SIST ISO 5667-24:2018

SLOVENSKI STANDARD
SIST ISO 5667-24:2018
01-september-2018
.DNRYRVWYRGH9]RUþHQMHGHO1DYRGLOR]DSUHVRMRNDNRYRVWLY]RUþHQMDYRGH
Water quality - Sampling - Part 24: Guidance on the auditing of water quality sampling
Qualité de l'eau - Échantillonnage - Partie 24: Lignes directrices pour l'audit de
l'échantillonnage de la qualité de l'eau
Ta slovenski standard je istoveten z: ISO 5667-24:2016
ICS:
13.060.10 Voda iz naravnih virov Water of natural resources
13.060.45 Preiskava vode na splošno Examination of water in
general
SIST ISO 5667-24:2018 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST ISO 5667-24:2018

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SIST ISO 5667-24:2018
INTERNATIONAL ISO
STANDARD 5667-24
First edition
2016-04-01
Water quality — Sampling —
Part 24:
Guidance on the auditing of water
quality sampling
Qualité de l’eau — Échantillonnage —
Partie 24: Lignes directrices pour l’audit de l’échantillonnage de la
qualité de l’eau
Reference number
ISO 5667-24:2016(E)
©
ISO 2016

---------------------- Page: 3 ----------------------

SIST ISO 5667-24:2018
ISO 5667-24:2016(E)

COPYRIGHT PROTECTED DOCUMENT
© ISO 2016, Published in Switzerland
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
ii © ISO 2016 – All rights reserved

---------------------- Page: 4 ----------------------

SIST ISO 5667-24:2018
ISO 5667-24:2016(E)

Contents Page
Foreword .v
Introduction .vii
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Multiple audits . 4
5 Auditing objectives . 5
6 Internal audit objectives . 6
7 External audit objectives . 6
8 Identification of the critical factors in the water quality sampling process.6
8.1 Identification of critical operational steps . 6
8.2 Audit prioritization exercise . 7
8.3 Unscheduled observations. 7
8.4 Follow-up actions. 8
9 Risk-based versus judgement-based approaches to auditing . 8
9.1 General . 8
9.2 Risk-based auditing. 8
9.3 Judgement-based auditing . 9
9.4 Auditing assumptions . 9
10 Document auditing . 9
10.1 Sampling programme and sampling practitioner/operative instruction documents . 9
10.2 Sampling manual . 9
10.2.1 General. 9
10.2.2 Contents . .10
10.2.3 Format .11
10.2.4 The laboratory interface.12
10.3 Training policy .13
10.4 Sampling record sheets .13
10.5 Labels .13
10.6 Chain of custody records .14
10.7 Laboratory receipts .15
10.8 Assessment of documents before the field assessment.15
10.9 Assessment of completed documents .15
10.10 Policy on statements of uncertainty .16
11 Real-time audit .16
11.1 Audit forms .16
11.2 Field observation .16
11.3 Real-time risk-based auditing (see also 9.2) .17
11.4 Real-time judgement-based auditing (see also 9.3) .17
11.5 Evidence of internal audits .17
12 Design of an audit plan.17
12.1 Consultation with the responsible person .17
12.2 Pre-audit questionnaire .17
12.3 Plan design .18
12.4 Audit practice .18
12.4.1 Staff competence assessments.18
12.4.2 Supervision .18
12.4.3 Equipment .19
12.4.4 Handling of samples . .19
© ISO 2016 – All rights reserved iii

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SIST ISO 5667-24:2018
ISO 5667-24:2016(E)

12.4.5 Individual sample records .19
12.4.6 Tracking of samples .20
12.5 Quality assurance and control issues (see ISO 5667-14) .20
13 Conduct of field assessments .20
13.1 General .20
13.2 Sample location verification .21
13.3 Identification .22
13.4 The use of photographs in field assessment.22
14 Audit methodology .22
14.1 General .22
14.2 Conduct of the audit .22
14.3 Reviewing the audit plan .23
14.4 Real-time assessment .24
14.4.1 General.24
14.4.2 Pre-audit meeting .24
14.4.3 Opening meeting .24
14.4.4 Traceability assessments before real-time audit .24
14.4.5 Observation procedures .24
14.4.6 Assessing conformity with temperature control during the audit .25
14.4.7 Auditing of photographic evidence .25
14.4.8 Interpretation of audit data .26
14.4.9 Recording nonconformity .26
15 Assignment of the audit report and the closure meeting .26
16 The audit report and statement of findings .27
16.1 The report .27
16.2 Statement of findings . .28
16.3 Audit conclusions .28
16.4 Statement of recommended actions .28
17 Outline flow diagram of audit process .30
Annex A (informative) Audit forms .32
Annex B (informative) Suggested procedures for monitoring temperature control .95
Annex C (informative) Measurement of uncertainty associated with sampling practices .96
Bibliography .97
iv © ISO 2016 – All rights reserved

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SIST ISO 5667-24:2018
ISO 5667-24:2016(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 WTO principles in the Technical
Barriers to Trade (TBT) see the following URL: Foreword - Supplementary information
The committee responsible for this document is ISO/TC 147, Water quality, Subcommittee SC 6, Sampling
(general methods).
ISO 5667 consists of the following parts, under the general title Water quality — Sampling:
— Part 1: Guidance on the design of sampling programmes and sampling techniques
— Part 3: Preservation and handling of water samples
— Part 4: Guidance on sampling from lakes, natural and man-made
— Part 5: Guidance on sampling of drinking water from treatment works and piped distribution systems
— Part 6: Guidance on sampling of rivers and streams
— Part 7: Guidance on sampling of water and steam in boiler plants
— Part 8: Guidance on the sampling of wet deposition
— Part 9: Guidance on sampling from marine waters
— Part 10: Guidance on sampling of waste waters
— Part 11: Guidance on sampling of groundwaters
— Part 12: Guidance on sampling of bottom sediments
— Part 13: Guidance on sampling of sludges
— Part 14: Guidance on quality assurance and quality control of environmental water sampling and handling
— Part 15: Guidance on the preservation and handling of sludge and sediment samples
— Part 16: Guidance on biotesting of samples
— Part 17: Guidance on sampling of bulk suspended solids
© ISO 2016 – All rights reserved v

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SIST ISO 5667-24:2018
ISO 5667-24:2016(E)

— Part 19: Guidance on sampling of marine sediments
— Part 20: Guidance on the use of sampling data for decision making — Compliance with thresholds and
classification systems
— Part 21: Guidance on sampling of drinking water distributed by tankers or means other than
distribution pipes
— Part 22: Guidance on the design and installation of groundwater monitoring points
— Part 23: Guidance on passive sampling in surface water
— Part 24: Guidance on the auditing of water quality sampling
vi © ISO 2016 – All rights reserved

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SIST ISO 5667-24:2018
ISO 5667-24:2016(E)

Introduction
The sampling and analysis of drinking water supplies is one of the key elements in the protection of
public health. Environmental sampling from rivers and other surface waters; sampling of discharges
such as treated sewage effluents and trade discharges; and sampling of water used for non-potable
purposes can also have a significant impact on public health, occupational hygiene and asset durability.
One of the major sources of error in gathering water quality monitoring data can be the sampling
process. Poor sampling practices create problems for those interpreting results and can lead to costly
and incorrect decisions. Failure to manage factors such as Cryptosporidium levels in drinking water,
pneumonia caused by Legionella and heating system corrosion are examples of where failures of quality
control/assurance in the sampling process can lead to expensive and potentially life-threatening
consequences.
Auditing of water quality sampling identifies both positive and negative attributes of the management
chain. Thus, the goal of a sampling audit is to emphasize the effectiveness of “best practice” and to build
up a knowledge base to allow its dissemination within the organization.
No audit is ever intended to cover every aspect of water quality sampling and it is advisable to adopt
a risk-based approach to designing the audit programme to ensure that high-risk issues are covered
more frequently, and in greater depth, than low-risk issues. For example, it is essential that all high-level
documentation, which covers sampling policy and strategy, training policy and health and safety policy,
is checked during the first audit, along with its implementation on the ground. Where implementation
documents are also produced at a high-level (sampling manuals, training manuals, etc.) they might be
regarded as high-level documents for the purpose of designing the audit programme. Providing there
are no issues arising, this documentation would only need detailed checking on subsequent audits if
any changes have been made during the interim. However, it would still be prudent to check that any
issues identified during the initial audit have been addressed satisfactorily; that any other changes are
appropriate; and that the circumstances of sampling have not changed in such a way that a revision of
these high-level documents is needed.
Larger organizations might wish to either audit fully high-level documentation at regular interims
(e.g. every four years) or to audit different parts of the documentation on a rolling programme. They
might also wish to consider a regular programme of auditing the dissemination of changes to high-level
documentation as these could take time to work their way down to the sampling practitioners/operatives
and their managers, especially where there is a large geographical spread and sampling is not the main
function. This is rarely a problem in small organizations where the person responsible for writing the
high-level documents is usually also responsible for managing, if not carrying out, the sampling.
Risks of nonconformity at sampling locations can vary markedly, and the frequency and extent of each
audit needs to reflect this. Some organizations sample only in very closely controlled environments,
where purpose-built sampling taps are provided. Here the risk of nonconformity is very low, but, at
the same time, a very high degree of conformity can be expected. Other organizations take samples in
environments which vary and which are often far from ideal, making compromise necessary. The audit
might identify a number of risks of nonconformity with the documented procedures, but allowances
have to be made for any guidance given to the sampling practitioner/operative and the process by
which a satisfactory compromise is reached and recorded.
The key point in designing an audit programme is to ensure that the effort spent on auditing is
proportional to the risk and the size of the organization. The programme is therefore refined in the
light of experience.
© ISO 2016 – All rights reserved vii

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SIST ISO 5667-24:2018

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SIST ISO 5667-24:2018
INTERNATIONAL STANDARD ISO 5667-24:2016(E)
Water quality — Sampling —
Part 24:
Guidance on the auditing of water quality sampling
IMPORTANT — It has been assumed in the preparation of this International Standard that the
execution of its provisions will be entrusted to appropriately qualified and experienced people,
for whose use it has been produced.
1 Scope
This part of ISO 5667 provides an audit protocol to monitor conformity with declared, or assumed,
practices in all areas of water quality sampling. Specifically, this part of ISO 5667 provides guidance on
the systematic assessment of sampling practices and procedures in the field, and assessing conformity
with those given in the organization’s sampling manual. It is applicable to the audit of sampling activities
from the development of a sampling manual through to the delivery of samples to the laboratory.
NOTE 1 The design of the sampling manual is the prerogative of the data user and this part of ISO 5667 is not
intended to deliver criticism of a manual’s structure.
This part of ISO 5667 is applicable to sampling practices associated with wastewaters, including
discharges to water bodies, environmental monitoring, potable water supplies from source to tap,
commercial and industrial uses of water, and power generation.
This part of ISO 5667 is applicable to the auditing of sampling practices relevant to the management
of water stored in containers, such as temporary supply tanks and bottled supplies. However, it is not
applicable for the auditing (or calibration and maintenance) of on-site test equipment or kits.
NOTE 2 BS 1427 covers water test kits used “in the field”.
The following sampling occasions are excluded from both the field- and desk-audit procedures set out
in this part of ISO 5667:
a) chemical and microbiological incidents, which are investigated by agencies such as the emergency
services, e.g. where an immediate risk to the health of the sampling practitioner/operative is evident;
b) radiochemical sampling of water quality, other than that specified as a routine requirement under
[9][10][11][12]
the UK Water Supply (Water Quality) Regulations, i.e. radiochemical incidents which
are investigated by agencies such as the emergency services.
Informative Annex A contains a series of forms to assist with auditing. These are for guidance only.
Informative Annex B gives procedures for monitoring temperature control, while Informative Annex C
provides guidance on measuring the uncertainty associated with sampling practices.
2 Normative references
There are no normative references cited in the document.
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
© ISO 2016 – All rights reserved 1

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SIST ISO 5667-24:2018
ISO 5667-24:2016(E)

3.1
audit
formal examination of the organization’s processes and procedures as a means of identifying critical
operational risk to sample and data integrity generated during the collection of samples
Note 1 to entry: ISO 19011 can be used for auditing of sampling.
Note 2 to entry: ISO/IEC 17025:2005, 5.7, introduces specific requirements for sampling.
3.2
audit conclusion
overall conclusion of the impact of water quality sampling practice on data quality
Note 1 to entry: Such a statement can be judgemental rather than based on any statistical consideration, and
depends on the audit plan.
3.3
audit coordinator
member of the audit team nominated to liaise with the responsible person and to coordinate the overall
audit process where an audit involves more than one auditor
3.4
audit detection risk
probability that the audit will not identify a nonconformity during the period of assessment
Note 1 to entry: BS 4778–3.1:1991 defines risk as a “combination of the probability, or frequency, of occurrence
of a defined hazard and the magnitude of the consequences of the occurrence.” A mathematical interpretation of
this definition is risk = hazard × probability of the hazard happening.
3.5
auditor
person who undertakes an audit of the organization’s documented water quality sampling practices
and procedures and reports on conformity to these
Note 1 to entry: Ideally, the auditor will have operational experie
...

SLOVENSKI STANDARD
oSIST ISO 5667-24:2018
01-junij-2018
.DNRYRVWYRGH9]RUþHQMHGHO1DYRGLOR]DSUHVRMRNDNRYRVWLY]RUþHQMDYRGH
Water quality - Sampling - Part 24: Guidance on the auditing of water quality sampling
Qualité de l'eau - Échantillonnage - Partie 24: Lignes directrices pour l'audit de
l'échantillonnage de la qualité de l'eau
Ta slovenski standard je istoveten z: ISO 5667-24:2016
ICS:
13.060.10 Voda iz naravnih virov Water of natural resources
13.060.45 Preiskava vode na splošno Examination of water in
general
oSIST ISO 5667-24:2018 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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oSIST ISO 5667-24:2018

---------------------- Page: 2 ----------------------
oSIST ISO 5667-24:2018
INTERNATIONAL ISO
STANDARD 5667-24
First edition
2016-04-01
Water quality — Sampling —
Part 24:
Guidance on the auditing of water
quality sampling
Qualité de l’eau — Échantillonnage —
Partie 24: Lignes directrices pour l’audit de l’échantillonnage de la
qualité de l’eau
Reference number
ISO 5667-24:2016(E)
©
ISO 2016

---------------------- Page: 3 ----------------------
oSIST ISO 5667-24:2018
ISO 5667-24:2016(E)

COPYRIGHT PROTECTED DOCUMENT
© ISO 2016, Published in Switzerland
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
ii © ISO 2016 – All rights reserved

---------------------- Page: 4 ----------------------
oSIST ISO 5667-24:2018
ISO 5667-24:2016(E)

Contents Page
Foreword .v
Introduction .vii
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Multiple audits . 4
5 Auditing objectives . 5
6 Internal audit objectives . 6
7 External audit objectives . 6
8 Identification of the critical factors in the water quality sampling process.6
8.1 Identification of critical operational steps . 6
8.2 Audit prioritization exercise . 7
8.3 Unscheduled observations. 7
8.4 Follow-up actions. 8
9 Risk-based versus judgement-based approaches to auditing . 8
9.1 General . 8
9.2 Risk-based auditing. 8
9.3 Judgement-based auditing . 9
9.4 Auditing assumptions . 9
10 Document auditing . 9
10.1 Sampling programme and sampling practitioner/operative instruction documents . 9
10.2 Sampling manual . 9
10.2.1 General. 9
10.2.2 Contents . .10
10.2.3 Format .11
10.2.4 The laboratory interface.12
10.3 Training policy .13
10.4 Sampling record sheets .13
10.5 Labels .13
10.6 Chain of custody records .14
10.7 Laboratory receipts .15
10.8 Assessment of documents before the field assessment.15
10.9 Assessment of completed documents .15
10.10 Policy on statements of uncertainty .16
11 Real-time audit .16
11.1 Audit forms .16
11.2 Field observation .16
11.3 Real-time risk-based auditing (see also 9.2) .17
11.4 Real-time judgement-based auditing (see also 9.3) .17
11.5 Evidence of internal audits .17
12 Design of an audit plan.17
12.1 Consultation with the responsible person .17
12.2 Pre-audit questionnaire .17
12.3 Plan design .18
12.4 Audit practice .18
12.4.1 Staff competence assessments.18
12.4.2 Supervision .18
12.4.3 Equipment .19
12.4.4 Handling of samples . .19
© ISO 2016 – All rights reserved iii

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oSIST ISO 5667-24:2018
ISO 5667-24:2016(E)

12.4.5 Individual sample records .19
12.4.6 Tracking of samples .20
12.5 Quality assurance and control issues (see ISO 5667-14) .20
13 Conduct of field assessments .20
13.1 General .20
13.2 Sample location verification .21
13.3 Identification .22
13.4 The use of photographs in field assessment.22
14 Audit methodology .22
14.1 General .22
14.2 Conduct of the audit .22
14.3 Reviewing the audit plan .23
14.4 Real-time assessment .24
14.4.1 General.24
14.4.2 Pre-audit meeting .24
14.4.3 Opening meeting .24
14.4.4 Traceability assessments before real-time audit .24
14.4.5 Observation procedures .24
14.4.6 Assessing conformity with temperature control during the audit .25
14.4.7 Auditing of photographic evidence .25
14.4.8 Interpretation of audit data .26
14.4.9 Recording nonconformity .26
15 Assignment of the audit report and the closure meeting .26
16 The audit report and statement of findings .27
16.1 The report .27
16.2 Statement of findings . .28
16.3 Audit conclusions .28
16.4 Statement of recommended actions .28
17 Outline flow diagram of audit process .30
Annex A (informative) Audit forms .32
Annex B (informative) Suggested procedures for monitoring temperature control .95
Annex C (informative) Measurement of uncertainty associated with sampling practices .96
Bibliography .97
iv © ISO 2016 – All rights reserved

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oSIST ISO 5667-24:2018
ISO 5667-24:2016(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 WTO principles in the Technical
Barriers to Trade (TBT) see the following URL: Foreword - Supplementary information
The committee responsible for this document is ISO/TC 147, Water quality, Subcommittee SC 6, Sampling
(general methods).
ISO 5667 consists of the following parts, under the general title Water quality — Sampling:
— Part 1: Guidance on the design of sampling programmes and sampling techniques
— Part 3: Preservation and handling of water samples
— Part 4: Guidance on sampling from lakes, natural and man-made
— Part 5: Guidance on sampling of drinking water from treatment works and piped distribution systems
— Part 6: Guidance on sampling of rivers and streams
— Part 7: Guidance on sampling of water and steam in boiler plants
— Part 8: Guidance on the sampling of wet deposition
— Part 9: Guidance on sampling from marine waters
— Part 10: Guidance on sampling of waste waters
— Part 11: Guidance on sampling of groundwaters
— Part 12: Guidance on sampling of bottom sediments
— Part 13: Guidance on sampling of sludges
— Part 14: Guidance on quality assurance and quality control of environmental water sampling and handling
— Part 15: Guidance on the preservation and handling of sludge and sediment samples
— Part 16: Guidance on biotesting of samples
— Part 17: Guidance on sampling of bulk suspended solids
© ISO 2016 – All rights reserved v

---------------------- Page: 7 ----------------------
oSIST ISO 5667-24:2018
ISO 5667-24:2016(E)

— Part 19: Guidance on sampling of marine sediments
— Part 20: Guidance on the use of sampling data for decision making — Compliance with thresholds and
classification systems
— Part 21: Guidance on sampling of drinking water distributed by tankers or means other than
distribution pipes
— Part 22: Guidance on the design and installation of groundwater monitoring points
— Part 23: Guidance on passive sampling in surface water
— Part 24: Guidance on the auditing of water quality sampling
vi © ISO 2016 – All rights reserved

---------------------- Page: 8 ----------------------
oSIST ISO 5667-24:2018
ISO 5667-24:2016(E)

Introduction
The sampling and analysis of drinking water supplies is one of the key elements in the protection of
public health. Environmental sampling from rivers and other surface waters; sampling of discharges
such as treated sewage effluents and trade discharges; and sampling of water used for non-potable
purposes can also have a significant impact on public health, occupational hygiene and asset durability.
One of the major sources of error in gathering water quality monitoring data can be the sampling
process. Poor sampling practices create problems for those interpreting results and can lead to costly
and incorrect decisions. Failure to manage factors such as Cryptosporidium levels in drinking water,
pneumonia caused by Legionella and heating system corrosion are examples of where failures of quality
control/assurance in the sampling process can lead to expensive and potentially life-threatening
consequences.
Auditing of water quality sampling identifies both positive and negative attributes of the management
chain. Thus, the goal of a sampling audit is to emphasize the effectiveness of “best practice” and to build
up a knowledge base to allow its dissemination within the organization.
No audit is ever intended to cover every aspect of water quality sampling and it is advisable to adopt
a risk-based approach to designing the audit programme to ensure that high-risk issues are covered
more frequently, and in greater depth, than low-risk issues. For example, it is essential that all high-level
documentation, which covers sampling policy and strategy, training policy and health and safety policy,
is checked during the first audit, along with its implementation on the ground. Where implementation
documents are also produced at a high-level (sampling manuals, training manuals, etc.) they might be
regarded as high-level documents for the purpose of designing the audit programme. Providing there
are no issues arising, this documentation would only need detailed checking on subsequent audits if
any changes have been made during the interim. However, it would still be prudent to check that any
issues identified during the initial audit have been addressed satisfactorily; that any other changes are
appropriate; and that the circumstances of sampling have not changed in such a way that a revision of
these high-level documents is needed.
Larger organizations might wish to either audit fully high-level documentation at regular interims
(e.g. every four years) or to audit different parts of the documentation on a rolling programme. They
might also wish to consider a regular programme of auditing the dissemination of changes to high-level
documentation as these could take time to work their way down to the sampling practitioners/operatives
and their managers, especially where there is a large geographical spread and sampling is not the main
function. This is rarely a problem in small organizations where the person responsible for writing the
high-level documents is usually also responsible for managing, if not carrying out, the sampling.
Risks of nonconformity at sampling locations can vary markedly, and the frequency and extent of each
audit needs to reflect this. Some organizations sample only in very closely controlled environments,
where purpose-built sampling taps are provided. Here the risk of nonconformity is very low, but, at
the same time, a very high degree of conformity can be expected. Other organizations take samples in
environments which vary and which are often far from ideal, making compromise necessary. The audit
might identify a number of risks of nonconformity with the documented procedures, but allowances
have to be made for any guidance given to the sampling practitioner/operative and the process by
which a satisfactory compromise is reached and recorded.
The key point in designing an audit programme is to ensure that the effort spent on auditing is
proportional to the risk and the size of the organization. The programme is therefore refined in the
light of experience.
© ISO 2016 – All rights reserved vii

---------------------- Page: 9 ----------------------
oSIST ISO 5667-24:2018

---------------------- Page: 10 ----------------------
oSIST ISO 5667-24:2018
INTERNATIONAL STANDARD ISO 5667-24:2016(E)
Water quality — Sampling —
Part 24:
Guidance on the auditing of water quality sampling
IMPORTANT — It has been assumed in the preparation of this International Standard that the
execution of its provisions will be entrusted to appropriately qualified and experienced people,
for whose use it has been produced.
1 Scope
This part of ISO 5667 provides an audit protocol to monitor conformity with declared, or assumed,
practices in all areas of water quality sampling. Specifically, this part of ISO 5667 provides guidance on
the systematic assessment of sampling practices and procedures in the field, and assessing conformity
with those given in the organization’s sampling manual. It is applicable to the audit of sampling activities
from the development of a sampling manual through to the delivery of samples to the laboratory.
NOTE 1 The design of the sampling manual is the prerogative of the data user and this part of ISO 5667 is not
intended to deliver criticism of a manual’s structure.
This part of ISO 5667 is applicable to sampling practices associated with wastewaters, including
discharges to water bodies, environmental monitoring, potable water supplies from source to tap,
commercial and industrial uses of water, and power generation.
This part of ISO 5667 is applicable to the auditing of sampling practices relevant to the management
of water stored in containers, such as temporary supply tanks and bottled supplies. However, it is not
applicable for the auditing (or calibration and maintenance) of on-site test equipment or kits.
NOTE 2 BS 1427 covers water test kits used “in the field”.
The following sampling occasions are excluded from both the field- and desk-audit procedures set out
in this part of ISO 5667:
a) chemical and microbiological incidents, which are investigated by agencies such as the emergency
services, e.g. where an immediate risk to the health of the sampling practitioner/operative is evident;
b) radiochemical sampling of water quality, other than that specified as a routine requirement under
[9][10][11][12]
the UK Water Supply (Water Quality) Regulations, i.e. radiochemical incidents which
are investigated by agencies such as the emergency services.
Informative Annex A contains a series of forms to assist with auditing. These are for guidance only.
Informative Annex B gives procedures for monitoring temperature control, while Informative Annex C
provides guidance on measuring the uncertainty associated with sampling practices.
2 Normative references
There are no normative references cited in the document.
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
© ISO 2016 – All rights reserved 1

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oSIST ISO 5667-24:2018
ISO 5667-24:2016(E)

3.1
audit
formal examination of the organization’s processes and procedures as a means of identifying critical
operational risk to sample and data integrity generated during the collection of samples
Note 1 to entry: ISO 19011 can be used for auditing of sampling.
Note 2 to entry: ISO/IEC 17025:2005, 5.7, introduces specific requirements for sampling.
3.2
audit conclusion
overall conclusion of the impact of water quality sampling practice on data quality
Note 1 to entry: Such a statement can be judgemental rather than based on any statistical consideration, and
depends on the audit plan.
3.3
audit coordinator
member of the audit team nominated to liaise with the responsible person and to coordinate the overall
audit process where an audit involves more than one auditor
3.4
audit detection risk
probability that the audit will not identify a nonconformity during the period of assessment
Note 1 to entry: BS 4778–3.1:1991 defines risk as a “combination of the probability, or frequency, of occurrence
of a defined hazard and the magnitude of the consequences of the occurrence.” A mathematical interpretation of
this definition is risk = hazard × probability of the hazard happening.
3.5
auditor
person who undertakes an audit of the organization’s documented water quality sampling practices
and procedures and reports on conformity to these
Note 1 to entry: Ideally, the auditor will have operational experience of the ty
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