides and the appli-
cation of the emission standards should be extended to other
types of facilities.
At the same time, a calculating technique for maximum
allowable emission in a region should be examined for early
introduction of a control of total amount.
As measures against hydrocarbon from stationary sources,
various measures such as a guidance to adopt the floating roof
system, already in use, in building large tanks for crude oil
should be taken and at the same time it is necessary to develop
detailed and effective measures, paying attentions to diversifica-
tion of sources.
As for measures against hydrocarbon and nitrogen oxides
from mobile sources, the control of new cars running on gasoline
or liquefied oil gas was drastically tightened both in 1974 and
1975. In addition, the 1976 control of nitrogen oxides was
determined. However, the pollution due to concentration of
automobiles in the large cities cannot be overlooked and it is
necessary to tighten the control of automobiles including small
trucks and diesel-engine cars. In addition, the improvement of
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roads and urban structure should be studied as a part of long-
range plan, and for a time being, a measure to reduce automobile
traffic should be promoted as a part of the comprehensive traffice
control in the large cities.
As health measures, informations on photochemical smog should
be thoroughly disseminated to schools and the general public.
Especially in the regions where there is a high possibility of
photochemical smog occurring, measures such as instruction in
emergency measures should be taken to keep damages at minimum.
In addition, the accuracy of forecast in the preceding day
should be improved in order to make emergency measures more
effective. .Also, photochemical-smog should be prevented through
effective control of sources such as voluntary control of use of
automobile.
In order to prevent photochemical smog, the measures mentioned
above and a comprehensive measure based on the execution plan
described in the following should be promoted. By so doing,
healthy and cultural living environment for the people will be
secured.
Execution Plan
I. Preventive Measures
1. Establishment of environmental standards
Environmental standards for hydrocarbon which causes photo-
chemical oxidant should be immediately established, taking into
consideration the occurrence mechanism of photochemical oxidant.
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2. Measures against stationary sources
l) Measures against nitrogen oxides
(l) Together with extension of the emission control of nitrogen
oxides and tightening of %he emission standards, the develop-
ment of technologies to -control emission of nitrogen oxides
from stationary sources and those such-as a stack gas denitra-
tion technique to eliminate them should be facilitated.
(2) As for nitrogen oxides, studies and research works including
development of air pollution forecasting technique should be
carried out for early introduction of the control of total
emission.
2) Measures against hydrocarbon
(l) As for hydrocarbon from stationary sources, comprehensive
and rational measures should be examined such as switch of
raw materials and measures against secondary pollution, taking
into consideration safety and efficiency, and measures which
can be carried out should be gradually executed only with
respect to large-scale hydrocarbon emitting facilities and
organic solvents which are photochemically highly reactive
and also being used in large quantities, in view of the fact
that it is difficult to enforce a standard control due to
diversity of hydrocarbon emitting sources.
(2) In order to prevent leakage of hydrocarbon in the process
of oil refinery, distribution and selling, studies on the
development of hydrocarbon processing system and surveys of
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emission of hydrocarbon from various devices should be
carried out.
(3). A hydrocarbon eliminating device of high efficiency should
be developed.
3) Emergency measures
In order to establish emergency measure's against photo-
chemical oxidant, techniques to forecast high density pollution
by photochemical oxidant and rational preventive measures should
be developed.
3- Measures against mobile sources
l) Measures against automotive exhaust gas
(l) As the contribution of small trucks and diesel-engine cars
to air pollution is not small, the control of exhaust gas
from these types of automobiles should be tightened as early
as possible.
(2) The control of exhaust hydrocarbon for trucks should be newly
enforced among automobiles running on gasoline or liquefied
oil gas in use.
(3) As for automobiles of 1975 models, the control of automotive
exhaust gas should be considerably tightened and at the same
time, the development of preventive technology should be
speeded up in order to enforce the control of emission of
nitrogen oxides with respect to 1976 models.
(4) Together with tightening of the control of exhaust gas,
measures should be taken to make sure through inspection and
58
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servicing of automotive exhaust gas cleaning 'device and
other devices. At the same time, automobiles poorly serviced
should be strictly controlled.
(5) Works to develop automotive exhaust gas controlling techniques
should be assisted and promoted.
2) Measures against automobile traffic
(l) For reduction'of automobile traffic in the large cities, optimum
control of flow of traffic and rational allocation of
available road space, various measures such as expansion of
road for pedestrians, non-parking area and road exclusively
for buses, construction of road exclusively for bicycles and
improvement of automatic traffic control system should be
carried out.
(2) The transportation capacity and passenger service of public
transportation facilities such as bus, subway and railway
should be improved and the use of such facilities should be
promoted,and arrangement of mono-rail or other hew traffic
system should be studied. At the same time, reorganization
of bus routes, adoption of mini-bus, introduction of bus location
system and traffic control system giving priority to buses should
be facilitated.
(3) For efficient freight transportation in the cities, establish-
ment of common distribution system and truck terminals should
be promoted.
(4) Studies on the control to prevent emergency and the method
of guidance at emergency should be carried out. ,A traffic
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control system and the way to execute such control should
be studied.
3) .Measures with respect to composition of gasoline
(l) An administrative guidance should be contiriued in order
to prevent increase of hydrocarbon in gasoline which is
photocheiaically highly reactive.
(2) A study on the correlation between the composition of
gasoline and photochemical reaction should be continued.
4» Rationalization of urban structures
l) Execution of surveys of air pollutions of urban type
In order to develop effective preventive measures against
urban type air pollution, a comprehensive survey should be
executed to find out the relationship between various activities
and air pollution in the large cities. At the same time,
measures to induce activities desirable from the Standpoint
of preventing air pollution in the large cities should be
examined.
2) Measures with respect to roads
(l) For efficient use of roads and smooth flow of road traffic,
improvement of urban structures such as improvement of sub-
urban center and distribution system should be carried out.
At the same time, bypass roads should be constructed in order
to reduce traffic passing through the central part of the
city.
(2) For smooth flow of traffic and prevention of air pollution
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due to traffic congestion in the central part of the city,
the existing roads should be improved through such measures
as expansion of roads and construction of flyover roadways.
Together with rationalization of traffic, and maintenance
and promotion of urban functions, establishment of new
. t
traffic system should be examined in. order to reduce
traffic congestion.
II Surveys and Studies
1. Surveys and studies
l) Survey of actual conditions with respect to photochemical smog
With respect to photochemical smog, a comprehensive
survey covering a wide area with air pollution due to photo-
chemical reaction was carried out in the Osaka Bay area in 1974-
In addition, a correlation between environmental conditions
and health damages was studied both in the Osaka Bay and
Tokyo Bay areas.
As the result of the past surveys, the conditions of air
pollution, flowing of pollutants, photochemical reaction
characteristic of substances causing photochemical smog and
the occurrence mechanism of photochemical smog are understood
better now. Qn the basis of the results of the past surveys,
it has become possible to develop a technique to forecast
photochemical smog.
2) Future surveys of actual conditions of photochemical smog
(l) In 1975, special regular weather observations will be done
61
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for issuing emergency warnings of high accuracy and data
thus obtained will be supplied to the local authorities
to help them in issuing emergency warnings. At the same
time, together with development of photochemical smog fore-
casting technique in order to make possible establishing
an effective controlling measure a day. earlier, a way should
be found to improve the efficiency of emergency measures.
(2) On the basis of the results of the comprehensive surveys of
actual conditions of air pollution due to photochemical
reaction, measures against air pollution in a wider area should
be developed through statistical analysis of the data.
(3) Humid air pollution including the phenomenon of acid rain
which is considered to be produced through a complex mechanism
somewhat similar to that which produces photochemical smog
should be investigated.
(4) The relationship between the symptoms and the environmental
conditions such as concentration of oxidant should be investigated
and analyzed with respect to the cases suffered from photo-
chemical smog in the Tokyo Bay, Osaka Bay and Setonaikai areas.
(5) As for nitrogen oxides and hydrocarbon which cause photochemical
smog, the relationship between the quantity of emission and
fuel, burning condition or burning facility should be
investigated.
(6) As s part of the system of monitoring air pollution due to
photochemical reaction, standards for selection of indicator
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for issuing emergency warnings of high accuracy and data
thus obtained will be supplied to the local authorities
to help them in issuing emergency warnings. At the same
time, together with development of photochemical smog fore-
casting technique in order to make possible establishing
an effective controlling measure a day. earlier, a way should
be found to improve the efficiency of emergency measures.
(2) On the basis of the results of the comprehensive surveys of
actual conditions of air pollution due to photochemical
reaction, measures against air pollution in a wider area should
be developed through statistical analysis of the data.
(3) Humid air pollution including the phenomenon of acid rain
which is considered to be produced through a complex mechanism
•somewhat similar to that which produces photochemical smog
should be investigated.
(4) The relationship between the symptoms and the environmental
conditions such as concentration of oxidant should be investigated
and analyzed with respect to the cases suffered from photo-
chemical smog in the Tokyo Bay, Osaka Bay and Setonaikai areas.
(5) As for nitrogen oxides and hydrocarbon which cause photochemical
smog, the relationship between the quantity of emission and
fuel, burning condition or burning facility should be
investigated.
(6) As s part of the system of monitoring air pollution due to
photochemical reaction, standards for selection of indicator
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plants and judgement of effect should be established and
at the same time, the effect on plants should be investigated
in order to obtain basic information concerning the necessity
of establishing living environmental standards for air pollu-
tants.
Experimental studies
In order to find out the mechanism of photochemical reaction
and the effects of pollutants on plants, the following experimental
studies should be carried with the national research institutes
taking the initiative.
l) Studies concerning air pollution measuring techniques
In order to define and evaluate the occurrence, dispersion
and effect on living things of photochemical smog, a technique
of microanalysis for harmful gases and a quick physico-chemical
measuring technique for photochemical aerosol should be developed
and improved. At the same time, studies necessary for standardi-
zation of correction method should be carried out with respect
to measuring technique for harmful gases and suspended particulate
matters.
,In addition, in order to quickly find out weather factors
contributing to development of photochemical smog, a remote
measuring technique for atmospheric physical phenomenon should
be developed.
2) Investigation into mechanism of photochemical reaction
In order to define the occurrence mechanism of air pollution
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due to photochemical reaction, a survey of condition of
emission of hydrocarbon and acid particulate matters in the
photochemical aerosol should be done and physico-chemical
analysis of those substance should be done. Also, the produc-
tion mechanism of secondary-pollutants produced by photochemical
reaction should be investigated.
3) Investigation into effect on living things
In order to find out about chronic and combined effects
among various effects of photochemical smog on living things,
the effects of oaone and nitrogen ozides on living things
(animals) should be studied.
Is for effects on plants, sensitivity and tolerance limit
of agricultural products and trees to pollutants should be
clearly defined and evaluation of indication characteristic and
mechanism of damaging should be carried out.
Ill Establishment of Forecasting, Monitoring and Measuring System
1. Establishment of forecasting system
l) In order to strengthen the system of forecasting air pollu-
tion, an air pollution.weather center should be established
and weather informations should be supplied to local autho-
rities to assist them in carrying out measures against air
pollution. In 1975» an air pollution weather center will be
established in Takamatsu.
2) For prompt supply of weather informations, an information
supply system will be established.
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2. Establishment of monitoring and measuring system
The national air measuring network will be improved and
at the same time, an assistance will be extended to local
s
authorities in providing recorders for automatic measurement
of nitrogen oxides, oxidant-and hydrocarbon, telemeter systems
and monitoring telemeter system.
3. Standardization of method of measurement
Following establishment of the environmental standards for
hydrocarbon, the method of measuring hydrocarbon in the air will
be standardized. In addition, the method of measuring photo-
chemical oxidant and nitrogen oxides will be examined for
improvement.
IV. Health measures
1. Investigation into the relationship between health damages and
environmental conditions
In order to find out about the details of the reports of
health damages due to, it appears, photochemical smog and define
the relationship between environmental conditions such as the
density of oxidant and health damages, surveys of actual conditions
will be carried out in the Tokyo Bay, Osaka Bay, and Setonaikai
areas.
2. Promotion of health measures at medical institutions
Under a close cooperation with public health centers,
national hospitals, medical institutions and doctors' associations,
the actual conditions of damages should be found and treatment
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and recuperation should be thoroughly managed.
3« School health measures
l) Informations on photochemical smog should be disseminated at
schools and a guidance should, be given for emergency procedures.
2) As for the special project to improve health, mobile classes
will be continued. At the same time, educational environment
for improvement of health of school children should be provided,
together with expansion of special health examination and school
environment greening works should be carried out.
3) Double windows and air cleaning equipment should be provided
at schools for which such necessity has been recognized due to
air pollution.
4. Measures for general public
Informations on photochemical smog should be thoroughly dis-
seminated. An instruction on emergency measures should be given
and efforts should be made to find out the actual conditions of
health damages.
5. Health measures at working places
Actual conditions of health damages of workers should be
found out. Necessary administrative guidance as to provision
of eye washing facility for emergency and close cooperation with
medical institutions should be given.
66
149
-------
V. International Cooperation
1. The Mr Management Sector Group of OSCD has set up a special
committee at the proposal of Japan and the committee has been
discussing the problems of photochemical air 'pollution. Japan
has been actively participating in the study and should promote
a further international cooperation.
2. Japan should promote exchange of informations with America
which has much experience in the study of photochemical smog,
and dispatch delegations to America to promote cooperation in
research works between two countries.
67
150
-------
EXPERIMENTAL RESULTS OF MOBILE SMOG CHAMBER
(Air Quality Bureau-Environment Agency)
Japanese Delegation
1. Construction of Mobile Smog Chamber
1.1 Object of Construction
To promote the countemeasures against air pollution caused by photochemical
reaction, the mecahnism of generation of the pollution should be clarified.
Hence, in addition to the basic laboratory study the field investigation should
be carried out also.
The Environment Agency has a mobile smog chamber constructed in 1971 with
reserve funds, ¥95,037,000, to start this investigation in the field in the
photochemical smog season of 1972.
The mobile smog chamber comprises a photochemical smog chamber vehicle
loaded with the photochemical reactor (smog chamber and ultra-violet irradiation
apparatus), and a chemical analysis vehicle loaded with various instruments that
measure precursor and secondary products generated by the photochemical reaction.
The mobile smog chamber was manufactured by the Shimazu Manufacturing CO., Ltd.
This mobile smog chamber will be'sent to various places, introducing ambient
air into the chamber, irradiating the air by ultra-violet light to generate
photochemical reaction, and investigating in detail the conditions of pollutants
before and after the reaction to facilitate the establishment of real counter-
measures against photochemical air pollution.
151
-------
1.2 Basic Principles of the Chamber Experiment.
It was assumed that the photochemical air pollution occurring in Japn is
similar to that observed in Los Angeles, that is, oxides of nitrogen, hydrocarbons,
etc., discharged from stationary and mobile sources induce'photochemical reactions
by the energy of ultra-violet light in the solar radiation to generate the
secondary products represented by oxidants. The outline of this emission mechanism
may be simply illustrated as shown in Fig. 1.2.1.
The experimental system is constructed to measure first the concentration
of pollutants in the air sampled into the smog chamber in the field, then irradi-
ated by use of ultra-violet lamps instead of sunlight to produce photochemical
reaction, and then to measure the concentration of reaction products by various
instruments mounted on the analysis vehicle.
Fig. 1.2.2 is a flow diagram showing the process of the introduction of
ambient air for the production of photochemical reaction and the measurement of
the secondary products.
°2 .
(1) Dissociation cycle of N02 (2) Interaction of hydrocarbon and N02 ~ad
photo-dissociation
Fig. 1-2-1 Forming reaction of 0
152
-------
1.3 Photochemical Smog Chamber Vehicle
1.3.1 Construction
The photochemical smog chamber vehicle (hereinafter referred to as "chamber
vehicle") is equipped with apparatus that samples ambient air Into the smog
chamber, and applies the irradiation of ultra-violet light to produce photochemical
reaction. The sample gas within the smog chamber is sent to the photochemical
reaction analyzing vehicle, through a docking device, for analysis.
The chamber vehicle is constituted from the components (1) to (10):
(1) Vehicle
This is a large-sized bus modified to load various instruments and apparatus.
Its dimensions are as follows:
length:'8.73 m; width: 2.43 m; hieght: 3.35 m.
measurement of meterological
conditions
,--___
1 ^r air sampling pj
air ssdplina/ri ^7 lamp
devices, \^U r^=~~^
i
i
U7 lizht intensity '
temperature tuning,
system i '
control system '
i
•^
>smog \
-J^haabj*
J i — ,<
~j s
j r —
i
i
i
i
•
>?kin(
^tem
I
1
u
•p instruments
. JL data pro<
— l h~
• J H1 '
control part* 1
eye irritation i
devices
1
essing system
is
leasuring
photochemical smog chamber
vehicle
photochemical smog analyzing vehicle
Fig. 1.2.2 Flow Sheet
153
-------
(2) Air sampling apparatus
This is to sample ambient air into the smog chamber comprising an air
sampling pipe and an air sampling blower of at least 0.5 m /min flow rate. The
air sampling pipe is an aluminum pipe with the inner wall coated with Teflon and
it is variable in length from 1 to 10 m above the ground.
(3) Smog chamber
This is a cylindrical chamber made of pyrex glass that adsorbs little
pollutants. 2 m of the ambient air is sampled into this chamber to be subject
to the irradiation of ultra-violet light in order to induce the photochemical
reaction within the chamber. This smog chamber is hung from a frame so as to
withstand the oscillation and shock of automobile during travelling. It can be
drawn from the irradiation room on rails (with the frame), and may be removed
from the frame.
The upper portion of the smog chamber is provided with two holes, through
which two glass shafts extend respectively to agitate the interior of the
temperature control
system
f©D$ X
commercial electfic
power supply
/
cm
>3
pressuring, evacuasting
system
dockic
dyna
generator system
switch board and control panel
8.730
stabilizer for
TJV lamp
UV lamp
air ssapling system
Pig, 1.3*1 Arrangements of appartuses in th.e chamber vehicle
154
-------
chamber with glass propeller fan mounted on the end of the shaft. Further, to
permit experiments under vacuum of less than about 8 mm Hg. and pressurized
conditions of 0.1 kg/cm the smog chamber is air tight. Packing and the like
surfaces in contact with sample gas within the chamber are all made of Teflon or
Teflon coated materials except for Pyrex glass.
(4) Ultra-violet irradiation apparatus and measuring and recording apparatus.
The rear portion of the vehicle is provided with an ultra-violet irradiation
room which is kept warm with insulating materials. The smog chamber is installed
at the center of the room and surrrounded by 96 ultra-violet lamps. An alumium
electropolished reflector is mounted on the back of each lamp to provide high
reflection.
The intensity of ultra-violet lamps may be controlled and its spectrum may
be adjusted by a combination of the following three types of lamps:
FL40SB-A (with output peak approximately at 420 nm)
FLR40SBL-A (with output peak approximately at 365 nm)
FLR40SE-A (with output peak approximately at 310 nm)
The energy of ultra-violet light irradiated into the smog chamber is usually
measured near the outer wall of the smog chamber so as to keep its intensity
constant during the irradiation against the temperature change in the irradiation
room and voltage variation. If the intensity of the irradiation if further
varied, a manual regulator is provided to maintain constant intensity.
155
-------
(5) Temperature control
Since the photochemical reaction scheme and reaction speed are affected by
temperature, the temperature within the smog chamber should be controlled.
Such control is accomplished by insulating the whole irradiation room and
is insured through use of temperature sensors spaced throughout the irradiation
room. Temperature control is effected by manual heating and manual and/or
automatic cooling.
(6) Pressure regulator
The sample gas within the smog chamber is continuously or intermittently
sent through the docking device to the analyzing vehicle to measure its constitu-
ents. The volume of the sample gas within the smog chamber is then reduced.
air sampling pipe
air sampling pump
vacuum pump
-G—-
pressure control
XX
standard air
J±g. 1.3-2
pressurizing. pump
UV lamps
IT
TT
irradiation
Smog chambers
(Pyrex glass)
' 111
UV lamps
' f
to measuring vehicle
from measuring vehicle
of the chamber Tehiole
156
-------
Hence this regulator is provided to supplement from a cylinder the same amount
of purified air as that of gas sent to the analyzing vehicle. The reference gas
is supplemented through a valve that is automatically opened upon the reduction
of gas pressure to -6mm H20 within the smog chamber because of the supply of the
sample gas.
(7) Booster
Ambient air is generally sampled into the chamber by a sampling blower.
Otherwise air can be sampled by evacuating the smog chamber to open valve.
Further, a pressure-sensitive device is provided to raise the pressure within
2
the smog chamber to 0.1 kg/cm after air sampling. A pressure-reducing device
is constructed from a mechanical booster and a conventional vacuum pump to be
used for sampling under vacuum and, in addition, mainly for vacuum cleaning of
the inner wall of the smog chamber before and after each experiment.
(8) Docking device
This is a connecting pipe to transfer sample gas from the smog chamber to
the instruments on the analyzing vehicle or to return the gas to the chamber,
the pipe being made of teflon coated with heat insulator.
(9) Self-power supply
In the experiment a commercial power supply (200V, 3 phase, 50 cycle and
BOA) is mainly used, while an engine generator (200V, 3 phase, 50 cycle and 10.4
kW) is carried as self-power supply.
(10). Others
A control panel is provided to gather into one section the various instruments
and controls for controlling the irradiation intensity and temperature during
measurement.
157
-------
T.4 Photochemical smog analyzing vehicle
1.4.1 Constitution
The photochemical smog analyzing vehicle (hereinafter referred to as the
analyzing vehicle) is loaded with instruments to analyze the"sample gas supplied
from the smog chamber, and apparatus to observe meteorological factors.
The analyzing vehicle is constituted from the following items (1) to (7):
Location of each apparatus within the analyzing vehicle, flow diagram, etc.
are shown in Figs. 1.4.1 and 1.4.2 and Table 1.4.1.
(1) Vehicle
The vehicle is a modification of a large-size bus to load various instruments,
etc. Its dimensions are as follows; length; 11.40 m, width; 2.49 m, height;
3.42 m,
(2) Air sampling device
While the analyzing vehicle generally analyzes the sample gas from the
chamber vehicle it may travel alone as an air pollution analyzing vehicle to
measure ambient air with the air sampling device. The air sampling device
comprises a stainless steel pipe with the inner wall coated with Teflon and is
variable in height to extend from 3.5 to 10 m above the ground.
(3) Instruments and recorders
The instruments listed in Table 3.4.1 were selected after due consider to
the requirements that (1) they shall be prevented from any damages and errors
caused by oscillation. (2) they shall have high performance to sense small
concentration changes caused by photochemical reaction, (3) they shall have
158
-------
Wind direction, Wind velocity Jtocking device
Temperature, Temperature \ 03 meter
Ultraviolet ray meter X L met
/ Nitric acid meter \ / | /
Suspended
Unit : on
perticles
meter
rrfn/cxr—
SQ"3 — D
5 U ^4.^
D 1
II(DD
1
Hydroc.
Switch
»
£?/£vj
1
,
1
Bomb chamber /
i\ i
1
1
^
irbon meter f Measurement control panel
board Sulfulic acid meter
/
Entrance Motor
•External pow<
<;
f
1
H \
Sink
Test bench
[
Air conditioner
1 >•
1 Typewriter \ Test bench
Data logger GAS chronograph
it source
_ 11 Ann s»
\
0
9>
I
Fig. 1-4-1 Arrengements of apparatuses in the Analysis Car
Wind direction,j~>00
velocity
Temperature,
humidity
Quantity of|
ultraviolet rays
Quantity of visible
rays of beam |
h->04
CO
Total hydrocarbon.
methane, CO I
SO?
NO
NO
Dust
Gas
chronograph
Eye irritation
00— 9
01~*
02—?
03— *
04~*
05—*
06--*
07—*
08—5
09—3-
o
H
n
(0
>t
(D
to
rr
5"
09
0.
19
O
n
•Exhaust port
Fig. 1-4-2 Flow sheet for photochemical smog;analysis car
159
-------
rapid response speed to permit intermittent measurement, (4) the consumption of
sample gas shall be small.
Major instruments can continuously and intermittently measure the constituents
and others can intermittently measure the costituents by automatic switch-over
apparatus.
(4) Data processing system
This system types out the data measured by each instrument with a required
interval of time.
(5) Eye irritation monitoring device
This is a device to expose eyes to the sample gas to observe the eye irrita-
tion symptoms as the effect of secondary products formed by photochemcial reaction.
(6) Self-power supply
In the investigation, commercial power supply (200V, single phase, 50 cycle
and 50A) is mainly used, while an engine generator (100V, single phase, 50 cycle
and 10.4 kW) is loaded as self-power supply. Further, the voltage of the commer-
cial power supply is changed from 200 to 100V by a transformer provided in the
vehicle to operate each apparatus.
(7) Others
A cooler and a heater are loaded to reduce the errors of measured data due
to the abrupt change of temperature and improve the temperature condition within
the vehicle.
Also work tables, sink, etc. are provided to permit manual analysis and
measurement within the vehicle.
leo
-------
Table 1.4»1 Instruments in the Photochemical Smog Measuring Vehicle
CTl
Measuring Item
CO
Hydrocarbon
(THC, CH4)
NO' and NO
-------
Table 1«4«1 Instruments in the Photochemical Smog Measuring Vehicle (Cont'd.)
10
Measuring Item
Light Intensity
(total)
UV light Inten-
sity (spectral
distribution)
Hydrocarbon
(component)
NO and N02
Manufacturer
Suga Shikenki Co.,
Ltd.
Japan Spectroscopic
Co., Ltd.
Shimazu Seisakujo
Co., Ltd.
Denki Kagaku Keiki
Co., Ltd.
Instrument
Integrator irradi-
ance Recorder
UV spectrograph
Gas chromatograph
Nitrogen Oxides
Automatic monitor
Catalog No. Method
PH-11P2
UV-55 -
GC-4BMPFE
GP-5 Saltzman
method
Measuring Range
UV 300-400 nm
Visible 400-700 nm
300-500 nm
10 nm interval .
0 - 0.25,
0.5, 1 ppm
-------
2. Performance Test of Smog Chamber
2.1 Outline
One of the essential points in the use of the chamber is to make the
condition within the chamber approach the atmospheric one as close as possible.
Accordingly, it is necessary to know whether or not the condition of the chamber
to be used is close to that of the atmosphere. To this end, the rate of loss of
NO and 0«, and the time required to homogenize air within the chamber were
A w
investigated.
2.2 Rate of loss of NO, NO,, and 0., in the chamber
3
The inside volume and surface area of this smog chamber are 2.1 m and 10
2 -1
m respectively. The ratio S/N (surface area/volume) is 5 m . That ratio of
the smog chamber is much smaller than that of the existing immobile chambers.
To investigate surface effects upon the relatively reactive NO, NOp and 0^, the
rate-of-loss measurements were carried out with and without light and with and
without agitation, and rate of decrease (hereinfater referred to as R.D.) of
each component was determined.
Further, in the supplement of clean air for analysis into the chamber, the
relationship between the dilution and gas concentration change within the chamber
is expressed as follows:
* C
-V
dt =
o
Co
dc
(2.21)
163
-------
where C : gas concentration (ppm) after t hours
Co : initial gas concentration (ppm)
C1 : gas concentration (ppm) in diluted air
2
Vo : volume of chamber (2.1 m )
V : amount of air to be supplemented per unit time (&
s
The correction for dilution was made by the above equation.
(1) Loss of NO
After the chamber was filled with clean nitrogen, 0.6£ of a 1670-ppm-NO-in-
N2 mixture was introduced directly into the chamber through the regulator with
flow meter, and left for 2.5 hours with the initial concentration of NO of
A
0.567 ppm, and NO of 0.502 ppm as measured by chemiluminescence NO meter without
A
irradiation and agitation.
Also similar experiment was carried out in which NO sample was left for 2
hours with agitation and without irradiation.
In both experiments, it was found that R.D. of NO is low in the order of
less than 1.1%/hr. while there is little oxidation to N02> so that th loss of NO
was found to be negligible if no irradiation was conducted.
(2) Loss of N02
In the same way as the above-mentioned adsorption experiment of NO, about 1
liter of a 906-ppm-N02-in-N2 mixture was introduced into the chamber, and
maintained with the initial concentration of NO. 0.625 ppm, and NO, 0.155 ppm,
A
without agitation and irradiation.
The R.D. of N02 in the order of 2.3%/hr. Also similar experiment was
carried out in which N02 sample was left for 2.5 hours darkness with agitation.
164
-------
It is presumed for the present from these results of the experiments that
the loss of NC>2 on the surface of the chamber is scarce. However, since this
measurement of NC>2 was carried out by chemiluminescence system its concentration
was represented by NO-NO.
X
(3) Loss of 03
The chamber"was filled with clean air and the air was charged with 03 from
0- generator, then the 0, was left for 2.5 hours with its initial concentration
of 0.697 ppm under darkness weith agitation.
R.D. in tis case seemed to be rather high in the order of 8.8%/hr. Also
similar experiment was carried out without agitation. The latter was in the
order of 6.6%/hr, being slightly lower than that with agitation. It is noted
that both experiments showed relatively high R.D. in the order of over 6.6%/hr.
Further, when the loss of 03 was examined under irradiation (initial
cncentrations of 0,; 0.215 ppm in air), R.D. was found to be 21%/hr. THe change
and loss of 03 is considered very large even if the effect of purities in the
balance air was taken into consideration.
The above-mentioned results are shown in Table 2.1.1.
The examination of the surface effect of the chamber, i.e., one of the
basic characteristics of the smog chamber, resulted in a presumption that R.D.
of both NO and N02 were negligible under .no matter whether agitation is employed
or not.
Referring to 03, 6.6%/hr. of R.D.was shown even under dark without agitation.
Further 8.8%/hr and 21%/hr of increased R.D. were noted respectively with agitation
and under irradiation with agitation. This showed that the 03 in the chamber
has some problems.
165
-------
Table 2.1.2 R.D. of NO, N02 and
in
N2
in
air
dark
dark
irradi-
ation
NO N02 03
with -1.1%/hr -4.6%/hr %/hr
agitation
without -1.0 -1.6
agitation
with -1.5 -2.3 -8.8
agitation
without -0.7 -0.7 -6.6
agitation
with -21.0
agitation
Experimental Condtions:
Temperature: 20 * 25°C
Humidity: less than 30%
Intensity of ultra-violet light: 9.5 mW/CM2
2.3 Measurement of ultra-violet irradiation intensity
2.3.1 Method based on photodissociation speed of N02 (K, value)
166
-------
(1) Outline
It is impossible because of the complexity of the shape, reflection factor,
transmission factor, effective light path, etc. of the chamber to accurately
measure the quantity of light contributing to the photochemical reaction in the
chamber by means of conventional actinometer. As a method that overcomes these
difficulties, there is frequently used the method of estimating the intensity of
light by the use of photodissociation reaction of N02 in N«.
The primary quantum yield in the photodissociation of N(L is close to 1
within the spectrum range associated with photochemical air pollution. Low
concentration N02 is photodissociated in the absence of (L. The reduction rate
of NCL then is represented by the following equation:
d(N02)
- -ar- - ki > is the primary quantum yield and I is light absorptivity.
The intensity of light measured by this method is represented by the value of
Kd. It corresponds to the primary rate of NCL photodissociation reaction and
_•] £-
has the unit of min .
This method of measuring the intensity of light has some feasiblity depending
upon the requirements for the measurement, and is effective experiment!aly since
it comprises the equipment parameters such as shape,' light spectrum, effective
light path length, etc.
(2) Experimental method
After vacuum cleaning of the Tedlar bag the bag was filled with high purity
N2 gas and then evacuated again. Again it was filled with high purity N2 gas.
After the amount of remaining oxygen was confirmed to be less than 0.1% by the
oxygen meter manufactured by Koritsu Kiki, the predetermined amount of the
167
-------
reference gas of N02 (960 ppm/N2 balance) was introduced and irradiated for 1
minute in •
recorders.
minute in the chamber. The changes of NO and NO were measured by chemiluminescent
A
In this situation, the experiment was carried out with initial NO, concentra-
tion of 4.25 and 0.805 ppm, 1 minute of irradiation time and 9.5 mW/cm of light
source intensity. As a result, a k_. valu
1 _i
with the aimed value of 0.3 to 0.4 min .
source intensity. As a result, a k_. value of 0.3 min was obtained, compared
Also the K, value for natural light was measured by the same method as that
-1
of the chamber experiment using tedlar bag. As the result, 0.27 to 0.67 min
of k, were shown on fine day in summer.
Therefore when K, in the chamber was about 1/2 to 1 of that of natural
light in summer.
2.3.2 JO, obtained from photochemical reaction of propylene-NO-air system.
(1) Outline
Glasson et al reproted the linear correlation between NO photoxidation rate
and N02 photodissociation speed in the photochemical reaction experiment of
propylene-NO system, where NO photo-oxidation rate (R) is repreented by
(NO)Q
2T^" (2.3.1)
where
(N0)o: initial concentration of NO(ppm)
tl/2 : half-life of NO (min)
168
-------
TABLE 2.3.1 (1) KI by static method in chamber
Irradiation Residual Initial cone. Cone, after irradl-
Time 0« cone. (ppm) ation (ppm)
min. % N0x NO . NOx NO
1 0.1 4.35 0.10 4.50 1.15
1 0.1 0.835 0.03 0.83 0.18
TABLE 2.3.1 (2) % by static method in
K. j (min'1) Temp. U.V.
Measured Corrected . mW/cm2
value value
0.276 0.362 33° 9.0
0.206 0.270 30° 9.0
urban
3) Results of Experiment and Considerat
•
Irradiation
Time
Summer
12:30 ^ 1 min
Summer
13:10 'v 1 min
Summer
14:40 **• 1 min
Weather
Fine
Fine
Fine
Initial cone.
(ppm)
NO
X
1.140
0.730
0.260
NO
0.400
0.218
0.003
Cone, after irrad-
iation (ppm)
NO
X
1.180
0.730
0.260
NO
0.670
0.428
0.051
. Kx (min"1)
Measured Value
0.432
0.512
0.206
Corrected Value*
0.567
0.672
0.270
* Correction Coefficient 0.762
-------
Table 2.3.2 Experiment of propylene-NO-air system
a) Conditions set in the chamber
UNIT MEAS. VALUE
Temp. °C 30+2
Humid. % 30
U.V. int. mW/cm2 (300-600nm) 9.5
D.A.F L/hr 134
b) Measured pollutants *
so2
.THC
NfiHC
CO
NO
. X
NO
NO -NO
°3
Unite
pphm
ppmC
ppmC
ppm
ppm
ppta
ppm
ppm
Initial
1.0
1.85
1.75
1
.0.500
0.460
0.040
0.000
12345
-
1.71 1.59 1.45 1.03 0.96
1.60 1.48 1.33 0.90 0.83
0.476 0.426 0.380 ' 0.340 0.294
0.224 0.046 0.000 0.000 0.000
0.252 0.380 0.380 0.340 0.294
0.005 0.028 0.178 0.329 0.431
* Value corrected for dilution
170
-------
TABLE 2.3.2 Propylene + NO + Air Wet Test
a) Test Conditions in the Chamber
^^-^
Temp.
Humid.
U.V.int.
D.A.F.
UNITE
°C
%
MW/cm (300'v600nm)
L/hr
MEAS. VALUE
30+2
55 ^ 70
9.5
218
b) Polutants Measured
Polutants*
S02
THC
NMHC
CO
N0x
NO
NO -NO
°3
Unite
pphm
ppmC
ppmC
ppm
ppm
ppm
ppm
ppm
Irradiation time (hr)
Initial
< 1.0
1.45
1.35
< 1
0.570
0.536
0.034
0.000
1
1.20
1.09
0.536
0.126
0.410
0.011
2
0.98
0.86
0.468
0.000
0.468
• 0.222
3
0.75
0.61
0.368
0.000
0.368
0.389
4
0.71
0.56
0.324
0.000
0.324
0.417
5
171
-------
HQ5
•• 'CL
:. CL
: o'
"; o
- o
rd
-'d
d
2:
0
i:l' "Temp.- 30±2t:
:. Humidity <30%
Initial ' •.
SOadOppb
C0<1 ppm
3:
10
3
G
0 60 120 180 jimg^M|N) 300
;;• Concentration changes on -irradiation 'of .mix-
"- V .- • . vture of-Propylene-v NO* Air
172
-------
f
Q.
sS"
c .
o
o
o*
•»
o
o
z:
o
z:
U.V. intensity
Temp. 30i2°C
Humidity 55-70c/c
'"1 FPm . .
re
o
3
o
120
0
•' 180 240,. N 300
Time (WIN.)
Concentration .changes on irradiation of mix-
"'ture of -Propvlene* NO + Air.
173
-------
(3) Results of Experiment and Consideration
The. photochemical reaction result under the conditions of this experiment wefe compared with
those of the Machinery Technical Laboratory at the tests by Gla*sson et al with a result as shown in the
following Table
TABLE 2.3.4 Results of Photochemical Reaction Experiment of
Mixture of Propylene + NO + Air
Experiments
r
Present experiment
Experiment by Ma- .
chinery Technical
Laboratory
Experiment by W.A.
Glasson et al
Initial Condition
Propylene
(ppmC)
1.75
1.35
4.0
2.0
1
2 ( " )
NO
(ppm)
0.460
0.536
0.5
0.5
0.5
0.5
Humidity
R.H (%)
^oe>^
'55 * 70%
None
n
it
n
*KnBWNvvvff3 £^clpjLu *^X I ui
concentration
rise (min) &&c**si.'5>
£yj#/w>O
sfetr. 52
JI&3F; 40
J&€. 30
a^&-. 45
•sb^. 71
a&&. 40
"^~ kd Value
(min)
J^e—
0,j&
0rHO *
0.35 ^ 0.40 **
^0.29
* Refer to 4-2-1.
** Estimated value at the Machinery Technical Laboratory
-------
TABLE 2.3.5 Comparison of NO Photo-oxidation Speed
in
•
Experiments
Experiment by
W.A. Glasson
et al
Present
experiment
Initial Condition
Propylene
(ppm)
1
2
0.69*
0.87*
NO
(ppm)
0.5
0.5
0.460
0.536
Humidity
R.H (%)
Jsi^i n*j>~
^lonT^
-none
"Woite
None
55 -v* 70
NO photo-
oxidation
speed (rough
value) -_.
- (ppm -rain )
3.5 x 10~3 •
6.3 x 10~3
4.4 x 10~3
6.7 x 10~3
Rough value of
NO photo-disso-
ciation speed
per 1 ppm pro-,
pylene(ppm-min )
3.5 x 10~3
3.2 x 10"3
6.3 x 10~3
7.7 x 10~3
kd Value
(min"1)
0.29
(\ i n__—
(Jm lAr —
<&*£<;>
* Propylene Value obtained by SP. HC meter..
-------
TABLE 2.3.4 Comparison of NO Photo-oxidation Speed
NO photo-oxidation speed
(rough value), -
(ppm-min )
Rough value of NO photo-dissociation
speed per 1 ppm propylene
(ppm-min"!)
3.5 x 10
-3
3.5 x 10
-3
6.3 x 10
-3
3.2 x 10
-3
4.4 x 10
-3
6.3 x 10
-3
6.7 x 10
-3
7.7 x 10
-3
2.7 x 10
,-2
1.8 x 10
-2
-------
This measuring method of the intensity of light is affected by the initial
concentration of NO so that attention should be paid especially to the initial
concentration.
(2) Operation and reaction process of photochemical reaction- experiment was to
be carried out by setting the initial concentration of proylene and NO to 1 ppm
C3 and 0.5 ppm respectively. However, due to excessive dilution, the experiment
was performed with initial concentrations shown in Table 2.3.2 and Fig. 2.3.1.
Further under the same initial conditions, experiment was carried out with
added moisture (55 to 70%R.H.) (see Table 2.3.3).
The experimental result of Glasson et al can not be generally compared with
the above result since the initial concentrations of propylene differ. However
the relative comparison between both results in NO photoxidation rate per 1 ppm
of corrected propylene concentration shows that the rate of the present experiment
can be assumed to be about two times faster than that of Glasson et al.
Also Glasson et al showed the linear relationship between the NO photoxidation
rate and N02 photodissociation rate so that K, value in this experiment can be
also presumed to be higher than that of Glasson1s.
2.3 Photochemical reaction experiment of hydrocarbon-NO-air system
2.4.1 Background reactivity
The high purity and high pressure air in cylinder used for this experiment
contains various gases such as C09, CO, methane, non-methane HC, and NO . Even
c* x
with low concentration of the gases, their effects on the photochemical reaction
may not be negligible. For this reason, we carried out the experiment by carefully
removing HC component from the purified air through molecular sieve 5A and
active carbon trap under ice refrigerant.
177
-------
NO of thermal Oxidation
U.V. intensity
Jemp 30±2'C
Humidity <30*
NOx-NO
I
a
§
I
x
o
Initial
NMHC < 0.1 5 ppmc
S02 < 10 ppb
CO < 1 ppm
O1-
60
120
180
240
300
Time (MIN)
Fig 2.4.1 Concentration changes on irradiation of mixture
of NO + NOx-NO + Air
178
-------
'0.1
U.V. intensity 9.5mw/£rf
Temp. 30±2*C
Humidity 5 5 ~ 7 0
NO
E
£
S
3
x
g
g"
Initial
SO2 < 1 0 ppb
CO < 1 ppm
O3 < 0 ppm
Final
03 0 ppm
NOx-NO
Ol_
60
120
180
240
Time CMIN)
Fig 2.4.2 Concentration changes on irradiation of mixture
of NO+NOx-NO+Air
179
-------
The concentration of each component then was as follows:
Total HC; less than 0.20 ppmC, methane; less than 0.1 ppm, CO; less than 1
ppm, S0?; less than 10 ppb, NO ; less than 5.5 ppb.
Cm J\
When the irradiation experiment was carried out for such background air the
concentration of 03 increased to 0.038 ppm after 4 hours of irradiation. It is
to be noted that this is the reactivity of background air in the smog chamber.
2.4.2 Reaction experiment of NO-air system
Further, we carried out an irradiation experiment in which NO and N02 was
introduced into this background air.
The result of the experiment is shown in Figs. 2.4.1 and 2.4.2.
When the conversion NO to NOp proceedsthrough thermal reaction, it can be obtained
from the folowing oxidation equation:
2NO + 02 K> ^ 2N02
A[NO] = K'[NO]2 [02] * At
where K1 = (1.955 - 0.0232t) x 10"9 (ppm2 min) (t; temperature °C). When the
data shown in Fig. 2.4.1 is substituted into this equaiton, 0.08 ppb/min of NO
thermal oxidation rate is obtained. It is found to be about one half of the
0.19 ppb/min NO oxidation rate during irradiaiton.
Similarly, we' carried out an irradiation experiment with added moisture (55
to 70% R.H.) shown in Fig. 2.4.2, wherein 0.26 ppb/min of thermal oxidation rate
was obtained that was about 1/3 of 0.88 ppb/min of NO photo-oxidation rate. In
view of the above results, in the irradiation experiment with very low HC, the
180
-------
TABLE 2.4.1 Photochemical Roactlvitios of Materials
00
H
Exp.
No.
1
2
3
4
5
6
7
Material
Propylene
Propylene
Propylene
Propylene
Propylene
Toluene
Toluene
NO
D. R.
ppb/min
6.4
4.1
1.6
1.9
6.3
1.4
1.4
Max
ppra
0.92
0.39
0.56
0.39
0.50
0.45
0.30
NOX-NO
t-Max
min
146 '
140
' '300
240
85
300
240
F.R.
ppb/min
6.6
4.2
3.9
3.2
6.B
1.8
1.3
Max
ppm
0.90
0.43
0.06
0.12
0.42
0
0.10
°3
t-Max
mln
300
300
300
300
240
-
270
F.R.
ppb/min
2.2
14
0.11
0.24
1.8
-
0.21
Hydrocarbon (D
THC (it)
3h 5h
26.3 58.5
23.3 51.2
13.9 33.3
18.2 36.4
54.5 59.1*
13.0 19.0
12.5 25.0
.R.)
sp, HC
3h
-
57.7
39.7
43.6
-
13.6
17.3
(X)
5h
-
93.7.
65.7
66.7
-
22.5
59.2
HCHO
ppm
5h
-
0.34
-
0.21
0.48*
0.03
-
T-CHO
ppm
5h
11.3
0.53
0.06
0.69
0.68*
0.04
0.08
NO
5h Dec.
ppm
0.47
0.21
0.06
0.14
0.25*
0.19
0.16
NO
X
1.055
0.500
0.665
0.520
0.570
1.000
0.400
NO
1.035
0.460
0.505
0.500
0.536
1.000
0.400
NO
Non-methan
ppmC
4.00
1.75
1.45
1.35
1.35
5.03
4.80
Exp.
No.
1
2
3
4
5
6
7
Material
Propylene
Propylene
Propylene
Propylene
Propylene
Toluene
Toluene
NO
X
Non-methan
ppmC
3.8
3.5
2.2
2.6
2.4
5.0
12.0
Fumidif led or not
X
X
X
X
55-v.70%R.H
X
X
Pro.
Test
2
1
1
1
1
1
NOX
target
ppm
1
0.5
0.5
0.5
1 • '
0.5
D.R.: Depletion Rate, F.R.: Formation Rate,
sp.HC: measured with CC, 0, data are in 5th,
*: 4h value, - : not measured
-------
rate of NO thermal oxidation should be taken into consideration. Finally it
should be noted that the results of these experiments are not corrected for the
reactivity of the background air.
2.4.3 Photochemical reaction experiment of propylene or toluene-NO-air system
The summary of the irradiation experimental results of propylene or toluene-
NO air system is shown on Table 2.4.1. The rate of decrease (D.R.) of NO was
measured by chemiluminescence method. The rate of formation (F.R.) of 03 was
calculated from the following equation:
03F.R. = (03 max - 03 initial )/2 x t-j/2
^
where 03 max is maximum of 03 in the course of irradiation, 03 initial is the
initial concentration of 03, and t, ,~ is the time (minute) taken for 03 to reach
a half of its maximum concentration. Also the rate of decrease of NO and the
rate of formation of (NO - NO) were calculated according to this equation.
X
The decrease of NO concentration is shown by its change during 5 hour
X
irradiation. This value, measured by a chemiluminescence NO recorder differs
from that of (NO + N02) and is considered to contain all components that can be
reduced to NO by a catalyzer of the NO recorder. The decrease of NO indicates
X X
the loss caused by the oxidation of most of initial NO to N09 and includes the
X w
conversion of NO to components that cannot be reduced by the catalyzer into NO.
When the maximum values of NO -NO, Oo, etc. were not obtained during irradiation,
X w
the irradiation time (up to 300 minutes) is shown as the time for reaching the
maximum concentration.
3. Investigation Method
182
-------
3.1 Outline of Investigation
The chamber carried on the photochemical smog chamber vehicle, as mentioned
in the previous section 1.3, has the inner volume of 2 m3 which is usually
smaller than that of other fixed chambers. THus, the continous running of measuring
all instruments is difficult during irradiation. Hence, as shown below, the
investigation was carried out by opeating some instruments intermittently or
omitting the measurement of some pollutants that seemed not directly related to
such reaction.
3.1.3 Method of this investigation
The experimental procedures of this investigation are as follows;
1) The inside of the chamber is vacuum cleaned the day before the investigation.
2) The temperature in the chamber is in principle set to 4°C higher than
ambient temperature in order to prevent the formation of dew within the chamber
during sampling.
3) After setting the pressure in the chamber to atmospheric pressure by manual
air sampling valve, ambient air is sampled by air sampling blower.
4) Air is sampled until the inside of the chamber is filled with the ambient
sample air.
5) By using analytical instruments, carried on the analyzing vehicle, the
concentration of each component within the chamber is quickly measured (hereinafter
referred to "initial concentration").
6) After the measurement of the initial concentration, ultra-violet irradiation
is started. The temperature in the chamber is then maintained constant to
maintain the intensity of UV radiation.
183
-------
Table 3.1.2 Analytical method
00
Measurement Items Chemical formula or
abreviation
Analytical method
Pollutants
1 Total aldehyde (aliphatic) - -
2 Formaldehyde HCHO
absorbed light intensity method 'accord-
ing to M.B.T.H method
pararosanilen method
Ambient air measurement
1 Wind direction -Wind velocity
2 Temperature-humidity
3 U.V ray intensity
anemoscope • anemometer
Themometer, Hygrometer
Integrated irradiation recorder
4 Visible ray intensity ««
5 U.V ray intensity by wave length
UV spectrophotometer
Irradiation condition
1 Temperature in chamber
2 "Humidity in chamber
,3 UV ray intensity
Dew cell method
ii
UV spectrodetector
* CO meter on Table 1.4.1 was not used for certain reasons.
-------
7) After the irradiation, digital air flowmeter is'read at a certain time
interval (about 1 hour) to calculate the dilution rate of sample in the chamber.
The irradiation is continued until the dilution reaches at least 30%.
8) The inside of the chamber is vacuum cleaned after the completion of the
irradiation.
3.2 Pattern of photochemical reaction
3.2.1 Outline
The pattern of the photochemical reaction generally becomes as follows.
When the irradiation of light is started, initial oxidation of NO to N02 is
promoted rapidly to decrease hydrocarbon and increase aldehydes.
The accumulation of 03 is started from the period when NO concentration is
considerably decreased. The increase of 03 becomes remarkable when N02 concentra-
tion passes over the maximum value and then decreases. The decrease of hydrocarbon
and increase of aldehydes tend to continue until the concentration of 0, increases
to its maximum concentration and begins to decrease.
Such general trend is noted not only in the irradiation experiment of
artificial mixture but also in that of actual ambient air sample. However
distinct trend was not sometimes discerned since the initial concentrations of
consittents varied and some gas analysis was still unsatisfactory.
The reaction pattern of the irradiation experiment will be analyzed princi-
pally with respect to the trend of 03 formation.
The 0- formation is much affected by the initial concentrtaions of hydrocarbon
O
and NO When the concentrations of both substances are high the maximum concentra-
tion of 03 reaches to high value. It is clarified that in particular the initial
concentration of hydrocarbons apparently has close relation to the maximum
concentration of 0-
185
-------
3.2.2 Method of Measurement
In the irradiation experiment the entire sample is charged in the chamber
at the beginning. Since there is no subsequent sample injection the irradiation
time is also the reaction time. The irradiation was continued by artificial
light sourch shown in section 1.4 for 3 to 6 hours. During this irradiation,-
continuous or intermittent measurement of concentration of components in the
chamber, i.e., NO , NO, 09, total hydrocarbon and methane, nonmethane hydrocarbon,
At -
CO, etc. (see Item 3.1.1) was carried out.
In order to avoid the pressure reduction caused by the consumption of
sample for analysis in the reaction chamber, purified air contained in cylinder
was automatically introduced to keep the pressure balance.
The intensity of irradiation was set to the maximum limit of intensity
measured in order of about 13 mW/CM2 within the range of the allowance of light
source capacity.
The absolute value of the irradiation intensity, however, encounters
problems such as correction of incident angle of light onto detector and others
so that it may not be compared with other measured intensity.
The temperature in the reaction chamber was controlled, but due to the
effect of the ambient temperature it was slightly higher than the preselected
level.
The measurements of NO, NO and hdyrocarbon concentrations were carried.out
X
continuously and other constitutents by'intermittent measurement. In the early
investigation, some analzers had malfunctions. Also in the measurement of NO
and NO by chemilimunescence method, the concentration of N02 tends to be
uncertain. There was an experiment in which the measurement of N02 and NOX was
carried out by Saltzman method, though it was not simultaneoulsy conducted with
the chemluminescent method.
186
-------
The measurement of aldehyde and other constituents was also carried out.
However it will be described in another paragraph.
4. Results of Investigation
4.1 Arrangement of experimental data
In the photochemical reaction investigation by the mobile smog chamber,
about 110 experiments were carried out in the areas around the Tokyo Bay and
Osaka Bay from 1972 to 1975.
In 102 cases of these experiments, ambient air was sampled in the morning.
Measured and analyzed results somewhat differed with regard to the investigated
areas and years. Results included those from automatic measurements of NO (NO,
J\
N02), HC (THC, CH4), S02> CO, 03> OX, and temperature, humidity and intensity of
ultra-violet irradiation in. the chamber, as well as those from manual measurements
of hydrocarbon composition, PAN, aldehydes, aerosol, etc. In addition, the
dilution of air within the chamber, the meteorological conditions during air
sampling, etc. were measured.
The present statistical- analysis attempted to explore relationships between
the increase of 0.,, and the composition of non-methane hydrocarbon, initial
concentration of NO , and ultra-violet light irradiations.
J\
The experimental data used for this analysis are shown in table 1 and the
classification of hydrocarbon composition in Table 2.
28 cases among 102 examples were excluded since the dilution rate and the
concentrations of CH* and 0- were uncertain, and the remaining 74 examples were
analyzed.
187
-------
The items in the tables are as follows:
1) List of Experimental results shown in Table 1
(i) Initial Value
Value of non-methane hydrocarbon, NO , HC/NOv (ppmC/pphm) ratio, and
A A
03 concentration before ultra-violet irradiation.
(2) Uncorrected value
The increase (A03) of 03, i.e., the maximum concentration of 03 (03
max) after ultra violet irradiation minus the initial concentration of
03, provided it is not corrected for dilution.
(3) Time for 03 maximum to be attained
Time from the beginning of ultra-violet irradiation to the appearance
of the maximum 0., concentration. It was described as 5 hours when 03
was still in the incerasing at the completion of experiment in 5
hours.
Further the time was encircled with mark 0 when the experiment was
completed within 5 hours.
(4) Corrected value
The maximum concentration of CL (CL max) corrected for the dilution
effect of sample air, and corrected increase of 03 concentration ( (L)
that is (L concentration max minus the initial concentrations.
All~of these value were used for the analysis.
188
-------
The following equation was used for the correction;
C - Co eVt/V°
Where C : Corrected concentration after t hours
, s
Co : concentration measured after t hours
Vo : volume of chamber
V : volume of air supplemented in unit time
t : time
(5) Ultra-violet light
Intensity of ultra-violet irradiation, irradiation time until the
maximum concentration of CL appears and Dose (intensity of irradiation
X irradiation time)
>
2) Content of table 2 of hydrocarbon composition
(1) The composition was classified for 72 cases, in which the composition
of hydrocarbon was analyzed out of 74 experiments shown in table 1.
(2) The composition was classified, according to the group classification
of hydrocarbon in table 3, into 3 dividions, i.e., parrafins, oleffins
and aromatics. The ppb concentration was converted to ppbC by being
*
multiplied by carbon number.
(3) The initial concentration is the concentration before the ultraviolet
irradiation and the final concentration is the concentration after the
ultra-violet irradiation. Also the ratio of the final concentration
to the initial concentration (rate of decrease) was represented by %.
(4) The initial composition was the percentage of the initial concentration of
Paraffins, olefins and aromatics.
189
-------
TABLE 4.1.1 Results of Experiment
NO. Non-methan
Ex.
1.
2.
3-
4.
5.
6.
-7.
3.
9.
"10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
21.
22.
23.
24.
25.
26.
27.
28.
29.
. 30.
31.
32.
33.
34.
35.
36.
37.
38.
39'.
40.
41.
42.
43.
44.
45.
46.
47.
48.
49.
50.
"51.
52.
53.
.54.
- 55.
56.
" 57. •
58.
59.
60.
61.
' 62.
63.
64.
65.
66.
67.
"68.
69.
76.
71.
"72.
73.
74.
ppmC
1.3
"1.4
1.3
4.1
1.1
0.9
7.4
1.5
5.7
1.1
0.5
1.9
2.3
1.7
1.7
1.6
0.4
1.5
1.5
0.9
1.6
2.5
1.5
1.0
1.0
0.9
0.4
2.0
0.8
1.1
0.5
0.3
0.6
1.3
0.6
1.3
1.5
0.7
1.7
1.2
0.9
0.8
1.0
0.8
1.0
1.0
2.1
1.0
1.2
0.8
0.2
0.6
0.2
0.9
0.3
0.8
0.6
0.3
- 0.3
0.6
1.8
2.5
0.5
0.8
1.4
0.7
0.6
0.2
0.2
0.3
0.4 '
0.1
0.1
0.1
Initial
value
Value not corrected H2 untij. 03 Corrected value
NO Non-methan/NO 0, (0, max.) (AO-) max' value n max
x x j 3 3 obtained 3
pphm ppmC/pphm
5.3
4.2
4.0
7.0
4.7
4.0
- 8.0
12.4
7.9
9.4
7.1
12.5
26.5
16.2
25.5
31.0 -
10.5
8.0
13.5
4.5
19.0
10.5
19.0
3.6
6.0
4.0
5.0
3.0
4.5
5.5
2.2
4.1
5.5
6.3
3.5
5.0
3.5
2.5
3.5
3.5
1.6
3.0
1.6
1.0
1.5
2.5
4.1
0.5
8.5
3'.0
2.0
1.0
1.5
4.0
1.1
6.6
4.0
2.0
3.5
5.5
4.6
5.7
3.4
4.0
8.0
4.6
1.1
1.8 '
1.2
1.9
. 2.1
0.9
1.2
0.9
0.25
0.33
0.33
0.59
0.23
0.23
0.93
0.12
0.72
0.12
0.07
0.15
0.09
0.10
0.07
0.05
0.04
0.19
0.11
0.20_
. .0.08
. 0.24
.. 0.08
0.28
0.17
0.23
0.08
0.67
0.18
0.20
0.23
0.20
0.11
0.21
0.17
0.26
0.43
0.29
0.49
0.34
0.56
0.27
0.63
0.80
0.67
0.40
0.51
7.00
0.14
0.27
0.10
0.60
0.13
0.23
0.27
0.12
0.15
0.15
0.09
0.11
0.39
0.44
0.15
0.20
0.18
0.15
0.55
0.11
0.17
0.16
0.19
0.11
0.08
0.11
pphm
2.2
0.8
1.5
0.0
1.7.
4.7
0.0
1.2
1.5
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
4.0
1.2
1.0
0.5
8.0
0.0
3.0
3.0
0.5
0.5
0.5
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
1.2
0.0
2.0
3.0
1.0
1.3
0.0
4.0
0.0
0.8
1.0
(0.0)
1.5
0.0
1.0
0.0
0.0
0.4
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.3
0.0
0.0
0.0
0.0
0.2
0.3
pphm
8.8
8.5
7.5
14.7
10.6
9.5
17.5
16.7
20.0
12.0
8.7
13.7
18.5
13.7
15.0
19.5
.8.5
8.2
9.0
4.3
•13.4
14.6
14.9
8.2
6.8
4.5
3.6
• 4.5
7.5-
11.0
7.5
10.5
9.5
11.3
3.0
2.5
3.5
5.5
5.5
6.5
3.0
5.0
3.5
4.0
3.5
3.1
6.9
4.5
5.0
4.6
2.5
2.5
3.0
4.6
2.4
4.5
3.3
4.5
4.0
6.5
2.1
2.0
0.7
1.4
4.1
3.7
0.6
3.4
1.7
2.2
2.5
2.0
2.0
2.2
pphm
6.6
7.7
6.0
14.7
8.9
4.8
17.5
15.5
18.5
12.0
8.7
13.7
18.5
13.7
15.0
19.5
3.5
4.2
7.8
3.3
12.9
6.6
14.9
5.2
3.8
4.0
3.1
4.0
7.5
11.0
7.5
10.5
9.5
11.3
3.0
2.5
3.5
5.5
5.5
6.5
1.8
5.0
1.5
1.0
2.5
1.8
6.9
0.5
5.0
3.8
1.5
2.5
1.5
4.6
1.4
4.5
3.3
4.1
4.0
6.5
2.1
2.0
0.7
1.4
4.1
3.7
0.6
3.1
1.7
2.2
2.5
2.0
1.8
1.9
hr
5
5
5
2
4
5
2
3
3
5
5
5
5
3
5
5
5
2
3
5
4
3
(4)
5
(3)
5
5
(4)
4
5
5
5
5
5
(4)
(4)
5
4
5
(4)
(3)
5
3
5
(4)
(4)
5
5
5
5
(4)
(4)
5
5
4
5
5
5
4
5
4
1
1
3
3
3
(4)
3
5
5
5
5
5
5
pphm
11.4
12.8
10.1
16.8
12.7
12.2
18.6
19.0
22.6
15.7
10.4
18.1
25.5
16.4
20.0
26.1
11.6
3.3
10.2
4.9
15.7
16.2
15.4
9.9
7.3
5.6
4.5
5.4
8.8
14.2
10.7
14.1
12. 8
14.2
4.2
3.4
5.1
7.2
7.2
8.3
3.7
5.8
4.4
4.8
4.4
3.8
- 8.6
5.8
6.2
6.1
3.8
3.5
4.0
6.2
2.9
5.5
4.2
5.3
4.6
7.5
2.9
2.2
0.8
• 1.7
4.8
4.6
0.7
4.1
2.3
2.9
3.2
2.4
2.6
2.6
AO,
pphra
9.2
12.0
8.6
16.8
11.0
7.5
18.6
17.8
21.1
15.7
10.4
18.1
25.5
16.4
20.0
26.1
11.6
4.8
9.0
3.9
15.2
8.2
16.4
6.9
4.3 ~
5.1
4.0
4.9
8.8
14.2
10.7
14.1
12.8
14.2
4.2
3.4
5.1
7.2
7.2
8.3
2.5
5.8
2.4
1.8'
3.4 .
2.5
8.6
1.81
6.2
5.3
2.8
3.5
2.5
6.2
1.9-
5.5
4.2
4.9
4.6
7.5
2.9
2.2
0.8
1.7
4.3
4.6
0.7
3.8
2.3
2.9
3.2
2.4
2.4
2.3
Ultraviolet ray
Strength
max/cm
13.4
13.1
13.1
12.1
12.1
12.1
12.9
12.6
12.3
12.1
12.1
7.3
7.3
7.3
7.5
7.3
7.3
12.5
12.5
12.0
12.0
12.5
12.5
12.5
11.1
12.5
12.5
13.0
6.6
7.1
7.0
7.0
6.9
7.0
12.5
12.5
12.6
13.5
13.5
13.5
13.5
13.5
13.5
13.5
13.5
6.0
.r5.0
5.9
5.1
5.0
5.0
4.9-
5.0
4.9
7.2
7.8
7.5
7.2
7.5
7.8
6.7
6.2
6,2
6.7
9.0
9.0
9.1
9.1
8.2
8.2
8.5
8.2
7.9
7.9
Srs. Sosi
hr MW/cm2-hr
5
5
5
2
4
5
""1. '
3
3
5
5
5
5
3
5
5
5
2
3
5
4
3
4
5
3
5
5
4
4
5
5
5
5
5
4
4
5
4
5
4
3
5
3
5
4
4
5
5
5
5
4
4
5
5
4
5
5
5
4
5
4
1
1
3
3
3
4
3
5
5
5
5
5
3
67
66
66
24
43
61
26
38
37 '
61
61
37
37
22
38
37
37
25
38
60
43
38
50
63
33
63
63
52
26
36
35
35
35
50
50
63
54
68
54
41
68
41
63
54
24
30
30
26
25
20
20
25
25
29
39
38
36
30
39
27
6
6
20
27
27
36
27
41
41
43
41
40
40
"J 1
-------
Initial Value
Ho.
Ex.
12.
14.
15.
16.
35.
36.
37.
33.
39.
40.
41.
42.
43.
45.
46.
47.
48.
61.
62.
63.
64.
65.
66.
67.
68.
69.
70.
71.
72.
73.
74.
N0x
pphm
12.5
16.2
25.5
31.0
3.5
5.0
3.5
2.5
3.5
3.5
1.6
3.0
1.6
1.5
2.5
4.1
0.5
4.6
5.7
3.4
4.0
8.0
4.6
1.1
1.8
1.2
1.8
2.1
0.9
1.2
0.9
Non-methan
ppmC
1.9
1.7
1.7
1.6
0.6
1.3
1.5
0.7
1.7 •
1.2
0.9
0.8
1.0
1.0
1.0
2.1
1.0
1.8
2.5
0.5
0.8
1.4
0.7
0.6
0.2
0.2
0.3
0.4
0.1
• 0.1
0.1
A + 0
pptnC
0.469
0.532
0.917
0.816
0.382
0.465
0.562
0.399
0.648
0.352
0.385.
.0.224
0.440.
0.322
0.791
0.606
0.673
0.606
0.429
0.080
0.197
0.295
0.277
0.073
0.080
0.075
0.132
0.173
0.039
0.043
0.029
Benzene
ppmC
0.059
0.010
0.012
0.009
-
0.090
0.072
0.038
0.014
0.034
-
0.180
0.120
-
-
-
0.037
0.042
0.007
0.013
0.022
0.017
0.005
0.006
0.008
0.015
0.021
0.005
0.005
0.003
A + 0 -
Benzene
pp&C
0.410
0.522
0.905
0.807
0.382
0.375
0.490
0.361
0.634
0.268
0.385
0.224
0.260
0.202
0.791 '
0.606
0.673
0.569
0.387
0.073
0.184
0.273
0.260
0.063
0.074
0.067
0.127
0.152
0.034
0.038
0.026
Value not corrected Corrected value
°3
pphm
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
1.2
0.0
2.0
1.0
1.3
0.0
4.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.3
0.0
0.0
0.0
0.0
0.2
0.3
Oj.max
pphm
13.7
13.7
15.0
19.5
3.0
2.5
3.5
5.5
5.5
6.5
3.0
5.0
3.5
3.5
3.1
6.9
4.5
2.1
' 2.0
0.7
1.4
4.1
3.7
0.6
3.4
1.7
2.2
2.5
2.0
2.0
2.2
403
pphm
13.7
13.7
15.0
19.5
3.0
2.5
3.5
5.5
5.5
6.5
1.8
5.0
1.5
2.5
1.8
6.9
0.5
2.1
2.0
0.7
1.4
4.1
3.7
0.6
3.1
1.7
2.2
2.5
2.0
1.8
1.9
H2 until Oj
obtained pphm
5
3
5
5
(4)
(4)
5
4
5
(4)
(3)
5
3
(4)
(4)
5
5
4
1
1
3
3 '
3
(4)
3
5
5
5
5
5
5
0, max
pphm
18.1
16.4
20.0
26.1
4.2
•3.4
5.1
7.2
7.2
8.3
3.7
5.8
4.4
4.4
3.8
8.6
5.8
2.9
2.2
0.8
1.7
4.8
4.6
017
'4.1
2.3
2.9
3.2
2.4
2.6
2.6
AO, Year Season
pphm Syowa
18.1 47 V Kamata
S
16.4
.20.0
26.1
4.2 49 S SumiyoshiSu
3.4
5.1
7.2
7.2
8.3 .
2.5
5.8 Fujiidera
2.4
3.4
2.5 Ohyamazaki
8.6
1.8
2.9 50 S Ohyamazaki
2.2
0.8
1.7
4.8
4.6
"0.7 Chiba
3.8
2.3 Tochigi
2.9
3.2
2.4
2.4
2.3
Notes : No. 12 * 17 : Ethan, ethylen inseparable and excluded from calculation.
No. 35 * 45 : Ethan, ethylene, propane and propylene.
Aromatics was measured up to m.p-xylene.
191
-------
TABLE 4.1.2 Composition of Hydrocarbon
Paraffins
No.
. Ex.
Initial
ppb. c
Final
ppb. c
Final/
Initial
Z
Oleffins
Initial
ppb. c
Final
ppb. c
Final/
Initial
Z
Aromatics
Initial
ppb. c
Final
ppb. c
Final/
Initial
Z
Initial com-
position ratio
P : D
Z
: A
s
.A/? Remarks
1.
2.
3.
4. . •
5.
6.
7.
3.
9.
10.
11.
12.
355
279
79
70
41
59
399
43,
8, 48
1.1 Ini.30m, Fin.4h
13.
14.
15.
16.
17.
18.
19.
20.
21.
22.
23.
24.
25.
26.
27.
28.
29.
30.
31.
32.
33.
34.
35.
36.
37.
33.
39.
40.
41.
42.
43.
44.
45.
46.
47.
48.
49.
50.
51.
52.
53.
54.
55.
56.
57.
58.
59.
60.
61.
62.
63.
64.
65.
66.
67.
68.
69.
70.
71.
72.
73.
74.
439
555
579
135
452
381
267
529
1,940
2,653
228
364
390
248
925
9
24
39
35
16
9
214
362
1S7
260
209
154
147
158
94
222
112
173
301
129
65
45
21
18
9
31
9
64
34
35
81
357
155
52
81
173
138
59
40
81
141
121
39
28
21
468
217
317
121
513
. 174
332
680
294
230
207
164
74
366
17
29
16
401
8
127
294
182
98
123
135
90
117
63
89
173
76
41
55
16
12
16
31
66
8
7
74
255
75
32
42
96
103
66
51
53
85
160
32
35
29
107
39
. 55
90
135
65
63- .
35 '
11 '
101
57
42
30
4C»
189
74
46
2,506
89
59
81
97
38
80
85
96
53
56
51
57
59
63
122
76
67
178
100
103
24
20
91
71
48
62
52
55
75
112
128
65
60
132
82
125
138
67
85
76
24
*
5
25
29
•40 .
8
8
3
10
4
4
5
16
48
34
63
29
17
17
35
11
10
25
13
14
17
4
7
5
26
24
28
16
.
6
4
4
4
4
34
16
13
42
23
17
11
15
16
4
12
4
4
10
3
2
1
39
28
37
67
<
75
40
100
100
80
213
33
38
67
79
100
65
43
145
40
48
31
29
59
75
29
20
. 465
. 832
. 740
. 507
. 381
. 862
. 162
174
.1,361
179
151
. 386
. 519
. 479
. 639
68
. 276
. 103
. 204
. 507
. 109
. 377
. 440
. 533
. 359
. 640
. 344
. 382
214
. 436
.1,070
. 317
. 775
. 558
. 639
. 408
. 247
89
79
73
. 128
11
. 116
61
59-
88
. 106
. 543
. 400
63
. 180
., 260
. 266
63
55
62
. 118
. 156
35
36
24
409
575
664
1,121
167
84
121
399
420
129
144
126
196
235
79
108
407
629
72
147
51
310
241
180
366
324
278
271
551
. 499
443
124
128
108
1C8
84
140
21
64
72
49
52
70
370
219
64
135
128
149
50
65
38
50
• 72
19
83
69
90
221
19
52
70
29
235
85
37
24
41
37
116
105
200
124
66
39
12
58
67
. 52
. 171
74
26
85
71
89
70 •
30
52
121
137
115
109
191
55
118
83
59
66
68
55
102
75
49
56
79
118
61
42
46
77
75
79
45,
38,
42,
20,
36,
44,
25,
42,
48,
30,
28 ,_
41,
18,
17,
26,.
• 18,-
33,
10.
*>,
*'r
4U,
2»,
JV,
",
45,
• 33,
52,
52,
41,
50,
40.
4i,
7, 48
6, 57
5, 53
4, 76
1, 63
3, 53
4, 71
1, 58
2, 50
2, 68
1, 72
3, 56
1, 82
Oj 83
1, 73
2, 80
5, 68
4, 80
/, 50
5, 68
13, 43
•6,- 65
7, 56
3, 64
7, 48
21, 46
9, 40
i, 4J
b, DJ
5, 45
10, 51
10, 49
1.1
1.5
1.3
3.8 Ini.30ra
0.8
2.3
0.6
0.3
Ini.30m,Fin.4h
Fin.^fe
0.7 Fin.4.5h
7.6
2.6
5.8
31.7
12.1
1.2
3.1
2.2
2.6
4.6
4.8 Ini. Ih
2.8
6.3 Fin.4h
5.5
4.2 Fin.4h
4.4
8.1
4.1
1.2
1.8
1.8
2.5
1.3 Fin.4h
1.5 Fin.4h
Fin.4h
1.2 Fin.4h
1.5
1.9
1.1 Fin.4.5h
1.4
0.8 -
0.8
1.3
0.9
1.3
1.1
Notes: The final concentration values are not corrected
No. 12 * 17, So. 35 •v 48 : Ethan, Ethylene inseparable and excluded from calculation.
No. 18 % 48 : Ethan, Ethylene, propane and propylene.
192
-------
Table 4.1.3 Table of hydrocarbon classified by group
Paraffins
saturated hydrocarbon
Oleffins Aromatics
unsaturated hydrocarbon aromatic hydrocarbon
ethane
propane
;iso-iutan
n-lut'an
' * •
iso-pentane
n-pentane
2-methyl pentane
3-methyl pentane
n-hexane
2-4 dimethyl cyclopentan
methyl cyclopentane
2-methyl hexane
1*3 dimethylcyclopentane
n-heptane
2-methyl heptane
3 methyl heptane
n-octane
2-2 dimethyl butane
2-2 dimethyl butane
2-3 dimethyl butane
2 ethylene
3 propylene •
4 1-butene
4 iso-butene
5 trans-2-butene
5 cis-2-butene
6 1 • 3 • butadiene
6 2-methyl butene
6
7
7
7
7
7
8
8
8
7
6
6
2 benzene 6
3 toruene ' 7
4 ethyl benzene 8
4 m-p-xylene 8
4 m-p-xylene 8
4 iso-propyl benzene 9
4 m-p« ethyl toruene 9
4
The last number is carbon number.
193
-------
Further aromatics/parraffins (A/P) was shown only for the experiment in
which aromatics was measured up to o-xylene.
(5) In addition, the sume of oleffins and aromatics as active hydrocarbon minus
benzene, (A + 0 - benzene), was calculated. But it was not listed in the
table.
(6) Further, the final concentration of hydrocarbon is the one uncorrected for
the dilution.
4.2 Range of initial concentration
Since the experiments by the mobile smog chamber were carried out in selected
areas having different air polltuion levels and area! conditions, the initial
concentration of NO and HC covering the wide range of concentration from low to
A
relatively high concentration was obtained.
Table 4.2.1 shows the distribution of initial concentration
Non-methane hydrocarbon (hereinafter briefly referred to NMHC) exceeded 2.0
ppmC in 8 examples in which the maximum concentrtion was 7.4 ppmC.
The range of most frequent HC concentration as shown in Table 4.2.1,
3.8 - 1.0 ppmC and the average concentration was 1.2 ppmC.
Also only 7 cases of the measurements had a range (2-4 ppmC) of considerably
high concentration of NMHC.
NO concentration was the sum of NO concentration measured by chemiluminscence
A
method and N02 by Saltzman's method. Its maximum concentration was 31.0 pphm,
the minimum 0.9 pphm and the most frequent one covered the range from 3.1 to 4.0
pphm, the average being 6.0 pphm.
194
-------
TABLE 4.2.1 Distribution of Initial Values
HC NO HC/NO
j£ 2
„, - Num. of _, Num. of _, Num. of
Class Class - Class n
example example example
ppm.c ' pphm f ppmc/pphitf
under
0.0 n, 0.2 3 0.0 -v 1.0 5 0.00 -\- 0.10 12
0.2 *
0.4 «
0.6 "
0.8 «
1.0 "
1.2 «
1.4 *
1.6 *
1.8 '
2.0 '
>. 0.4
>• 0.6
o 0.8
>. 1.0
»• 1.2
»• 1.4
u 1.6
»» 1.8
o 2.0
u
8
6
8
12
9
6
7
5
2
' 8
1.1 *>
2.1 -v
3.1 -v-
4.1 *>
5.1 ^
6.1 ^
7.1 ~
8.1 «v
9.1 -v
10.0 -v
2.0
3.0
4.0
5.0
6.0
7.0
8.0 .
9.0
10.0
15.0
12
7
13
10
6
3
5
1
1
5
0.11 ^
0.21 -x-
0.31 *
0.41 -^
0.51 ~
0.61 -v
0.71 ~
0.81 -v
0.91 ^
0.20
0.30
0.40
0.50
0.60
0.70
0.80
0.90
28
14
5
3
5
3
2
2
Total
• 74
15.1
Total
6
74
• Total
74
195
-------
/O
/
Fig'4.3.1 NOX andA03
196
-------
io
/o
O .
/
Fig 4.3.2 NMHC and A03
197
-------
0.11 - 0.20 of HC/NOV (ppmC/pphm) were the most frequent values. The
A
maximum was 2.00 and the minimum 0.007. 5 examples exceeded HC/NO of 0.63 for
A
which no high 0^ concentration was observed. Since no case was less than 0.025
of the ratio no through consideration could be made in this range.
4.3 Single Correlation Analysis
4.3.1 Study of results by correlation diagram
To grasp first generally the relationships between AO, and NO and between
2.0 ppmC) to show the relationship between,
NO and AO-, i.e. A03 corresponding to the initial concentration of NMHC.
The results are shown in Fig. 4.2.3 (1) - (5).
198
-------
TABLE 4.3.1 Correlation between Initial N0x and A03 in NMHC Class
Initial NKHC
Class
Logarithmic one-dimension
regression formula
Correlation
Number erf data
ppmC
0
0.5
1.0
1.5
2.0
•v. 0.
•v Q.
^ 1.
•v 1.
"*
4
9
4
9
log
log
log
log
log
[A03]
[A02]
[A03]
W>3]
U03]
- 0.645
- 0.757
- 0.638
" 0.793
- 0.776
log
log
log
log
log
[N0x] +
INO l ~t*
[NO 1 *t*
[soxl +
[N0x] +
0.320
0.276
0.416
0.206
0.341
0
0
0
0
0
.912*
.535**
.689**
.851**
.604**
14
23
17
12
8
** Level of significance 1%.
* Level of significance 5Z.
TABLE 4.3.2 Correlation between Initial NMHC and iOj in NO^ Class
Initial NO
Class *
pphm
0 •<• 1.9
2.0 T 4.9
5.0 * 9.9
10.0 -v.
Initial HC/NO
Class *
0 * 10
11 •*• 18
19 * 28
29 •>/
Logarithmic one-dimension
regression formula
log CA03] —0.070 log tHC] + 0.329
log [AOj] - 0.350 log [HC] + 0.750
log [AOj] - 0.296 log [HC] + 0.868
log [A03] - 0.164 log [HC] + 1.167
TABLE 4.3.3 Correlation between Initial
Logarithmic one-dimension
regression formula
log [A03] - 0.771 log [NOxJ + 0.245
log [A03] - 0.684 log [N0x] + 0.299
log [A03] - 0.503 log [N0x] + 0.491
log [A03] - 0.898 log [N0x] +0.276
Correlation Number of data
-0.157 " 15
0.326* 30
0.352 13
0.208 11
HO and 0, in HC/NO Class
Correlation . Number of data
0.979** 11
0.761** 23
0.407 "20
0.275 20
199
-------
logCA08 3=0.645 log CNOX3+032
ACb
(pphn
20
10
S
1
)
.
•
,
4
1
/
'
7
'
V
7
\.f
siz • •
73 >
'S*6*
•55
• (
Sw
53
-
.
.
aa
8 s
*71
51
^
-
•
Xss
"
^
/
S
A
tt
•^
^
.
•jjX
S'
/
;acked figures
e test number-
/
show
1 5 10 20
NOx
(pphm)
Fi'g 4. 3. 3 (1) Correlation'between N03 and A03 (NMHC 0—0.4 ppmC)
200!
-------
logCA03 3 = 0.757 log CNOXD+0.276
ACh
Cpphn
"20
10
5
1
)
•
*
r
=
0
i
/
.535*=*
52
/
44
D J
C
>
X
• 4i
•
•s:
(
/
1
^
-
\
42
sn x
/*5 ;
'
•32
• 2
6
"id'
/
26
7-6
•ii
64
•3
(?f
•/
S
S
V
1 1
s
6
^
'
/
/
~
i
1 5 10 20
NOx
(pphnO
Fig 4.3.3(2) Correlation Between NOX and AQ3 (NMHC 0.5 — 0.9 ppmC)
201
-------
log CA03 3=0.638
ACb
(pphn
20
10
5
1
.
.*
s
4!},
•
s*^
r=
/
s
0.
f
689**
s
"y
-------
logC A 03 3 = 0.793 log C NOx3+0206
AOs
Cpphn
20
10
5
1
}
•
-
•
,
••
-------
logCA03 3 = 0.776 log CNOX3 +0341
AOs
(pphir
20
10
5
1
)
*
'
*,
*
T
=
0.
604**
•
-
*
/
>
/
28
• 47
/
X
/
•
,
/
•
62
•
4
4
/
9
7
/
•
/
/
/
.22
/
s
+
/.
' 13
I 5 10 20
NOx
(pphm)
Fig 4.3.3(5) Correlation between NOX and AQ3 (NMHC 2.0ppmO~)
204
-------
According to this result, the relationship between NO and A(L was approxi-
mately linear on logarithmic paper except when the initial concentration of NMHC
wer 0.5 - 0.9 ppmC.
From this confirmed relationship, single correlation model was assumed
wherein the relationship between NO and 0- was made exponential for each
A O
division of the initial concentration of NMHC., i.e.,
[A03] = a [N0x]b (4.3.3)
Taking common logrighm of both sides, we obtained
log [A03] = log a + b log [NOX] (4.3.4)
to determine factors log a and b by the method of least square.
This result is shown in Table 4.31. If was found that considerably close
correlation existed in all cases.
4.3.3 Relationship between NMHC and A03
Next the initial concentration of NO was divided into 4 classes (NO 0 -
1.9, 2.0 - 4.9, 5.0 - 9.9 and > 10.0 pphm) to show the relationship between NMHC
and A03 corresponding to the initial concentration of NMHC.
The results are shown in Fig. 4.3.4, (1) - (4).
In view of these results, the relationship between NMHC and A0~ is consider-
ably meager. Particularly in the small range of NO concentration points were
A
distributed in the horizontal or ellipse-like shape. In the same way as that in
the case of NO , regression equation was obtained from these points as shown in
A
Table 4.3.2. Significant correlation was not obtained except for when the
initial concentration NO was 2.0 - 4.9 pphm.
X
205
-------
4.3.4 Relationship between NO or NMHC and AO, according to the division of
X j
HC/NO ratio and others.
Furhter, HC/NO ratio was divided into 4 divisions (NMHC/NCV = 0 - 10, 11 -
X X
18, 19 - 28 and >29 ppmC/ppm) to show the relationship between NO or NMHC and
/\
03, i.e., A03 corresponding to the initial concentration of NOX-
The results are shown in Fig. 4.3.5 (1) (4).
In view of the results,-the relationship between NO and AO- in any divisions
X «3
showed approximately rightward-ascending one. In the same way as before, regres-
sion equation was obtained with respect to this relationship. It is shown in
Table 4.3.3. It was found that there was considerably close correlation in all
cases.
In addition, the relationship between UV Dose or UV intensity and
A03 was also contemplated.
Though UV Dose was considered to be an important factor for AO,, there was
found no distinct relationship between them. This, was possibly because the
formation of ozone was affected mainly by the initial concentrations of NO and
X
NMHC so that the time taken for the concentration of ozone to be maximized
varied remarkably. Accordingly when the ultra-violet light was considered as a
factor, it seemed suitable to use the intensity of ultra-violet light. This
will be described later.
4.4 Multiple Correlation Analysis
In the previous section, the single correlation analysis of NOV and 0,,
X o
etc. was carried out. In this section, we attempted to obtain multiple correlation
as the product of NO , HC, UV intensity and concentration of olefins = aromatics
in HC.
206
-------
(pphm)
logCAQ, D=- 0.07 00 logCHCD+0.329
7=-0.157
20
10
45
48
74
69
43
55
bV
0.5
01
05
10
20
NMHC
(pphm)
Fig 4.3.4(1) Correlation between NMHC and A03 (NO x 0-0.9 pphm)
207
-------
3 = 0.350 logCHCD-f-0.750
AOs
(pphn
'20
10
5
1
0.5
0.1
)
•
•
-
51"
1
&
71
31
33
J
35
57
f ^_
^R
50
66
0.
32
^
«d
34
3
6
ft
26
30
26*
•5 2
la*J
4U
124
46
•39
37
•
61
•
•4V
zs
-
•
0.5 1 5 10 20
NMHC
(pphm)
Fig 4. 3.4(2) Correlation .between NMHC and AQgCNOx 2.0~ 4.9 pphm)
208
-------
logCAQ, 3 = 0.296 logCHCD + 0.868
AOs
(pphn
20
10
5
1
0.5
0.1
)
•
.
•
*"'
i
Zi
n
33
60
T -
= (
66
1.3
53
.10
•30-34
.1
.«
65*
25
36
18
-
.
-
62
*
.4
9^
*
7
,,
•
0=1 5 10 20
NMHC
(pphm)
Fig 4.3. 4(3) Correlation • between NMHC and AQ, (NOx 5.0~-9.9pphm)
209
-------
iogCAO, 3 = 0.164 logCHCD+l.l 67
AOs
Cpphn
20
10
5
1
0.5
01
)
,
*
»
»
•
17
r
•
=
0.
z<
38
8
23
'16
IS .
.if
21
19
-
*
•
13
zz
•
-
X
0.5 1 5 10 20
NMHC
(pphm)
Fig 4.3.4(4) Correlation between NMHC and A03 (NOx lO.Opphm)
210v
-------
D=0.771 logCNOxD + 0.245 (1)
AOs
(pphn
20
10
5
1
,
•'
r
•
=
0.!
}'
/
r 9**
•
73
"/
/
•
/
f
/
SI
-
'
/&
/
/
27
•
S
U
/
s
•
*/
•
%
^21
13 1
S
S is
1 5 10 20
NOx
(pphm)
Fig 4 3.5(1) Correlation between NOx and "AO* (HC/NOx 0~10)
211
-------
logCAOg } = 0.684 log C NOX J+0.299
AOs
(pphir
20
10
5
1
)
"
'-
.
•»
-
/
'
'
r
'
o:
7
/
76 1**
\J^
•
• (
st-i
53
•58
3
0
'
.
/
35 (
"68
• r
/
•(
7
•
q
.(
/
6
33
'
0 f
S
.
25
•
/
56
^
*
6
41
,12
8
/
S
•L:
•
*
•14
/
~
1 5 10 20
NOx
(pphm)
Fig 4.3.5(2) Correlation between NOx and AQ,(HQ/NOx Il~l8)
212
-------
0.503 logCNOg 3 + 0.491
(pphn
20
10
5
1
)
"
*,
i
•
u.
4
U /
•55
•
•
. .
.31
38.
Jl
>0«
24 *
26*
64-
32
5
'4
* Zv
36'
34
.1
18'
•
'
*
22
'
1 5 10 20
NOx
(pphnO
Fig 4.3.5(3) Correlation .between NOx and AQj (HC/NOx 19-28)
.213
-------
3 = 0.898 log CNOX3-I-0.276
AOs
(pphn
20
10
5
1
)
•
•
/
/
•48
,
'
i
'
/
- V
'
I.I OO '
• 52
/
/
44
* 0(
•45/
/4,
•43
/
/
46
,
4(
aa *
^x
28 3'
•
•2
47
*3
>
/
•i
^
1
.
/
,
x
*
/
X
x
•
1 5 10 20
NOx
Cpphm)
Fig 4.3.5(4) Correlation between NOX and AQ,(HC/NOx 29-)
214
-------
In this case multiple regression equation was assumed to exist, so that the
following multiple regression equation model was employed to carry out multiple
regression analysis:
[A03] = a[NOx]e • [HC]Y
Taking common logarithm of both sides, we obtained
log [A03] = loga+ e log [NOX] + y log [HC]
to calculate a, e, and y by method of least square.
The value of ACL corresponding to NOV and HC in all experiments was plotted
o x
as shown in Fig. 4.4.1.
Making NO and HC variables, we can obtain the following multiple regression
A
equation with respect to ACL;
[A03] = 2.347 [NOX]0'652 [HC]0-119, (r = 0.774) (4.4.1)
Unit of A03; pphm
Unit of NO ; pphm
/\
Unit of HC; ppmC
Further we obtained the correlation between the actually measured value of
A03 and UV Dose (UV intensity x irradiation time) and UV intensity that were
assumed to be correlated with the ratio of measured A03 to A03 calculated by
the above equation. The caluclation showed that UV intensity had closer correla-
tion than UV Dose. Thus adding the UV intensity as the next factor, we obtained
the follwoing multiple regression equation. However it did not show a satisfactory
multiple correlation factor.
215
-------
[A03] = 1.671 [N0x]0'687 [HC]°-0971 [UV]0-149 ( = 0.777) (4.4.2)
Unit of A03; pphm
Unit of NOX: pphm
Unit of HC : ppmC
Unit of UV : mW/cm2
Thus we substituted the initial value of NO and NMHC into equation (4.4.1)
A
to calculate A03- The ratio of that calculated value to actually measured one
is shown in Fig. 4.4.2 Also we substituted the initial value of NO and NMHC
J\
and the UV intensity into equation (4.4.2) to calculate AOo, the comparison of
the calculated value to measured value being shown in Fig. 4.4.3.
When the measured value of ozone to the calculated one in these two figures
is compared with each other, the equation (4.4.2) shows better correlation in
the range of low concentation.
Next we summed the olefinic and aromatic hydrocarbon components that were
believed to be reactive, and used this sum in lieu of total hydrocarbon in the
multiple correlation analysis.
The resultant regression becomes as follows:
[AOJ = 2.599 [NOl0'573 [A + o]°'180 (r = 0.769) (4.4.3)
O J\
Also the use of aromatic hydrocarbon, except benzene, as a factor gives the
following equaiton:
[AOJ = 2.634 [NO!0'571 [A + 0 - B]°'175 ( 0.768) (4.4.4)
j X
Referring to the equations (4.4.3) and (4.4.4) the comparison of the calcu-
lated value to the measured one was obtained by the same way as the previous
one. They are shown in Figs. 4.4.4 and 4.4.5.
216
-------
NOz
040
025
0.20
0.15
0.10
04 S
26.1
.204
1 6.4
v.
•16.4
,90
C AO, D-^34 7CNOi
.25.5
-0.15ppni
'"CHCD*
u
2.0
3.0
NMHC
Curve showing correlation between NOx.HC and A03
217
-------
Measured
AQjV.lu
(pphra
25
20
IS
'
to
s
0
-
2«
»
42
' 35 "*
.52*18 /
ny& ;
*»*// *v43 *
^X^ **44
X "- •"•
CAOj 3 = 2.347CNOx3
4
f 30 34
33
2
• 17
#
S
*
f '•"-' '' /'''
* • X
* X
MX/ .
/X .**
/?.!*'
' *'** f "
Jl
82
«4
l"fHcf"(R=0.774)
9
»
'
7
IZ
•
0
/
s
X
/
19
*
*
•
/
/'
" xxi
X •
1«
•
13
X
/
X
*
.5 10 IS 20-
Heuured aO, Value
Fig 442 Calculated value and Measured value of
218
-------
Me.surtd
(»hnO
25
IU.1* OOTTl 0KB
CAO, 3=1.6707CNOx(j CHCJ CUV3
( R=0.7 77 )
20
15
10
» 30
•33
/
58 50
Ait*
v
.><"
'» •«
S 10 IS
Fig 443 Calculated value and Measured value, of A03
20
Measured A Oj VxlueuC pphm )
. 219 •:
-------
Meuurni
AQjV.lu.
(pphm)
25
C AO,
f
C A + o 3~"
(B-0.769 )
ft*
20
15
10
3» 3S
• 45
* "/
S
/ **
/ Ml
«4
0 S » 10 15
Fig 4 4 4 Calculated value and Measured value of A03
20
Ueuund AO, Value (
220
-------
Measured
AQ,V»Ui
(ppta)
25.
20
IS
10
s
40
•
M
•42
/.
J* JIX
73 ***/ 4J
*4* */43
? «
/ .« ?
CAO, 3-2.6 34 CNOxT
•
12
•
X
4T XX
• X
w /x
/
ft *«s
.61
62
1 0175
CA + 0 - Benzeti]
(R=0.7«8 )
.
14
xx
X
'
^
X
w
13 X
/
/
X
0 5 10 IS
Fig 4 4 5 Calculated value .and Measured value of
2.0
Ifeuured AO3 Valu, ( pphm)
221
-------
The comparison between these figures and the two previous ones shows that
the ratio of the measured concentration of ozone to the calculated one becomes
better in the low concentration ragne.
The comparison between equations (4.4.3) and (4.4.4) and equations (4.4.1)
and (4.4.1) and (4.4.2) shows that the multiple correlation coefficient hardly
changes so that the correlation can not be said to be improved,'but equations
(4.4.3) and 4.4.4) have higher exponent with respect to HC so that the quantities
of high activity olefins and aromatics in NMHC should be still taken into consid-
eration when HC is assuemd to be a factor for AO.,. As shown in Fig 4.4.2,
Kawasaki (in winter 1973) and Kamata areas provided more experiments in which
the ratio of the measured value to the calculated one of AO, was at least 1.5,
and Kawasaki (in summer 1973) and Oymazaki areas provided more experiments in
which the ratio was less than 0.75. These were considered to be caused by the
difference between local air pollutants, in particular, the difference between
hydrocarbon compositions or experimental conditions, especially the variation of
ultra-violet light intensity. However we are not sure of these causes.
5. Summary
By representing AO., as the function of NO , HC, UV intensity, A + 0, A + 0-
benzene, etc. we attempted to establish the basis for quantitative decision and
obtained a tentative result from the above-mentioned statistical analysis.
As a result, NO was found to be the most important factor as a substance
/\
related to the formation of ozone according to single correlation analysis.
However the formation of ozone could not be sufficiently explained only by NO .
A
Thus, according to multiple correlation analysis reactive olefins and aromatics,
except benzene, was found to be the 2nd factor. Also we carried out the multiple
correlation analysis, adding UV intensity that, however, was insignificant
factor. This seemed to be caused by uncertain data (value measured by a ultra-
violet light sensor provided in the chamber)
222
-------
Also in view of experiments in which the difference between the measured
value and the calculated one of 0, was large, the causes of this difference
should be examined by future investigation.
At last, the following should be performed:
(1) to carry out many experimental and analytical experiments in one area,
(2) the same method should be employed,
(3) to improve the accuracy of HC composition analysis,
(4) to carry out experiments in aras having large and small HC/NO
X
(5) to establish and standardize the method of measuring ultra-violet light.
Also referring to the statistical analysis, it is believed that there is
room for further examination to be applied to the classification of data, the
selection and combination of factors, other multiple regression models,
etc.
223
-------
Health Hazards of Photochemical Air Pollution
(The results of a survey on health hazards of
photochemical air pollution in 1975) — Japanese Delegation
March 1976
Air Quality Bureau,
Environment Agency
i
224
-------
I, Preface 1
II. Overall Analysis 1.
1. Introduction 1
2. The state of photochemical air pollution in Japan in 1975 3
3« Method of Surveying 10
2-3-1 The method employed in the present survey 10
2-3-2 Brief description of the effects on human health 10
2-3-3 Places where photochemical smog victims occure 19
and the effects of physical exercises
2-3-4 A pilot study on the constitutional disposition of 25
the reported victims of photochemical smog
2-3-5 Serious cases of phochemical symtons 28
2-3-6 Correspondence "between environmental conditions and 32
reported cases of photochemical smog victims
4« Conclusion 36
11
225
-------
I. Preface
In Japan the photochemical air pollution has become a serious
social problem since the incidents that occurred in the ^western
coastal areas of Chiba Prefecture in June 1970 -and at the Rissho
Senior High School in July of the same year. Since then, various
surveys and investigations have been made on photochemical smog
hazards. Since 1972, the Photochemical Air Pollution Investigation
Committee of the Environment Agency has been conducting a comprehensive
research and investigation on the conditions for causing photochemical
smog, the incidence of the particular air pollution, and.its effects
on human health. As for the effects on human health, the subcommittee
for health survey of the above-mentioned- committee has been conducting
various surveys.
The 1975 survey on the effects of photochemical air pollution on
human health was carried out to investigate the effects of photochemical
air pollution on human health, thereby to make further advances in this
country's public health preservation measures on the basis of the
results of all the surveys conducted previously. This report gives
the results of an analytical study of the reports submitted to the
above sub-committee from seven prefectures where surveys were carried
out.
II. Overall Analysis
1. Introduction
This chapter is a summary of the results of the analytical study
- 1 -
226
-------
the working groups set up in the photochemical air pollution health
hazards investigation subcommittees in seven prefectures had made
a study of the following points on the basis of the reports submitted
to those subcommittees.
a) To make a study on the contents of the received reports on
damage to health by photochemical air pollution, particularly
the points common with all of them, thereby to make clear the
effects of photochemical air pollution on human health.
b) To make a case study to investigate the condition of the
victims and the environmental conditions on the day a mass
incidence of photochemical air pollution symptoms was
reported (on such days as June 6 and July 18 in Kanagawa
Prefecture and July 15 and July 16 in Saitama Prefecture,
for instance).
c) The previously made studies revealed that the constitutional
factors of individuals must be taken into consideration
when making a study on the effects of photochemical air
pollution on human health. As a pilot study, the results
of surveys conducted in Osaka and Ifycgo Prefectures will
be studied.
d) To make a clinical study on the serious cases (victims
hospitalized) which occurred on July 18 in Kanagawa Prefecture.
*
e) To study the relationship between environmental considitions
and incidence of sufferings from photochemical air pollution
on different days, that is, the day when the "photochemical
- 2 -
227
-------
smog alertn is not issued (oxidant concentration in the air< 0.15ppm)>
the day when the alert is issued (oxidant concentration > 0.15ppnO,
and the day when the "alarm" is issued (oxidant' concentration >
0.30ppm in Kanagawa Prefecture and > 0.25ppm in Saitama Prefecture).
f) In order that the results of the 1975 survey on the health
hazards of photochemical air pollution may be duly reflected
in the public health preservation measures to be taken in the
future, a careful study will be made from the standpoint of
experts and of the prefectural governments which undertook
the survey and the Environment Agency and further efforts
•will be made to clarify the problems to be dealt with in
the future.
2. The state of photochemical air pollution in Japan in 1975
This section is devoted to the study on the environmental
conditions and the reported cases of sufferings from photochemical
air pollution throughout Japan, thereby to make clear the positions
of the abovementioned seven prefectures in the nationwide situation
of photochemical air pollution.
The numbers of oxidant" warnings issuances and photochemical
smog victims are summarized in Tables 2-2-1 through 2-2-4.
From these data, it may be said that the photochemical air
pollution "during 1975 had the following characteristics.
a) About 58$ of the total reported cases of sufferings from
photochemical smog occurred on the days when the oxidant
alarms were issued (June 6, July 15 and 18, August 13).
-3 -
228
-------
Particularly, in Saitama Prefecture, as many reported cases
as 84$ occurred on July 15 alone and about 98$ x>n June 6
arid July 15 in Kanagawa Prefecture. However, there was a
case in which the number of reported victims was very small
even on the day when the photochemical smog alarm- was issued
as it occurred in Saitama Prefecture (August 13). It was
presnmably due partly to the fact schools were closed on
August 13 because of summer vacation. There might have been
some other unknown reason for such a singularly small number
of reported photochemical smog victims on that particularly
day and a further study is necessary to solve this problem.
b) Looking at the numbers of reported photochemical smog victims,
the number of reported victims was issued was greater in the
eastern part of Japan than in the western part, that is, 98$
of the total reported victims (42,839) was issued in Japan
east of Mie Prefecture while the corresponding figures were
very small in the Kansai region and the areas along the shore
of the Inland Sea. Investigations were made on the causes
of this phenomenon, including the meteorological conditions,
but nothing is not known for sure. It is notable that the
frequency distribution of oxidant alert and alarm issuances
agree with the distribution of the numbers of reported
victims in Table 2-2-1.
c) A photochemical oxidant level as high as 0.39ppin was detected
- 4 -
229
-------
in Isogo of Yokohama on July 18, the highest concentration
of oxidant in the air ever recorded in Japan.
From the above nationwide characteristics of photochemical air
pollution, it is possible to have a general idea of the situation in
the prefectures where the present survey was conducted as"follows.
In Saitama and Kanagawa Prefectures, very high percentages of
reported cases of photochemical smog victims occurred on the days
when the alarms were issued (over 0.25ppm in Saitama Prefecture and
over 0.30ppm in Kanagawa Prefecture). In Hie Prefecture, the number
of reported cases of sufferings photochemical smog was greater than
in the preceding year in spite that no "alert" was issued. (In Mie
Prefecture the photochemical smog alert is issued only when the oxidant
levels are found exceeding 0.15ppm when measured at two photochemical
oxidant monitoring stations in the area concerned while the alert is
issued when the oxidant level exceeds 0.15ppm at a single monitoring
station in other prefectures.) In Osaka, Hyogo and Okayaraa Prefectures,
the "alerts" were issued but the number of reported victims greatly
decreased from the preceding year. There was no reported case of
suffering from photochemical smog is Hiroshima.
- 5-
"230
-------
Table 2-2-1 Oxidant alerts issued in 1970 - 1975
( ). Bracketed .are "alarms'1
10
"~ — ~~"-— - -J[?a_r
Prefecture ^ — _
Tohoku I Miyagi
Region Fukushima
Kanto
Region
Chubu
Region
Kinki
Region
Inland Sea
districts
Ibaraki
Tochigi
Guirana
Saitama
Chiba
Tokyo
Kana^awa
Shizuoka
Aichi
Mie
Shiga
Kyoto
Osaka
Hyogo
Nara
Wakayama
Okayaraa
Hiroshima
Yamaguchi
Tokushima
Kagawa
Ehime
Total
1970 1971
23
19
7 33
11
1
4
7
7 98
1972
16
15
21
33
31
5
4
7
18
19
1
1
3
176
1973
3
21
10
1
. 45
28
45
30
&
8
6
4
17
26(1)
23
6
1
14
9
1
22
328(1)
1974
14
10
4
29
26(1)
26(1)
26
15
2
7
4
17
27
19
3
1
16
18
5
2
4
•13
288(2)
1975
3
17
6
11
44(2)
33
• 41(1)
27(2)
16
6
4
11
23
11
9
5
4
1
2
1
1
266(5)
-------
Table 2-2-2 Oxidant alerts issued in 1975
to
U)
N>
Prefecture " —
Tohoku
Region
Kanto
Region
Chubu Region
Kinki Region
Inland Sea
districts
Miyagi
Fukushima
Ibaragi
Tochigi
Gumma
Saitama
Chiba
Tokyo
Kanagawa
Shizuoka
Aichi
Mie
Shiga
Kyoto
Osaka
Hyogo
Nara •
Wakayama
Okayama
Hiroshima
Yamaguchi
Tokushima
Kagawa
Ehime
Total
Apr. May
1
1
2
3
2 3
3
2
2
1
1
2 ' 19
' June
1
8
4
7
5(1)
1
5
8
3
1
2
1
1
47(1)
July
1
6
3
3
13(1)
7
6(1)
3(1)
2
4
2
4
7
3
5
2
1
72(3)
Aug.
1
5
1
6
13(1)
11
11
8
2
2
3
5
1
1
1
68(1)
Sept. Oct.
1
4
1
2
8
7 1
11 1
6 2
1
2
1 1
4
2
2
1
1
1
53. 5^
Total
0
3
17
6
11
44(2)
33
41(1)
27(2)
6
6
0
4
11
23
11
9
0
5 '
4
1
2
1
1 •
266(5)
(Note) Bracketed are "alarms".
June 6: Kawasaki, Kanagawa Pref. (0.32ppm)
July 15: Shakujii, Tokyo (0.31ppm) Fujimi.-Saitama Pref. (0.33ppm)
July 18: Yokohama, Kanagawa Pref. (0.39ppm)
Aug. 13: Fujimi, Saitama Pref.
-------
Table 2-2-3 Reported victims in 1970 - 1975
Prefecture ~~~ — — - — ______
Tohoku Region
Kanto Region
Chubu Region
Kinki Region
Inland Sea
districts
Miyagi
Fukushima
Ibaragi
Tochigi
Gumma
Saitaraa
Chiba
Tokyo
KanaRawa
Shizuoka
Aichi
Mie
Shiga
Kyoto
Osaka
Hyogo
Nara
Wakayama
Okayama
Hiroshima
Yaraaguchi
Tokushima
Kagawa
Ehime
Total
1970 1971
1972
1973
1974
1975
31
1,262 3,663
5,923 1,169
10,064 28,223
638 13.183
277
1,600
3
17,887 48,118
728
5,726
561 .
8,439
1.383
716
231
13 •
1,640
430
150
136
1,167
21,320
207
776
6,774
155
4,035
2,526
8,278
330
1.148
16
599
3,122
989
27
102
2,470
367
4
31,936
17
38
1,498
237
2,711
941
162
151
630
1
774
4,373
7
'523
2,660
2
14,725
31
23
1,959
16,624
277
5,210
8.255
6,345
1,787
1.786
1
79
290
62
4
75
42,839
I
oa
I
to
LO
OJ
-------
Table 2-2-4
~ — — __Month
Prefecture " ___
Tohoku
Region
Kanto Region
Chubu Region
Kinki Region
Inland Sea
districts
Miyagi
Fukushima
Ibaragi
Tochigi
Gumma
Saitama
Chiba
Tokyo
Kana^awa
Shizuoka
Aichi
Hie
Shiga
Kyoto
Osaka
Hyogo
Nara
Wakayama
Okayama
Hiroshima
Yaraaguchi
Tokushima
Kagawa
Ehime
Total
Apr. May June
38 1,926
69 25
1 1,208 1,132
4.931
33 14
38
5 6?
50
i
4
18 56 1
19 1,409 8,188
July
1
18
23
1,857
14,485
183
2,652
3.253
6,345
1,728
269
1
48
212
11
31,086
Aug.
102
101
49
35
4
1
292
Sept.
t
30
13
74
167
2
8
1.479
3
6
1,782.
Oct. Total
0
31
31
23
1,959
16,624
277
1 5,210
34 8.255
6,345
1,787
1,786
1
28 79
290
62
0
4'
75
0
0
0
0
0
63 42,839
to
03
(Note) Reported victims on the days the "alarms", were issued.
June 6 Kanagawa Pref. (4,853)
July 15 Tokyo (2,557) Saitama Pref. (14,032)
July 18 Kanagawa Pref. (3,227)
Aug. 13 Saitama Pref. (1?)
-------
3. Method of Surveying
2-3-1 The method employed in the present survey
The basis method of surveying was described in Chapter 1.
The concrete method differed -with the prefectures where the survey
was conducted, for those prefectures had so far been undertaking
their own surveys on the health hazards of photochemical air
pollution.
The methods of surveying employed by the respective prefectures
are summarized in Table 2-3-1. In studying the survey results, such
differences in the surveying methods used by different prefectures
were taken into consideration and the common and characteristics
points were summarized.
2-3-2 Brief description of the effects on-human health
The survey results reported from the prefectures concerned
were tabulated and their common points and differences were
reviewed.
a) The numbers of people on whom the survey was conducted and
the numbers of reported victims broken by sex are given in
Table 2-3-2. There was no reported victim in Okayama and
Hiroshima Prefectures,' therefore, omitted from the following
analytical review.
From this table, the following points can be confirmed.
* There" was little difference in number between male and female
reported victims, except for Osaka Prefecture where male
victims accounted for 61.7% of the total.
- 10 -
235
-------
It was previously said that the number of reported cases of females
suffering from photochemical smog was larger than that of males but this
tendency was not confirmed by the -results of the present survey..
* Junior high school students accounted for the largest proportion
of the reported victims. In Saitama Prefecture, 52.1$ of the
junior high school students under survey reported on their sufferings.
About two-thirds of the reported victims were junior high school
students in Kanagawa Prefecture.
b) Places where the reported cases occurred
The numbers of reported cases which occurred indoors and outdoors is
shown on Table 2-2-3- It was previously said that there was a larger
number of reported cases of sufferings occurring out of doors and
the school students were told to remain indoors when the photochemical
"smog alarm was issued. The results of the present survey revealed
that there was considerable numbers of people suffering from
photochemical smog even when they were staying indoors.
Particularly, in Kanagawa Prefecture more than two-thirds of
the total reported cases complained of sufferings from photo-
chemical smog. Therefore, it may be said that there is practically
no difference between the inside and outside of houses in the
summer when the doors are usually kept open.
-J.1 -
236
-------
Table.2-3-1 Methods of surveying employed in the seven prefectures
Prefecture
•Schools designated
for surveying
Response to
questionnaire
Tims of filling
out the question-
naire
Remarks
4 elementary
Saitama schools (Over third-
year students)
4 .junior high
schools
2 senior high
schools
The students filled Filled out not
• out the question- later than the
naire themselves day after the
occurrence of
damage.
Questionnaire A was filled in by the
students themselves. As for the
students who complained of physical
disroders and were taken into the
rest-room, nurse-teachers and school
doctors made clinical examinations,
checking their symptoms and medical
history in compliance,with
Questionnaire B.
K) |
W
Kanagawa
Hie.
No designated
school
The students filled Same as above
out the question- .
naire themselves.
3 elementary
schools
2 junior high
schools and
Daian Junior
High School
Surveyors
interviewed
students to fill
in the questionnaire
(except Daian
Junior High School).
Same as above
Questionnaire was conducted on the
schools where more than 10 students
complained of physical disorders on
June 6 and July 18 when the "photochemical
smog alert" was .issued. However, the
schools went into summer vacation on
July 18 and therefore it was impossible
to collect all the answers to the
questionnaire.
June 6: 5 elementary schools, 8 junior
high schools, 4 senior high schools
July 18: 1 elementary school, 5 junior
high schools, 2 senior high schools
At Daian ElementaryvSchool, a method
different from other schools was used,
that is, questions were asked to the
students and they answered by raising
their hands.
-------
All public elementary
and junior high
Osaka schools in Osaka
Prefecture (ex-
cluding those in the
cities of Osaka and
Sakai)
Okayama
to
w
CO
Surveyors inter-
viewed students
to fill in the
questionnaire.
Public elementary
Hyogo schools (over
fourth-year students)
and junior high
schools in the
designated areas.
Same as above
15 elementary
schools,
7 junior high
schools and
2 senior high
schools
Same as above
Hiroshima 8 junior'high
schools
Students filled
in the question-
naire themselves
(Unknown)
(Unknown)
Filled in on the
day of occurrence
of damage
The first survey was conducted, using
the ordinary questionnaire. After
October, the secondary survey was
conducted on orthostatic disorders
and blood pressure to make investiga-
tions on the constitutional dis-
position of the affected students.
The number of the reported cases was
so small during 1975 that health
survey was conducted on the reported
victims of 1975 and 1974 to make
investigations on the personal dis-
positions of the reported victims.
There was no reported victims at
these disignated schools.
Same as above.
-------
Table 2-3-2 The numbers of people under survey and the numbers of reported .victims, classified by sex
10
U>
^s"
° §
n
K%.m
°«
fetl
IB
K t. >
— Prefecture ' Saitama ' Kans
—
Slementary
school students
Junior High
school students
Senior High
ichool students
Adult people
fTbtal
Elementary
school students
Junior High
school students
Senior High
school students
Adult people
Tbtal
Reported victims
classified by sex (59
§•*
-------
Table 2-3-3 Places where the reported cases occurred
"~— — -^.^Pref e cture
•o «>
« ft
•e i
M O
O O
§•0
w ^^
JH
MO
n > n
£4 (4
0> 8) O
J 3 e
S3 O -H
•a*
« 2
t &
ao
0
£f\
0
Elementary
school students
Junior High
school students
Senior High
school students
Total-
Elementary
school students
Junior High
school students
n "§ Speni°r High
fe «, 2i school students
07 09 ^x
1 11
S5 0 O
Total
i
Unknown Total
Saitama
67
Kanagawa Mie
i
Osaka
-
528 72
i m '.
862 2,479 ' 59
(299)
71 217
j ;
1,000 3,224 131 52
131
1,148
59
1,338
)
409
938"
116
62
(62)
114
17ft
1,461 (178)
i
0
110
9
_
•
-
26
0
Hyogo
-
-
-
44
_
-
-
18
0
Note) According to the survey conducted in Saitaraa Prefecture,
most o'f the reported cases of indoor victims (elementary
school students 98^, junior high school students 92.6$
and senior high school students 97.1#) occurred when
the windows were kept open. It was presumably the
same with the reported cases of indoor victims in other
prefectures. Bracketed are the figures including the
students of Daian Junior High School in the case of
Mie Prefecture.
"240
-------
Table 2-3-4 Physical exercises and photochemical smog damage
\~~ ~~~ — : — — ___ftref e ctur e
L exercise
(-0
-------
c) Physical excercises and photochemical smog damage
The numbers of reported victims occurring when they were taking
some forms of physical exercise or not engaged in any form of
physical activity is shown .in Table 2-3-4.
The tabulation of the questionnairing results have been completed
only in Kanagawa'ahd Osaka Prefectures. Thus obtained results
show that there occurred many cases of victims among the students
not engaged in physical exercises. However, considering the
fact that when one is taking a physical exercise one breathes
in more air and consequently more air pollutants than when not
engaged in a physical exercise, it is considered necessary
to make a more detailed study on this question in relation to '
the degree of intensity of physical movement in such exercises
. and the- subjective symptoms of the photochemical smog victims.
d) Subjective symptoms (Table 2-3-5)
Table 2-3-5 shows the percentage proportions of the total
symptoms reported by the photochemical smog victims.
The most common subjective symptoms due to photochemical smog
are the eye, nose and thread mucous membrane irritations, which
account for about 50j£ of the total. Apart from the above, there
are respiratory, circulatory and general symptoms (including
neurotic symptoms). The reported cases of general symptosm
(including neurotic symptoms) were nearly equal in number to the
mucous membrane irritation symptoms.
e) The ratios of subjective symptom complaints to the reported
- 17 -
242
-------
victims of photochemical smog (Table 2-3-6)
Table 2-3-6 shows the ratios of subjective symptom complaints
to reported victims in the various categories of symptoms.
About 50 to 90$ of the reported victims complained of eye, nose
and throat symptoms in other prefectures than Osaka. In Kanagawa
Prefecture 87.9$ of the reported victims complained of eye symptom.
Further details of the respective symptoms in the case of Kanagawa
Prefecture are given in Table 2-3-7. The complaints of general
symptom were so many as 62.9$, 40.7& 49^ in Kanagawa, Mie and Osaka
Prefectures, respectively, suggesting the necessity for further
investigations in the future.
f) Health preservation measures taken for the photochemical smog
victims (Table 2-3-3)
The questionnaire results have been tabulated only in Saitama
and Mie Prefectures. According to the tabulated relies to this
particular questions, most of the victims "washed their eyes
and gargled their throats" or "did nothing". There was no one
who "received medical treatment from a doctor" or "was hospitalized"
in either of the two prefectures. Although not given in this
table, there were hospitalized cases in Kanagawa Prefecture on
July 13.
In Mie Prefecture the students who "left school earlier"
accounted for 16.6$.
Such a high percentage was ascribable to the fact that all of
the 220 reported victims at the Daian Junior H^gh School left
school early.
- 18 -
243
-------
g) The time required for the victims to recover (Table 2-3-9)
As in the case of the above f), the tabulation has been completed
only in Saitama and Mie Prefectures. According to those tabulated
questionnaire results, the majority of the victims recovered at
schools or in their homes within the same day. However, the
victims who "went tp school although not completely recovered on
the following day" and who "were absent from school on the following
day" accounted for about 6% and slightly less than 1>S, respectively.
This fact is notable in relation to the serious damage caused to
health by photochemical air pollution and it is a subject which
requires further investigations in the future.•
2-3-3 Places where photochemical smog victims occure and the effects
of physical exercises
- To make clear the effects of photochemical sicog according to
the places where the victims occure and whether they are engaged in
physical exercises is important in working out effective protective
measures against the hazardous air pollution.
It was notable that the results of the present survey showed
that the percentage of the victims remaining indoors (windows were
kept open in most cases) was fairly high. The simple tabulation of
the questionnaire results showed no distinct difference in number
between indoor and outdoor victims and between the exercising and
not exercising victims.
In order to study the effects of such factors on the incidence
-19 -
244
-------
of sufferings from photochemical smog, it is not suffice simply to
make clear the percentage proportions of indoor and outdoor victims
and the exercising and not exercising victims. It is necessary
to make a more detailed study, including the ratios to the popula-
tions of the respective groups of victims
and the time factors '(relationship to the level of contamination)
to be discussed later.
A survey' conducted on the students of the Mihashi ' Junior
High School in S,aitama Prefecture on July 15 showed little disparities
in the ratio of reported victims, difference between male and female
and symptoms according to the school years. However, as seen from
Fig. 2-3-1, there were obvious time disparities for the ,students to
complain of physical disorders, that is, many third-year students
complained of photochemical smog symptoms earlier when the Ox level
was still not very high. In this district the photochemical smog
alert was issued at 11:00 and the alarm at 12:15 and the Ox concentra-
tion in the air reached its peak at 13:00 when measured at the municipal
office of Ondya situated near the junior high school. On the other
hand, about one-third of the first- and second-year students were
taking gymnastic lessons in the gymnasium and the rest were taking
lessons in their classrooms. This particular case is considered
suggestive of the fact that physical damage caused by photochemical
smog varies according to whether the victims are within or out of doors
or whether they are engaged in physical exercises.
A further"detailed study, is necessary to be made on the effects
- 20 - 245
-------
of such factors on the occurrence of photochemical smog damage to
human health.
Table 2-3-5 Reported subjective symptoms
<*)
Prefecture
Symptom
Saitama Kanagawa / ;Mie
Osaka Hyogo
Eye symptom
1) 24.4
Nose and throat symptom
2) . 20.7
Respiratory symptom
3)
Circulatory
symptom
(Including~5eurc^c-3
symptom)
Others
28.5
25.7
0.7
28.3
35.6 38<# 24.9 55.4
(36.3)
24.9
(28.0)
11.0
(-16.0)
14.4
17.7
20.3
3.1
26.1
33.0 (19.7) 33.4 > 24.3
0.0 0.0 9.8 ]
(0.0) *>
Remark
Total number of
reported symptoms
11,476 599 153
(1,166)
Bracketed figure
include the
victims at Daian
Junior High School
Note)Detailed description of symptoms complained by the photochemical
smog victims
1) Feel pain in the eyes, eyes are irritated and smart and tears flow.
2) Noses are irritated, run, voice becoras hoarse, throats are irritated,
noses sting, sneeze, noses feel itchy, noses bleed. .
3) Cough, feel opfessed in the chest, feel choky, chests pain, cough up
phlegm.
4) Hearts pound, feel the sense of constriction in the chest.
5) Feel the numbness of the extremities, feel foggy, feel dizzy,
have headache, feel nausea, feel pain in the extremities, feel
languid, feel feverish, feel sick.
-------
Table 2-3-6 Ratio of reported subjective symptoms to the reported victims
I
JO
to
— -^^ftreftet^^
Eye symptom
Nose and throat symptom
Respiratory symptom
Circulatory symptom
General symptom
(Including neurotic symptom)
Others
Remarks
Kanagawa Mie Osaka
87.9* 67.5* 38*
(75.8*)
44.1* 27*
(58.6*)
69.9*
19.5* 33*'
(33.5*)
7.8*
81.5*' 46.2* 63*
(41.3*)
19*
Brocked figures include
the victims at Daian
Junior High School
-------
Table 2-3-7 Detailed description of reported subjective symptoms
(From the survey on photochemical smog damage in
Kanagawa Prefecture on June 6)
Eye symptoms 87.9%
Irritated 43.0
Pain 31.4
Smart 28.9
Tearing 24.9
Respiratory symptoms 69.9
Throat irritation 43.0
Coughing 29.1
Feel thirsty 27.1
Feel choky 24.5
Feel pain in the chest 16.2
Circulatory symptoms 7.8
Thumping of the heart 5.1
Feel opressed in the chest 3.5
General symptoms 62.9
Feel languid 48.0
Headache 42.6
Feel feverish 2.8
Neurotic symptoms 18.6
Feel foggy 16.5
Numbness in the extremities 2.5
Convulsions 1.4
- 23 -
248
-------
Table 2-3-8 Protective measures taken for the photochemical smog victims
Saitama"Pref. Mie Pref.
o
o
o
o
o
o
o
Washed eyes and gargled
Remained quiet in the classrooms
Kept quiet in the rest-room
Received medical care from doctor
Left school early
Taken into the hospital
Others
69.6*
12.3
1.1
0.0
0.1
0.0
17.1
19.42
(42..7J0
-
1.9
(1.0)
0.0
(o.o)
0.3
(16.650
0.0
(4.0)
78.4
(39.7)
Note) "Other" include "Did nothing".
Table 2-3-9 The time required for the victims to recover
Saitama Pref. Mie Pref.
o
o
o
o
Recovered at the school
Recovered after coming home
Went to school although not
recovered until the next day
Did not go to school on the next day
24.42 1
I
|
68.1 J
6.5
0.7
93.82
(85.42)
5.9
(14.2)
0.3
(0.4)
Note) Report from other prefectures.
The bracketed figures for Mie Pref. include the cases at the
Dian Junior High School.
- 24 -
249
-------
2-3-4 A pilot study on the constitutional disposition o
reported victims of photochemical smog
It has been found that the majority of the serious v:
themselves and the members of their families previously s
such allergic dieseases as drug rash, nettle rash, contra
dermatitis, allergic nasitis and asthma. The survey cond
1974 has revealed that the group of students suffering fn
disorders (O.D.) showed different patterns of subjective ;
other ordinary students both at the time of photochemical
the normal time.
Surveys were conducted, paying attention to the consi
of the victims were conducted in Osaka and Hyogo Prefectui
results of those surveys will be summarized below.
As for the group of students of alergic disposition,
Prefectural Association of Medical Practitioners made a cc
study of those who complained of photochemical smog symptc
those who made no such complaints and reached the conclusi!
there was difference between them. However, it must be no
the highest oxidant level measured in Hyogo Prefecture was
in the town of Taishi in the two years of 1974 and 1975 an:
ocidant level was relatively low in other parts of the pre
And the number of reported cases of photochemical smog dam
relative small and therefore it was impossible to make a t
.review on the relationship between the constitutional disp
and photochemical smog hazards.
- 25 -
250
-------
Surveys on the relationship between orthostatic disci
(O.D.) and reported photochemical smog symptoms were condi
in Osaka and Hyogo Prefectures. In Osaka Prefecture the i
•* •
was conducted only on those who complained of photochemicc
symptoms. In Hyogo Prefecture a comparison was made of ne
the same numbers of complaitants and non-complaitants. , Ir
Prefecture the O.D. group showed higher percentages of sue
complaints as "coughing" and "opressive feeling in the che
than the non-0.D. group. In Hyogo Prefecture the complain
12.9^ of positive O.D. reaction and the complaintants 6.8^
suggesting that there'is a close relationship between O.D.
photochemical smog symptoms.
Wiih regard to the surveys on photochemical sirog haza:
human health in relation to the constitutional disposition
be necessary to make further reappraisals of the surveying
and to make a comprehensive analytical study including the
and the degrees of seriousness of symptoms and also to con;:
relationship to the environmental conditions as a viewpoint
taken in making an analytical review.
The above-mentioned surveys conducted in Osaka and Hyo
Prefectures must be further developed with various improver
to be made to the surveying methods but they played a vain
as a pilot study.
- 26 -
_ „„_
-------
Ui
NJ,
Fig. 2-3-1 The times when the students of different school years first complained of photochemical smog -symptoi IQI
at the Mihashi Junior High School on July 15
m
o
T)
(O
0)
a.m " 10:00 11:00 12:00 13:00 H':00
20
10
„ First year students (344 compl<
tants
••' Second-year students (293 "
-v Third-year students (294 "
Ox concentration
(Omiya City Office)
f6*:66
Time unknown
-------
2-3-5\ Seriousnesses of photochemical symptoms
a) Subjects of survey
About 140 students of the Asahi Elementary School (with 1,510
students in total) in Tsurunri. Ward complained of obviously photo-
chemical smog symptoms in the afternoon of July 18 (Friday). The
measurements made at a feearby monitoring station showed 0.253ppni
of Ox, 0.042ppm of SOx and O.OlSppm of K02 when a south-southeasterly
•wind was-blowing at 3.6m per second. About 100 of the victims were
in the classrooas and about AO were out of doors, cleaning the swimming
pool. There were 28 serious cases and 11 of them complained of choky
feeling and numbness in the extremities and immediately taken by an
ambulance to a nearby hospital,, where they were given emergency
medical treatments such as oxygen inhalation and instillation.
As their conditions improved, four of them were allowed to go home
in the evening but the other seven students were slightly feverish
and stayed at the hospital overnight. On the next morning, they
all felt good again are allowed to go home at 10 a.m. We visited
five of the seven students at their home to make medical examination
and blood test.
T>) Results of medical examination
(l) Subjective symptoms: Eye irritation, throat irriation,
feeling of a foreign matter present in the throat, chocky feeling,
numbness in the extremities, feeling of fatigue and feverish feeling
were observed in almost all of the five cases. There was a case in
- 28 -
253
-------
which the victim complained of severe throat irritation and a cough
productive of blood-streaked sputum several times.
(2) Objective symptoms: When hospitalized, all of the five
»
victims were found slightly feverish (26.1° to 27.6°), had a an
increased frequency of respiration (31 to 42), reddened throatsflushed
faces- but almost completely restored their normal condition on the
next day.
(3) Past history of alergic diseases and family history
(Table 2-3-9): All of the five victims had a past history of alergic
diseases and four of them had their family members with a past history
of alergic symptoms, skin inflamation in most cases.
(4) Examination results: The serum.was separated within three
hours after the blood samples were taken and measurements were made
of the values of direct and indirect bilirubin, GOT, GPT, alkali
phosphatase and serum haptoglobin. As for the serum haptoglobin,
the separated serum was kept in frozen storage at -25°C and the
first and second measurements were made at the same time. Blood
tests were made on the day following the occurrence of the photo-
chemical smog symptoms and one week later. The test results all
showed normal values. The first and second tests showed almost
the same values of alkali phosphatase, which were higher than in
the case of adults and this was presumably related to the develop-
ment of bones.
c) Summary
The five hospitalized victims of photochemical smo& complained
- 29 -
254
-------
of mucous membrane irritation symptom, difficulty in breathing,
general symptoms and neurotic symptoms and showed such objective
symptoms as reddened throats., flushed faces and the rise of body
temperature. These cases showed close resemblance to the symptoms
of the serious hospitalized cases of photochemical smog victims
occurring in Japan since 1970 and the oxidant concentration was
so high as 0.253ppm on the day in question. In view of such
facts, these five cases belonged to the same category as the
previously reported serious cases. The rise of body temperature
and reddened faces were also observed in the above-mentioned five
cases and they are worth of note as the characteristic symptoms
of the serious cases in Japan. Blood-streaked sputum was observed
in a case in which the throat was seriously reddened.
It has been reported that the alergic people are more susceptible
to photochemical smog hazards and the seriously affected victims are
often found to have an alergic constitutional disposition. In the
case of the survey conducted on the students of the Asahi Elementary
School (oxidant concentration: 0.253ppni), the minute investigations
of the past medical history of the serious affected victims and their
family members showed that they were found to have considerably
strong allergic symptoms and hypersensibility, suggesting a
relationship between the serious photochemical smog symptoms and
hypersensitive constitutional disposition.
The test results showed no previously reported phenomena such
as the increase in indirect bilirubin.
-30 -
255
-------
Table 2-3-9 Past medical history and family history
Past medical history of the
victim
Family history
Urticaria, eczema, drug allergy, Father: Urticaria by eating
O.T cuttlefish and ham.
food allergy, allergic rhinitis
Mother: Rash caused by astringent
juice of Japanese chestnut, taro,
and Yam and cold drugs.
Brother: Rash caused by drugs
Y.H Urticaria causeded by cheese, Mother: Urticaria caused by
milk allergy, exanthema caused cider (?)
by cold rugs
T.K Used to wheeze when catching
a cold in childhood
K.O A rash appeared throughout
the face when yam juice came
into contact with the nose.
Used to wheeze when catching
a cold in the childhood.
Father: Suffering occassionally
from urticaria since a
few years before
Y.A
A rash came out when eating
half-broiled rainbow trout
when one year old and three
years old. A rash appeared
all over the body when a
cold drug was taken 2 months
before.
Sister: Suffers frequently
from urticaria
-31 -
256
-------
2-3-6 Correspondence between environmental conditions and reported
cases of photochemical smog victims
No sufficient analysis has been made with regard'to the
correspondence between environmental conditions and the number of
reported cases of photochemical smog victims. However, the surveys
made this year have clarified some noteworthy points as described
below.
a) • Three levels of oxidant concentration and the number
of reported victims
Fig. 2-3-2 shows the correspondence between the oxidant
concentrations in the air and the percentage proportions of photo-
chemical smog victims, according to the results of survey conducted
on 7,440 students of 10 schools in -Saitama Prefecture. As seen
from this figure, only one out of 2,000 students complained of
photochemical smog symptoms on a day when the maximum, oxidant level
was below 0.15ppm but on a day when the oxidant level exceeded
O.lSppm one out of 200 students complained of their physical
disorders, that is, the reported victims increased tenfold. One
out of five to six students were affected on a day when the oxidant
level exceeded 0.25ppm. The results of this particular survey
have revealed that the number of complaints of photochemical smog
symptoms sharply increases when the oxidant level exceeds 0.25ppm.
A similar survey was conducted in Kanagawa Prefecture and it produced
similar results, although no difinite percentage proportions-of the
reported cases were known because no specific shools had been.designated
for the survey.
- 32 -
257"
-------
Fig. 2-3-2 Oxidant concentrations and percentage proportions of
complainants of photochemical smog symptoms
i 20
o
•p
» 15 i
o
JB
o
o
2 10
o
to
ed
r-l
0.052^
<0.15
ppm
0.15 0.25
ppm< ppm <
July 15
Aug. 13
0.25
ppm <
July 15
Ox level
-33 -
258
-------
b) The times when the victims first complained of photo-
chemical smog symptoms and the oxidant concentration
in the air
In the case study on the days when many reported victims
occurred, it is seen that there are cases in which the peaks of
the numbers of reported Victims agree with the peaks of oxidant
levels in the air and also many cases in which considerable numbers
of reports had already begun to be made when the ozidant level
began to rise sharply. The oxidant alerts and alarms are issued
when the oxidant concentration has exceeded 0.15ppm and it is report^
ed to the schools after a certain delay and therefore it is obvious
that the initial reports of victims were not biased by the alerts.
Such reports indicate the presence of the people who are constitu-
tionally susceptible to photochemical smog hazards and these who are
particularly sensitive to such air pollutions and they are worthy
of further attention and investigations in relation to varions factors
such as physical exercises and the concentrations of other pollutants
in the air.
c) Other air pollutions, temperature and humidity
As for the concentrations of other pollutants and the
air temperature and humidity, the present survey has not produced
such results as to enable use to draw a definite conclusion. The
reports received from the prefectures contained some information
suffestively pointing out the fact that there occurred many
reported victims of photochemical smog victims on the days when
- 34 -
259
-------
the dust level was high during the morning or the discomfort index
was high but no accurate analysis was made, leaving this problem
to be solved in the future.
d) Differences according to the conditions of location
There were many cases in which one of the two closely located
schools produced many reported cases of photochemical smog victims
but the other school had not victims even when the students of both
schools were out of school buildings on the same day, suggesting
the presence of the factors related to the microclimatic conditions
in urban areas such as sunk places, elevated places, inlets and
flat places, airy or airless places. These are the problem
remaining to be solved in the future. There is an increased
necessity for the on-the-spot investigations at the schools where
many victims of photochemical smog occur. It is also essential
to carry out surveys and checks on the sources of primary pollution
in the neighborhoods of the schools. This type of survey was
conducted to some extent in Saitama Prefecture to find that there
is no source of such pollution near any schools. However, there is
such a case as the Daian Junior High School, in which the existence
of such pollution sources cannot be denied. It may be necessary
to make a check as to the sources of air pollution located near
the schools.
e) Social and psychological factors
It must be recognized as an inevitable phenomenon that a
collective psychological bias is given to the number of complaints
-35 -
260
-------
of photochemical smog damage. However, we would like to point out
that it would be mistaken if the variations in the number of complaints
are explained by this factor alone. This is condirmed by the fact
that complaints were reported before the photochemical smog alarms
were issued and also from the results of the careful observations
made by the surveyors, i However, it can be said that the social,
historical and psychological biases are inevitably given to the
complaints- as far as the complaints are made voluntarily on the
basis of the subjective symptoms of "the victims.
¥e would like to add that the development of subjective index
of the effects of photochemical smog on human health, the physiological
and biochemical indexes or parameters is. one of the important subjects
of study to be made in'the future.
4. " Conclusion
Owing to the cooperation of the prefectural authorities
concerned, many advances were made in this year's survey on photo-
chemical air pollution hazards to human health as summarized below.
In a word the numbers of reported victims of photochemical
smog in 1975 tended to be larger in the eastern part than in the
western part of Japan and the survey results showed clearly there
was a parallel relationship between the numbers of reported victims
and oxidant concentrations in the air and that the percentage
proportions of reported victims varied according to the oxidant
levels.
-36-
'261
-------
This year's survey has found some cases in Saitama and
Kanagawa Prefecture where the reported victims began to occur
before the "alert » were issued when the oxidant level rose sharply.
In this respect there are various noteworthy questions to be solved
in the future such as the relationship of photochemical smog and
other pollutants and th,e exposure differences (outdoor excercises
and the like) and sensitivity differences due to constitutional
disposition of the individual.
As for the photochemical smog symptoms, the surveys
conducted in the various prefectures showed that the mucous membrane
irritation and also general symptoms showed fairly large percentages.
In some places there occurred serious cases where the victims were
taken to hospital. A further study must be made on such serious
cases of photochemical smog symptoms. This year's survey has
revealed the fact the cases where £he victims had to rest in
the rest-room'and the cases where the victims complained of the
symptoms remaining on the following day accounted for 0.2^ to 3%
and 1% to &P, respectively. These cases may be considered as
transitional to the serious cases and require further analysis and
survey in the future.
No differences were observed between male and female
students with regard to the number of complaints in all prefectures
•
concerned.
As for the 'differences according to whether the students
were taking excercises out of doors or staying indoors, it was
-37 -
262
-------
noteworthy that there was observed an obvious relationship between
the reported complaints and outdoor exercises at the Mihashi
Junior High School in Saitama Prefecture. Generally speaking,
however, it has been found that there occurred.fairly large numbers
of reported victims whether the students were taking exercises out
of doors or remaining in the classrooms, suggesting that when the
photochemical air pollution has exceeded a certain level there
occur the victims when exposed to the pollutants wherever they are.
The effects of the health condition and predisposition of
the individual students on the damage by photochemical smog had been
suspect. In this respect, this year's survey can be said to have
successfully play its role as a pilot study, although it is still
premature to draw any definite conclusion. Further developments
in this area of study are desired.
This yearfs survey has revealed the fact that the reported
victims began to occur before the "alert" and "alarm" were issued
in the respective areas. This fact indicates the urgent need for
further improvements of the system of warning issuance and delivery
and for the observations on the spot and a study on the relation-
ship of the warnings and the occurrence of victims so that thus
obtained information may be effectively used in the health care at
school.
Reviewing the results of the present survey, we felt
keenly that it would be impossible to prevent the photochemical
air pollution .hazards unless further advances are made in the control
- 33 -
263
-------
of pollutants at the soirees of pollution. Adding a few more
words, the reported v^etumsv in this report are those who voluntarily
complained of their subjective symptoms.
- 39 -
264
-------
Photochemical Oxidants Control Measures in Japan
(Environment Agency 1
Japanese Delegation
1. Introduction
la Japan, since the summer of 1970, there have occurred
each summer the cases of health damage with such typical symptoms
as eye irritation, throat sore and cheat oppressed feeling, which
are considered attributable to photochemical smog. Apart from
the above light cases, relatively serious cases such as general
symptoms and nervous disorders also have been reported. It is
generally considered, although there are some different opinions
in regard to such relatively serious cases, that these are caused
by the effects of the pollutants which are secondarily produced
as a results of photochemical reaction of nitrogen oxides and
hydrocarbons. It is now urgently needed that a clear explanation
and solution of this problem was obtained for the sake of the
preservation of ambient air quality.
2. Basic conception for abating photochemical oxidants
Photochemical oxidants were adopted as an index for photo-
chemical air pollution and there was established the ambient air
quality standard for photochemical oxidants from a viewpoint of the
protection of human health in May 1973 •
On the basis of the Central Council for Control of Environmental
Pollution's proposal that the hourly value of photochemical oxidants
should preferably be held down to less than 0.06 ppm for the protection
-------
of human health paying attention to the protection of the effects
of a.short—term exposure to photochemical oxidants the Government
officially announced that the same value for photochemical oxidant
concentrations in the air as the environmental standard for ambient
air pollution as'given in Article 9 of the Basic Law for Environ-
mental Pollution prevention. And this value was required to be
achieved at the earliest possible time.
At the same time when above standard was determined the
ambient air quality standard for nitrogen dioxides was established,
paying attention to its .own effects on human health.
In Japan various measures have been taken to achieve the
requirements of the ambient air quality standard for photochemical
oxidants. As for nitrogen dioxides, one of the precursors of photo-
chemical oxidants, the ambient air quality standard for nitrogen
dioxides has been established and HOx prevention measures have been
taken. In addition to that, measures are also taken for decreasing
hydrocarbons, another precursor of photochemical oxidants.
The quantitative relationship between the concentration of
hydrocarbons and the production of photochemical oxidants was
searched for and a comprehensive study was made by the Central
Council for Control of Environmental Pollution and it proposed in
August 1976 a guideline for the hydrocarbon concentrations in the
air (hourly values of 0.20 to O.J1 ppm during 6 to 9 in the morning)
so that adequate measures would be taken in the fugure.
As we have just seen, the Japanese .are endeavoring to prevent
266
-------
the production of photochemical oxidants by reducing both nitrogen
dioxides and hydrocarbons, thereby to decrease the total quantity
of photochemical reaction.
3» Control strategy and various measures
In order to promote the systematic and efficient execution of
the photochemical air pollution control measures, the Japanese
Government in June 1972 established the "Photochemical Smog Control
Promotion Conference11 composed of the bureau chiefs of the admini-
strative organs concerned and in April 1975 the Conference decided
on the basic policy to be taken for the promotion of the photochemical
smog control measured to be taken in the future. That is to say,
the Conference decided that increased efforts should be made to
reduce the concentrations of nitrogen oxides and hydrocarbons in
the air in an attempt to prevent photochemical air pollution and
that further research and investigations should be made to have a
better knowledge of the mechanism of air pollution, and that increased
efforts should be made to improve further the photochemical smog
warning and monitoring systems, health protecting measures and
international cooperation in this field.
We will make our atmost to carry on our anti-pollution measures
in accordance with the above basic policy. The following are the
measures which are being taken now and the future trends.
267
-------
(l) Precursors control measures
a- Hydrocarbons
As for the mobile sources of hydrocarbons, the emission
standards enforceable in and after IT1970 require passenger-
cars to reduce the average quantity of exhaust gases by 9?$
from when no such standards were enforced. From now one,
regulations will be enforced to control the emission of hydro-
carbons from stationary sources such as oil tanks (now control
measures are already taken in the form of administrative guid-
ances for some industrial installations) and also from trucks
and diesel motor vehicles. Is for organic solvents, we are
planning to enforce proper emission standards on the basis of
the results of technological assessment. (See Fig = l)
b. Nitrogen oxides
For this, reference should be made to "Hitrogen Oxides
Control Measures in Japan".
(2) Emergency Measures
In addition to the precursors control measures which are
taken at normal times, emergency measures are taken when photo-
chemical oxidant levels are higher than normal and likely to
continue in view of the existing weather conditions.
In such a state of emergency the 23 prefectural govern-
ments issue warnings as given in Table 1 to ask or order
precursors emitting industrial installations to curtail the
268
-------
Pig. 1 Plow Chart of Hydrocarbons Control Measures in Japan
Central Council
for Control of
Environmental
Pollution
1976. 4
1977. 4
1978. 4
The Central Council established
guide values for the control of
hydrocarbon concentrates in the
air
(August 13)
Sationary
sources
Organic solvents
etc.
Grasping of the develop-
ments of HC-preventive
facilities and low-solvent
products
Formulation of
control policy
(Guideline)
101
CJV
10
Survey on emission
of hydrocarbons
from different
sources
(FY1973)
Survey on the con-
centrations of hydro- _
carbons emitted from
different sources
Study on the
control methods
to be employed
Administrative
guidances
Full enforce-
ment of control
standards
Achievement
of the
guide valueti
requirement^
/Scopes of control (regions, seasons) \
/ Installations to be subjected to control j
I Methods of control I
I Emission standards for concentrations /
Mobile
sources
Emission standards
for passenger-cars
(Emission standards enforceable
in and after FY1973,
Emission standards enforceable
in and after FY1975, etc.
Study on the enforcement
of control standards for
diesel vehicles and
trucks
Tightening of
control of diesel
vehicles and
trucks
-------
Table 1 Photochemical smog warning issuance standards and percentage
reductions of fuels consumption
Item
Pre-
fecture
Hiyagi
Fukuahima
Tbaraki
Tochigi
Gunma
Saitama
Chiba
Tokyo
Kanagawa
Shizuoka
Aichi
Me
Shiga
Kyoto
Osaka
Hyogo
Nara
Kakayama
Okayama
Hiroshima
Yamaguchi
Tokushima
Ehime
Forecast
Warning issuance standard
(Concentration ppm)
When predictable from
weather conditions
- -
When predictable from
weather conditions
ti
M
It
II
II
It
-
0.1
0.1
-
-
0.1
0.1
0.1
0.1
When predictable from
weather conditions
0.1 (information)
0.12 (Special information)
0.1 (information)
0.15 (Special information)
-
When predictable from
weather conditions
Percentage
reduction *
w
Preparatory
measures
-
Preparatory
measures
n
Voluntary
cooperation
n
20
Voluntary
cooperation
n
-
Voluntary
cooperation
Preparatory
measures
-
—
Preparatory
measures
20
—
-
30
20
20
—
Voluntary
cooperation
Alert
Warning issuance
standard (Concen-
tration ppm)
0.15
0.15
0.15
0.15
0.15
0.15
0.15
0.15
0.15
0.15
0.15
0.15
0.15
0.15
0.15
0.15
0.15
0.15
Weather condi-
tions etc
0.15
0.15
0.15
0.15
(Note) *: The "percentage reduction" ^is the
•that at pnTtnftl •fHmfla
-------
(As of Apr., 1975)
Percentage
reduction
w
20
20
20
20
20
20
20
20
20
20
20
20
_
20
20
20
-
20
40
20
20
20
40
Alarm
Warning issuance
standard (Concen-
tration ppm)
0.3
-
0.3
. 0.3
0.25
0,25
0.3
0.3
0.3
0.3
0.3
0.3
0.3
0.3
0.3
0.3
0.3
0.3
Weather condi-
tions etc.
-
-
0.3
0.3
Percentage
reduction
w
40
_
40
40
40
40
40
40
25
40
30
30
-
40
40
20
-
40
40
-
-
30
40
Emergency
Warning issuance
standard (Concen-
tration ppm)
0.5
0.5
0.5
0.5
0.5
0.5
0.5
0.5
0.5
0.5
0.5
0.5
0.5
0.5
0.5
0.5
0.5
0.5
Weather condi-
tions etc.
0.5
0.5
0.5
0.5
* _ 1 J_l TS>
alarm
Percentage
reduction
w
40
40
40
40
40
40
40
40
40
40
40
40
-
40
40
40
-
40
40
40
40
40
40
271
-------
amounts of fuels they use and also call on the general public
to use their motor vehicles less frequently 'and to refrain
from taking vigorous physical exercises.
(?) Health -protection measures
For the purpose of health protection, measures such as
disseminating the knowledge of photochemical smog widely among
the general public and giving guidances in the emergency actions
to be taken when photochemical warnings are issued.
(4) Promotion of surveys and researches
The surveys and researches concerning photochemical air
pollution have been promoted, paying special attention to the
following points.
a. To clarify the mechanism of photochemical reaction.
(Experiments in smog chambers)
b. To clarify the effects of photochemical air pollution on
human health and vegetation
c. To clarify the weather conditions contributing to photo-
chemical reaction and to develop a reliable prediction
model.
The subjects of those surveys and researches and their
relations to the countermeasures are shown in Fig. 2.
272
-------
Pig. 2 Photochemical air pollution survey and research system
00
to
to
Health damage survey
. Establishment of quantities
and relationships in relationv
to mucous membrane irrit&tion
. *Survey on abnormal cases
Health
damage
Damage to
vegetation
Regional application of
prediction model
. Systematization for regional
application of prediction model
. Checking of forecasting accuracy
by use of prediction model
J
Ambient ai
pollution
Mr pollution
monitoring
-S\
Weather
conditions
\
^/
Meteorological
observation in
the brictional
layer
Experiments in smog chamber
. Hydrocarbon
analysis in relation to the
formation of PAN, aldehyde, etc
Grasp of quantitative
relationships of Ox-Hc-NOx
n
; Generated
substances
Survey on emission factor
. Improvement of NOx factor
accuracy except for boilers **
. Collection of data concerning
factor of soot and dust
Reaction
conditions
Investigations on trace
substances
. Measurements of concentrate
of trace substances such as
PAN, aldehyde, acrolein,
cyanogen, sulfates, nitrate:
in the ambient air
. Data concerning the quantity
-reaction relationship for
health damage
NOx and He emission
regulation
* Since not much is still unknown about such relatively serious cases as general symptoms and nervous disorders,
investigations are now under way about their relationships to photochemical air pollution.
** Emission factor have been grasped with a considerably high accuracy for boilers.
-------
4- Monitoring system and photochemical air pollution in
recent years
(l) Since 1968 when photochemical oxidant monitoring stations
were first set up in Japan, the number of them have yearly
increased and there were 519 stations located in 282 cities
throughout the country in FH974.
Table 2 Increases of oxidant monitoring stations and the
number of the days when alerts were issued *
1968 '69 '70 »71 '72 '75 '74 '75
Number of cities
Kumber of
monitoring
stations
Number of days
alerts were
issued
2 2 4 38 110 209 282
2 2 10 68 175 349 519
7 98 176 328 288 266
* A total number of days when prefecture! governments issued
photochemical smog alerts*
As for the measurement method of the photochemical oxidant
levels in the air, colorimetry or coulometry using neutral
buffer potassium iodine solution is used. These methods are
used because oxidants which are measurable by those methods,
are a suitable index for photochemical air pollution, the
monitoring stations using these methods are easy to operate and
9 274
-------
maintain and suited for the monitoring on a nationwide "basis.
Apart from these monitoring system, the Environmental
X
Agency undertake observations of low-layer ambient air to
provide useful information to local autonomous bodies so that
they can take effective emergency measures when needed.
In order to carry out the analysis of weather conditions
tending to cause photochemical air pollution and to strengthen
the forecasting system, the atmospheric pollution meteorological
centers are established at six local meterological observatories.
(2) Photochemical air pollution in recent years
Table 3 shows the numbers of days when oxidant concentra-
tion in the air exceeded 0.15 ppm at which oxidant alerts are
to be issued. The measurements of oxidants were made at the
monitoring stations where oxidants have been measured conti-
nuously since 1970. There were several days when the oxidant
level exceeded 0.3 ppm in a year but there was no day when it
exceeded 0.5 ppnt.
Table 4 shows the numbers of days when alerts or forecasts
were issued in Tokyo. As seen from this table, the ratio of
days when alerts or forecasts were issued to the days when
photochemical-causing weather conditions occurred has been
decreasing since 1973•
10 275
-------
Table 3 Numbers of days when the hourly value for oxidants
exceeded 0.15 ppm in 1970 to 1974 years
s
City Honitoring station 1970 1971 1972 1973 1974
Tokyo In" front of Tokyo 04 7 25 2
Metropolitan Govern-
ment Office
11 State-operated Tokyo" 28 15 7 28 4
Photochemical Oxidants
Honitoring Station
11 Setagaya 1 20 10 22 9.
Osaka State-operated Osaka
Photochemical Oxidants 0975
Monitoring Station
Sakai Hamadera 1 4 16 14
Takarazuka Old People Welfare 1 11 14 5
Center
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Table 4 Comparison of oxidant forecast and alert issuances and
the days when there occurred weather conditions for
causing photochemical smog, in Tokyo *
N. . Item
Number of days Number od days ' Number of days
Ox alerts were 0^ forecast or when there were
issued alert were issued photochemical smog-
causing weather con-
Month, x ditions occurred
Tear \
June
July
1973
yiy Aug.
Total
June
July
1974
Aug.
Total
June
July
1975 Aug.
Total
June
July
1976
Aug.
Total
A
4
16
13
33
6
2
9
17
7
6
11
24
1
3
(A / C *)
(50*)
(80 ")
(72 »)
(72 ")
(46*)
(50 ")
(69 ")
(57 ")
(64 *) -
(43 ")
(52 »)
(52 ")
(17*)
(25 ")
B
7
18
15
40
6
3
12
21
9
9
11
29
2
4
(B /C*)
(88*)
(90 ")
(83 ")
(87 ")
(46*)
(75 !')
(92 ")
(70 »)
(82*)
(64 ")
(52 ")
(63 ")
(33*)
(33 ")
C
8
20
18
46
13
4
13
30
11
14
21
46
6
12
* Weather conditions
Atmospheric- temperature:
Wind velocity:
Solar radiation:
Over 20°C (daytime)
Less than 5ia/sec
(9:00, 12:00 and 15:00 average)
40 cal/cm2/h over 3 hours
(9:00 to 15:00)
(Tokyo District Meteorological Observatory statistics)
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