Introduction
Particle pollution is a mixture of microscopic solids and liquid droplets suspended
in air. This pollution, also known as particulate matter, is made up of a number ofcomponents, including acids (such as nitrates and sulfates), organic chemicals,
metals, soil or dust particles, and allergens (such as fragments of pollen or moldspores).
Fine

particlepollutionor

PM 2.5 㻌 describes

particulatematterthat is2.5

micrometers in diameter and smaller - 1/30th the diameter of a human hair.
Fine particle pollution can be emitted directly or formed secondarily in theatmosphere. Examples Sulfates are a type of secondary particle formed from sulfur
dioxide emissions from power plants and industrial facilities. Nitrates, another atype of fine particle, are formed from emissions of nitrogen oxides from power
plants, automobiles, and other combustion sources.
The chemical composition of particles depends on location, time of year, andweather.
Health studies have shown a significant association between exposure to fineparticles and premature death from heart or lung disease. Fine particles canaggravate heart and lung diseases and have been linked to effects such as:
cardiovascularsymptoms;

cardiacarrhythmias;heart

attacks;

respiratory

symptoms; asthma attacks; and bronchitis. These effects can result in increased
hospital admissions, emergency room visits, absences from school or work, andrestricted activity days. Individuals that may be particularly sensitive to fineparticle exposure include people with heart or lung disease, older adults, andchildren. (referred from the website of US-EPA)
The Ministry of the Environment, Japan (MOEJ) has been taking actions against
PM 2.5 , including establishment of environmental quality standard, assessment of
automated measuring equipment having equivalence to the standard measuringmethod, promotion of conduct of monitoring in cooperation with local governments,and studies on the guidelines for raising an alert. In the future, the EANET
participant countries are also to discuss reinforcement of monitoring of PM 2.5 , sosummarizing and communicating the approaches and experience in Japan will
have significant meaning for the EANET participant countries.
Aiming at possible practical application in the future training for EANET
participant countries, and other opportunities, the approaches adopted so far inJapan for PM 2.5 are summarized.

Contents
1

Background to establishing the Environmental Quality Standards (EQSs)㺃㺃㺃㺃1

2

Assessment methods and assessment results of equivalence between theautomated PM 2.5 measuring equipment and the standard measuring method(filter sample collection method) 㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃4

2.1 Measuring method of PM 2.5 㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃4
2.2 Conditions that the filter sample collection method needs to satisfy㺃㺃㺃㺃㺃㺃㺃㺃4
2.3 Conditions that automated measuring equipment needs to satisfy㺃㺃㺃㺃㺃㺃㺃㺃㺃6
2.4 Equivalence assessment of an automated measuring equipment㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃7
3

The processing standards for administrative affairs for continuous monitoringof air pollution based on the Air Pollution Control Law㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃10

4

Distribution of PM 2.5 monitoring stations in Japan㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃25

4.1 Changes in the number of PM 2.5 monitoring stations㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃25
4.2 Changes in the number of sites conducting the component analysis of PM 2.5
㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃26
5

Types and the actual number of pieces of automated measuring equipment in
operation in Japan㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃28

6

Methods for releasing monitoring data㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃29

6.1 Ministry of the Environment, Japan (MOEJ) 㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃32
6.1.1 Release through written reports㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃32
6.1.2 Release through website㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃32
6.2 Niigata Prefecture㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃41
6.2.1 Release through written reports㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃41
6.2.2 Release through website㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃41
6.3 Niigata City㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃44
6.3.1 Release through written reports㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃44
6.3.2 Release through website㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃44
7

Provisional Guideline for Raising Alerts 㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃49

7.1 Positioning of the guideline㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃49
7.2 Methods for determining the raising of an alert㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃50
7.3 Provisional guideline for raising alerts㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃52
7.4 Enforcement methods㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃㺃53

1 Background to establishing the Environmental Quality Standards (EQSs) 1)
The United States had established air quality standards for fine particulate matter(PM 2.5 ) in 1997, and these standards were revised in September 2006. The World
Health Organization (WHO) also released the 2005 edition of guidelines on target
values for the Environmental Quality Standards (EQSs) in October 2006, which
laid out air quality guidelines and provisional target values for PM 2.5 . In theEuropean Union, an EU directive concerning the upper limit for the concentrationof PM 2.5 was announced in June 2008.
In light of these movements around the world, the Ministry of the Environment,
Japan (MOEJ) began to conduct a study on the impact of exposure to fineparticular matter in 1999 with the objective of elucidating the relationshipbetween exposure to PM 2.5 in the general air environment and its impact on health.
The results of this study were summarized and published in July 2007. Based on
findings gathered in Japan and abroad, a study committee to assess the healthimpact of fine particulate matter was set up in May 2007 with the objective ofconducting a professional review on assessments on the health impact of fineparticular matter on respiratory and circulatory systems. The results of the study
weresummarizedinareport

in

April

2008.

According

to

this

report,epidemiological and toxicity findings supported the hypothesis that PM2.5 on thewhole has a certain level of impact on human health, and the report asserted theneed to conduct a careful review on the methods of quantitative risk assessment inorder to establish target values for EQSs.
Consequently, in June 2008, MOEJ established a special committee on the risk
assessment methods for fine particulate matter under the Air Environment
Subcommittee of the Central Environmental Council, with the aim of deliberating
on quantitative risk assessment methods for PM 2.5 . The committee summarized
and published its findings in a report in November the same year.
In December 2008, MOEJ consulted the Central Environmental Council about theestablishment of EQSs for PM 2.5 , prompting the establishment of a special
committee for EQSs for fine particulate matter under the Air Environment
Subcommittee of the Central Environmental Council. This special committeestudied guideline values for the establishment of EQSs, taking into consideration
the characteristics of PM 2.5 and its behavior in the human body, ambientconcentration in air, qualitative and quantitative assessment on health impact,andconducted

investigations

anddeliberations

into

assessments

on

the

achievement status for EQSs. In August 2009, it made a comprehensive decision－ 1 －based on scientific findings from Japan and abroad, and came up with guideline
values for the establishment of EQSs for PM 2.5 that give consideration to providing
adequate protection to the health of population groups in the regions.
Based on this, the Central Environmental Council reported on the establishment of
EQSs for PM 2.5 , and the EQSs were announced and enforced in September 2009.
(Table 1)
EQSs are established as standards that should ideally be maintained for theprotection of human health, in line with the Basic Environment Act. The
environmental quality standard for PM 2.5 is as follows.
࣭The environmental quality standard for fine particulate matter (PM 2.5 ) is
stipulated as an annual average that is less than or equal to 15.0Ǎg/m 3 ,and a 24-hour average that is less than or equal to 35Ǎg/m 3 .
࣭In places that have proven ability to appropriately identify a state of air
pollution caused by fine particulate matter, measurement is taken usingmass measurement with filter sample collection, or through an automatedmeasuring equipment that has proven ability to obtain an equivalent value
as the mass concentration measured using the measurement method
described above.
࣭Fine particulate matter is defined as airborne particles that pass through asize-selective inlet with a 50% efficiency cut-off at 2.5Ǎm aerodynamic
diameter.

－ 2 －Table 1

Background to the establishmentof the Environmental Quality Standards (EQSs)
Year/month

Event

July 1997

Establishment of National Ambient Air Quality Standard (NAAQS) for
PM 2.5 by US-EPA

1999-2006

Studies on the impact of exposure to fine particulate matter

September 2006

Revision of NAAQS by US-EPA

October 2006

Establishment of WHO Air Quality Guidelines

May 2007

Additional resolution to the “Amendment Act on Reduction of Total
Amount of Nitrogen Dioxide and Particulate Matters Originating from
Automobiles in Designated Areas” (Strengthening of measures)

July 2007

Release of outcomes of studies on exposure impact of fine particulatematterMay 2007 – April

Study committee to assess the health impact of fine particulate matter

2008
June 2008

Public announcement of EU EQSs

June 2008 –Special committee on the risk assessment methods for fine particle

November 2008

matterDecember 2008

Inquiry about establishment of the EQSs of fine particulate matterFebruary 2008 –Special committee for the EQSs for fine particulate matter

August 2009
September 2009

Announcement of the Environmental Quality Standards

－ 3 －

2

Assessment methods and assessment results of equivalence between theautomated PM 2.5 measuring equipment and the standard measuring method (filter
sample collection method)
2.1

Measuring method of PM 2.5

The announcement stipulates that the measuring method of PM 2.5 is “a massconcentration measuring method by filter sample collection or a method using
automated measuring equipment recognized to produce values equivalent to themass concentration values gained through the former method.” This measuringmethod was discussed by the Particulate Matter 2.5 (PM 2.5 ) Measuring Method
Advisory

Committee

of

the

Air

Environmental

SectionintheCentralEnvironment Council, and the discussion process is described in the report ofsaid Committee. After the discussion, the filter sample collection method, which
has been in use in the US and Europe, was adopted as the standard measuringmethod in Japan. However, the problem with the filter sample collection method
is the manpower required to prepare, install, collect, and weigh filters, and alsothat measured values thus gained are merely 24-hour averages and are notgained in real time. For this reason, for observations conducted to assess theenvironmental quality standard, it is recognized that measurement using
automated measuring equipment is more useful 2) ࠋMeanwhile, as the announcement states, an automated measuring equipment isrequired to produce values equivalent to those gained from the filter sample
collection method, so the Ministry of the Environment, Japan (MOEJ) conductedequivalence assessment tests on automated measuring equipment entered bydomestic and overseas manufacturers that had made an application. The result
was released in October 2010 and in October 2011, and throughout Japan MOEJ
has been conducting monitoring using the automated measuring equipment
recognized to produce values equivalent to those gained from the standard
measuring method.
This chapter will discuss the filter sample collection method for measuring PM 2.5
and conditions required for automated measuring equipment and its features, aswell as the equivalence assessment method using the automated measuring
equipment.
2.2

Conditions that the filter sample collection method needs to satisfy

As stated above, it has been stipulated that the filter sample collection method is－ 4 －the standard measuring method of PM 2.5 in Japan. The method is to collectambient fine particles in the air by suction filtration, and to weigh and determine
the mass by means of a balance. The reason why this method was adopted inJapan as the standard method for measuring PM 2.5 is that physical quantity ofmass concentration can be directly measured and that detailed provisions will
make it possible to guarantee the precision and reproducibility of measurements.
Conditions that the filter sample collection method should satisfy will be
described below.
(1) Features of the particle size classifier
According to JIS Z 8851, the 50% sizing diameter should fall between
2.5r0.2 Pm and the ratio of the 20% sizing diameter against the 80% sizing
diameter should be 1.5 or smaller.
(2) Differences in temperature from the open air
The allowable differences in temperature between the filter-holding section
and the open air should fall between r5qC. This condition must always be
kept until the collected samples have been gathered, in order to reduce theeffect of the vaporization and adhesion of semi volatile substances evenafter the collection of samples.
(3) Material for the filter
PTFE (Polytetrafluoroethylene) must be used for the filter. Some of thecommercially available products come with easily operable support rings.
(4) Suction flow rate
The actual flow should be controlled and displayed.
(5) Constant weight conditions and the sensitivity of a balance
For achieving constant weight of filters, the temperature should be within
21.5r1.5qC, the relative humidity should be within 35r5%, and theconditioning time should be 24 hours or over. A balance with a reciprocal
sensitivity of 1 Pg or less should be used for weighing. The conventional
conditioning conditions of suspended particulate matter (SPM: Particles
left after particles with aerodynamic diameter larger than 10 Pm have been
completely separated) used to be that the temperature should be 20qC, andthe relative humidity 50%. However, for PM 2.5 , the relative humidity forconditioning is lower, in order to eliminate as much of the effect as possibleof the humidity.

－ 5 －(6) Concentration measuring range
2 Pg/m 3 should be the lowest limit and a precision of at least 200 Pg/m 3
should be secured for the higher concentration range.
2.3

Conditions that automated measuring equipment needs to satisfy

The Special Committee report describes the conditions that automatedmeasuring equipment needs to satisfy, as follows.
(1) Relation between physical quantity and mass and between the standard
measuring methods
It is necessary that the physical quantity to be measured and the mass havea definite relation, or that the correction relation between the physicalquantity to be measured and the mass is clear. The measurement principle
includes the Tapered Element Oscillating Microbalance (TEOM), thebeta-ray absorption method, the light-scattering method, and a combinationof other measurement principles. However, other types of principles are not
to be excluded.
(2) Features of a particle size classifier
A particle size classifier shares the same features as the standard
measuring method. Also, methods such as some of the light-scattering
methods not using a particle size classifier need to deliver the same level of
performance as the above-described particle size classifier.
(3) Averaging time (Temporal resolution)
The averaging time for automated measuring equipment should be 24 hours.
At the moment, equivalence for an hourly value cannot be confirmed andthe value should be treated as a reference value.
(4) Concentration measuring range
For the concentration measuring range, 2 – 200 Pg/m 3 should bemeasurable as a 24-hour average.
(5) Inspection and calibration methods
Technical methods for inspection and calibration based on each measuring
principle should have been established and the constancy of the measured
value should be maintained through regular inspections.
(6) Equipment Differences－ 6 －The differences in 24-hour averages should fall within a certain range when
multiple pieces of automated measuring equipment of the same model areused simultaneously for measurement (parallel measurement).
(7) Suction flow rate
The actual flow should be controlled and displayed.
(8) Response to changes in the relative humidity
Automated measuring equipment should desirably have functions forsuppressing changes in mass concentration caused by relative humidity, by
equipping a dehumidifying system, etc.
Multiple pieces of automated measuring equipment based on the various
measurement principles shown in (1) are commercially available and manyof the manufacturers have adopted the beta-ray absorption method.
2.4

Equivalence assessment of an automated measuring equipment

It is stipulated in the announcement of the environmental quality standard that
automated measuring equipment recognized to have equivalence to the standard
measuring method should be used. The outline of the equivalence assessment
test is described below.
It is advisable to conduct an equivalence assessment test for as broad a range as
possible,covering

both

the

low

and

high

concentration

ranges.

Also,measurement of PM 2.5 is affected by the following phenomena: sulfate
deliquesces if the relative humidity is 80% or higher, and nitrates evaporate athigh temperatures. In consideration of these phenomena, it has been decided
that periods and places shall be chosen which characterize factors affecting themeasurements of PM 2.5 . For this reason, it has been decided that the tests shallbe conducted in summer and winter in urban and rural areas.
The equivalence assessment of automated measuring equipment and thestandard measuring method should follow the assessment method based on thequality control techniques. The equivalence assessment is done by counting thenumber of the values outside the control limits drawn on both sides of the y=x
diagonal in consideration of errors between the values gained from the standard
measuring method and those from the automated measuring equipment among
the values gained from the standard measuring method plotted on the x-axis andthose gained from the automated measuring equipment plotted on the y-axis.

－ 7 －(Figure 1) The maximum tolerable number of the values outside the control
limits is calculated based on single sampling inspection plans having desired

measuring equipment (Pg/m 3 )Values measured by automatedoperating characteristics by variables.

Values measured based on thestandard measuring method (Pg/m 3 )Figure 1 Image of equivalent test for automatic monitor㻌
Bold broken lines show control limit area. Open and closed
circles show data within and out of acceptable range, respectively.
As of November 2014, those listed in Table 2 below are automated measuring
equipment recognized to produce values equivalent to those gained from thestandard measuring method.

－ 8 －Table 2

List of equipment that equivalence with standard measurement
method is confirmed* (As of November 20, 2014)

Model name

Manufacturer

Release date of the result

PM-712

Kimoto Electric

October 15,2010

PM-717

Kimoto Electric

October 15, 2010

FPM-377

DKK-TOA CORPORATION

October 15, 2010

APDA-375A

HoribaOctober 15, 2010

FH62C14

Thermo Fisher Scientific

October 15, 2010

SHARP 5030

Thermo Fisher Scientific

October 15, 2010

MP101M

Environnement S.A

July 4, 2011

5014i

Thermo Fisher Scientific

July 4, 2011㸨The sources are “The Results of Equivalent Test in Winter 2009 and Summer2010 (October 15, 2010)”and “The Results of Equivalent Test in Summer 2010 and Winter2010 (July 4, 2011)” released by the Air Environment Division, Environmental
Management Bureau, MOEJ.

－ 9 －

3

The processing standards for administrative affairs for continuous monitoringof air pollution based on the Air Pollution Control Law
In March 2010 the Ministry of the Environment, Japan (MOEJ) revised “Theprocessing standards for administrative affairs for continuous monitoring of air
pollution based on the Air Pollution Control Law” (hereinafter referred to as“Paperwork Standards”), which demonstrate the implementation methods ofcontinuous monitoring of air quality, and the “Manual for Continuous
Monitoring of Air Pollution” in response to the established environmental
quality standard (EQSs) to state that continuous monitoring of PM 2.5 must be
conducted as a legally prescribed transaction entrusted to a local municipality
by individual prefectures and the cabinet-designated cities under the Air
Pollution Control Law. The Paperwork Standards include description about
accumulation of scientific knowledge about behaviors of PM 2.5 and its precursors
in the atmosphere to seek effective countermeasures and implementation ofcomponent analysis as well as mass concentration measurement to estimate thecontributing ratio of possible sources of PM 2.5 . The sections referring to thedescription about PM 2.5 are reproduced below, providing specific example cases.
Proceeding Standard on Air Quality Monitoring Work Based on Air Pollution
Control Law (Finally Revised on August 30, 2013) (Described only PM 2.5
Section)Ϫ Continuous Monitoring for PM 2.5 Mass Concentration
1.

Monitoring Items

Fine particulate matter (PM 2.5 ), its environmental quality standards (EQSs)
was established in September 2009, shoud be measured.
2.

The number and allocation of monitoring stations(1)

The number of monitoring stations
In accordance with the examples *1 referred to in II - 2. (1) of thePaperwork Standards.

*1

A facility, which incorporates the measurement devices for themonitoring objects listed in above 1 to continuously monitor the status ofair pollution, is referred to as a monitoring station. The prefectures shalldetermine the standard for preferable number of monitoring stations forthe monitoring items in the individual prefectures based on consultation
with the cabinet-designated cities. The standard for preferable numberof monitoring stations shall be determined by adding the required－ 10 －

number of monitoring stations from the nationwide perspective as
specified in (A) below and the required number of monitoring stations
from the regional perspective as specified in (B) below.
Note)

The standard for preferable number of monitoring stations must
be determined from the standpoint of protecting human healthfrom any air pollution and preserving the human living
environment. Therefore, it shall not include the number of thosemonitoring stations that are installed in areas or locations suchas on the roadways, which are not associated with any normal
human life and thus are not used for judgment on whether or
not the EQSs are successfully met. In addition, it indicates thenumber of monitoring stations to help identify the status of air
pollution in the entire area concerned and thus, it shall notinclude the number of those monitoring stations intended forthe specific purposes listed below.
• Identification of unexpected and highly concentrated pollution
caused by any specific sources(A)

Determination of the required number of monitoring stations from thenationwide perspective(i)

Determination based on population and habitable area
The EQSs, guideline values, and other indicators for air pollutants(hereinafter referred to as “EQSs, etc.”) have been established fromthe standpoint of protecting human health. Therefore, the number ofmonitoring stations determined for a prefecture on the basis of theindicator of human exposure to air pollutants, namely population or
habitable area standards (calculated by subtracting the areas offorests and lakes from the gross area) listed below, whichever issmaller, is defined as the baseline number of monitoring stations forthe prefecture.
(a)

One monitoring station per population of 75,000(b)

One monitoring station per habitable area of 25 km 2

In practice, the number of monitoring stations may be adjusted as
appropriate by regional division established by subdividing aprefecture into several regions according to the situation of pollution
sources, population distribution, weather conditions, and other－ 11 －

factors.
(ii) Adjustment of the number of monitoring stations according to thelevel of environmental concentration among the monitoring stations
installed in all prefectures, there is identified the monitoring
station that has recorded the highest value for a given monitoring
item on the basis of the applicable EQSs or other performance index
in the past three years or so, and the highest value is labeled asshown below. Then, the number of monitoring stations for eachmonitoring item shall be selected as follows: The number ofmonitoring stations determined in (i) is selected for the prefectures
having the monitoring stations falling under “High,” the number ofmonitoring stations corresponding to about one-half of that
determined in (i) is selected for the prefectures having themonitoring stations falling under “Medium,” and the number ofmonitoring stations corresponding to about one-third of that
determined in (i) is selected for the prefectures having themonitoring stations falling under “Low.”“High”:

Does not meet the EQSs, etc., otherwise successfully
meets the EQSs, etc. but exceeds 70% of the standard
value.

“Medium”: Successfully meets the EQSs, etc., although ranges from
30% to 70% of the standard value.
“Low”:

Successfully meets the EQSs, etc. and does not exceed
30% of the standard value.
In practice, the number of monitoring stations may be
adjusted as appropriate to correspond to theenvironmental concentration levels by regional division
established by subdividing a prefecture into several
regions according to the situation of pollution sources,
population distribution, weather conditions, and otherfactors.

Note)

Where some monitoring stations are to be relocated,streamlined by merging and closing, or abolished as a result－ 12 －

of the adjustment, particular attention shall be paid toensuring the continuity of measured data and the efficientmonitoring to represent the specific characteristics of theregions concerned.
(iii)

Adjustment of the number of monitoring stations to correspond to thecharacteristics of monitoring items
The number of monitoring stations shall be adjusted to that
determined in (i) and (ii).

[Informative Commentary]
The required number of monitoring stations from the nationwide perspective
referred to in 2. (1) (A) is determined for Niigata Prefecture and Niigata City as
examples.
Example 1: In the case of Niigata City(i)

Determination on the basis of population and habitable area(a) (Total population = 812,034) 3) ÷75,000㸻10.8(b) (Habitable area = 726.10) 3) ÷25㸻29.0
Since 10.8㸺29.0, the required number of monitoring stations from thenationwide perspective is found to be 10.8.

(ii) Adjustment of the number of monitoring stations according to theenvironmental concentration level
Based on the officially released results in Niigata Prefecture 4) to 6) , theannual average performance index* over the past three years is found not
to exceed the EQSs, although the 24-hour average performance index*
exceeds the EQSs in some places (Table 3). However, comparison of thehighest values for performance indices with 70% of the reference values
provides the results shown below.
Annual average: 15×0.7㸻10.5<13.9 (Shirone Station in FY2012)24-hour average: 35×0.7㸻24.5<37.5 (Kameda Station in FY2013)*

Annual average and 24-hour average performance indices refer to the 98
percentile value of annual average and 24-hour average, respectively. For
further information about calculation methods, refer to “7. Handling andassessment of measured values” in the Paperwork Standards.

－ 13 －

Table 3

PM 2.5 Mass Concentration at Niigata City 4) 㹼 6)
Unit: Pg/m 3 
Evaluation target value

Evaluation target valueof annual averageof daily average

Station name / Year

2011

2012

2013

2011

2012

2013

Kameda

12.1

11.9

12.8

30.5

31.7

3 7.5

Ohyama

-

13.8

12.4

-

32.8

36.4

Tarodai

-

-

12.8

-

-

35.8

Shirone

-

1 3.9

11.9

-

34.5

35.7

Higashi-yamanoshita

-

-

12.7

-

-

32.7

Bold: maximum concentration in each category
Niigata City is a cabinet-designated city, having the monitoring stations fallingunder “High” and thus, it requires the monitoring stations in the number
determined in (i), or 10.8 䴼11. In Niigata City, all the monitoring stations arelabeled as “High.”
Example 2: In the case of Niigata Prefecture(i) Determination on the basis of population and habitable area(a) (Total population = 2,395,139) 3) ÷75,000㸻31.9(b) (Gross area 12583.72×Proportion of habitable area 0.356) 3) ÷25㸻179.1
Since 31.9<179.1, the required number of monitoring stations fromthe nationwide perspective is found to be 31.9, and 21.1 monitoring
stations, obtained by subtracting 10.8, or the required number for
Niigata City, from 31.9, are required for all areas within theprefecture other than Niigata City.
(ii) Adjustment of the number of monitoring stations according to theenvironmental concentration level
Also in Niigata Prefecture, similarly as in Niigata City, the annual
average performance index over the past three years is found not to exceed
the EQSs, although the 24-hour average performance index exceeds the
EQSs in some places (Table 4). In addition, all the performance indices arefound to be equal to or higher than 70% of the EQSs values. Consequently,
Niigata Prefecture is found to be a prefecture having monitoring stations
falling under “High” and therefore it requires monitoring stations in thenumber determined in (i) or 21.1 䴼21.

－ 14 －

Table 4

PM 2.5 concentration in Niigata Prefecture (Except for Niigata City) 4) 㹼 6)
Unit: Pg/m 3 
Evaluation target value

Evaluation target valueof annual averageof daily average

Station name/ Year

2011

2012

2013

2011

2012

2013

Shibata

-

11.3

12.1

-

27.0

31.9

Johoka

12.8

12.3

13.1

30.6

28.4

37.4

Fukaya

-

-

1 4.1

-

-

3 9.2

Bold: maximum concentration in each category

(B)

(i)

Determination of the required number of monitoring stations from theregional perspective
Consideration of natural conditions
The required number of monitoring stations must be determined inconsideration of topographic, meteorological, and other region-specificconditions listed below to meet the conditions.
(a)Topographic conditions
For those areas isolated from other areas by mountains, locatedadjacent to a valley or river/lake and thus exposed to complicatedatmospheric currents, or located on the seaside and subject tohigher wind velocities, in which the atmospheric environments are
independent from those in the other areas, it will not be adequate
to apply the results of monitoring in one city to represent theconditions of atmosphere in another city.

(b)

Meteorological conditions
Atmospheric environments vary with air temperature, winddirection, wind velocity, duration of sunshine, seasonal changes,
and other factors.

(ii) Consideration of social conditions
The number of monitoring stations

must

be

determinedinconsideration of the social usefulness of continuous monitoring in thecontext of making provisions for air pollutant sources, responding to
the needs of communities concerned, identifying the status offulfillment of regulations and planned arrangements, planning future
development, and practical application to various research efforts andinvestigations.

－ 15 －

(a)Making provisions for air pollutant sources
For stationary sources of air pollution, the distribution, scale, andemission point heights of factories and neighboring wind direction
can affect the atmospheric environment.
Especially in areas where factories are densely packed, it should be
noted that quick response is essential in the event of accident orotherunusualconditions.

In

addition,measuredvaluesofsubstances under continuous monitoring allow estimation of thetrend in emission of any air pollutants other than the substances
under monitoring, and therefore continuous monitoring is also
helpful for monitoring the entire air contaminants.
For mobile sources of air pollution, the arrangements or plannedchanges of roads and also the structure of roads, traffic volume byvehicle type, vehicle running speed, roadside conditions, and otherfactors can affect the atmospheric environment.
In urban areas congested with high- and medium-rise buildings,
the atmospheric currents and waste heat from the buildings canaffect the atmospheric environment.
(b)

Making provisions against possible effects of trans-boundary
pollution from the neighboring and/or other prefectures
Monitoring stations must be allocated in consideration of possible
effectsontheinvolved

prefecturetrans-boundary

pollutionfrom

and/orneighboringareas
and/or

of

any
other

prefectures, which would be caused by seasonal and/or weather
conditions.
(c)Responding to the needs of communities concerned
Where there exists an agreement with or request by the community
concerned and/or other social demand for allocation of monitoring
stations, a general consensus must be built.

(d)Identifying the status of fulfillment of regulations and plannedarrangements
Continuous monitoring has an additional role of providing means tocomplement the environmental surveillance conducted by factories,
etc. on a voluntary basis and help the government agencies toperform final verification of proper compliance with regulatory－ 16 －

requirements. Furthermore, in environmental pollution control,
port and harbor planning, and various other programs, continuous
monitoring is actively positioned as a means to check if the
programs are proceeded as planned.
(e)Planning future development
Where large-scale development is planned, prior measurement of
atmospheric environments is essential.

(f)Practical application to various research efforts and investigations
The data accumulated in every monitoring station have beenpractically applied as basic inputs to research and as scientific
data such as average exposure in the health impact assessment in
the vicinity of monitoring stations, thus playing an important role.
Especially in a case where monitoring station data are practicallyapplicable to any environmental impact assessment, it contributes
to increased efficiency in the assessment and enhanced quality of
the assessment by virtue of its advantages of allowing clarificationof changing trends over time and resultantly achieving precision
improvement in forecast evaluation.

(iii)

Consideration of the background to date
The monitoring stations that have been installed for a considerably
long time and involved consistently in measurement have crucial
significancefor

understanding

thechangesinatmosphericenvironments over time. In addition, monitoring stations have often
been regarded highly by the local residents for their usefulness andaccepted as given to the communities. Consequently, the existing
monitoring stations should be continuously maintained by fully
reviewing the background to date and being included in the standard
for preferable number of monitoring stations.
(2)

Allocation of monitoring stations
In accordance with the examples referred to in II - 2. (2) *2 of the Paperwork
Standards, measuring equipment shall be installed in existing monitoring
stations as a rule to meet the need for comparison of nitrogen oxides,
suspended particulate matters, and other items. In practice, however,proper installation position shall be selected taking into consideration therequirements for installation of sampling inlets described in Section 5.

－ 17 －

*2

The number of monitoring stations determined based on the provisions in(1) refer to the preferable total number of monitoring stations in eachprefecture. Specific points for allocation of the monitoring stations shall beproperly selected by individual prefectures and cabinet-designated cities
based on the nationwide and regional points of view, which have been
applied for determination of the number of monitoring stations. The
monitoring stations may be grouped into two types listed below and then,appropriate type of stations shall be installed for the actual conditions ofindividual regions, giving consideration to the description provided below.
(i)Ambient air quality monitoring station
This monitoring station is intended for continuous monitoring of thestatus of air pollution. All the monitoring stations other than theroadside air quality monitoring stations referred to in (ii) below arecalled ambient air quality monitoring stations. The ambient air quality
monitoring stations shall be allocated to efficiently attain the purposesof continuous monitoring, including continuous understanding of thestatus of air pollution in a certain area, identification of contribution ofemissions from sources to pollution and heavily polluted areas, andunderstanding of the effectiveness of solutions taken for prevention of
air pollution.

(ii)

Roadside air quality monitoring station
A monitoring station intended to continuously monitor the status ofair pollution at an intersection, over a road, or on the roadsideresulting from emissions from running vehicles is referred to as aroadside air quality monitoring station. The roadside air quality
monitoring stations shall be properly allocated in consideration of theconditions of road and traffic volume to allow efficient monitoring of
air pollution due to exhaust gases from motor vehicles.
At the properly allocated monitoring stations, monitoring shall be
continued consistently at the same spot as a rule to help identify any
changes over time.

(3)

Phased improvement
For the monitoring stations, the number of which has been determinedbased on the provisions in (1), improvements shall be carried out, taking－ 18 －

about three years from FY2010.
3.

Frequency of monitoring

Monitoring shall be carried out consistently as a rule throughout the year.
4.

Height of sampling inlets(1)

Basic concept
Air samples shall be taken as a rule at a height at which people live theirnormal lives and breathe.

(2)

Based on the basic concept, specific height for sampling for monitoring of
PM 2.5 shall be in accordance with the examples referred to in II - 4. (2) to(4) of the Paperwork Standards for suspended particulate matter (SPM) *3 .

*3 (2)

Based on the basic concept, the specific height of sampling inlets
shall be 3 m or more and 10 m or less above the ground for thesuspended particulate matter to eliminate possible effects such as
sand and earth blown up in the air from the ground.

(3)

When the height in (2) is found inappropriate as a result of careful
investigation of the actual conditions based on the basic concept due
to the situation where many people are living at height of 10 m or
more above the ground such as in a high-rise collective residentialbuilding, proper height shall be selected as appropriate for the actual
situation.

(4)

Where the provisions in both (2) and (3) cannot apply or they arefound inappropriate due to unavoidable circumstances such asdifficulty in securing proper installation sites, the best possible effort
should be made to establish a sampling inlet that meets both of therequirements listed below.
(A)(B)

The height of sampling inlet does not exceed 30 m; andCompared to the results of monitoring conducted at aneighboring spot continuously for one month or more at thesame height of sampling inlet as specified in (2), any average
difference in the 24-hour average of hourly values does notexceed 1/10 of the lower limit of air quality standard.

In practice, in order to identify any effects of seasonal changes, the－ 19 －

concurrently conducted monitoring shall be repeated at least fourtimes a year in the four different seasons.
5.

Requirements for installation of sampling inlets

In order to prevent possible loss of PM 2.5 due to adsorption and/or other reasons,the sampling inlet and the particulate collection section shall be connected witheach other through a vertical tube, and the distance between the sampling inlet
and the particulate collection section shall be limited to 5 m and the distance
between the outlet of particle size classifier and the particulate collection
section limited to 1.5 m. Where a sampler is installed in the inside of amonitoring station, the sampling tube shall be installed through the ceiling of
the station.
In addition, around the sampling inlet, sufficient open space shall bemaintained. Where any other sampling inlets, sampling equipment, and/or
other installations exist in the surroundings, the sampling inlet shall preferably
be located at least 1 m distant from the installations, in order to avoid possible
effects[Informative Commentary]
Figure 2 shows concept of 4.(2) and 5..

Figure2

Installation

requirementsfor

PM 2.5
7)

automatic monitor (Example for outdoor installation) 㻌－ 20 －

6.

Measuring methods

The standard measuring method or automated measuring equipment recognized
to provide equivalent values to mass concentration measured by the standard
measuring method shall be used. For any other measuring methods and thespecifications and configuration of measuring equipment, reference shall bemade to the “Manual for Continuous Monitoring of Air Pollution”
7.

Handling and assessment of measured values(1)

Measured values not subject to assessment(A) Measured values obtained in the monitoring stations located in
exclusive industrial districts specified by the City Planning Law(including the exclusive industrial districts designated by the former
City Planning Law), harbor/port areas specified by the Port andHarbor Law, and vehicle running sections of roads, reclaimed lands,
wastelands, volcanic regions, and other areas and locations where
people may not live normally.
(B)

Any measured values which are verified not to accurately reflect thestatus of air pollution in the area concerned due to reasons caused by
the measuring equipment, etc.

(C)24-hour average obtained with measurement of such average missed
for a total of four hours or more in a day (24 hours). Annual averagecalculated with the number of days of valid measurement not reaching
250 days.

－ 21 －

[Informative Commentary]
Figure 3 shows concept of calculation in 7.(1)(c).
Annual average shall be calculated by using data from 1st April through 31 st March.


1-hour average of a certain hour is defined as the average value from the
beginning of the previous hour to the beginning of that hour 8) . Daily average
shall be calculated as the average of 1-hour average from 0 to 24 o’clock8) .

Day/ Month/

1

2

3

22

㹼

23

24

24 hourYearaverage

1/4/2014

10.5

10.5

10.5

10.5

10.5

10.5

10.5

10.5

2/4/2014

10.5

10.5

10.5

10.5

lack

10.5

10.5

10.5

30/3/2015

lack

lack

lack

10.5

lack

lack

10.5

Missing

31/3/2015

lack

lack

lack

10.5

lack

10.5

10.5

10.5

Annual average

-

-

-

-

-

-

-

10.5

㹼

When there are four or more missing 1-hour averages, daily average shall be missing.
When the number of day with valid data is less than 250, annual average shall be missing.

Figure 3
(2)

Calculation method of daily and annual averages

Assessment of results of continuous monitoring
In accordance with both the long-term guidelines for normal reduction of
the entire distribution of particulate matter 2.5 (PM 2.5 ) exposure
concentrations and the short-term guidelines for reduction of occurrence of
higher concentrations in the distribution of exposure concentrations,long-term assessment shall be conducted.
Assessment in accordance with the long-term guidelines compares theannual average of measured results with the long-term guidelines (annual
average).
Assessment in accordance with the short-term guidelines selects the annual
98 percentile value of 24-hour average of measured results as arepresentative value for comparison with the short-term guidelines (24-hour
average). The assessment shall be conducted for each monitoring station.
For judgment on whether or not the EQSs are met, assessment inaccordance with the long-term and short-term guidelines is individuallyconducted and then the stations found to satisfy both guidelines are defined
as meeting the EQSs.

－ 22 －

[Informative Commentary]
Figure 4 and Table 5 show concept of 98 percentile value and an example ofachievement of EQSs.

The 98 percentile value is defined100%

as the 98 percent value from theminimum value of daily average

The second maximum

ina certain

year. Whenthenumber of effective day is 360,98%

the 8 th highest daily average
shall be accepted. The calculation

minimumЍЋLine of the daily averages from maximum to

The maximum daily average

equation is shown as follows.
360 (days)  0.98 㸻 352.8 Ҹ 353(days)
360 (days)㸫353 (days)㸻7 (days)(The 7 days data from the top are
eliminated and the 8 th data shallbe accepted as the 98 percentile

The second minimum

value.)The minimum daily average

Figure 4

Table 5Concept of 98 percentile value

Example for judgment on Environmental Quality Standards (EQSs)
Annual98 percentile value

averageof daily average

A

15.0

35.0

Achievement

B

15.1

35.0

Non-achievement

C

15.0

35.1

Non-achievement－ 23 －

Judgment on EQS

8.

Component analysis(1)

PurposeComponent analysis is carried out in addition to measurement of massconcentration in order to amplify knowledge for contribution to surveys on
possible health impact of PM 2.5 and seek more efficient solutions based on
the accumulated scientific knowledge about the causative substances
through understanding of the status of emission, development of emission
inventory, and clarification of behavior in the air and mechanisms forsecondary products formation.

(2)

Systems for implementation
Component analysis must be adopted systematically on a nationwide scale
and therefore it should be conducted successively based on the guidelines
established separately to determine the role sharing between the central
government and the prefectures, the methods for selection of the (numberof) points for analysis, and the timing and methods of investigation.

9.
For

Quality assurance/quality control (QA/QC) and maintenancemeasurement

withgreaterprecision,apropermaintenanceandmanagement system shall be established and improved in accordance with the“Manual for Continuous Monitoring of Air Pollution” to ensure that appropriate
daily, regular, and other inspections and maintenance are carried out for themeasuring equipment and details of the inspection and maintenance areproperly recorded.
10.

Reporting of results

Reporting of the results of continuous monitoring in accordance with the Air
Pollution Control Law shall be completed before the specified date based on themethod specified independently by the Ministry of the Environment.

－ 24 －

4

Distribution of PM 2.5 monitoring stations in Japan

Since establishment of environmental quality standard in September 2009, thenumber of PM 2.5 monitoring stations and the number of sites conducting component
analysis in Japan have been increasing year by year.
4.1

Changes in the number of PM 2.5 monitoring stations

The total number of PM 2.5 monitoring stations, including National Kitanomaru
roadside air quality monitoring station (hereinafter referred to as “roadsidemonitoring station”), one of the stations exempted from application ofenvironmental quality standard, and the monitoring stations using themeasuring equipment without any equivalence, reached 73 as of the end of
FY2010 (45 ambient air quality monitoring stations and 28 roadside monitoring
stations) 9) and 310 as of the end of FY2011 (223 ambient air quality monitoring
stations and 87 roadside monitoring stations) 10) , showing an about four-foldincrease at the end of FY2011 from the end of FY2010 (about five-fold increase in
the number of ambient air quality monitoring stations and about three-foldincrease in the number of roadside monitoring stations). As of the end of FY2012,
the number of monitoring stations amounted to 596 (429 ambient air quality
monitoring stations and 167 roadside monitoring stations) 11) , showing an about
eight-fold increase from the end of FY2010 (about ten-fold increase in thenumber of ambient air quality monitoring stations and about six-fold increase in
the number of roadside monitoring stations). However, the target number ofmonitoring stations determined based on the guidelines provided in the
Paperwork Standards is 1,292 1) and therefore, the number of the actually
installed monitoring stations is found to be far short of half of the target number,even when including the measuring equipment without equivalence.
Distribution of PM 2.5 monitoring stations in each fiscal year by measuring
equipment with and without equivalence is provided in Figure 5.

－ 25 －

Figure5

Distributionof

PM 2.5 monitoring stations㻌
A: 73 stations in 2010, B: 310
stations

in

2011,

C:

596

stations in 2012㻌‫ ۑ‬:

stationswith

PM 2.5monitor whose equivalence tothestandard

methodconfirmed, ‫ە‬: Others

4.2

is
㻌

Changes in the number of sites conducting the component analysis of PM 2.5

Component analysis was once implemented by the Ministry of the Environment,
Japan (MOEJ) up to FY2010 as the “Particulate Matter 2.5 (PM 2.5 ) Exposure
Impact Assessment” at a total of 14 sites throughout the country, but it was
discontinued during that fiscal year. In FY2011 MOEJ and local governments
newly incorporated component analysis in the continuous monitoring inaccordance with “The processing standards for administrative affairs forcontinuous monitoring of air pollution based on the Air Pollution Control Law”
referred to in Chapter 3. The number of investigation spots increased as of theend of FY2012 compared to the end of FY2011, similarly as with the number of
automated monitoring stations. Table 6 provides the number of monitoring sites
by type of site 12), 13) . The figures in parentheses in the table represent the－ 26 －

number of sites at which monitoring was conducted for a duration of two weeks
or so in each of the four seasons throughout the fiscal year in accordance with the
Guideline for Component Analysis described (hereinafter referred to as“four-season monitoring”). As can be seen from the table, the number ofmonitoring sites was increased from 35 to 52 for the ambient air quality
monitoring stations, showing an about 1.5 times increase, from 15 to 24 for theroadside monitoring stations, showing an about 1.6 times increase, and from 8 to
12 for the background monitoring, showing a 1.5 times increase. For the sites atwhich the four-season monitoring was conducted, the total number was morethan doubled, to 67 from 31.
Regarding the sites at which component analysis is conducted, the Guideline for
Component Analysis states that sample collection points should be selectedbasically from (i) continuous monitoring stations of PM 2.5 and then (ii) the sites
with higher PM 2.5 concentration and the sites allowing identification of
background concentration. However, the Guideline also states that (iii) it is notmandatory to carry out component analysis in the background. Monitoring in theambient air and roadside monitoring stations is almost all conducted under the
responsibility of local governments, but at eight of a total of 12 background sites
in FY2012, the MOEJ is involved in the monitoring (Nonodake, Ogasawara,
Shionomisaki, Tsushima, Goto, Oita Kuju, Yakushima, and Hedomisaki) andonly the remaining four sites rely on the local governments.
Table 6

Number of station performing components analysis in each classification10), 11) (The number of station performing 4 season’s analysis)

Classification

2011

2012

Ambient

35 (18)52 (44)

Roadside15 (11)24 (19)Background8 (2)12 (4)Total

58 (31)88 (67)－ 27 －

5

Types and the actual number of pieces of automated measuring equipment in
operation in Japan

As mentioned in Chapter 2 “Assessment methods and assessment results ofequivalence between the automated PM 2.5 measuring equipment and the standard
measuring method (filter sample collection method),” in Japan, in order to evaluate
whether or not the environmental quality standard (EQS) is met, the automatedmeasuring equipment recognized to provide measured results equivalent to thosegained from the standard measuring method must be used for measurement of
PM 2.5 . In actuality, however, in some sites, including the national air pollution
monitoring stations, there exist automated measuring equipment withoutequivalence, which was introduced before establishment of EQS, and so theirmeasured values are released as reference data. Table 7 provides the working
situations of automated measuring equipment.
Table 7  Operational status of automated PM 2.5 equipment *1
Model

Equivalent test

PM-712Passed

PM-717

PassedFPM-377

PassedManufacturer
Kimoto Electric
DKK-TOA

2010

2011

2012

0

67

140

0

0

0

6

111

240

21

26

33

0

53

131

25

33

36

0

0

0

CORPIRATION
APDA-3750A

PassedHoribaFH62C14

PassedSHARP5030

Passed5014i

PassedMP101M

PassedEnvironnement S.A

0

0

0

TEOM1400,

FailedOthers22

20

16

Thermo Fisher
Scientific

etc.
㸫
㸫
Total
74 *2
310
596
*1 This table is completed by the interview survey to local governments afterreferring “The report of air pollution monitoring results in 2012” (MOEJ, July2014) and “Data about monitoring stations (status over Japan in 2012)” on the
NIES Environmental Numerical Database.
*2 The number of monitoring station is 73 (Figure 5) in 2010, however, thenumber of equipment is 74 because parallel monitoring was carried out at
National Osaka Air Quality Monitoring Station. The parallel monitoring had
been continued after 2011 at the station, however, since the aggregation of thenumber of station had been done equipment basis in the source reports after
2011, same numbers as Figure 5 are shown in this table.

－ 28 －

6

Methods for releasing monitoring data

The Basic Environment Act stipulates implementation of research efforts andprovision of information, and the Air Pollution Control Law stipulates continuous
monitoring and releasing of results by local governments as summarized below.
Under these laws, local governments make it obligatory by the municipal
ordinances to implement research efforts and submit reports. As examples, someprovisions of the ordinances of Niigata Prefecture and Niigata City are extracted
below.
In recent years, the expansion of Internet accessibility has enabled the release of
preliminary figures and/or report documents through websites. Typical contents
released by the Ministry of the Environment, Japan (MOEJ) and local governments(Niigata Prefecture and Niigata City as examples) are reproduced later in thischapter.

The Basic Environment Act(Provision of Information)
Article 27 The State shall make efforts to appropriately provide necessary
information on environmental conservation including the state of
the environment, so as to promote the education and learning
provided for in Article 25 and to contribute to the activities
voluntarily conducted by the private bodies etc., provided for in thepreceding Article, in consideration of the protection of the rights
and benefits of individuals and legal entities.
(Implementation of Researches)
Article 28 The State shall conduct surveys on the state of the environment,
researches on forecast of environmental changes and other studies
forformulationofpolicies

conservation.

－ 29 －

withregardtoenvironmental

Air Pollution Control Law(Continuous Monitoring)
Article 22 Prefectural governors shall continuously monitor the status of air
pollution (air pollution caused by radioactive materials not included;
the same applies for paragraph 1 of Article 24) in accordance with an
Ordinance of the Ministry of the Environment.
2. Prefectural governors shall report the results of the continuous
monitoring under the preceding paragraph to the Minister of theEnvironment in accordance with an Ordinance of the Ministry of theEnvironment.
(Public Announcements)
Article 24 Prefectural governors shall make public the status of air pollution
within the prefecture in accordance with an Ordinance of the
Ministry of the Environment.
(Affairs Handled by Mayors of Cities Specified by Cabinet Order)
Article 31 A part of the affairs that are under the authority of a prefectural
governor pursuant to the provisions of this Act may be undertaken by
the mayor of a city (including special wards; the same shall apply
hereinafter) specified by a Cabinet Order pursuant to the provisionsof a Cabinet Order.
Enforcement Order of the Air Pollution Control Law(Affairs Handled by Mayors of Cities Specified by Cabinet Order)
Article 13 2. Of the administrative affairs under the authority of a prefectural
governorpursuant

totheprovisions

of

the

Law,

(…)

the

administrative affairs related to monitoring pursuant to theprovisions of Article 20 of the Law, the administrative affairs related
to requests pursuant to the provisions of paragraph 1, Article 21 of
the Law and related to statements of opinion pursuant to theprovisions of paragraph 2, Article 21 of the Law, the administrative
affairs related to continuous monitoring pursuant to the provisions ofparagraph 1, Article 22 of the Law and related to reporting pursuant
to the provisions of paragraph 2, Article 22 of the Law, and theadministrative affairs related to public announcements pursuant to
the provisions of Article 24 of the Law (…) shall be undertaken by themayor of a city ᇲᇲ, (…) (hereinafter referred to as “mayor of acabinet-designated city”).

  － 30 －

Niigata Prefecture Basic Environment Ordinance(Annual Reporting)
Article 8 The Prefectural Governor shall submit annually to the Prefectural
Assembly a report on the state of the environment and the policies
with regard to environmental conservation and release the report.
(Implementation of Study and Research, etc.)
Article 17 The Prefecture shall, in order to establish and properly implement
the policies for conservation of the environment, make efforts tocollect information, implement studies and research efforts, anddevelop technologies and spread the products of the technology
development

regardingthematters

relatedtocontrolofenvironmental pollution, preservation of the natural environment,
and conservation of the global and other environments.
(Improvement of Systems for Monitoring, etc.)
Article 18 The Prefecture shall make efforts to establish systems of monitoring,measurements, examinations, and inspections, etc. in order toascertain the state of the environment and properly implement thepolicies with regard to environmental conservation.
Niigata City Basic Environment Ordinance(Annual Reporting)
Article 7 The Mayor shall submit an annual report on the state of theenvironment

and

the

policieswithregardtoenvironmental

conservation and release the annual report.
(Identification of the Status of Environment, etc.)
Article 18 The City shall make efforts to collect information and implement
studies and research efforts in order to ascertain the state of theenvironment and properly implement the policies with regard toenvironmental conservation.
2 The City shall make efforts to establish systems of monitoring andmeasurements, etc. in order to ascertain the state of the environment
and properly implement the policies with regard to environmental
conservation.

－ 31 －

6.1

Ministry of the Environment, Japan (MOEJ)

6.1.1

Release through written reports

MOEJ has been publishing annually the “Annual Report on the Environment,
the Recycling-oriented Society and the Biodiversity in Japan” since FY2009 to
make public the results including the entire environmental administration in
Japan with regard to air pollution, water contamination, and waste treatment
in conjunction with the results of the policies for establishment ofrecycling-oriented society and conservation of biodiversity. Before FY2009, theAnnual Report had been published in the form of “White Paper on
Environmental Pollution” (FY1969 to FY1971), “White Paper on Environment”(FY1972 to FY2006), and “White Paper on the Environment and the
Recycling-oriented Society” (FY2007 and FY2008).
In addition to the Annual Report, the “Report on the State of Air Pollution” ispublished annually as a specific report relating to continuous monitoring of air
pollution and distributed to organizations concerned such as individual local
governments to report the results of continuous monitoring of the status of air
pollution all over the country. This Report contains the rate of compliance withthe environmental quality standards (EQSs) for individual monitoring items,
annual average, changes over time, and other statistics in Part 1 “Results ofcontinuous monitoring of the status of air pollution” and also the valid
measurement time at individual monitoring stations (the number of days
during which valid measurements could be obtained for PM2.5 ), annual average,
and the annual averages over the past ten years in Part 2 “Reference Data.”
6.1.2

Release through website

There is a website listing real time data of air pollutant concentrations
measured throughout the country for public announcement (Atmospheric
Environmental Regional Observation System (AEROS), Figure 6). This site
provides information on a 24-hour basis by compiling not only the data ofcontinuous monitoring from MOEJ and local governments but also the datafrom the national acid rain observatories (only those registered for EANET),
which is not included in the continuous monitoring, and yellow sand (DSS)
observation data obtained through the telemetered network. The data on PM 2.5
and other air pollutants is presented by regional division in Japan (Figure 7),
and the distribution of hourly concentration values in each region may beviewed retroactively to 168 hours ago (seven days). In addition, a summary of－ 32 －

hourly values for all the monitoring items by monitoring station and thetime-series plot graphs for individual monitoring items may also be accessible,
being traced back to 168 hours ago.
In actuality, however, the real time data on this website are updated with adelay of about two hours and so, for identifying the most recent data, it isnecessary to visit the website of the local government concerned. The websiteof MOEJ contains a page offering a summary of information about PM 2.5 andlisting the links to the above-described page providing the real time data, thepage for modeling, the pages including topics, pages referring to The EQSs,
and provisional guidelines for raising an alert, and an additional page
providing a list of links to real time data for individual prefectures to provide
the current status, which allows immediate access to the necessary local
government websites (Figure 8).
Final fixed data are announced officially on the website of the National
Institute for Environmental Studies (NIES) (Figure 9). The published data on
PM 2.5 include hourly values, monthly averages, and annual averages by fiscal
year since FY2009. In addition, for the continuous monitoring stations forambient air quality, detailed information is compiled by fiscal year, and for
PM 2.5 , the information about whether or not the measurement was successfullycompleted, the type of measuring equipment used, and whether or not themeasuring equipment has proper equivalence is contained. These files aredownloadable from the website in the text file format. The data by fiscal year
and the information about monitoring stations become downloadable once thereport for the fiscal year concerned has been released on the website for publicannouncement. NIES publishes the nationwide distribution of annual values
based on the final fixed data (Figure 10). Graphical representation on thewebsite is provided on a scale of 1 to 200 km, which may be enlarged to a scaleof 1 to 100 m, allowing detailed checkup of the status of surroundings. Data
before FY2008 may be downloaded from the website of MOEJ (Figure 11),although the data include measured values with any missing data left
unprocessed and therefore it should be treated as reference information.
㻌㻌－ 33 －

㻌
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Figure 6㻌

MOEJ (access on September 5, 2014) http://soramame.taiki.go.jp/

Front page of real time data provision site managed by－ 34 －

Figure 7

An example of regional page (Kanto region) of real time data provisionsite (access on November 13, 2014) 㻌http://soramame.taiki.go.jp/DataMap.php?BlockID=03－ 35 －

Figure 8

Front page of “Information of PM 2.5 ” on the website of MOEJ (access on

December 11, 2014) http://www.env.go.jp/air/osen/pm/info.html－ 36 －

Figure 8 (Continued)

Webpage of “Information of PM 2.5 ” on thewebsite of MOEJ (linked to the webpage of local governments,
access on December 11, 2014)－ 37 －

Figure 9

Front page of “Database of environmental numerical data” on thewebsite of National Institute for Environmental Studies, Japan (NIES)(download site for final fixed data, access on September 5, 2014)
http://www.nies.go.jp/igreen/

Results of component analysis are downloadable from the website of MOEJ
(Figure 11). From the “FY2010” to “FY2012” links on this website, the resultsof component analysis can be downloaded. For the results of component
analysis, only the final fixed data are released.

－ 38 －

Figure 10

An output of continuous air pollution monitoring in theEnvironmental Geographic Information System on the website of NIES
(distribution map of final fixed PM 㻞㻚㻡 data in 2011JFY, access on September 5,2014)

http://tenbou.nies.go.jp/gis/monitor/?map_mode=monitoring_map&field=2－ 39 －

Figure 11

Front page of “Measurement data of PM 㻞㻚㻡 ” on the website of MOEJ

(access on December 11, 2014) http://www.env.go.jp/air/osen/pm/monitoring.html

The “Annual Report on the Environment, the Recycling-oriented Society andthe Biodiversity in Japan” and the “Report on the State of Air Pollution”
referred to in the preceding section are also downloadable from the website.
However, Part 2 “Reference Data” of “Report on the State of Air Pollution”(annual values by monitoring station, etc.) are not posted on the website.
Therefore, for acquisition of the data, it is necessary to submit a request to the
MOEJ or download the data from the website of the NIES (Figure 9) in theform of a text file different from the original format.

－ 40 －

6.2

Niigata Prefecture

6.2.1

Release through written reports

Similarly to MOEJ, Niigata Prefecture publishes annually “The Environmentof Niigata Prefecture” (White Paper on Environment) and “Report on the
Monitoring Results of Air Pollution.” The FY2014 edition of “The Environmentof Niigata Prefecture” was issued on September 24, 2014 and the “Report on
the Monitoring Results of Air Pollution” will be released at the end of the fiscal
year.
6.2.2

Release through website

Niigata Prefecture also makes public the real time data (Figure 12: hourly
value, Figure 13: 24-hour average) in addition to “The Environment of Niigata
Prefecture” and “Report on the Monitoring Results of Air Pollution” mentioned
in the preceding section. In addition, how any alerts are raised is made known
to the public (Figure 14), and whether or not an alert is currently raised may
be identified on the website listing real time data (Figure 12).
Meanwhile, the results of compliance with the EQSs in FY2012 are released,
although the final fixed data of hourly values and 24-hour averages are left outof public announcement.

－ 41 －

Figure 12

Front page of “Current status of atmospheric environment (realtime data) in Niigata Prefecture” on the website of Niigata Prefecture, Japan(access on September 24, 2014) http://www.niigata-taiki.jp/－ 42 －

Figure 13

Front page of PM 2.5 real time data provision site managed by Niigata

Prefecture, Japan (real time data of daily average, access on September 24, 2014)
http://www.pref.niigata.lg.jp/kankyotaisaku/1356750033048.html

Figure 14

Front page of “Measures for the high concentration event of PM 2.5 ”

on the website of Niigata Prefecture, Japan (procedure for alert, etc., access on
September 26, 2014)
http://www.pref.niigata.lg.jp/kankyotaisaku/1356753592105.html－ 43 －

6.3

Niigata City

6.3.1

Release through written reports

Similarly to Niigata Prefecture and MOEJ, Niigata City also publishes anannual report titled “The Environment of Niigata City,” releasing the state of
the environment and the performance of the policies with regard toenvironmental conservation. However, such detailed data as disclosed in the“Report on the Monitoring Results of Air Pollution” are not published, but “TheEnvironment of Niigata City (Summary Statistics)” is simply posted on thewebsite for public announcement. The annual report is published usuallyaround October and the Summary Statistics is released usually during thenext fiscal year.
6.3.2

Release through website

In Niigata City, in addition to the annual report and the Summary Statistics
mentioned in the preceding section, real time data (Figure 15: hourly value,
Figure 16: 24-hour average) and concentration distribution map based on thereal time data (Figure 17) are released. Real time data of hourly values may be
traced back to the data in the past half-year for viewing. In addition, how any
alert is raised is made known to the public (Figure 18), and the current statusof alert is announced officially on the website.

－ 44 －

㻌㻌

Figure 15

Webpage of real time air concentration data provision sitemanaged by Niigata City, Japan (hourly average, access on
September 24, 2014) http://taiki.city.niigata.lg.jp/newsflash.php㻌－ 45 －

Figure 16

Webpage of PM 2.5 measurement data provision site managed by

Niigata City, Japan (daily average, access on September 24, 2014)
http://www.city.niigata.lg.jp/kurashi/kankyo/seikatukankyo/taikikankyo/kan
kyo_pm2_5_result.html－ 46 －















Figureconcentrations (real time data)” on the website of Niigata City, Japan(hourly average of PM 2.5 , access on September 24, 2014)

http://taiki.city.niigata.lg.jp/newsflash_kankyo.php17Webpageof“Distribution

－ 47 －

map

of

air

pollutantFigure 18

Webpage of “Information of PM 2.5 ” on the website of Niigata

City, Japan (procedure for alert, etc., access on December 11, 2014)
http://www.city.niigata.lg.jp/kurashi/kankyo/seikatukankyo/taikikankyo/
kankyo_pm2_5.html－ 48 －

7

Provisional Guideline for Raising Alerts
7.1 Positioning of the guideline
Although there are limited findings in Japan and abroad about the health impactof PM 2.5 through short-term exposure, a wide range of studies have been carriedout on its relationship with changes in cardiovascular and respiratory functions,changes in respiratory symptoms and respiratory functions, number of times of
hospitalization/consultation at medical institutions, changes in outpatient
emergency consultations, and death through respiratory/circulatory diseases.
Of these, the results of epidemiological research showing significant correlation
between the 24-hour average concentration of PM 2.5 and hospitalization/
consultation for respiratory/circulatory diseases showed that there was someform of health impact at the 98 percentile value of a 24-hour average of 69μg/m 3
amongst groups that included highly sensitive persons.
On the other hand, according to the results of tests conducted on volunteer
healthy adults for acute exposure to PM 2.5 , it was found that two hours of
exposure to an average concentration of 72.2μg/m 3 caused changes to the bloodbiochemical index. However, there are also other findings where changes in bloodpressure, heart rate, and other factors were not detected even after exposure toan average concentration of 190μg/m 3 . Hence, a definite correlation has not beenfound between the exposure concentration of PM 2.5 and health impact.
The experts’ meeting proposed a 24-hour average of 70μg/m 3 as a suitable value
for the provisional guideline for raising alerts based on a comprehensive
consideration

of

the

following:

epidemiologicalfindings,

findings

about

short-term exposure, and the fact that the United States’ Air Quality Index (AQI)
have established 65.5μg/m 3 and above as the concentration level at which PM 2.5
may possibly have some form of impact on human health for all people.
However, it is important to note that exposure to PM 2.5 at a concentration
exceeding the 24-hour average of 70μg/m 3 may not necessarily have an impact on
the health of all people.
Even when highly sensitive persons such as those with respiratory/circulatory
diseases, young children, and the elderly, etc. are exposed to a 24-hour average of
below 70μg/m 3 , short-term impact on the health may still be detected.

－ 49 －

7.2

Methods for determining the raising of an alert

An alert is raised in order to draw attention from the general society to reference
information, and to allow the general public, including highly sensitive persons,to use the information as reference for their actions so that they may gain more
opportunities to engage in outdoor activities during the day. Hence, it isconsidered appropriate to raise the alert at an early timeslot in the morningwhen many people commence their daily activities.
In addition, it is considered appropriate to make a decision to raise an alert when
the PM 2.5 concentration for the day is expected to exceed the 24-hour average
concentration of 70μg/m 3 at general ambient air monitoring stations.
It is appropriate to use the hourly value as the measurement for determining
whether or not to raise an alert. However, although it has been proven that
automated measuring equipment for PM 2.5 provides measurements of 24-hour
average concentration that are equivalent to standard measuring methods, theequipment has not been proven to have the ability to produce the same degree of
accuracy for hourly values. For that reason, when hourly values are used todetermine whether or not to raise an alert, it is necessary to put extra effort into
enhancing the accuracy of the hourly value. This can be achieved throughmethods such as computing the hourly average for several hours based on values
collected from multiple monitoring stations, or obtaining the median value.
Using data obtained from general ambient air monitoring stations in all parts ofJapan for two years (FY2010 and FY2011), a study was carried out to elucidate therelationship between the 24-hour average value and the hourly average for 5:00 a.m.,
6:00 a.m., and 7:00 a.m. of the same day. The results of the study are shown in
Figure 19. Based on this regression formula, the hourly value that corresponds withthe 24-hour average of 70μg/m 3 was estimated to be approximately 85μg/m 3 .

－ 50 －

Figure19

Results of regression analysis between the 24-hour averagevalues and 3-hour (5-7AM) average values of the same day㻌The bold line represents the regression famula that shows therelationship between the 24-hour average value and 3-hour averages.
The broken lines show the 95% prediction limits.㻌
Then later, after several local governments requested response to the rise inconcentration in the daytime, in November 2013 considerations were added for
activities to be conducted in the afternoon. Upon considering the possibility ofmaking reassessment after noon using regression analysis of the 24-hour
average and the average of hourly values, 80 Ǎg/m 3 , the average of hourly values
taken between 5 o’clock in the morning and noon was determined as thecriterion.
In December 2014, the following two points were revised. Firstly, the method ofdetermining whether to lift an alert was added so that the residents do not haveto continuously stay indoors in the case where the concentration of PM 2.5 hassignificantly improved in the daytime. Specifically, if the hourly value of PM 2.5
concentration has consecutively fallen below 50 Ǎg/m 3 at all monitoring stations
in a single area where the concentration has exceeded the criterion for raising analert, it was deemed appropriate to determine whether to lift the alert inconsideration of the density transition at the relevant monitoring stations aswell as neighboring monitoring stations. Secondly, the values used for
determining whether to raise an alert in earlier hours of the morning waschanged in order to reduce the chance of “overlooking” the value exceeding theprovisional indicator value before an alert is raised. This means that whether or
not to raise an alert is determined by “the second largest value in a single area”－ 51 －

rather than “the median in a single area,” which used to be regarded appropriate.
Also, raising an alert is something that should be determined daily, so it was
additionally decided that an alert should not be continuously used after
midnight.
With regard to the above-described criterion, it is to be noted that forecast
precision is still limited, in that a certain number of cases are overlooked andthat there are still problems with precision of the automated measuring
equipment concerning the hourly value. For this reason, it is appropriate todetermine whether to raise and lift an alert after taking comprehensive accountof weather conditions, characteristics of pollution sources, etc. in the area,
observation data of neighboring monitoring stations and those in neighboring
prefectures, the latest simulation results released by research institutions, etc.
7.3Provisional guideline for raising alerts

In view of the above, it was considered appropriate to establish the following as
the provisional guideline for raising alerts (Table 8).

－ 52 －

Table 8

Level

ϩ

Ϩ

Environmental
QualityStandard

Provisional guideline for raising alerts

Value for assessing whether or not
to raise an alert *3
Assessment in
Provisional
Assessment in
preparation for
guideline value
the early hours
activities after
Guideline for activitiesof the day
noon time
5:00 – 7:00
5:00 – 12:00
24-hour average
Hourly value
Hourly value(μg/m 3 )(μg/m 3 )(μg/m 3 )As far as possible,
reduce the incidence of
non-urgent outings andstrenuous exercises
outdoors.
(Highly sensitive
Above 85
Above 80
Above 70
persons *2 should takeeven greater care with
their activities inconsideration of thephysical condition of
their bodies.)
While there is no
particular need toBelow 70
restrict activities,
highly sensitive persons
Below 85
Below 80should pay attention tochanges in the physicalcondition of their bodies
Below 35 *1
as health impact may beobserved.

The short-term environmental quality standard is a 24-hour average of 35μg/m 3 ,which is assessed at the 98 percentile value of 24-hour values for a year.
㸨2 Highly sensitive persons includes those who suffer from respiratory/circulatory
diseases, young children, and the elderly.

㸨1

㸨3

The 24-hour average that serves as the provisional guideline is the value used toassess the situation in early hours of a day.

7.4Enforcement methods

In principle, the implementing entity for raising alerts is the municipality. This
is in consideration of factors such as the possibility that a rise in PM 2.5
concentration may occur over a relatively wide area, and the ability of local
government bodies to utilize knowhow about emergency measures based on the
Air Pollution Control Act.
Furthermore, as it is necessary to bear in mind the possibility of a wide-areaphenomenon and the accuracy of measuring equipment, it is appropriate to makea decision about raising an alert using data for several hours obtained from－ 53 －

multiple monitoring stations.
After raising an alert, if significant improvements are observed in the PM 2.5
concentration levels, use the level of 50μg/m 3 as shown in Figure 19 as a
guideline for notifying residents about the improvements.

－ 54 －

References
1)

Japan Environmental Sanitation Center (JESC) “Essential Basic Knowledge
about PM 2.5 ” (May 2013)

2)

MOEJ “Particulate Matter 2.5 (PM 2.5 ) Measuring Method Advisory Committee
Report under Air Environmental Section, Central Environment Council”(September 2009)

3)

Niigata Prefecture website “1. Topography and Population”
http://www.pref.niigata.lg.jp/tokei/1249502654105.html
1. Topography and Population (Excel format 38 KB) (access in November 10,
2014)

4)

Niigata Prefecture Department of Civil Life and Environment, Environment
Control Section “FY2011 Report on the Monitoring Results of Air Pollution”(December 2012)

5)

Niigata Prefecture Department of Civil Life and Environment, Environment
Control Section “FY2012 Report on the Monitoring Results of Air Pollution”(February 2014)

6)

Niigata Prefecture website “The status of achievement of environmental
quality standard for particulate matter 2.5 (PM 2.5 ) (FY2013)”
http://www.pref.niigata.lg.jp/kankyotaisaku/1356750033048.html (access inNovember 10, 2014)

7)

JICA FY2014 “Project for Capacity Development of Planning for Pollution
Control of Ozone (O 3 ) and PM 2.5 in Atmosphere,” a material for presentationin the training for attendees visiting Japan “Monitoring techniques andmethodologies for ozone and PM 2.5 ” (documented by Mr. Hajime Mikasa,
Japan Environmental Technology Association (JETA))

8)MOEJ Environmental Management Bureau “Manual for Continuous
Monitoring of Air Pollution Sixth Edition” (March 2010)

9)

MOEJ “FY2010 Report on the State of Air Pollution” (February 2012)10)

MOEJ “FY2011 Report on the State of Air Pollution” (July 2013)11)

MOEJ “FY2012 Report on the State of Air Pollution” (July 2014)12)

MOEJ “FY2011 Report on the State of Air Pollution – Particulate Matter 2.5(PM 2.5 ) Component Measurement Results -” (July 2013)13)

MOEJ “FY2012 Report on the State of Air Pollution – Particulate Matter 2.5(PM 2.5 ) Component Measurement Results -” (July 2014)