SIST ISO 5667-10:2021

INTERNATIONAL ISO
STANDARD 5667-10
Second edition
2020-11
Water quality — Sampling —
Part 10:
Guidance on sampling of waste water
Qualité de l'eau — Échantillonnage —
Partie 10: Lignes directrices pour l'échantillonnage des eaux
résiduaires
Reference number
ISO 5667-10:2020(E)
©
ISO 2020

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ISO 5667-10:2020(E)

COPYRIGHT PROTECTED DOCUMENT
© ISO 2020
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting
on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address
below or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: +41 22 749 01 11
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii © ISO 2020 – All rights reserved

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ISO 5667-10:2020(E)

Contents Page
Foreword .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 General aspects . 3
4.1 Design of sampling programme . 3
4.2 Sampling point selection - Representativeness . 3
4.3 Frequency and time of sampling . 4
4.3.1 Number of samples . 4
4.3.2 Sampling time for effluent stream . 4
5 Sampling at specific locations. 5
5.1 Sampling from sewers, channels and manholes . 6
5.2 Sampling from waste water treatments plants . 6
5.3 Sampling from industrial sites . 7
5.4 Sampling from cooling systems . 7
6 Main types of waste water sampling . 8
6.1 Spot sampling . 8
6.2 Composite sampling . 8
7 Waste water sampling . 9
7.1 General aspects . 9
7.1.1 Preparation of the sampling campaign . 9
7.1.2 Arrival on site . 9
7.2 Composite sampling for waste water quality monitoring .10
7.2.1 General.10
7.2.2 Automatic composite sampling .10
7.2.3 Manual composite sampling .13
7.2.4 Manual sample reconstitution .13
7.3 Spot sampling in an effluent stream .14
7.3.1 General.14
7.3.2 Direct sampling .15
7.3.3 Indirect sampling .15
7.3.4 Automatic, remote start or event-triggered sampling.16
7.4 Spot sampling of tanks — planned discharges .16
8 Sampling equipment .17
8.1 General .17
8.2 Automatic sampler .17
8.3 Manual sampling equipment .18
8.3.1 General.18
8.3.2 Ballasted sample collector .18
8.3.3 Bucket, vertical water sampler .18
8.4 Tank sampling equipment .19
8.4.1 Mixing .19
8.4.2 Sampling equipment . . .19
9 Homogenization, preservation, transport and storage of samples .19
9.1 Homogenization of collected volume .19
9.2 Distribution of collected volume into laboratory bottles .20
9.3 Preservation and packaging of samples .21
9.4 Transportation and reception .21
9.4.1 General.21
9.4.2 Time .21
9.4.3 Temperature .21
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ISO 5667-10:2020(E)

9.5 Security and traceability of samples during storage and delivery .22
9.5.1 Routine samples .22
9.5.2 Samples which might be used for legal purposes .22
10 Quality assurance .22
10.1 Avoidance of contamination .22
10.2 Sample identification and records .23
10.3 Assurance and quality control .23
11 Reports.23
11.1 Analytical reports .23
11.2 Sampling protocols .24
12 Safety precautions .24
12.1 General .24
12.2 Personnel safety .25
12.3 Equipment safety .25
Annex A (informative) Examples of sampling from tanks .27
Annex B (informative) Advantages and disadvantages of main types of waste water sampling .30
Annex C (informative) Example of cleaning protocol — Sampling equipment .32
Annex D (informative) Example of field form — Waste water sampling .34
Annex E (informative) Choice of compatible materials for automatic samplers .36
Annex F (informative) Comparison of types of pumping: peristaltic pump (PP) and vacuum
pump (VAP) .38
Annex G (informative) Type of distribution of collected volume into laboratory bottle .40
Annex H (informative) Quality control of sampling equipment .42
Annex I (informative) Bias and repeatability .44
Bibliography .45
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ISO 5667-10:2020(E)

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. Each 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, governmental 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 procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www .iso .org/ directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www .iso .org/ patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to the
World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see www .iso .org/
iso/ foreword .html.
This document was prepared by Technical Committee ISO/TC 147, Water quality, SC 6, Sampling (general
methods).
This second edition cancels and replaces the first edition (ISO 5667-10:1992), which has been technically
revised. The main changes compared to the previous edition are as follows:
— integration of radioactive liquid effluent sampling and its specificities;
— integration of qualified spot sampling.
A list of all parts in the ISO 5667 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www .iso .org/ members .html.
© ISO 2020 – All rights reserved v

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INTERNATIONAL STANDARD ISO 5667-10:2020(E)
Water quality — Sampling —
Part 10:
Guidance on sampling of waste water
1 Scope
This document contains details on the sampling of domestic and industrial waste water, i.e. the design
of sampling programmes and techniques for the collection of samples. It covers waste water in all its
forms, i.e. industrial waste water, radioactive waste water, cooling water, raw and treated domestic
waste water.
It deals with various sampling techniques used and the rules to be applied so as to ensure the samples
are representative.
Sampling of accidental spillages is not included, although the methods described in certain cases may
also be applicable to spillages.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated
references, only the edition cited applies. For undated references, the latest edition of the referenced
document (including any amendments) applies.
ISO 5667-1, Water quality — Sampling — Part 1: Guidance on the design of sampling programmes and
sampling techniques
ISO 5667-3, Water quality — Sampling — Part 3: Preservation and handling of water samples
ISO 5667-7, Water quality — Sampling — Part 7: Guidance on sampling of water and steam in boiler plants
ISO 5667-14, Water quality — Sampling — Part 14: Guidance on quality assurance and quality control of
environmental water sampling and handling
ISO 5667-16, Water quality — Sampling — Part 16: Guidance on biotesting of samples
ISO 6107 (all parts), Water quality — Vocabulary
ISO 19458, Water quality — Sampling for microbiological analysis
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 6107 (all parts) and the
following apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at http:// www .electropedia .org/
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ISO 5667-10:2020(E)

3.1
composite sample
two or more samples or sub-samples, mixed together in appropriately known proportions (either
discretely or continuously), from which the average value of a desired characteristic may be obtained
Note 1 to entry: The number of samples or sub samples are usually based on time, flow measurements, area or
depth profile sampling.
EXAMPLE Composite sample can be made in different ways:
— constant volume variable time sampling (C.V.V.T): flow proportional sampling based on collecting equal
volumes of sample at frequencies proportional to flow.
— constant time variable volume sampling (C.T.V.V): flow proportional sampling based on collecting samples at
fixed time intervals but where the volume of sample is varied in proportion to the flow.
— constant time constant volume sampling (C.T.C.V): equal volumes of sample or sub-sample collected at equal
increments of time.
3.2
sampling point
precise position within a sampling location from which samples are taken
3.3
spot sample
discrete sample taken randomly (with regard to time and/or location) from a body of water, usually
taken manually, but may be taken by automatic sampling equipment or by event-triggered automatic
samplers
3.4
qualified spot sample
special form of a composite sample (3.1), consisting of at least five spot samples, taken and mixed within
a maximum period of two hours and at an interval of not less than two minutes
3.5
radioactive liquid effluent
water or waste water that contains radioactive substances, resulting from a process and that can be
recycled, treated and/or discharged to the environment
Note 1 to entry: The activity concentration of the radioactive liquid effluent is usually measured before being
discharged in the environment to verify that it is lower than the authorized levels in order to comply with
national regulation.
3.6
supernatant
solid or liquid phase present on the surface of an effluent
3.7
planned discharge
discharge subject to prior agreement further to a consultation between several parties based on
knowing certain predefined parameters and referring to limit values (regulatory or otherwise)
Note 1 to entry: These parameters may, for example, be physical, chemical and radiological measurements, the
estimated discharge volume, the discharge period or the maximum discharge flow rate.
3.8
permanent discharge
direct discharge into a channel or collector or water body, which is not subject to a specific prior
agreement, but which shall conform with limit values
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ISO 5667-10:2020(E)

3.9
tank
hollow object, very variable in size, used to hold liquids
Note 1 to entry: Covers the usual names such as tank, chamber and pool. The content of this tank is intended for
direct and indirect liquid discharge to the environment or to a specific treatment.
3.10
event-trigged sampling
sampling which is triggered because a pre-determined criterion has been met (e.g. rainfall, change in
electrical conductivity, pH or the introduction of a polluting substance), when samples should be taken
manually or by automatic equipment
4 General aspects
4.1 Design of sampling programme
Sampling is usually the first step in carrying out an investigation and largely determines the quality
of the whole investigation. It is therefore recommended that a detailed sampling strategy be drawn
up, often based upon a preliminary investigation in which an assessment has identified the important
aspects. Both the purpose and the ambient situation determine the way in which the sampling is carried
out. General aspects for sampling programme design can be found in ISO 5667-1.
4.2 Sampling point selection - Representativeness
The sampling point selection should be representative of the waste stream to be examined. In some
waste waters this representativeness may be difficult to obtain because of the spatial and temporal
heterogeneity of the water body. It is necessary to carry out the sampling in the sections where the flow
is well mixed and homogeneous.
The term “representativeness” encompasses two notions depending on the type of environment to be
sampled:
— representativeness in a flow (canal, sewer, manhole, pressurised pipes, etc.);
— representativeness in a storage (tank, lagoons, basins, etc.).
These two notions should be treated in different ways, but the goal remains to obtain a representative
sample of the water body.
Sampling points may be clearly identified (by regulatory text) or not, in which case a preliminary
investigation is recommended. This is generally the case for the selection of sewer sampling locations.
By studying drawings of the sewer system initially, possible locations can be identified. Subsequently, a
site inspection should be conducted to ensure that the locations of the sewers and the path of the waste
stream corresponds to the drawings, and to make sure that the selected location is representative for
the sampling purpose. The tracer studies may be a helpful tool.
Each sampling point should be documented. It is important to gather, for example, the following
information: identification, location of the site, photos, geographical coordinates, site location, type of
flow (open, closed), access conditions and sampling technique.
If necessary, specifically describe and label the sampling site. Select the site so that representative
samples can be obtained and the waste water flow (with the exception of fixed sampling equipment) is
clearly visible from the sampling site.
The following facilities should be available for the for the sampling sites involving a fixed automatic
sampling device:
— access for motor vehicles to the immediate vicinity of the sampling site;
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ISO 5667-10:2020(E)

— flat working surfaces at appropriate height above the sampling point for the set-up of sampling
devices;
— adequate lighting and power connection;
— water connection to clean the equipment after sampling;
— adequate safety precautions (e.g. grids, railings, fall arresting devices); and
— flow meters in the case of a flow-dependent sampling.
If the hydraulic conditions do not ensure the representativeness of the sample (absence of flow, reduced
activity, abnormal load rise), this unusual situation should be noted on the sampling report and the
client and the analytical laboratory should be informed.
4.3 Frequency and time of sampling
4.3.1 Number of samples
Analyses should be based on samples taken at regular intervals during a certain period (composite
or spot). The decision on the required number of samples taken during each period should be decided
[1] [2]
based on statistical techniques (see ISO 2602, ISO 3534 (all parts) and ISO 5667-1). But the number
of samples to be taken may often be decided by the regulatory body or pollution control authorities.
4.3.2 Sampling time for effluent stream
The objective of a sampling programme often dictates when and how a sample is collected and is often
determined by legislation or directives. Generally, when sampling sewages and effluents, it is normal to
make allowances for the following sources of variation in quality:
a) diurnal variations (i.e. within-day variability);
b) variations between days of the week;
c) variations between weeks and months;
d) variations between seasons;
e) variations due to storm water episodes; and
f) trends.
If there is little or no diurnal variation, or day-to-day variations, then the particular time of day or day
of the week for sampling is relatively unimportant.
If the identification of the nature and magnitude of peak load are important, sampling should be
restricted to those periods of the day, week or month when peak loads are known to occur.
Relating the times of sampling to the particular process being monitored may be very important when
considering industrial effluent discharges that are either seasonal or operated on a batch basis. In
either case, the discharge will not be continuous, and the sampling programme will need to take this
fact into account.
Sampling for the detection of trends needs careful planning. For example, when detecting trends on a
month-to-month basis, it can be appropriate to always sample on the same day of the week, in order
that any diurnal and daily variations are eliminated from the overall variability of data, thus allowing
trends to be more efficiently detected.
When the number of samples has been decided upon according to 4.3.1, the sampling times should be
determined. The samples should normally be taken at fixed intervals during the whole control period.
The sampling period may be one year, a number of months or weeks, or even shorter periods of time.
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ISO 5667-10:2020(E)

If the sampling period covers one year, the days of sampling may be determined using a formula. An
example of this is:
Formula (1) for a number of samples (n), larger than about 25 and from Formula (2) for a number of
samples less than about 25.
Formula (1) indicates the day number during which sampling should take place.
365 365×2 365×3 365×n
A++,,A A+ ,.,A+ (1)
n n n n
where
n is the number of samples;
A 365
is a random number in the interval between − and 0.
n
Formula (2) indicates the week number during which the sampling should take place. The day of each
week should be determined so that samples are taken on every weekday.
52 52×2523× 52×n
B++,,B B+ ,.,B+ (2)
n n n n
where
n is the number of samples;
B 52
is a random number in the interval between − and 0.
n
Similar formulae can be used for other periods, for example, one month, three months, six months, etc.
The period chosen should cover any seasonal variations.
After determining the intervals and the day or week number, it should be ensured that the sampling
does not lead to any risk of systematic error, for example by always taking samples on one day, or by
systematically omitting weekdays.
5 Sampling at specific locations
The concentration profiles of dissolved substances and suspended solids measure
...

SLOVENSKI STANDARD
oSIST ISO/PRF 5667-10:2020
01-oktober-2020
Kakovost vode - Vzorčenje - 10. del: Navodilo za vzorčenje odpadnih vod
Water quality - Sampling - Part 10: Guidance on sampling of waste waters
Qualité de l'eau - Échantillonnage - Partie 10: Guide pour l'échantillonnage des eaux
résiduaires
Ta slovenski standard je istoveten z: ISO/PRF 5667-10
ICS:
13.060.30 Odpadna voda Sewage water
13.060.45 Preiskava vode na splošno Examination of water in
general
oSIST ISO/PRF 5667-10:2020 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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oSIST ISO/PRF 5667-10:2020

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oSIST ISO/PRF 5667-10:2020
INTERNATIONAL ISO
STANDARD 5667-10
Second edition
Water quality — Sampling —
Part 10:
Guidance on sampling of waste water
Qualité de l'eau — Échantillonnage —
Partie 10: Lignes directrices pour l'échantillonnage des eaux
résiduaires
PROOF/ÉPREUVE
Reference number
ISO 5667-10:2020(E)
©
ISO 2020

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oSIST ISO/PRF 5667-10:2020
ISO 5667-10:2020(E)

COPYRIGHT PROTECTED DOCUMENT
© ISO 2020
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting
on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address
below or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: +41 22 749 01 11
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii PROOF/ÉPREUVE © ISO 2020 – All rights reserved

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oSIST ISO/PRF 5667-10:2020
ISO 5667-10:2020(E)

Contents Page
Foreword .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 General aspects . 3
4.1 Design of sampling programme . 3
4.2 Sampling point selection - Representativeness . 3
4.3 Frequency and time of sampling . 4
4.3.1 Number of samples . 4
4.3.2 Sampling time for effluent stream . 4
5 Sampling at specific locations. 5
5.1 Sampling from sewers, channels and manholes . 5
5.2 Sampling from waste water treatments plants . 6
5.3 Sampling from industrial sites . 7
5.4 Sampling from cooling systems . 7
6 Main types of waste water sampling . 8
6.1 Spot sampling . 8
6.2 Composite sampling . 8
7 Waste water sampling . 9
7.1 General aspects . 9
7.1.1 Preparation of the sampling campaign . 9
7.1.2 Arrival on site . 9
7.2 Composite sampling for waste water quality monitoring .10
7.2.1 General.10
7.2.2 Automatic composite sampling .10
7.2.3 Manual composite sampling .13
7.2.4 Manual sample reconstitution .13
7.3 Spot sampling in an effluent stream .14
7.3.1 General.14
7.3.2 Direct sampling .14
7.3.3 Indirect sampling .15
7.3.4 Automatic, remote start or event-triggered sampling.15
7.4 Spot sampling of tanks — planned discharges .15
8 Sampling equipment .16
8.1 General .16
8.2 Automatic sampler .17
8.3 Manual sampling equipment .17
8.3.1 General.17
8.3.2 Ballasted sample collector .18
8.3.3 Bucket, vertical water sampler .18
8.4 Tank sampling equipment .18
8.4.1 Mixing .18
8.4.2 Sampling equipment . . .18
9 Homogenization, preservation, transport and storage of samples .19
9.1 Homogenization of collected volume .19
9.2 Distribution of collected volume into laboratory bottles .20
9.3 Preservation and packaging of samples .20
9.4 Transportation and reception .21
9.4.1 General.21
9.4.2 Time .21
9.4.3 Temperature .21
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oSIST ISO/PRF 5667-10:2020
ISO 5667-10:2020(E)

9.5 Security and traceability of samples during storage and delivery .21
9.5.1 Routine samples .21
9.5.2 Samples which might be used for legal purposes .22
10 Quality assurance .22
10.1 Avoidance of contamination .22
10.2 Sample identification and records .22
10.3 Assurance and quality control .23
11 Reports.23
11.1 Analytical reports .23
11.2 Sampling protocols .24
12 Safety precautions .24
12.1 General .24
12.2 Personnel safety .24
12.3 Equipment safety .25
Annex A (informative) Examples of sampling from tanks .26
Annex B (informative) Advantages and disadvantages of main types of waste water sampling .29
Annex C (informative) Example of cleaning protocol — Sampling equipment .31
Annex D (informative) Example of field form — Waste water sampling .33
Annex E (informative) Choice of compatible materials for automatic samplers .35
Annex F (informative) Comparison of types of pumping: peristaltic pump (PP) and vacuum
pump (VAP) .37
Annex G (informative) Type of distribution of collected volume into laboratory bottle .39
Annex H (informative) Quality control of sampling equipment .41
Annex I (informative) Bias and repeatability .43
Bibliography .44
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oSIST ISO/PRF 5667-10:2020
ISO 5667-10:2020(E)

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. Each 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, governmental 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 procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www .iso .org/ directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www .iso .org/ patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to the
World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see www .iso .org/
iso/ foreword .html.
This document was prepared by Technical Committee ISO/TC 147, Water quality, SC 6, Sampling (general
methods).
This second edition cancels and replaces the first edition (ISO 5667-10:1992), which has been technically
revised. The main changes compared to the previous edition are as follows:
— integration of radioactive liquid effluent sampling and its specificities;
— integration of qualified spot sampling.
A list of all parts in the ISO 5667 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www .iso .org/ members .html.
© ISO 2020 – All rights reserved PROOF/ÉPREUVE v

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oSIST ISO/PRF 5667-10:2020

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oSIST ISO/PRF 5667-10:2020
INTERNATIONAL STANDARD ISO 5667-10:2020(E)
Water quality — Sampling —
Part 10:
Guidance on sampling of waste water
1 Scope
This document contains details on the sampling of domestic and industrial waste water, i.e. the design
of sampling programmes and techniques for the collection of samples. It covers waste water in all its
forms, i.e. industrial waste water, radioactive waste water, cooling water, raw and treated domestic
waste water.
It deals with various sampling techniques used and the rules to be applied so as to ensure the samples
are representative.
Sampling of accidental spillages is not included, although the methods described in certain cases may
also be applicable to spillages.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated
references, only the edition cited applies. For undated references, the latest edition of the referenced
document (including any amendments) applies.
ISO 5667-1, Water quality — Sampling — Part 1: Guidance on the design of sampling programmes and
sampling techniques
ISO 5667-3, Water quality — Sampling — Part 3: Preservation and handling of water samples
ISO 5667-16, Water quality — Sampling — Part 16: Guidance on biotesting of samples
ISO 19458, Water quality — Sampling for microbiological analysis
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
For the purposes of this document, the terms and definitions given in ISO 6107 (all parts) and the
following apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at http:// www .electropedia .org/
3.1
composite sample
two or more samples or sub-samples, mixed together in appropriately known proportions (either
discretely or continuously), from which the average value of a desired characteristic may be obtained
Note 1 to entry: The number of samples or sub samples are usually based on time, flow measurements, area or
depth profile sampling.
EXAMPLE Composite sample can be made in different ways:
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oSIST ISO/PRF 5667-10:2020
ISO 5667-10:2020(E)

- constant volume variable time sampling (C.V.V.T): flow proportional sampling based on collecting equal
volumes of sample at frequencies proportional to flow.
- constant time variable volume sampling (C.T.V.V): flow proportional sampling based on collecting samples at
fixed time intervals but where the volume of sample is varied in proportion to the flow.
- constant time constant volume sampling (C.T.C.V): equal volumes of sample or sub-sample collected at equal
increments of time.
3.2
sampling point
precise position within a sampling location from which samples are taken
3.3
spot sample
discrete sample taken randomly (with regard to time and/or location) from a body of water, usually
taken manually, but may be taken by automatic sampling equipment or by event-triggered automatic
samplers
3.4
qualified spot sample
special form of a composite sample (3.1), consisting of at least five spot samples, taken and mixed within
a maximum period of two hours and at an interval of not less than two minutes
3.5
radioactive liquid effluent
water or waste water that contains radioactive substances, resulting from a process and that can be
recycled, treated and/or discharged to the environment
Note 1 to entry: Note to entry: The activity concentration of the radioactive liquid effluent is usually measured
before being discharged in the environment to verify that it is lower than the authorized levels in order to comply
with national regulation
3.6
supernatant
solid or liquid phase present on the surface of an effluent
3.7
planned discharge
discharge subject to prior agreement further to a consultation between several parties based on
knowing certain predefined parameters and referring to limit values (regulatory or otherwise)
Note 1 to entry: Note to entry: These parameters may, for example, be physicalchemical and radiological
measurements, the estimated discharge volume, the discharge period or the maximum discharge flow rate.
3.8
permanent discharge
direct discharge into a channel or collector or water body, which is not subject to a specific prior
agreement, but which shall comply with limit values
3.9
tank
hollow object, very variable in size, used to hold liquids.
Note 1 to entry: Covers the usual names such as tank, chamber and pool. The content of this tank is intended for
direct and indirect liquid discharge to the environment or to a specific treatment
3.10
event-trigged sampling
sampling which is triggered because a pre-determined criterion has been met (e.g. rainfall, change in
electrical conductivity, pH or the introduction of a polluting substance), when samples should be taken
manually or by automatic equipment
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oSIST ISO/PRF 5667-10:2020
ISO 5667-10:2020(E)

4 General aspects
4.1 Design of sampling programme
Sampling is usually the first step in carrying out an investigation and largely determines the quality
of the whole investigation. It is therefore recommended that a detailed sampling strategy be drawn
up, often based upon a preliminary investigation in which an assessment has identified the important
aspects. Both the purpose and the ambient situation determine the way in which the sampling is carried
out. General aspects for sampling programme design can be found in ISO 5667-1.
4.2 Sampling point selection - Representativeness
The sampling point selection should be representative of the waste stream to be examined. In some
waste waters this representativeness may be difficult to obtain because of the spatial and temporal
heterogeneity of the water body. It is necessary to carry out the sampling in the sections where the flow
is well mixed and homogeneous.
The term “representativeness” encompasses two notions depending on the type of environment to be
sampled:
— representativeness in a flow (canal, sewer, manhole, pressurised pipes, etc.);
— representativeness in a storage (tank, lagoons, basins, etc.).
These two notions should be treated in different ways, but the goal remains to obtain a representative
sample of the water body.
Sampling points may be clearly identified (by regulatory text) or not, in which case a preliminary
investigation is recommended. This is generally the case for the selection of sewer sampling locations.
By studying drawings of the sewer system initially, possible locations can be identified. Subsequently, a
site inspection should be conducted to ensure that the locations of the sewers and the path of the waste
stream corresponds to the drawings, and to make sure that the selected location is representative for
the sampling purpose. The tracer studies may be a helpful tool.
Each sampling point should be documented. It is important to gather, for example, the following
information: identification, location of the site, photos, geographical coordinates, site location, type of
flow (open, closed), access conditions and sampling technique.
If necessary, specifically describe and label the sampling site. Select the site so that representative
samples can be obtained and the waste water flow (with the exception of fixed sampling equipment) is
clearly visible from the sampling site.
The following facilities should be available for the for the sampling sites involving a fixed automatic
sampling device:
— access for motor vehicles to the immediate vicinity of the sampling site;
— flat working surfaces at appropriate height above the sampling point for the set-up of sampling
devices;
— adequate lighting and power connection;
— water connection to clean the equipment after sampling;
— adequate safety precautions (e.g. grids, railings, fall arresting devices); and
— flow meters in the case of a flow-dependent sampling.
If the hydraulic conditions do not ensure the representativeness of the sample (absence of flow, reduced
activity, abnormal load rise), this unusual situation should be noted on the sampling report and the
client and the analytical laboratory should be informed.
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ISO 5667-10:2020(E)

4.3 Frequency and time of sampling
4.3.1 Number of samples
Analyses should be based on samples taken at regular intervals during a certain period (composite
or spot). The decision on the required number of samples taken during each period should be decided
[1] [2]
based on statistical techniques (see ISO 2602, ISO 3534 (all parts) and ISO 5667-1). But the number
of samples to be taken may often be decided by the regulatory body or pollution control authorities.
4.3.2 Sampling time for effluent stream
The objective of a sampling programme often dictates when and how a sample is collected and is often
determined by legislation or directives. Generally, when sampling sewages and effluents, it is normal to
make allowances for the following sources of variation in quality:
a) diurnal variations (i.e. within-day variability);
b) variations between days of the week;
c) variations between weeks and months;
d) variations between seasons;
e) variations due to storm water episodes; and
f) trends.
If there is little or no diurnal variation, or day-to-day variations, then the particular time of day or day
of the week for sampling is relatively unimportant.
If the identification of the nature and magnitude of peak load are important, sampling should be
restricted to those periods of the day, week or month when peak loads are known to occur.
Relating the times of sampling to the particular process being monitored may be very important when
considering industrial effluent discharges that are either seasonal or operated on a batch basis. In
either case, the discharge will not be continuous, and the sampling programme will need to take this
fact into account.
Sampling for the detection of trends needs careful planning. For example, when detecting trends on a
month-to-month basis, it can be appropriate to always sample on the same day of the week, in order
that any diurnal and daily variations are eliminated from the overall variability of data, thus allowing
trends to be more efficiently detected.
When the number of samples has been decided upon according to 4.3.1, the sampling times should be
determined. The samples should normally be taken at fixed intervals during the whole control period.
The sampling period may be one year, a number of months or weeks, or even shorter periods of time.
If the sampling period covers one year, the days of sampling may be determined using a formula. An
example of this is:
Formula (1) for a number of samples (n), larger than about 25 and from formula (2) for a number of
samples less than about 25.
Formula (1) indicates the day number during which sampling should take place.
365 365×2 365×3 365×n
A++,,A A+ ,.,A+ (1)
n n n n
where
4 PROOF/ÉPREUVE © ISO 2020 – All rights re
...

DRAFT INTERNATIONAL STANDARD
ISO/DIS 5667-10
ISO/TC 147/SC 6 Secretariat: BSI
Voting begins on: Voting terminates on:
2019-07-04 2019-09-26
Water quality — Sampling —
Part 10:
Guidance on sampling of waste water
Qualité de l'eau — Échantillonnage —
Partie 10: Lignes directrices pour l'échantillonnage des eaux résiduaires
ICS: 13.060.30
THIS DOCUMENT IS A DRAFT CIRCULATED
FOR COMMENT AND APPROVAL. IT IS
THEREFORE SUBJECT TO CHANGE AND MAY
NOT BE REFERRED TO AS AN INTERNATIONAL
STANDARD UNTIL PUBLISHED AS SUCH.
IN ADDITION TO THEIR EVALUATION AS
BEING ACCEPTABLE FOR INDUSTRIAL,
This document is circulated as received from the committee secretariat.
TECHNOLOGICAL, COMMERCIAL AND
USER PURPOSES, DRAFT INTERNATIONAL
STANDARDS MAY ON OCCASION HAVE TO
BE CONSIDERED IN THE LIGHT OF THEIR
POTENTIAL TO BECOME STANDARDS TO
WHICH REFERENCE MAY BE MADE IN
Reference number
NATIONAL REGULATIONS.
ISO/DIS 5667-10:2019(E)
RECIPIENTS OF THIS DRAFT ARE INVITED
TO SUBMIT, WITH THEIR COMMENTS,
NOTIFICATION OF ANY RELEVANT PATENT
RIGHTS OF WHICH THEY ARE AWARE AND TO
©
PROVIDE SUPPORTING DOCUMENTATION. ISO 2019

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DRAFT INTERNATIONAL STANDARD ISO/DIS 5667‐10:2019(E)
ISO/DIS 5667-10:2019(E)


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below or ISO’s member body in the country of the requester.
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ii © ISO 2019 – All rights reserved

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DRAFT INTERNATIONAL STANDARD ISO/DIS 5667‐10:2019(E)

COPYRIGHT PROTECTED DOCUMENT
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or
utilized otherwise in any form or by any means, electronic or mechanical, including
photocopying, or posting on the internet or an intranet, without prior written permission.
Permission can be requested from either ISO at the address below or ISO’s member body in the
country of the requester.
ISO copyright office
Ch. de Blandonnet 8  CP 401
CH‐1214 Vernier, Geneva, Switzerland
Tel. + 41 22 749 01 11
Fax + 41 22 749 09 47
copyright@iso.org
www.iso.org
© ISO 2019 – All rights reserved
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ISO/DIS 5667-10:2019(E)
Contents Page
Foreword . 4
1 Scope . 5
2 Normative references . 5
3 Terms and definitions . 5
4 General aspects . 7
4.1 Design of sampling programme . 7
4.2 Sampling point selection ‐ Representativeness . 7
4.3 Frequency and time of sampling . 8
5 Sampling at specific locations . 9
5.1 Sampling from sewers, channels and manholes . 10
5.2 Sampling from waste water treatments plants . 10
5.3 Sampling from industrial sites . 11
5.4 Sampling from cooling systems . 12
6 Main types of waste water sampling . 12
6.1 Spot sampling . 12
6.2 Composite sampling . 13
7 Waste water sampling . 13
7.1 General aspects . 13
7.2 Composite sampling for waste water quality monitoring . 14
7.3 Spot sampling in an effluent stream . 19
7.4 Spot sampling of tank — planned discharges . 20
8 Sampling equipment . 22
8.1 General . 22
8.2 Automatic sampler . 22
8.3 Manual sampling equipment . 23
8.4 Tank sampling equipment . 24
9 Homogenization, preservation, transport and storage of samples . 24
9.1 Homogenization of collected volume . 24
9.2 Distribution of collected volume into laboratory bottles . 25
9.3 Preservation and packaging of samples . 26
9.4 Transportation and reception . 26
9.5 Security and traceability of samples during storage and delivery . 27
10 Quality assurance . 27
10.1 Avoidance of contamination . 27
10.2 Sample identification and records . 28
10.3 Assurance and quality control . 28
11 Reports . 28
11.1 Analytical reports . 28
11.2 Sampling protocols . 29
12 Safety precautions . 29
12.1 General . 29
12.2 Personnel safety . 30
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ISO/DIS 5667-10:2019(E)
12.3 Equipment safety . 30
(informative) Nuclear section — Sampling of liquid radioactive effluents . 32
Annex B (informative) Advantages and disadvantages of main types of waste water
sampling . 35
Annex C (informative) Example of cleaning protocol — Sampling equipment . 38
C.1 General . 38
C.2 Conditions of realisation . 38
C.3 Methodology . 39
Annex D (informative) Example of field form — Waste water sampling . 41
Annex E (informative) Choice of compatible materials for automatic samplers . 43
E.1 Parameters — Macro‐pollutants . 43
E.2 Micropollutants (e.g. priority hazardous substances, priority substances, emerging
substances) . 43
E.3 Synthesis of materials . 43
Annex F (informative) Comparison of types of pumping: peristaltic pump (PP) and vacuum
pump (VAP) . 45
Annex G (informative) Type of distribution of collected volume into laboratory bottle . 47
Annex H (informative) Quality control of sampling equipment . 49
H.1 General . 49
H.2 Quality Control for composite automatic sampling . 49
Bibliography . 51


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ISO/DIS 5667-10:2019(E)

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. Each 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, governmental 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 procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www.iso.org/patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation on the meaning of ISO specific terms and expressions related to conformity
assessment, as well as information about ISO's adherence to the World Trade Organization (WTO)
principles in the Technical Barriers to Trade (TBT) see the following URL:
www.iso.org/iso/foreword.html.
The committee responsible for this document is ISO/TC 147/SC 6.
This second edition cancels and replaces the first edition (ISO 5667‐10:1992), which has been
technically revised.
A list of all parts in the ISO 5667 series can be found on the ISO website.
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ISO/DIS 5667-10:2019(E)
Water quality — Sampling — Part 10: Guidance on sampling
waste water
1 Scope
This document contains details on the sampling of domestic and industrial waste water, i.e. the design of
sampling programmes and techniques for the collection of samples. It covers waste water in all its
forms, i.e. industrial waste water, radioactive waste water, cooling water, raw and treated domestic
waste water.
It deals with various sampling techniques used and the rules to be applied so as to ensure the samples
are representative.
Sampling of accidental spillages is not included, although the methods described in certain cases
may also be applicable to spillages.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated
references, only the edition cited applies. For undated references, the latest edition of the referenced
document (including any amendments) applies.
ISO 5667‐1, Water quality — Sampling — Part 1: Guidance on the design of sampling programmes and
sampling techniques
ISO 5667‐3, Water quality — Sampling — Part 3: Preservation and handling of water samples
ISO 5667‐14, Water quality — Sampling — Part 14: Guidance on quality assurance and quality control of
environmental water sampling and handling
ISO 5667‐16, Water quality — Sampling — Part 16: guidance on biotesting of samples
ISO 19458, Water quality — Sampling for microbiological analysis
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.

ISO and IEC maintain terminological databases for use in standardization, in particular all the
terminology of the ISO 6107 series (Water Quality ‐ Vocabulary), at the following addresses:
— ISO Online browsing platform: available at http://www.iso.org/obp
— IEC Electropedia: available at http://www.electropedia.org/
3.1
composite sample
two or more samples or sub‐samples, mixed together in appropriately known proportions (either
discretely or continuously), from which the average value of a desired characteristic may be obtained
Note to entry: The number of samples or sub samples are usually based on time, flow measurements, area or
depth profile sampling.
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Composite sample can be made in different ways:
- constant volume variable time sampling (C.V.V.T): flow proportional sampling based on
collecting equal volumes of sample at frequencies proportional to flow
- constant time variable volume sampling (C.T.V.V): flow proportional sampling based on
collecting samples at fixed time intervals but where the volume of sample is varied in
proportion to the flow
- constant time constant volume sampling (C.T.C.V): equal volumes of sample or sub‐sample
collected at equal increments of time
3.2
sampling point
precise position within a sampling location from which samples are taken
3.3
spot sample
discrete sample taken randomly (with regard to time and/or location) from a body of water. Spot
samples are usually taken manually, but may be taken by automatic sampling equipment or by event‐
triggered automatic samplers
3.4
qualified spot sample
special form of a composite sample, consisting of at least five spot samples, taken and mixed within a
maximum period of two hours and at an interval of not less than two minutes
3.5
radioactive liquid effluent
water or waste water that contains radioactive substances, resulting from a process and that can be
recycled, treated and/or discharged to the environment
Note to entry: The activity concentration of the radioactive liquid effluent is usually measured before being
discharged in the environment to verify that it is lower than the authorized levels in order to comply with national
regulation
3.6
supernatant
solid or liquid phase present on the surface of an effluent
3.7
planned discharge
discharge subject to prior agreement further to a consultation between several parties based on
knowing certain predefined parameters and referring to limit values (regulatory or otherwise)
Note to entry: These parameters may, for example, be physicalchemical and radiological measurements, the
estimated discharge volume, the discharge period or the maximum discharge flow rate
3.8
permanent discharge
direct discharge into a channel or collector or water body, which is not subject to a specific prior
agreement, but which shall comply with limit values
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ISO/DIS 5667-10:2019(E)
3.9
tank
hollow object, very variable in size, used to hold liquids. Covers the usual names such as tank, chamber
and pool. The content of this tank is intended for direct and indirect liquid discharge to the environment
or to a specific treatment
3.10
event‐trigged sampling
sampling which is triggered because a pre‐determined criterion has been met (e.g. rainfall, change in
electrical conductivity, pH or the introduction of a polluting substance), when samples should be taken
manually or by automatic equipment
4 General aspects
4.1 Design of sampling programme
Sampling is usually the first step in carrying out an investigation and largely determines the quality of
the whole investigation. It is therefore recommended that a detailed sampling strategy be drawn up,
often based upon a preliminary investigation in which an assessment has identified the important
aspects. Both the purpose and the ambient situation determine the way in which the sampling is carried
out. General aspects for sampling programme design can be found in ISO 5667‐1.
4.2 Sampling point selection ‐ Representativeness
The sampling point selection should be representative of the waste stream to be examined. In some
waste waters this representativeness may be difficult to obtain because of the spatial and temporal
heterogeneity of the water body. It is necessary to carry out the sampling in the sections where the flow
is well mixed and homogeneous.
The term “representativeness” encompasses two notions depending on the type of environment to be
sampled:

— representativeness in a flow (canal, sewer, manhole, pressurised pipes, etc.);
— representativeness in a storage (tank, lagoons, basins, etc.).

These two notions should be treated in different ways, but the goal remains to obtain a representative
sample of the water body.
Sampling points may be clearly identified (by regulatory text) or not, in which case a preliminary
investigation is recommended. This is generally the case for the selection of sewer sampling locations.
By studying drawings of the sewer system initially, possible locations can be identified. Subsequently, a
site inspectionshould be conducted to ensure that the locations of the sewers and the path of the waste
stream corresponds to the drawings, and to make sure that the selected location is representative for
the sampling purpose. The tracer studies may be a helpful tool.
Each sampling point should be documented. It is important to gather, for example, the following
information: identification, location of the site, photos, geographical coordinates, site location, type of
flow (open, closed), access conditions and sampling technique.
If necessary, specifically describe and label the sampling site. Select the site so that representative
samples can be obtained and the waste water flow (with the exception of fixed sampling equipment) is
clearly visible from the sampling site.
The following facilities should be available for the fixed sampling sites:
— access for motor vehicles to the immediate vicinity of the sampling site;
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— flat working surfaces and allowable height above the sampling point for the set‐up of sampling
devices;
— adequate lighting and power connection;
— water connection to clean the equipment after sampling;
— adequate safety precautions (e.g. grids, railings, fall arresting devices); and
— flow meters in the case of a flow‐dependent sampling.
If the hydraulic conditions do not guarantee the representativeness of the sample (absence of flow,
reduced activity, abnormal load rise), a sample should not be taken, and the client and the analytical
laboratory informed. If the sampling is performed, this unusual situation should be noted on the
sampling report.
4.3 Frequency and time of sampling
4.3.1 Number of samples
Analyses should be based on samples taken at regular intervals during a certain period (i.e. the
sampling period). The samples should be composite samples, unless the determinands to be analysed
prohibit the use of a composite sample. The decision on the required number of samples taken during
each period should be decided based on statistical techniques (see ISO 2602 [1], ISO 3534 [2] and ISO
5667‐1). But the number of samples to be taken may often be decided by the regulatory body or
pollution control authorities.
4.3.2 Sampling time for effluent stream
The objective of a sampling programme often dictates when and how a sample is collected and is often
determined by legislation or directives. Generally, when sampling sewages and effluents, it is normal to
make allowances for the following sources of variation in quality:
a) diurnal variations (i.e. within‐day variability);
b) variations between days of the week;
c) variations between weeks and months;
d) variations between seasons;
e) variations due to storm water episodes; and
f) trends.

If there is little or no diurnal variation, or day‐to‐day variations, then the particular time of day or day of
the week for sampling is relatively unimportant.
If the identification of the nature and magnitude of peak load are important, sampling should be
restricted to those periods of the day, week or month when peak loads are known to occur.
Relating the times of sampling to the particular process being monitored may be very important when
considering industrial effluent discharges that are either seasonal or operated on a batch basis. In either
case, the discharge will not be continuous, and the sampling programme will need to take this fact into
account.
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Sampling for the detection of trends needs careful planning. For example, when detecting trends on
month‐to‐month basis, it is appropriate to always sample on the same day of the week, in order
a
that any diurnal and daily variations are eliminated from the overall variability of data, thus allowing
trends to be more efficiently detected.
When the number of samples has been decided upon according to 4.3.1, the sampling times should
be determined. The samples should normally be taken at fixed intervals during the whole control
period. The sampling period may be one year, a number of months or weeks, or even shorter periods
of time.
If the sampling period covers one year, the days of sampling may be determined using a formula.
An example of this is:
Formula (1) for a number of samples (n), larger than about 25 and from formula (2) for a number of
samples less than about 25.
Formula (1) indicates the day number during which sampling should take place.
365 3652 365 3 365n
AA, ,A ,.,A (1)
nn n n
where
n is the number of samples;
365
A is a random number in the interval between  and 0.
n
Formula (2) indicates the week number during which the sampling should take place. The day of each
week should be determined so that samples are taken on every weekday.

52 522 52 3 52n
BB, ,B ,.,B (2)
nn n n
where
n is the number of samples;
52
B is a random number in the interval between  and 0.
n
Similar formulae can be used for other periods, for example, one month, three months, six months, etc.
variations.
The period chosen should cover any seasonal
After determining the intervals and the day or week number, it should be ensured that the sampling
does not lead to any risk of systematic error, for example by always taking samples on one day, or by
systematically omitting weekdays.
5 Sampling at specific locations
The concentration profiles of dissolved substances and suspended solids measured in an effluent
are often heterogeneous because they depend on the hydraulic conditions and transport
conditions of the solid phase in the body of water. Observations are:
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— A vertical gradient of concentration, due to the flow velocities or the shear stresses near the
bottom are low;
— A very dense layer at the interface between the deposit of the bottom and the water circulating
in the structure;
— An increase of the concentration near the walls;
— An increase of the concentration near the surface of the flow due to the presence of floating
matter.
It is therefore necessary to define carefully the positioning of the sample taken within the body of
water. To take a sample theoretically representative of the average concentration of the measured
section, it is advisable to place the sampling point about halfway up the water column and at a
sufficient distance from the walls and deposits to avoid measurement bias.
5.1 Sampling from sewers, channels and manholes
A location should be chosen where the effluent has a high turbulent flow to ensure good mixing. Often
accessibility, lack of site security, or power unavailability may preclude the use of the best sites.
Since effluent channels are generally designed to cope with both effluent and storm‐water discharge
conditions and/or for higher flows than those actually occurring, laminar flow may often occur. In the
absence of a location with turbulent flow conditions, such conditions should be induced by restricting
the flow, for example with a baffle or weir. The restriction should be made in such a way that
sedimentation upstream of the restriction does not occur (e.g. foresee enlargement of the downstream
effluent channel compared to the upstream channel, to avoid any pressure increase of the effluent
downstream).
The sampling intake point should always be located downstream from the restriction and, as a general
rule, it should be located at least three times the pipe diameter, or width of the channel, downstream of
the restriction. The inlet of the sa
...