ISO/TR 4227:1989

Planning of ambient air quality monitoring

Planification du contrôle de la qualité de l'air ambiant

Načrtovanje nadzorovalnega opazovanja (monitoringa) kakovosti okoljskega zraka

General Information

• Status: Withdrawn
• Publication Date: 08-Nov-1989
• Withdrawal Date: 08-Nov-1989
• ICS: 13.040.20 - Ambient atmospheres
• Technical Committee: ISO/TC 146/SC 4 - General aspects
• Drafting Committee: ISO/TC 146/SC 4/WG 2 - Uncertainty of air quality measurements
• Current Stage: 9599 - Withdrawal of International Standard
• Completion Date: 19-May-2000
• Ref Project: SIST ISO/TR 4227:1997 - Planning of ambient air quality monitoring

Standards Content (Sample)

TECHNICAL ISO
TR 4227
REPORT
First edition
1989-11-15
Planning of ambient air quality monitoring
Planifica tion du contrNe de Ia qualith de l’air ambiant
Reference number
ISO/TR 4227 : 1989 (EI

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ISO/TR 4227 : 1989 (EI
Contents
Page
. . .
Ill
Foreword .
iv
Introduction. .
1
1 Scope .
................................................. 1
2 Normative references
................................................ 1
3 General considerations
................................................. 1
4 Formulating the tasks
......................................... 1
4.1 Establishing the objectives
............................................... 2
4.2 Basic classification
3
4.3 Objec~ve .
..................................... 3
4.4 Data analysis and presentation
............................................... 5
4.5 Area of assessment
5
4.6 Period of Survey .
8
5 Measuringsystem .
8
6 Siting .
................................................... 8
6.1 Spatial aspects
9
6.2 Timeaspects .
................................................ 10
7 Additional information
.................................................... IO
7.1 Emission data
7.2 Transmission data . 10
................................................... 10
7.3 Immission data
IO
7.4 Effects .
10
8 Data processing .
............................................... 10
8.1 Data interpretation
10
8.2 Datasynthesis. .
........................... 11
9 Classification of ambient air quality monitoring
Annexes
........... 12
A Mathematical formulae for emission, transmission and immission
13
B Measuringsystem .
............. 14
C Matrix for designing a warning System and establishing trends
16
D Bibliography .
0 ISO 1989
All rights reserved. No part of this publication may be reproduced or utilized in any form or by any
means, electronie or mechanical, including photocopying and microfilm, without Permission in
writing from the publisher.
International Organization for Standardization
Case postale 56 l CH-1211 Geneve 20 l Switzerland
Printed in Switzerland
ii

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ISO/TR 4227 : 1989 El
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of
national Standards bodies (ISO member bodies). The work of preparing International
Standards is normally carried out through ISO technical committees. Esch member
body interested in a subject for which a technical committee has been established has
the right to be represented on that committee. International organizations, govern-
mental and non-governmental, in liaison with ISO, also take part in the work. ISO
collaborates closely with the International Electrotechnical Commission (IEC) on all
matters of electrotechnical standardization.
The main task of ISO technical committees is to prepare International Standards. In ex-
ceptional circumstances a technical committee may propose the publjcation of a
technical report of one of the following types:
1, whe n the necessary support within the technical committee ca nnot be
- tYPe
obtained for the publication of an International Standard, despite repeated eff Orts;
su bject is still under technical
2, when the development requiring wider
- tYPe
exposu re
-
type 3, when a technical committee has collected data of a different kind from
that which is normally published as an International Standard (“state of the art”, for
example).
Technical reports are accepted for publication directly by ISO Council. Technical
reports of types 1 and 2 are subject to review within three years of publication, to
decide whether they tan be transformed into International Standard. Technical reports,
of type 3 do not necessarily have to be reviewed until the data they provide are con-
sidered to be no longer valid or useful.
ISO/TR 4227, which is a technical report of type 2, was prepared by Technical Com-
mittee ISO/TC 146, Air quaky.
Annexes A, B and C form an integral part of this Technical Report.

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ISO/TR 4227 : 1989 (E)
Introduction
In Order to protect the environment, many different aspects of air quality have to be
examined. These may include obtaining information on the existing local, regional or
global air quality, forecasting the quality of air Iikely to be expected in the future, eva-
luating monitoring possibilities, or considering the complicated relationship within the
context of formation and drift of airborne pollution. In each country such tasks may be
formulated differently depending on its type of industry, and topographical or climatic
Situation. Accordingly every country has created a different type of ambient air monito-
ring System. The data obtained often cannot be compared directly. lt is for this reason
that some standardization has been undertaken (see ISO 7168) to establish a useful
international exchange of ambient air quality data. In this Technical Report a classifica-
tion which could be used as a basis for standardization of ambient air quality monito-
ring tasks is introduced.
Standardization of air quality monitoring is only reasonable and possible for those air
quality monitoring Systems which deal with equivalent tasks. Air quality monitoring
tasks are considered to be equivalent if they fall into one class of the classification
scheme which covers the task as weil as the major aspect of the actual measuring
scheme. Using these classifications, all likely air quality monitoring Systems are arran-
ged in the form of a matrix, where each column represents a particular task and each
row a specific aspect of the measuring scheme. This representation enables detailed
comparisons to be made of different aspects of air quality monitoring.
iv

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TECHNICAL REPORT ISO/TR 4227 : 1989 (EI
Planning of ambient air quality monitoring
Emission is the transfer of air pollution from the Source into
1 Scope
the free atmosphere.
This Technical Report establishes a classification scheme which
Immission is the transfer of air pollution from the free at-
should form a general basis for international standardization of
mosphere to a receptor such as a human being, plant or
ambient air quality monitoring and permits comparison be-
building. The summation of immission rate over an interval of
tween existing and planned ambient air quality monitoring
time gives the immission dose, the total air pollutant intake by
Systems. The results of such comparisons may be used as
the receptor.
guidelines for standardization.
The sites at which emission or immission take place are defined
by the enveloping surface of the Source or the receptor.
2 Normative references
Transmission describes collectively phenomena affecting the
The following Standards contain provisions which, through
air pollutants in the free atmosphere between the Source and
reference in this text, constitute provisions of this Technical
the receptor. These phenomena include all dynamic physical ef-
Report. At the time of publication, the editions indicated were
fects such as dilution of the pollutant with air, as well as any
valid. All Standards are subject to revision, and Parties to
physical or Chemical reactions that might occur.
agreements based on this Technical Report are encouraged to
investigate the possibility of applying the most recent editions
In Order to describe these concepts quantitatively, mass or
of the Standards listed below. Members of IEC and ISO main- other quantifiable property flux and their derivatives have to be
tain registers of currently valid International Standards. used. Units of measurement are given in ISO 4225. An illustra-
tion of emission, transmission and immission is given in
ISO 4225 : 1980, Air quality - General aspects - Vocabulaty.
figure 1. Detailed explanations of the mathematical concepts
are given in annex A.
ISO 4226 : 1980, Air quality - General aspects - Units of
measuremen t.
According to these definitions, immission is a mass or other
quantifiable property rate per unit interval of time, which
Performance characteristics and
ISO 6879 : 1983, Air quality -
should be measured,. if possible, at the receptor. Usually, it is
related concepts for air quality measuring methods.
necessary to know the immission to a number sf different
receptors and not tonfine measurements to just one receptor.
ISO 7168 : 1985, Air quality - Presen tation of ambient air
An air pollution Survey should be designed to measure the im-
quality data in alphanumerical form.
mission to receptors and the possible effects. One may in-
troduce a “virtual receptor” with unit surfaces and unit proper-
ISO 8601 : 1988, Data elements and interchange formats -
ties and study, for each such receptor, the possible immission
Representation of dates and times.
Information in terchange -
as a function of space and time. A virtual receptor might be
S tra tified sampling me thod for
ISO 9359 : 1989, Air quality - simulated by a special measuring System or have a defined cor-
assessment of ambient air quality.
relation with a ground-level concentration or deposition.
4 Formulating the tasks
3 General considerations
All ambient air quality monitoring tasks are designed for the 4.1 Establishing the objectives
assessment of environmental effects. lt is therefore not suf-
Before starting measurements it is essential to establish what
ficient merely to measure air pollutants. lt is also necessary to
Problem has to be solved and what constraints may have to be
relate the results of these measurements to observed effects.
imposed on an “ideal” measuring System.
On the other hand, it is weil-known that the ground-level con-
centration of an air pollutant tan be correlated with emission
The following is a summary of questions to be considered.
rates and propagation conditions. This means that there exists
a causa1 relationship between the Source, the propagation and
a) Has the basic Problem been defined?
the effects of the air pollution.
1) Is there an air pollution Problem or a potential pro-
In Order to quantify any relationship, three basic concepts are
blem?
introduced : emission, transmission and immission. These con-
cepts are generally explained as follows (see also ISO 4225). 2) Does a need exist for a monitoring System?
1

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ISO/TR 4227 : 1989 (E)
Transmission - Immission
Emission -
Reaction
B - C+D
\
Wash-out
AT
t
/
Ah
- ~~
\
t AU
IeDosition
\
Ah
I
io’ I 1 ‘\
Source
Illustration explaining the concepts emission, transmission and immission
Figure 1 -
10) To provide data for interjurisdictional information
3) What should be the scope and limitations for
exchange?
monitoring?
11) To interface with other monitoring Systems?
b) To what extent does the basic Problem relate to the
following monitoring functions?
What are the economic and technical constraints?
c)
1) To quantify ambient air quality and its Variation in
space and time? 1) What funding is available and how does this relate
to the confidence in the ambient air quality data to be
2) To provide a basis for air pollution control regula-
obtained?
tion?
2) What restrictions exist on procurement?
3) To provide data for an integrated monitoring
System?
3) What are the manpower requirements for Operation,
maintenance, repair, calibration and ambient air quality
4) To determine the effectiveness of control action on
data evaluation?
ambient air quality?
4) What are the staff capabilities?
5) To provide real-time data for an alert and warning
system?
5) What are the training requirements for staff?
6) To determine source-receptor relations?
6) Is a realistic timetable achievable?
7) To analyse local circulation characteristics and ef-
Basic classification
2
fects?
Once the objective of the monitoring has been established, the
8) To provide trends for zoning and urban planning re-
task has to be formulated. In Order to do this, it is first of all
quirements?
essential to answer a number of questions concerning the ob-
jectives of the Survey, the area over which air quality is to be
9) To provide input data for operational urban models?

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ISO/TR 4227 : 1989 (El
period of the Survey and the way in which the examples are the establishment of ground- concentrations
assessed, the
at particular wind directions, etc.
data obtained are to be analysed and presented.
The following classification is suggested.
4.3.2 Diagnosis
a) Objective
Diagnosis is finding the reason why particular immission situa-
1 . . . Determination of facts
tions exist. Examples are: particular immissions due to special
conditions of emission or transmission, establishment of the
2. . Diagnosis
precise location of a Source, assessment of air pollutants to
specific Source or sources, establishment of the contribution of
3. *. Prediction
a Source to a definite immission Situation.
Data analysis and presentation
b)
To accomplish tasks such as these, measurements of ground-
level concentrations of air pollutants only maynot be enough.
. 1 . . Tabulation
Additional measurements may have to be made or information
Frequency distribution
. 2. obtained on emission, transmission and possible effects so that
correlations tan be made. This will be for identification of
Characteristic values
. 3.
sources following complaints, analysis of situations under
Stagnation conditions,
and determination of the relative
Cl Area of assessment
amount of air pollution attributable to space heating, traffit or
other sources in special situations.
. . 1 . Point assessment
. . 2. Unresolved area
4.3.3 Prediction
. . 3. Resolved area
Prediction should give information about immissions expected
d) Period of Survey in the future. These could be long-term predictions based on
climatic data or information on expected changes in emission
. . . 1 Individual air samples
or transmission, or short-term predictions for special conditions
of transmission, e.g. Stagnation conditions, wind direction and
. * . 2 Unresolved time
wind Speed, Chemical reactions, special emission conditions.
. . . 3 Resolved time
Typical examples are the long-term trend of immissions due to
increased industrial production, effects of planned abatement
The tasks do not have to be carried out in the Order in which
measures or immissions resulting from accidental emissions.
these classes are listed. The numbering serves as an identifica-
tion of the questions and the corresponding measuring
scheme. Thus each air quality monitoring task is given a four-
4.4
Data analysis and presentation
digit identification.
Data analysis and presentation shall be closely related to the
Details of this classification are given in 4.3 to 4.6.
objective of the Survey. lt shall yield sufficient information for
the solution of the Problem. For example, the following infor-
4.3 Objective
mation may be required:
Essentially the objective may be broken down into one of the
daily means of the concentrations of all air pollutants;
a)
three classes : determination of facts, diagnosis, prediction.
The amount of data needed to solve the Problem increases with
b) diurnal variations in the concentrations of all air
each class. For example, a diagnosis presupposes that the facts
pollutants;
have been determined and a prediction normally means that the
facts have already been stated and a diagnosis made.
nterval of time, which
c) i each day, during certain values
have been exceeded ( percentiles);
In most cases, measurements have to be made to solve the pro-
blem. This means that there will be uncertainties in the data
d) means of concentrations of air pollutants at certain
collected due to experimental error, unknown transmission
sampling sites when the wind is blowing from certain major
Parameters, etc. Consequently this leads to measurement
sou rces;
uncertainties which tan be quantified using statistical methods.
Thus in defining the objective it is mandatory to define also the
frequency distribution;
e)
minimum significance level (or measurement uncertainty)
allowable for the Problem to be solved.
hourly, daily, monthly maximum vahes;
fl
4.3.1 Determination of facts multiple regression analysis.
9)
This is to be understood as the Statement and documentation Care shall be taken that analysis and presentation of data for
of emission, transmission or immission situ ations. Typical
specific correlations do not lead to a loss of information that
3

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ISO/TR 4227 : 1989 (El
These dependencies are generally of a stochastic nature.
may be required at a later time. For example, the immision
Situation is completely described by a function of time and the Typical examples of this type of presentation are:
three-dimensional space vector in the area of assessment.
-
tables of measured values according to the co-
ordinates of different measurement Points for different in-
The measured space-time function could be presented either
for each sampling site as a function of time, or at a certain time tervals of time or special transmission conditions;
as a function of the sampling sites. Usually the questions are far
-
tables of measured values for selected measurement
more complex and involve the dependence of the immission on
Points in chronological Order.
certain emission and transmission Parameters. These
Parameters are also space-time functions; therefore the re-
quired relationsips may be derived if these and the immision are
4.4.2 Frequency distribution
given as a function of time and space. On the other hand, the
immission tan be presented as a function of the Parameters
Frequency distribution describes the relationship between the
themselves. Where this is done, information about time and
values of a characteristic and their absolute or relative fre-
space will be lost. For example, the dependence of immission
quency of occurrence. This frequency may be presented as ac-
on wind direction is derived simply from the two functions: im-
tual, relative or cumulative and tan be depicted as a table, a
mission as a function of time and wind direction as a function
graphic (see figure 2) or as coefficients of a function. A typical
of time. However, if the data are reduced in such a way, the in-
example is the relative frequencies of the occurrence of
formation on time is lost, and the time relationship of the im-
measured values within defined limits of concentration for
mission cannot be recovered if additional investigations of the
every measurement Point in an area of assessment during the
effect of other Parameters become necessary. These aspects
specif ied period .
shall therefore be considered carefully in setting up measuring
schemes and equipment.
lt should be noted that this method of data reduction usually
brings about a loss of original information, since individual
The data presentation tan be done in three different ways as
identification of each measured value is lost in the process of
described in 4.4.1 to 4.4.3.
calculating statistical summaries.
4.4.1 Tabulation
4.4.3 Characteristic values
This is the presentation of data in the form of lists, such as
In many cases, the results may be depicted by a few
measured values of immission or its Substitute according to
characteristic values, e.g. the mean estimate of the indicated
location, time, or other Parameters relevant to the question.
percentile indices. These may be derived from the frequency
Tabulation gives the largest sets of data for general evaluation
distribution, computed from the original list, or obtained
at minimal expense.
directly during the measurement by means of automatic evalua-
tion. Data presentation by characteristic values gives the
Often these tables are a presentation of different dependencies,
highest degree of data reduction with a corresponding loss of
e.g. the dependence of immission on emission or transmission.
original information.
80
-
-
-
60
-
20
10
10
0
Ground-level concentration Ground-level concentration
Ground-level concentration
Examples of graphic presentation of distribution
Figure 2 -
4

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ISO/TR 4227 : 1989 El
4.5.3 Resolved area
4.5 Area of assessment
In most cases it is necessary to assess the immission with Within the area of assessment the immission should be assessed
regard to a number of different possible receptors and not for a as a function of space. This means that a certain spatial resolu-
special Single receptor localized at a certain Point. For this
tion has to be established during the formulation of the Problem
reason, the concept of virtual receptors is used. For a study of (see figure 3). The power of the spatial resolution is given by the
ground-level concentrations, the surface of a virtual receptor sampling site density, the accuracy of measurements, and pos-
might be placed at a certain height above ground level, whereas
sible additional information with regard to the spatial distribution
in a study of corrosion of buildings, a surface in the form of the of the immission. If evaluation is necessary within a limited inter-
building might be Chosen. The measuring Systems should be
val of time, the spatial resolution also depends on the variance of
placed to give representative values for the whole surface. the Object to be measured and therefore on the frequency of
measurements. Examples are the determination of Iines of equal
The area of assessment may be described by fixed or movable
average concentration where a certain limiting value is exceeded
co-ordinates and it may consist of one area or a number of dif-
within the area of assessment, or the determination of the
ferent sub-areas. For example, the measurement task is com-
decrease of concentrations of carbon monoxide. as a function of
pletely defined with regard to the area if a limitation or a defini-
increasing distance from a major roadway when the wind blows
tion tan be fixed according to
in a particular direction, the knowledge of the emission distribu-
tion serving as additional information.
-
geographical criteria or borders between countries;
-
sources or special groups of sources;
4.6 Period of Survey
-
special transmission conditions or special objects to be
The period of Survey may consist of one or a number of different
protected.
sections on a time axis. In each section, the immissions may be
assessed as a mean with regard to time or to time lapse.
For practical reasons it is best to have three classes of areas of
assessment, i.e. Point assessment, unresolved area and re-
Because of variations in emission and transmission conditions
solved area (see figure 3). In all three cases sampling sites are
during different intervals of time (year, week, day) as well as ir-
Chosen differently. If the area of assessment is composed of
regular cycles of emission and transmission, the period of Survey
one or a number of fixed Points, the sampling sites are directly
has to be defined very carefully. This is especially true if different
given by the formulation of the Problem. If the area of assess-
cycles occurring at the same intervals of time are to be con-
ment is composed of one or a number of areas which have to
sidered, e.g. overlapping of morning cycles of space heating with
be assessed without any spatial resolution, the measurement
daily traff ic density.
may be done by random sampling. Number and distribution of
the sampling sites are given by the variance of the Object to be
Differentiation into fixed individual sampling, unresolved time or
measured and the required accuracy. lf an area has to be
resolved time is therefore proposed for practical reasons. Fixed
assessed using the spatial dependence of the immission, the
individual sampling means that the interval of time of sampling is
number and distribution of the sampling sites also depend on
established by the formulation of the task. Unresolved time im-
the required spatial resolution.
plies that means are mainly to be considered. Here the number of
air samples and the interval of time of sampling depend only on
4.5.1 Point assessment
the variance of the Object to be measured and the required ac-
curacy. Resolved time implies that the time lapse of immission
The area of assesment may consist of one or a number of spatial-
has to be measured. In this case, the number of air samples
ly unconnected Points of assessment. A Point of assessment is
depends on the required time resolution and the reproducibility
defined as a small continuous area in which further sub-division
of the measuring System.
is neither possible nor necessary for an assessment of immission.
The Point of assessment is represented by the measuring System
used. Isolated Points of assessment tan be stationary or 4.6.1 Individual air samples
movable, e.g. a person or a Point 5 km downwind of a Source.
For individual sampling, one or a number of air samples are taken
An example of a number of unconnected Points combined into
over a specified period. The statt time at the beginning of the
one area of assessment is a playground (see figure 3).
period and the length of it will be defined by the formulation of
the task. The period sf Survey covers the intervals of time of
4.5.2 Unresolved area
sampling (see figure 4) and these may be on a Single occasion
An unresolved area of assessment tan be composed of one or a only, on cycles of occasions or at the intervals of time of special
number of areas. Where the immission for each area as a whole
situations.
is of interest and more than one sampling site for each area is
Examples are
required, spatial resolution is unnecessary (see figure 3) - for
example, the determination of the mean of concentrations of
-
the concentration of carbon monoxide at 08 : 25 hours
Sulfur dioxide in an industrial area where there may be more than
on 25 June 1973 [1973-06-25TO8 : 251)l;
one sampling site and where a spatial resolution regarding immis-
sion is not required between sampling sites. Another example of
-
the state of immission at sunrise each day during Winter;
the assessment of a number of sub-areas is the determination of
-
the 75 % percentiles of the concentrations of Sulfur dioxide in in- the sta te of immission at the beginning of break-up of an
dustrial, residential and recreational areas of a City. inversion.
Representation according to ISO 8601.
1)
5

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ISO/TR 4227 : 1989 (E)
Point assessment
The area of assessment is
composed of f ixed
Points of assessment, e.g.
playgrounds
Co-Ordinate of Position
Unresolved areas
The area of assessment consists of three
A
sub-areas, identified by 1, II, Ill, where each
is characterized by an average value of the
5 .g
ground-level concentration
ix
zs
cal
2:
GE
I I
I
1
1
i
\ A
Al
1 II m
Co-Ordinate of Position
lkm
t-l
Resolved areas
The spatial dependence of the ground-level
concentration is to be assessed (spatial
resolution: 1 km)
Co-Ordinate of Position
Figure 3 - Area of assessment and spatial resolution
6

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ISO/TR 4227 : 1989 (EI
Examples are
4.6.2 Unresolved time
-
means of the immission between 0 hour on 13 June
The period of Survey may consist of one or a number of
1973 (1973-06-13TOO : 00) and 0 hour on 14 June 1973
intervals of time during which the immission is evaluated in-
(1973-06-14TOO : 00);
dependently of time and where the number of air samples per
-
means over one year;
interval of time depends on the variance of the Object being
measured. No time resolution of the quantity in the interval of
-
means over each of the four seasons of the year;
time is needed. Again, there may be Single occasions, cycles of
- 90 % value for rush-hour or heating period;
occasions or special situations (see figure 4).
-
means of immission dose during inversion.
Individual air samples
The year is assessed by
instantaneous air samples given by
the special Situation of inversion
brea k-up
Month
12
Co-Ordinate of time
Unresolved time
The year is assessed using monthly
means, in sequence
1 2 3 4 5 6 7 8 9 10 11
12 Month
Co-Ordinate of time
Resolved time
The year is assessed using a time
lapse with a time resolution of one
daY
1
2 3 4 5 6 7 6 9 10 11 12 Month
Co-Ordinate of time
Period of Survey and time resoltition
Figure 4 -
7

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ISO/TR 4227 : 1989 EI
4.6.3 Resolved time 6.1 Spatial aspects
Here, the period of Survey covers one or a number of intervals
6.1 .l Continuous
of time du
...

SLOVENSKI STANDARD
SIST ISO/TR 4227:1997
01-avgust-1997
1DþUWRYDQMHQDG]RURYDOQHJDRSD]RYDQMDPRQLWRULQJDNDNRYRVWLRNROMVNHJD]UDND
Planning of ambient air quality monitoring
Planification du contrôle de la qualité de l'air ambiant
Ta slovenski standard je istoveten z: ISO/TR 4227:1989
ICS:
13.040.20 Kakovost okoljskega zraka Ambient atmospheres
SIST ISO/TR 4227:1997 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST ISO/TR 4227:1997

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SIST ISO/TR 4227:1997
TECHNICAL ISO
TR 4227
REPORT
First edition
1989-11-15
Planning of ambient air quality monitoring
Planifica tion du contrNe de Ia qualith de l’air ambiant
Reference number
ISO/TR 4227 : 1989 (EI

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SIST ISO/TR 4227:1997
ISO/TR 4227 : 1989 (EI
Contents
Page
. . .
Ill
Foreword .
iv
Introduction. .
1
1 Scope .
................................................. 1
2 Normative references
................................................ 1
3 General considerations
................................................. 1
4 Formulating the tasks
......................................... 1
4.1 Establishing the objectives
............................................... 2
4.2 Basic classification
3
4.3 Objec~ve .
..................................... 3
4.4 Data analysis and presentation
............................................... 5
4.5 Area of assessment
5
4.6 Period of Survey .
8
5 Measuringsystem .
8
6 Siting .
................................................... 8
6.1 Spatial aspects
9
6.2 Timeaspects .
................................................ 10
7 Additional information
.................................................... IO
7.1 Emission data
7.2 Transmission data . 10
................................................... 10
7.3 Immission data
IO
7.4 Effects .
10
8 Data processing .
............................................... 10
8.1 Data interpretation
10
8.2 Datasynthesis. .
........................... 11
9 Classification of ambient air quality monitoring
Annexes
........... 12
A Mathematical formulae for emission, transmission and immission
13
B Measuringsystem .
............. 14
C Matrix for designing a warning System and establishing trends
16
D Bibliography .
0 ISO 1989
All rights reserved. No part of this publication may be reproduced or utilized in any form or by any
means, electronie or mechanical, including photocopying and microfilm, without Permission in
writing from the publisher.
International Organization for Standardization
Case postale 56 l CH-1211 Geneve 20 l Switzerland
Printed in Switzerland
ii

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SIST ISO/TR 4227:1997
ISO/TR 4227 : 1989 El
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of
national Standards bodies (ISO member bodies). The work of preparing International
Standards is normally carried out through ISO technical committees. Esch member
body interested in a subject for which a technical committee has been established has
the right to be represented on that committee. International organizations, govern-
mental and non-governmental, in liaison with ISO, also take part in the work. ISO
collaborates closely with the International Electrotechnical Commission (IEC) on all
matters of electrotechnical standardization.
The main task of ISO technical committees is to prepare International Standards. In ex-
ceptional circumstances a technical committee may propose the publjcation of a
technical report of one of the following types:
1, whe n the necessary support within the technical committee ca nnot be
- tYPe
obtained for the publication of an International Standard, despite repeated eff Orts;
su bject is still under technical
2, when the development requiring wider
- tYPe
exposu re
-
type 3, when a technical committee has collected data of a different kind from
that which is normally published as an International Standard (“state of the art”, for
example).
Technical reports are accepted for publication directly by ISO Council. Technical
reports of types 1 and 2 are subject to review within three years of publication, to
decide whether they tan be transformed into International Standard. Technical reports,
of type 3 do not necessarily have to be reviewed until the data they provide are con-
sidered to be no longer valid or useful.
ISO/TR 4227, which is a technical report of type 2, was prepared by Technical Com-
mittee ISO/TC 146, Air quaky.
Annexes A, B and C form an integral part of this Technical Report.

---------------------- Page: 5 ----------------------

SIST ISO/TR 4227:1997
ISO/TR 4227 : 1989 (E)
Introduction
In Order to protect the environment, many different aspects of air quality have to be
examined. These may include obtaining information on the existing local, regional or
global air quality, forecasting the quality of air Iikely to be expected in the future, eva-
luating monitoring possibilities, or considering the complicated relationship within the
context of formation and drift of airborne pollution. In each country such tasks may be
formulated differently depending on its type of industry, and topographical or climatic
Situation. Accordingly every country has created a different type of ambient air monito-
ring System. The data obtained often cannot be compared directly. lt is for this reason
that some standardization has been undertaken (see ISO 7168) to establish a useful
international exchange of ambient air quality data. In this Technical Report a classifica-
tion which could be used as a basis for standardization of ambient air quality monito-
ring tasks is introduced.
Standardization of air quality monitoring is only reasonable and possible for those air
quality monitoring Systems which deal with equivalent tasks. Air quality monitoring
tasks are considered to be equivalent if they fall into one class of the classification
scheme which covers the task as weil as the major aspect of the actual measuring
scheme. Using these classifications, all likely air quality monitoring Systems are arran-
ged in the form of a matrix, where each column represents a particular task and each
row a specific aspect of the measuring scheme. This representation enables detailed
comparisons to be made of different aspects of air quality monitoring.
iv

---------------------- Page: 6 ----------------------

SIST ISO/TR 4227:1997
TECHNICAL REPORT ISO/TR 4227 : 1989 (EI
Planning of ambient air quality monitoring
Emission is the transfer of air pollution from the Source into
1 Scope
the free atmosphere.
This Technical Report establishes a classification scheme which
Immission is the transfer of air pollution from the free at-
should form a general basis for international standardization of
mosphere to a receptor such as a human being, plant or
ambient air quality monitoring and permits comparison be-
building. The summation of immission rate over an interval of
tween existing and planned ambient air quality monitoring
time gives the immission dose, the total air pollutant intake by
Systems. The results of such comparisons may be used as
the receptor.
guidelines for standardization.
The sites at which emission or immission take place are defined
by the enveloping surface of the Source or the receptor.
2 Normative references
Transmission describes collectively phenomena affecting the
The following Standards contain provisions which, through
air pollutants in the free atmosphere between the Source and
reference in this text, constitute provisions of this Technical
the receptor. These phenomena include all dynamic physical ef-
Report. At the time of publication, the editions indicated were
fects such as dilution of the pollutant with air, as well as any
valid. All Standards are subject to revision, and Parties to
physical or Chemical reactions that might occur.
agreements based on this Technical Report are encouraged to
investigate the possibility of applying the most recent editions
In Order to describe these concepts quantitatively, mass or
of the Standards listed below. Members of IEC and ISO main- other quantifiable property flux and their derivatives have to be
tain registers of currently valid International Standards. used. Units of measurement are given in ISO 4225. An illustra-
tion of emission, transmission and immission is given in
ISO 4225 : 1980, Air quality - General aspects - Vocabulaty.
figure 1. Detailed explanations of the mathematical concepts
are given in annex A.
ISO 4226 : 1980, Air quality - General aspects - Units of
measuremen t.
According to these definitions, immission is a mass or other
quantifiable property rate per unit interval of time, which
Performance characteristics and
ISO 6879 : 1983, Air quality -
should be measured,. if possible, at the receptor. Usually, it is
related concepts for air quality measuring methods.
necessary to know the immission to a number sf different
receptors and not tonfine measurements to just one receptor.
ISO 7168 : 1985, Air quality - Presen tation of ambient air
An air pollution Survey should be designed to measure the im-
quality data in alphanumerical form.
mission to receptors and the possible effects. One may in-
troduce a “virtual receptor” with unit surfaces and unit proper-
ISO 8601 : 1988, Data elements and interchange formats -
ties and study, for each such receptor, the possible immission
Representation of dates and times.
Information in terchange -
as a function of space and time. A virtual receptor might be
S tra tified sampling me thod for
ISO 9359 : 1989, Air quality - simulated by a special measuring System or have a defined cor-
assessment of ambient air quality.
relation with a ground-level concentration or deposition.
4 Formulating the tasks
3 General considerations
All ambient air quality monitoring tasks are designed for the 4.1 Establishing the objectives
assessment of environmental effects. lt is therefore not suf-
Before starting measurements it is essential to establish what
ficient merely to measure air pollutants. lt is also necessary to
Problem has to be solved and what constraints may have to be
relate the results of these measurements to observed effects.
imposed on an “ideal” measuring System.
On the other hand, it is weil-known that the ground-level con-
centration of an air pollutant tan be correlated with emission
The following is a summary of questions to be considered.
rates and propagation conditions. This means that there exists
a causa1 relationship between the Source, the propagation and
a) Has the basic Problem been defined?
the effects of the air pollution.
1) Is there an air pollution Problem or a potential pro-
In Order to quantify any relationship, three basic concepts are
blem?
introduced : emission, transmission and immission. These con-
cepts are generally explained as follows (see also ISO 4225). 2) Does a need exist for a monitoring System?
1

---------------------- Page: 7 ----------------------

SIST ISO/TR 4227:1997
ISO/TR 4227 : 1989 (E)
Transmission - Immission
Emission -
Reaction
B - C+D
\
Wash-out
AT
t
/
Ah
- ~~
\
t AU
IeDosition
\
Ah
I
io’ I 1 ‘\
Source
Illustration explaining the concepts emission, transmission and immission
Figure 1 -
10) To provide data for interjurisdictional information
3) What should be the scope and limitations for
exchange?
monitoring?
11) To interface with other monitoring Systems?
b) To what extent does the basic Problem relate to the
following monitoring functions?
What are the economic and technical constraints?
c)
1) To quantify ambient air quality and its Variation in
space and time? 1) What funding is available and how does this relate
to the confidence in the ambient air quality data to be
2) To provide a basis for air pollution control regula-
obtained?
tion?
2) What restrictions exist on procurement?
3) To provide data for an integrated monitoring
System?
3) What are the manpower requirements for Operation,
maintenance, repair, calibration and ambient air quality
4) To determine the effectiveness of control action on
data evaluation?
ambient air quality?
4) What are the staff capabilities?
5) To provide real-time data for an alert and warning
system?
5) What are the training requirements for staff?
6) To determine source-receptor relations?
6) Is a realistic timetable achievable?
7) To analyse local circulation characteristics and ef-
Basic classification
2
fects?
Once the objective of the monitoring has been established, the
8) To provide trends for zoning and urban planning re-
task has to be formulated. In Order to do this, it is first of all
quirements?
essential to answer a number of questions concerning the ob-
jectives of the Survey, the area over which air quality is to be
9) To provide input data for operational urban models?

---------------------- Page: 8 ----------------------

SIST ISO/TR 4227:1997
ISO/TR 4227 : 1989 (El
period of the Survey and the way in which the examples are the establishment of ground- concentrations
assessed, the
at particular wind directions, etc.
data obtained are to be analysed and presented.
The following classification is suggested.
4.3.2 Diagnosis
a) Objective
Diagnosis is finding the reason why particular immission situa-
1 . . . Determination of facts
tions exist. Examples are: particular immissions due to special
conditions of emission or transmission, establishment of the
2. . Diagnosis
precise location of a Source, assessment of air pollutants to
specific Source or sources, establishment of the contribution of
3. *. Prediction
a Source to a definite immission Situation.
Data analysis and presentation
b)
To accomplish tasks such as these, measurements of ground-
level concentrations of air pollutants only maynot be enough.
. 1 . . Tabulation
Additional measurements may have to be made or information
Frequency distribution
. 2. obtained on emission, transmission and possible effects so that
correlations tan be made. This will be for identification of
Characteristic values
. 3.
sources following complaints, analysis of situations under
Stagnation conditions,
and determination of the relative
Cl Area of assessment
amount of air pollution attributable to space heating, traffit or
other sources in special situations.
. . 1 . Point assessment
. . 2. Unresolved area
4.3.3 Prediction
. . 3. Resolved area
Prediction should give information about immissions expected
d) Period of Survey in the future. These could be long-term predictions based on
climatic data or information on expected changes in emission
. . . 1 Individual air samples
or transmission, or short-term predictions for special conditions
of transmission, e.g. Stagnation conditions, wind direction and
. * . 2 Unresolved time
wind Speed, Chemical reactions, special emission conditions.
. . . 3 Resolved time
Typical examples are the long-term trend of immissions due to
increased industrial production, effects of planned abatement
The tasks do not have to be carried out in the Order in which
measures or immissions resulting from accidental emissions.
these classes are listed. The numbering serves as an identifica-
tion of the questions and the corresponding measuring
scheme. Thus each air quality monitoring task is given a four-
4.4
Data analysis and presentation
digit identification.
Data analysis and presentation shall be closely related to the
Details of this classification are given in 4.3 to 4.6.
objective of the Survey. lt shall yield sufficient information for
the solution of the Problem. For example, the following infor-
4.3 Objective
mation may be required:
Essentially the objective may be broken down into one of the
daily means of the concentrations of all air pollutants;
a)
three classes : determination of facts, diagnosis, prediction.
The amount of data needed to solve the Problem increases with
b) diurnal variations in the concentrations of all air
each class. For example, a diagnosis presupposes that the facts
pollutants;
have been determined and a prediction normally means that the
facts have already been stated and a diagnosis made.
nterval of time, which
c) i each day, during certain values
have been exceeded ( percentiles);
In most cases, measurements have to be made to solve the pro-
blem. This means that there will be uncertainties in the data
d) means of concentrations of air pollutants at certain
collected due to experimental error, unknown transmission
sampling sites when the wind is blowing from certain major
Parameters, etc. Consequently this leads to measurement
sou rces;
uncertainties which tan be quantified using statistical methods.
Thus in defining the objective it is mandatory to define also the
frequency distribution;
e)
minimum significance level (or measurement uncertainty)
allowable for the Problem to be solved.
hourly, daily, monthly maximum vahes;
fl
4.3.1 Determination of facts multiple regression analysis.
9)
This is to be understood as the Statement and documentation Care shall be taken that analysis and presentation of data for
of emission, transmission or immission situ ations. Typical
specific correlations do not lead to a loss of information that
3

---------------------- Page: 9 ----------------------

SIST ISO/TR 4227:1997
ISO/TR 4227 : 1989 (El
These dependencies are generally of a stochastic nature.
may be required at a later time. For example, the immision
Situation is completely described by a function of time and the Typical examples of this type of presentation are:
three-dimensional space vector in the area of assessment.
-
tables of measured values according to the co-
ordinates of different measurement Points for different in-
The measured space-time function could be presented either
for each sampling site as a function of time, or at a certain time tervals of time or special transmission conditions;
as a function of the sampling sites. Usually the questions are far
-
tables of measured values for selected measurement
more complex and involve the dependence of the immission on
Points in chronological Order.
certain emission and transmission Parameters. These
Parameters are also space-time functions; therefore the re-
quired relationsips may be derived if these and the immision are
4.4.2 Frequency distribution
given as a function of time and space. On the other hand, the
immission tan be presented as a function of the Parameters
Frequency distribution describes the relationship between the
themselves. Where this is done, information about time and
values of a characteristic and their absolute or relative fre-
space will be lost. For example, the dependence of immission
quency of occurrence. This frequency may be presented as ac-
on wind direction is derived simply from the two functions: im-
tual, relative or cumulative and tan be depicted as a table, a
mission as a function of time and wind direction as a function
graphic (see figure 2) or as coefficients of a function. A typical
of time. However, if the data are reduced in such a way, the in-
example is the relative frequencies of the occurrence of
formation on time is lost, and the time relationship of the im-
measured values within defined limits of concentration for
mission cannot be recovered if additional investigations of the
every measurement Point in an area of assessment during the
effect of other Parameters become necessary. These aspects
specif ied period .
shall therefore be considered carefully in setting up measuring
schemes and equipment.
lt should be noted that this method of data reduction usually
brings about a loss of original information, since individual
The data presentation tan be done in three different ways as
identification of each measured value is lost in the process of
described in 4.4.1 to 4.4.3.
calculating statistical summaries.
4.4.1 Tabulation
4.4.3 Characteristic values
This is the presentation of data in the form of lists, such as
In many cases, the results may be depicted by a few
measured values of immission or its Substitute according to
characteristic values, e.g. the mean estimate of the indicated
location, time, or other Parameters relevant to the question.
percentile indices. These may be derived from the frequency
Tabulation gives the largest sets of data for general evaluation
distribution, computed from the original list, or obtained
at minimal expense.
directly during the measurement by means of automatic evalua-
tion. Data presentation by characteristic values gives the
Often these tables are a presentation of different dependencies,
highest degree of data reduction with a corresponding loss of
e.g. the dependence of immission on emission or transmission.
original information.
80
-
-
-
60
-
20
10
10
0
Ground-level concentration Ground-level concentration
Ground-level concentration
Examples of graphic presentation of distribution
Figure 2 -
4

---------------------- Page: 10 ----------------------

SIST ISO/TR 4227:1997
ISO/TR 4227 : 1989 El
4.5.3 Resolved area
4.5 Area of assessment
In most cases it is necessary to assess the immission with Within the area of assessment the immission should be assessed
regard to a number of different possible receptors and not for a as a function of space. This means that a certain spatial resolu-
special Single receptor localized at a certain Point. For this
tion has to be established during the formulation of the Problem
reason, the concept of virtual receptors is used. For a study of (see figure 3). The power of the spatial resolution is given by the
ground-level concentrations, the surface of a virtual receptor sampling site density, the accuracy of measurements, and pos-
might be placed at a certain height above ground level, whereas
sible additional information with regard to the spatial distribution
in a study of corrosion of buildings, a surface in the form of the of the immission. If evaluation is necessary within a limited inter-
building might be Chosen. The measuring Systems should be
val of time, the spatial resolution also depends on the variance of
placed to give representative values for the whole surface. the Object to be measured and therefore on the frequency of
measurements. Examples are the determination of Iines of equal
The area of assessment may be described by fixed or movable
average concentration where a certain limiting value is exceeded
co-ordinates and it may consist of one area or a number of dif-
within the area of assessment, or the determination of the
ferent sub-areas. For example, the measurement task is com-
decrease of concentrations of carbon monoxide. as a function of
pletely defined with regard to the area if a limitation or a defini-
increasing distance from a major roadway when the wind blows
tion tan be fixed according to
in a particular direction, the knowledge of the emission distribu-
tion serving as additional information.
-
geographical criteria or borders between countries;
-
sources or special groups of sources;
4.6 Period of Survey
-
special transmission conditions or special objects to be
The period of Survey may consist of one or a number of different
protected.
sections on a time axis. In each section, the immissions may be
assessed as a mean with regard to time or to time lapse.
For practical reasons it is best to have three classes of areas of
assessment, i.e. Point assessment, unresolved area and re-
Because of variations in emission and transmission conditions
solved area (see figure 3). In all three cases sampling sites are
during different intervals of time (year, week, day) as well as ir-
Chosen differently. If the area of assessment is composed of
regular cycles of emission and transmission, the period of Survey
one or a number of fixed Points, the sampling sites are directly
has to be defined very carefully. This is especially true if different
given by the formulation of the Problem. If the area of assess-
cycles occurring at the same intervals of time are to be con-
ment is composed of one or a number of areas which have to
sidered, e.g. overlapping of morning cycles of space heating with
be assessed without any spatial resolution, the measurement
daily traff ic density.
may be done by random sampling. Number and distribution of
the sampling sites are given by the variance of the Object to be
Differentiation into fixed individual sampling, unresolved time or
measured and the required accuracy. lf an area has to be
resolved time is therefore proposed for practical reasons. Fixed
assessed using the spatial dependence of the immission, the
individual sampling means that the interval of time of sampling is
number and distribution of the sampling sites also depend on
established by the formulation of the task. Unresolved time im-
the required spatial resolution.
plies that means are mainly to be considered. Here the number of
air samples and the interval of time of sampling depend only on
4.5.1 Point assessment
the variance of the Object to be measured and the required ac-
curacy. Resolved time implies that the time lapse of immission
The area of assesment may consist of one or a number of spatial-
has to be measured. In this case, the number of air samples
ly unconnected Points of assessment. A Point of assessment is
depends on the required time resolution and the reproducibility
defined as a small continuous area in which further sub-division
of the measuring System.
is neither possible nor necessary for an assessment of immission.
The Point of assessment is represented by the measuring System
used. Isolated Points of assessment tan be stationary or 4.6.1 Individual air samples
movable, e.g. a person or a Point 5 km downwind of a Source.
For individual sampling, one or a number of air samples are taken
An example of a number of unconnected Points combined into
over a specified period. The statt time at the beginning of the
one area of assessment is a playground (see figure 3).
period and the length of it will be defined by the formulation of
the task. The period sf Survey covers the intervals of time of
4.5.2 Unresolved area
sampling (see figure 4) and these may be on a Single occasion
An unresolved area of assessment tan be composed of one or a only, on cycles of occasions or at the intervals of time of special
number of areas. Where the immission for each area as a whole
situations.
is of interest and more than one sampling site for each area is
Examples are
required, spatial resolution is unnecessary (see figure 3) - for
example, the determination of the mean of concentrations of
-
the concentration of carbon monoxide at 08 : 25 hours
Sulfur dioxide in an industrial area where there may be more than
on 25 June 1973 [1973-06-25TO8 : 251)l;
one sampling site and where a spatial resolution regarding immis-
sion is not required between sampling sites. Another example of
-
the state of immission at sunrise each day during Winter;
the assessment of a number of sub-areas is the determination of
-
the 75 % percentiles of the concentrations of Sulfur dioxide in in- the sta te of immission at the beginning of break-up of an
dustrial, residential and recreational areas of a City. inversion.
Representation according to ISO 8601.
1)
5

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SIST ISO/TR 4227:1997
ISO/TR 4227 : 1989 (E)
Point assessment
The area of assessment is
composed of f ixed
Points of assessment, e.g.
playgrounds
Co-Ordinate of Position
Unresolved areas
The area of assessment consists of three
A
sub-areas, identified by 1, II, Ill, where each
is characterized by an average value of the
5 .g
ground-level concentration
ix
zs
cal
2:
GE
I I
I
1
1
i
\ A
Al
1 II m
Co-Ordinate of Position
lkm
t-l
Resolved areas
The spatial dependence of the ground-level
concentration is to be assessed (spatial
resolution: 1 km)
Co-Ordinate of Position
Figure 3 - Area of assessment and spatial resolution
6

---------------------- Page: 12 ----------------------

SIST ISO/TR 4227:1997
ISO/TR 4227 : 1989 (EI
Examples are
4.6.2 Unresolved time
-
means of the immission between 0 hour on 13 June
The period of Survey may consist of one or a number of
1973 (1973-06-13TOO : 00) and 0 hour on 14 June 1973
intervals of time during which the immission is evaluated in-
(1973-06-14TOO : 00);
dependently of time and where the number of air samples per
-
means over one year;
interval of time depends on the variance of the Object being
measured. No time resolution of the quantity in the interval of
-
means over each of the four seasons of the year;
time is needed. Again, ther
...

RAPPORT
IS0
TECHNIQUE TR 4227
Première édition
1989-1 1-15
Planification du contrôle de la qualité de l'air
ambiant
Planning of ambient air quality monitoring
Numéro de référence
ISO/TR 4227 : 1989 (FI

---------------------- Page: 1 ----------------------
ISO/TR 4227 : 1989 (FI
Sommaire
Page
...........................................................
Avant.propos iii
Introduction . iv
1 Domaine d'application .
1
2 Références normatives .
1
3 Considérations générales .
1
4 Formulationdestâches . 2
4.1 Fixation des objectifs .
2
4.2 Classement par catégories fondamentales . 3
.........................................................
4.3 Objectif 3
Analyse et présentation des données . 4
4.4
4.5 Zone d'évaluation .
4
4.6 Durée d'observation de l'étude . 7
5 Systèmedemesurage .
7
6 Choixdesite . 9
6.1 Aspects relatifs à l'espace . 9
6.2 Aspects relatifs au temps .
10
7 Renseignements supplémentaires . .
11
Données relatives à l'émission .
7.1 . 11
7.2 Données relatives à la transmission .
11
7.3 Données relatives à I'immission . . 11
7.4 Conséquences . .
11
8 Traitement des données .
...... 11
8.1 Interprétation des données .
11
8.2 Synthèse des données .
11
9
Classification du contrôle de la qualité de l'air ambiant . 12
Annexes
Formules mathématiques relatives à l'émission. la transmission
A
....................................................... 13
et I'immission
B Instruments de mesure . 14
C Matrice pour la conception d'un système d'alerte et l'établissement
destendances . 15
D Bibliographie . 17
O IS0 1989
Droits de reproduction réservés . Aucune partie de cette publication ne peut être reproduite ni
utilisée sous quelque forme que ce soit et par aucun procédé. électronique ou mécanique.
y compris la photocopie et les microfilms. sans l'accord écrit de l'éditeur .
Organisation internationale de normalisation
Case postale 56 0 CH-1211 Genève 20 0 Suisse
Imprimé en Suisse
II

---------------------- Page: 2 ----------------------
ISO/TR 4227 : 1989 (FI
Avant-propos
L’ISO (Organisation internationale de normalisation) est une fédération mondiale
d’organismes nationaux de normalisation (comités membres de I’ISO). L’élaboration
des Normes internationales est en général confiée aux comités techniques de I’ISO.
Chaque comité membre intéressé par une étude a le droit de faire partie du comité
technique créé à cet effet. Les organisations internationales, gouvernementales et non
gouvernementales, en liaison avec I’ISO participent également aux travaux. L’ISO col-
labore étroitement avec la Commission électrotechnique internationale (CEI) en ce qui
concerne la normalisation électrotechnique.
La tâche principale des comités techniques de I’ISO est d’élaborer les Normes interna-
tionales. Exceptionnellement, un comité technique peut proposer la publication d‘un
rapport technique de l‘un des types suivants :
- type 1 : lorsque, en dépit de maints efforts au sein d‘un comité technique,
l’accord requis ne peut être réalisé en faveur de la publication d‘une Norme interna-
tionale;
-
type 2: lorsque le sujet en question est encore en cours de développement
technique et requiert une plus grande expérience;
- type 3 : lorsqu’un comité technique a réuni des données de nature différente
de celles qui sont normalement publiées comme Norme internationales (ceci pou-
vant comprendre des informations sur l’état de la technique, par exemple).
La publication des rapports techniques dépend directement de l’acceptation du Conseil
de I’ISO. Les rapports techniques des types 1 et 2 font l’objet d’un nouvel examen trois
ans au plus tard après leur publication afin de décider éventuellement de leur transfor-
3 ne doivent pas
mation en Normes internationales. Les rapports techniques du type
nécessairement être révisés avant que les données fournies ne soient plus jugées vala-
bles ou utiles.
L‘ISO/TR 4227, rapport technique du type 2, a été élaboré par le comité technique
ISO/TC 146, Qualité de l’air.
Les annexes A, B et C font partie intégrante du présent Rapport technique.
iii

---------------------- Page: 3 ----------------------
ISO/TR 4227 : 1989 (FI
Introduction
Afin de protéger l’environnement, on doit examiner beaucoup d’aspects différents de
la qualité de l‘air. Parmi ceux-ci, on peut citer l’obtention d’informations sur la qualité
locale, régionale ou globale de l‘air, la prévision de la qualité probable de l‘air dans
l’avenir, l’évaluation des possibilités de contrôle ou l’examen des relations complexes
existant entre la formation et la dérive de la pollution en suspension dans l‘air. En outre,
selon les pays, ces tâches peuvent être formulées de facon différente suivant les critè-
res industriels et topographiques ou climatiques. Par conséquent, chaque pays a créé
un type différent de système de contrôle de la qualité de l‘air ambiant. On constate sou-
vent que les résultats obtenus ne peuvent pas être comparés directement. C’est pour
cette raison qu’un certaine normalisation a été entreprise (voir IS0 7168) afin d’établir
un échange international fructueux dans le domaine des données relatives à la qualité
de l’air ambiant. Dans le présent Rapport technique est introduite une classification
susceptible d’être utilisée comme base pour la normalisation des tâches de contrôle de
la qualité de l’air ambiant. La normalisation n’est raisonnable et possible que pour les
systèmes de contrôle de la qualité de l’air traitant de problèmes équivalents. On consi-
dère les tâches de contrôle de la qualité de l‘air comme étant équivalentes, si elles tom-
bent dans une catégorie du schéma de classification qui englobe la tâche, de même
que l’aspect principal du véritable schéma de mesure. En employant ces classifications,
toutes les méthodes de mesures possibles sont disposées sous forme d’une matrice,
dans laquelle chaque colonne verticale représente un problème particulier et chaque
ligne horizontale représente une caractéristique spécifique de la méthode de mesure.
Grâce à la matrice, il est possible d’établir des comparaisons détaillées entre différents
aspects des méthodes de contrôle de la qualité de l’air.
iv

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ISO/TR 4227 : 1989 (FI
RAPPORT TECHNIQUE
Planification du contrôle de la qualité de l'air ambiant
constatés. Par ailleurs, il est bien connu que la concentration
1 Domaine d'application
d'un polluant atmosphérique au niveau du sol peut être en cor-
Le présent Rapport technique établit un schéma de classifica- rélation avec les débits d'émission et avec ses conditions de
tion devant constituer une base générale pour la normalisation propagation, ce qui signifie qu'il y a une relation de cause à
internationale du contrôle de la qualité de l'air ambiant et qui effet entre la source, la propagation et les effets de la polution
permet la comparaison des méthodes de contrôle de la qualité atmosphérique.
de l'air ambiant existantes et en cours d'élaboration. Les résul-
Pour quantifier cette notion, on utilise trois concepts fonda-
tats de ces comparaisons peuvent servir de directives en vue
mentaux : l'émission, la transmission et I'immission. Ces con-
d'établir une normalisation.
cepts sont expliqués d'une façon générale ci-après (voir aussi
a
IS0 4225).
2 Références normatives
L'émission est le transfert de la pollution atmosphérique de la
source à l'atmosphère libre.
Les normes suivantes contiennent des dispositions qui, par
suite de la référence qui en est faite, constituent des disposi-
L'immission est le transfert de la pollution atmosphérique de
tions valables pour le présent Rapport technique. Au moment
l'atmosphère libre à un récepteur tel qu'un être humain, une
de la publication, les éditions indiquées étaient en vigueur.
plante ou un immeuble. La sommation du débit de I'immission
Toute norme est sujette à révision et les parties prenantes des
sur une période de temps donne la dose d'immission, c'est-à-dire
accords fondés sur le présent Rapport technique sont invitées à
l'absorption totale de polluant atmosphérique par le récepteur.
rechercher la possibilité d'appliquer les éditions les plus récen-
tes des normes indiquées ci-après. Les membres de la CE1 et de
Les lieux où l'émission ou I'immission se produisent sont définis
I'ISO possèdent le registre des Normes internationales en
par la surface enveloppante de la source ou du récepteur.
vigueur à un moment donné.
La transmission désigne collectivement des phénomènes qui
IS0 4225 : 1980, Qualité de l'air - Aspects généraux - Voca-
ont un effet sur les polluants atmosphériques dans I'atmos-
bulaire.
phère libre entre la source et le récepteur. Ces phénomènes
comprennent toutes les conséquences physiques dynamiques
IS0 4226 : 1980, Qualité de l'air - Aspects généraux - Unités
telles que la dilution de l'agent polluant dans l'air ainsi que les
de mesure.
réactions physiques et chimiques susceptibles de se produire.
IS0 6879 : 1983, Qualité de l'air - Caractéristiques de perfor-
Pour donner de ces concepts une expression quantitative, il
mance et concepts annexes pour les méthodes de mesure de la
convient d'employer des flux massiques ou des flux d'autre
qualité de l'air.
paramètre quantifiable et leurs dérivées. Les unités de mesure
sont données dans I'ISO 4225. La figure 1 illustre l'émission, la
IS0 7168 : 1985, Qualité de l'air - Présentation sous forme
transmission et I'immission. Des explications détaillées de ces
alphanumérique des données relatives à la qualité de l'air
concepts mathématiques sont données dans l'annexe A.
ambiant.
Conformément à ces définitions, I'immisson est un flux massi-
IS0 8601 : 1988, Éléments de données et formats d'échange - que ou un flux d'une autre caractéristique quantifiable, par
Échange d'imformation - Représentation de la date et de
unité de temps, qu'il convient de mesurer, si possible, au
l'heure. niveau du récepteur. Habituellement, il est nécessaire de con-
naître I'immission dans un certain nombre de récepteurs diffé-
IS0 9359 : 1989, Qualité de l'air - Échantillonnage stratifié rents et ne pas limiter ses mesures à un seul récepteur. II est de
pour l'évaluation de la qualité de l'air ambiant. règle qu'une étude d'ensemble de la pollution atmosphérique
soit conçue pour mesurer I'immission aux récepteurs et les con-
séquences éventuelles. En partant de cette idée, il est possible
d'en venir à l'idée de ((récepteur virtuel)) avec des surfaces uni-
3 Considérations générales
taires et des propriétés unitaires et d'étudier, pour chaque
récepteur de cette sorte, I'immission possible comme une fonc-
Toutes les tâches de contrôle de la qualité de l'air ambiant sont
tion de l'espace et du temps. Un récepteur virtuel pourrait être
conçues pour évaluer les conséquences sur l'environnement. II
n'est donc pas suffisant de se contenter de mesurer certains simulé par un système de mesure spécial, ou il pourrait avoir
une corrélation définie avec une concentration au niveau du sol
polluants atmosphériques. II est également nécessaire d'établir
ou du dépôt.
une corrélation entre les résultats de ces mesures et les effets
1

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ISO/TR 4227 : 1989 (FI
Transmission - Immission
Émission -
I Source
Figure 1 - Illustration des concepts d'émission, de transmission et d'immission
Déterminer l'efficacité de l'action du contrôle sur la
4 Formulation des tâches 4)
qualité de l'air ambiant?
4.1 Fixation des objectifs 5) Fournir des données en temps réel pour une alerte et
pour un système d'alarme?
Avant de commencer les mesures, il est essentiel de cerner
exactement le problème à résoudre et quelles contraintes il Déterminer les rapports entre la source et le récep-
6)
teur?
pourra entraîner sur un système de mesure «idéal».
7) Analyser les caractéristiques et les conséquences de
Un résumé des questions à se poser est donné ci-après.
la circulation locale des véhicules?
a) Le problème fondamental a-t-il été défini?
8) Indiquer les tendances en vue de répondre aux exi-
gences des plans d'implantation industriels et du plan
1) Y a-t-il un problème de pollution atmosphérique réel
d'urbanisme?
ou un problème potentiel?
9) Fournir des données en vue de modélisation urbaine
2) A-t-on besoin d'un système de contrôle?
opérationnelle?
3) Quels devraient être le but et les limitations du con-
101 Fournir des données pour échange d'informations
trôle?
interjuridictionnel?
b) Dans quelle mesure le problème fondamental se
11 I Se connecter à d'autres systèmes de contrôle?
rapporte-t-il aux fonctions de contrôle suivantes?
c) Quels sont les impératifs d'ordre économique et techni-
1) Quantifier la qualité de l'air ambiant et ses variations
que?
dans l'espace et dans le temps?
1) Quels sont les fonds disponibles et comment ceci se
2) Constituer la base d'un règlement du contrôle de la
rapporte-t-il à la fiabilité des données à obtenir sur la
pollution atmosphérique?
qualité de l'air ambiant?
3) Fournir des données pour un système de contrôle 2) Quelles sont les difficultés pour se procurer les fonds
intégré? nécessaires?
2

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ISO/TR 4227 : 1989 (FI
s'accroît avec chaque catégorie. Par exemple, l'établissement
3) Quelle est la main d'œuvre nécessaire pour assurer
le fonctionnement, l'entretien, la réparation, I'étalon- d'un diagnostic suppose qu'au préalable des faits aient été
déterminés, et toute prévision implique normalement qu'on ait
nage et l'évaluation des données sur la qualité de l'air
ambiant? déjà déterminé des faits et établi un diagnostic.
4) Quelles sont les compétences du personnel à exiger?
Dans la plupart des cas, il y aura lieu de faire des mesures pour
résoudre le problème. Cela signifie qu'il existera des incertitu-
5) Faut-il prévoir une formation du personnel?
des sur les données obtenues dues à l'erreur expérimentale, à
des paramètres de transmission inconnus, etc. En consé-
6) Peut-on mettre sur pied un planning réalisable?
quence, cela conduit à une incertitude sur les résultats que l'on
peut quantifier grâce à des méthodes statistiques. Pour cette
4.2 Classement par catégories fondamentales
raison, il est nécessaire de définir, en même temps que I'objec-
tif, la crédibilité statistique minimale (ou le degré d'incertitude)
Après avoir fixé les objectifs du contrôle, il importe de formuler
admissible pour que le problème puisse être résolu.
les tâches. Cependant, pour pouvoir le faire, il est avant tout
essentiel de répondre à un certain nombre de questions concer-
nant les objectifs de l'étude, la zone au-dessus de laquelle la
4.3.1 Determination des faits
qualité de l'air est à évaluer, la durée de l'étude et la manière
suivant laquelle les données obtenues doivent être analysées et
Par cette expression, on entend la constatation et I'enregistre-
présentées.
ment sur des documents des chiffres relatifs aux situations
d'émission, de transmission et d'immission. La détermination
II est suggéré de sérier les questions en les classant par catégo-
des concentrations au niveau du sol selon les différentes direc-
8 ries comme suit
tions du vent, etc., sont des exemples types.
a) Objectif
4.3.2 Diagnostic
1 . . . Détermination des faits
Un diagnostic est la découverte de la raison pour laquelle il
2 . . . Diagnostic
existe des situations particulières d'immission. En voici des
exemples : les immissions particulières dues à des conditions
3 . . . Prévision
spéciales d'émission ou de transmission, la localisation précise
b) Analyse et présentation des données
d'une source d'émission particulière, l'attribution des polluants
atmosphériques à une ou plusieurs sources spécifiques d'émis-
. 1 . . Tableau
sion, la détermination de la proportion dans laquelle une source
contribue à créer une situation d'immission définie.
. 2 . . Distribution des fréquences
. 3 . . Valeurs caractéristiques
Pour accomplir des tâches telles que celles-ci, la mesure des
seules concentrations des polluants atmosphériques au niveau
c) Zone d'évaluation de la qualité de l'air
du sol peut ne pas être suffisante, et il arrive qu'on ait à effec-
tuer des mesures supplémentaires ou à se procurer des infor-
. . I . Evaluation ponctuelle
mations sur l'émission, la transmission et leurs effets possibles
afin qu'une corrélation puisse être établie. II en sera ainsi pour
. . 2. Zone non quadrillée
l'identification de sources à la suite de plaintes, pour l'analyse
. . 3 . Zone quadrillée
de situations dans des conditions stationnaires, et pour la
détermination de la quantité relative de pollution atmosphéri-
d) Durée de l'étude d'ensemble
que attribuable au chauffage des locaux, à la circulation des
véhicules ou à d'autres sources dans des situations particuliè-
. . . 1 Échantillonnage d'air quasi instantané
res.
. . . 2 Echantillonnage programmé par période globale
4.3.3 Prévision
. . . 3 Échantillonnage quasi continu
II convient qu'une prévision donne des renseignements au sujet
L'ordre dans lequel ces catégories sont énumérées ne signifie
pas que les tâches doivent être traitées dans cet ordre. Le des immissions prévues pour l'avenir. II peut s'agir de prévi-
sions à long terme reposant sur des données climatiques ou sur
numérotage est un moyen d'indentifier les questions et les
plans d'échantillonnage correspondants. Ainsi attribue-t-on à des renseignements concernant des modifications suscep:ibles
de se produire dans l'émission ou la transmission, ou de prévi-
chaque tâche de contrôle de la qualité de l'air une identification
sions à court terme pour des conditions spéciales de transmis-
à quatre chiffres.
sion, par exemple, des conditions stationnaires, de direction et
Des détails sur cette classification sont donnés en 4.3 à 4.6.
de vitesse du vent, de réactions chimiques, de conditions spé-
ciales d'émission.
4.3 Objectif
Comme exemple type, on peut citer l'évolution à long terme
L'objectif peut essentiellement être divisé en l'une des trois des immissions due à une production industrielle accrue, aux
catégories : détermination des faits, diagnostic, prévision. La
conséquences des mesures d'affaiblissement de la pollution
quantité de données nécessaires pour résoudre le problème prévues, ou aux immissions résultant d'émissions accidentelles.
3

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ISO/TR 4227 : 1989 (FI
tant à la question. Ces tableaux fournissent les ensembles de
4.4 Analyse et présentation des données
données les plus importants permettant une évaluation géné-
L’analyse et la présentation des dqnnées doivent être en rela- rale pour une dépense minimale.
tion étroite avec l‘objectif de l’étude d’ensemble. L‘analyse des
Ces tableaux sont souvent une présentation des différentes
données doit produire suffisamment d‘informations pour résou-
interdépendances telles que l’interdépendance de I‘immission
dre le problème. Par exemple, les renseignements suivants peu-
sur l’émission ou sur la transmission. Ces interdépendances
vent s’avérer nécessaires :
sont généralement de nature aléatoire. Des exemples types de
a) valeurs quotidiennes moyennes de tous les polluants
ce genre de présentation sont
atmosphériques;
- tableaux des valeurs mesurées conformément aux
b) variations diurnes dans les concentrations de tous les
coordonnées des différents points d‘échantillonnage pen-
polluants atmosphériques;
dant des durées différentes, ou pour des conditions spécia-
les de transmission;
c) durée pendant laquelle, chaque jour, certaines valeurs
ont été dépassées (percentiles);
- tableaux des valeurs mesurées pour des points
d’échantillonnage sélectionnés, dans l‘ordre chronologique.
d) concentrations moyennes de polluants atmosphériques
sur certains sites quand le vent vient de certaines sources
dominantes:
4.4.2 Distribution des fréquences
e) distribution des fréquences;
La distribution des fréquences décrit le rapport entre les valeurs
f) valeurs maximales (par heure, par jour, par mois); d’une caractéristique et leur fréquence de renouvellement abso-
lue ou relative. Cette fréquence peut être présentée comme
g) analyse des régressions multiples.
étant réelle, relative ou cumulative et peut être exprimée sous
forme de tableau, de graphique (voir figure 2) ou par des coeffi-
II importe de veiller à ce que l‘analyse et la présentation des
cients d’une fonction. Un exemple type est celui des fréquen-
données en vue de corrélations spécifiques ne conduisent pas à
ces relatives auxquelles se produisent des valeurs mesurées
la perte de renseignements qui peuvent être requis à une date
dans des limites définies de concentration pour tous les points
ultérieure. Par exemple, la situation d’immission est complète-
de mesure dans une zone d‘évaluation pendant la durée pres-
ment décrite par une fonction dépendant du temps et du vec-
crite.
teur espace à trois dimensions dans la zone étudiée.
II y a lieu de noter que cette méthode de réduction des données
La fonction espace-temps mesurée pourrait être présentée soit
entraîne habituellement une perte par rapport aux renseigne-
pour chaque site comme une fonction du temps soit à un ins-
ments initiaux puisque l’identification individuelle de chaque
tant donné comme une fonction spatiale. La plupart du temps,
valeur mesurée a disparu quand on a procédé au calcul des
les problèmes sont beaucoup plus complexes et impliquent le
résumés statistiques.
fait que I’immission dépende de certains paramètres d’émission
et de transmission. Étant donné que ces paramètres sont égale-
ment des fonctions espace-temps, on peut en déduire les rela-
4.4.3 Valeurs caractéristiques
tions dont on a besoin si celles-ci et I’immission sont données
comme une fonction du temps et de l’espace. Par ailleurs,
Dans bien des cas, les résultats peuvent être exprimés par un
I’immission peut être présentée comme une fonction de ces
petit nombre de valeurs caractéristiques, par exemple I’estima-
a
paramètres eux-mêmes. En procédant ainsi, on perd des rensei-
tion moyenne des indices percentiles indiqués. Ceux-ci peuvent
gnements sur le temps et l‘espace. Par exemple, la dépendance
être déduits de la distribution des fréquences, ou calculés
de I‘immission par rapport à la direction du vent découle simple-
d’après la liste originale ou encore être obtenus directement
ment de ces deux fonctions : de I’immission considérée en tant
pendant le mesurage au moyen d‘une évaluation automatique.
que fonction du temps, de la direction du vent en tant que
La présentation des données par des valeurs caractéristiques
fonction du temps. Cependant, si les données sont réduites de
donne la proportion la plus élevée de réduction de données
cette façon, on perd l’information sur le temps et la dépen-
avec une perte correspondante des informations initiales.
dance de I‘immission par rapport au temps ne peut être récupé-
rée s’il s’avère nécessaire de procéder à des recherches supplé-
mentaires sur les conséquences des autres paramètres. Ces
4.5 Zone d’évaluation
aspects doivent donc être considérés attentivement lorsqu’on
met en place un plan de mesures et qu’on décide de I’appareil-
Dans la plupart des cas, il est nécessaire d’évaluer I’immission
lage.
par rapport à un certain nombre de récepteurs différents possi-
bles et non pas pour un seul récepteur spécial localisé en un
La présentation des données peut être faite de trois manières
certain point. Pour cette raison, on utilise la notion de récep-
différentes, comme décrit en 4.4.1 à 4.4.3.
teurs virtuels. Pour une étude des concentrations au niveau du
sol, la surface d‘un récepteur virtuel pourrait être placée à une
4.4.1 Tableaux certaine hauteur au-dessus du niveau du sol, tandis que pour
une étude sur la corrosion des bâtiments, on pourrait choisir
C’est la présentation des données sous forme de listes, telles
une surface ayant la forme de ce bâtiment. II convient que les
que les valeurs mesurées de I‘immission ou de ce qui en tient
systèmes de mesure soient placés de façon à donner des
lieu, selon l‘endroit, le temps ou d‘autres paramètres se rappor-
valeurs représentatives de la surface totale.
4

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ISO/TR 4227 : 1989 (FI
100r
20
1
10
t O
bi
O
Concentration au niveau du sol Concentration au niveau du sol Concentration au niveau du sol
Figure 2 - Exemples de présentations graphiques de la distribution des fréquences
La zone d’évaluation peut être décrite par des coordonnées taire n’est ni possible ni nécessaire pour l‘évaluation de I’immis-
sion. Le point d’évaluation est représenté par le système de
fixes ou mobiles et elle peut comporter une seule zone ou un
certain nombre de sous-zones différentes. Par exemple, la mesure employé. Des points d’évaluation isolés peuvent, selon
le cas, être stationnaires ou mobiles, par exemple une personne
tâche du mesurage est complètement définie en ce qui con-
cerne la zone s’il est possible d’en fixer les limites ou d‘en don- ou un point situé 5 km dans le sens du vent en aval d‘une
source. Un certain nombre de points indépendants combinés
ner une définition conformément aux critères suivants :
en une seule zone d’évaluation pourraient s’appliquer au cas
-
critères géographiques ou frontières entre pays; d’une aire de jeux (voir figure 3).
-
sources ou groupes spéciaux de sources;
4.5.2 Zone non quadrillée
-
conditions spéciales de transmission, ou objets spé-
Une zone d’évaluation non quadrillée peut être constituée
ciaux à protéger.
d‘une zone ou de plusieurs zones. Lorsqu’on veut connaître
Pour des raisons pratiques, le mieux consiste à distinguer trois I’immission pour chaque zone considérée comme un tout, et
catégories de zones d‘évaluation, à savoir: une évaluation qu‘il est nécessaire d’avoir plusieurs sites d’échantillonnage
ponctuelle, une zone non quadrillée et une zone quadrillée (voir pour chaque zone, la résolution spatiale n‘est pas nécessaire
figure 3). Dans chacun de ces trois cas, les emplacements (voir figure 3). On peut en prendre pour exemple, la détermina-
tion de la moyenne des concentrations de dioxyde de soufre
d’échantillonnage sont choisis différemment. Si la zone d’éva-
luation comporte un seul ou plusieurs points fixes, les emplace- dans une zone industrielle où il peut y avoir plus d‘un site
ments d’échantillonnage sont donnés directement par l’énoncé d‘échantillonnage et où aucune résolution spatiale de I‘immis-
du problème. Si la zone d’évaluation se compose d’une seule Sion n’est nécessaire entre les sites. Comme autre exemple
ou de plusieurs zones qui sont à évaluer sans résolution spa- d’évaluation d‘un nombre de sous-zones, on peut citer la déter-
tiale, le mesurage peut être effectué sur des échantillons au mination du taux de fréquence d’une concentration de dioxyde
hasard. Le nombre et la répartition des sites d‘échantillonnage de soufre de 75 % dans les zones industrielles, résidentielles et
sont déterminés par la variance du critère mesuré et la précision de loisirs d‘une ville.
requise. Si une zone est à évaluer en fonction de la localisation
de I’immission, le nombre et la distribution des sites d’échantil-
lonnage dépendent aussi de la résolution spatiale requise.
4.5.3 Zone quadrillée
A l’intérieur d’une zone d‘évaluation, il convient que I’immis-
4.5.1 Évaluation ponctuelle sion soit évaluée en fonction de l‘espace. Cela signifie que
l‘énoncé du problème doit fixer une certaine résolution spatiale
La zone d’évaluation peut comporter un point ou plusieurs
(voir figure 3). La puissance de la résolution spatiale est donnée
points d‘évaluation choisis indépendamment les uns des autres par la densité du point d’échantillonnage, la précision du mesu-
dans l‘espace. Un point d‘évaluation est défini comme une rage et les éventuels renseignements supplémentaires concer-
petite zone continue dans laquelle une subdivision supplémen- nant la distribution spatiale de I’immission. S’il est nécessaire
5

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ISO/TR 4227 : 1989 (FI
de la zone d'évaluation, OU la détermination de la diminution de
de faire une évaluation dans un temps limité, la résolution spa-
la concentration de monoxyde de carbone à mesure que
tiale dépend en outre de la variance du critère à mesurer et par
à une grande route pendant que le vent
s'accroît la distance
conséquent de la fréquence du mesurage. On peut prendre
souffle dans certaine direction, la connaissance de la distribu-
pour exemple, la détermination de lignes d'égale concentration
tion de l'émission servant de renseignement supplémentaire.
moyenne où une certaine valeur lim
...