SIST EN ISO 5667-3:2018

Water quality - Sampling - Part 3: Preservation and handling of water samples (ISO 5667-3:2018)

This document specifies general requirements for sampling, preservation, handling, transport and
storage of all water samples including those for biological analyses.
It is not applicable to water samples intended for microbiological analyses as specified in ISO 19458,
ecotoxicological assays, biological assays and passive sampling as specified in the scope of ISO 5667-23.
This document is particularly appropriate when spot or composite samples cannot be analysed on site
and have to be transported to a laboratory for analysis.

Wasserbeschaffenheit - Probenahme - Teil 3: Konservierung und Handhabung von Wasserproben (ISO 5667-3:2018)

Dieses Dokument legt allgemeine Anforderungen für die Probenahme, Konservierung, Handhabung, den Transport und die Lagerung aller Wasserproben einschließlich derer für biologische Untersuchungen fest.
Es ist nicht anwendbar für Wasserproben zur mikrobiologischen Untersuchung nach ISO 19458, für ökotoxikologische Tests, für biologische Tests sowie zur passiven Probenahme nach ISO 5667 23.
Dieses Dokument ist besonders für jene Proben (Einzel  oder Mischproben) geeignet, die nicht unmittelbar vor Ort untersucht werden können und hierfür in das Labor gebracht werden müssen.

Qualité de l'eau - Échantillonnage - Partie 3: Conservation et manipulation des échantillons d'eau (ISO 5667-3:2018)

Le présent document spécifie les exigences générales relatives à l'échantillonnage, la conservation, la manipulation, le transport et le stockage de tous les échantillons d'eau, y compris ceux destinés à des analyses biologiques.
Elle ne s'applique pas aux échantillons d'eau destinés à des analyses microbiologiques telles que spécifiées dans l'ISO 19458, des essais écotoxicologiques, des essais biologiques et ni à l'échantillonnage passif tel que spécifié dans le domaine d'application de l'ISO 5667‑23.
Le présent document s'applique en particulier chaque fois qu'un échantillon ponctuel ou composite ne peut être analysé sur site et doit être transporté vers un laboratoire pour analyse.

Kakovost vode - Vzorčenje - 3. del: Konzerviranje in ravnanje z vzorci vode (ISO 5667-3:2018)

Ta dokument določa splošne zahteve za vzorčenje, konzerviranje, ravnanje, prevoz in skladiščenje vseh vzorcev vode, tudi tistih za biološke analize.
Ne uporablja se za vzorce vode za mikrobiološke analize iz standarda ISO 19458 ter za ekotoksikološke preskuse, biološke preskuse in pasivno vzorčenje iz standarda ISO 5667-23.
Ta dokument je zlasti primeren, če naključnih ali sestavljenih vzorcev ni mogoče analizirati na mestu samem in jih je treba prenesti v laboratorij za analizo.

General Information

• Status: Published
• Public Enquiry End Date: 01-Apr-2018
• Publication Date: 20-Aug-2018
• ICS: 13.060.45 - Examination of water in general
• Technical Committee: KAV - Water quality
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 09-Jul-2018
• Due Date: 13-Sep-2018
• Completion Date: 21-Aug-2018
• Directive: TP020 - Pravilnik o monitoringu stanja površinskih voda
• Directive: TP027 - Pravilnik o obratovalnem monitoringu stanja površinskih voda
• Directive: TP036 - Pravilnik o obratovalnem monitoringu stanja podzemne vode
• Directive: TRRTP074 - Pravilnik o spremembah in dopolnitvah Pravilnika o monitoringu stanja površinskih voda
• Ref Project: EN ISO 5667-3:2018 - Water quality - Sampling - Part 3: Preservation and handling of water samples (ISO 5667-3:2018)

Relations

• Replaces: SIST EN ISO 5667-3:2013 - Water quality - Sampling - Part 3: Preservation and handling of water samples (ISO 5667-3:2012)
• Effective Date: 01-Sep-2018
• Replaces: SIST EN ISO 5667-3:2013 - Water quality - Sampling - Part 3: Preservation and handling of water samples (ISO 5667-3:2012)
• Effective Date: 08-Jun-2022

Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN ISO 5667-3:2018
01-september-2018
1DGRPHãþD
SIST EN ISO 5667-3:2013
.DNRYRVWYRGH9]RUþHQMHGHO.RQ]HUYLUDQMHLQUDYQDQMH]Y]RUFLYRGH,62


Water quality - Sampling - Part 3: Preservation and handling of water samples (ISO 5667

-3:2018)
Wasserbeschaffenheit - Probenahme - Teil 3: Konservierung und Handhabung von
Wasserproben (ISO 5667-3:2018)
Qualité de l'eau - Échantillonnage - Partie 3: Conservation et manipulation des
échantillons d'eau (ISO 5667-3:2018)
Ta slovenski standard je istoveten z: EN ISO 5667-3:2018
ICS:
13.060.45 Preiskava vode na splošno Examination of water in
general
SIST EN ISO 5667-3:2018 en,fr,de

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN ISO 5667-3:2018
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SIST EN ISO 5667-3:2018
EN ISO 5667-3
EUROPEAN STANDARD
NORME EUROPÉENNE
June 2018
EUROPÄISCHE NORM
ICS 13.060.45 Supersedes EN ISO 5667-3:2012
English Version
Water quality - Sampling - Part 3: Preservation and
handling of water samples (ISO 5667-3:2018)

Qualité de l'eau - Échantillonnage - Partie 3: Wasserbeschaffenheit - Probenahme - Teil 3:

Conservation et manipulation des échantillons d'eau Konservierung und Handhabung von Wasserproben

(ISO 5667-3:2018) (ISO 5667-3:2018)
This European Standard was approved by CEN on 9 June 2018.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this

European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references

concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN

member.

This European Standard exists in three official versions (English, French, German). A version in any other language made by

translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management

Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,

Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,

Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,

Turkey and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels

© 2018 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 5667-3:2018 E

worldwide for CEN national Members.
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SIST EN ISO 5667-3:2018
EN ISO 5667-3:2018 (E)
Contents Page

European foreword ....................................................................................................................................................... 3

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SIST EN ISO 5667-3:2018
EN ISO 5667-3:2018 (E)
European foreword

This document (EN ISO 5667-3:2018) has been prepared by Technical Committee ISO/TC 147 "Water

quality" in collaboration with Technical Committee CEN/TC 230 “Water analysis” the secretariat of

which is held by DIN.

This European Standard shall be given the status of a national standard, either by publication of an

identical text or by endorsement, at the latest by December 2018, and conflicting national standards

shall be withdrawn at the latest by December 2018.

Attention is drawn to the possibility that some of the elements of this document may be the subject of

patent rights. CEN shall not be held responsible for identifying any or all such patent rights.

This document supersedes EN ISO 5667-3:2012.

According to the CEN-CENELEC Internal Regulations, the national standards organizations of the

following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria,

Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia,

France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta,

Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,

Turkey and the United Kingdom.
Endorsement notice

The text of ISO 5667-3:2018 has been approved by CEN as EN ISO 5667-3:2018 without any

modification.
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SIST EN ISO 5667-3:2018
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SIST EN ISO 5667-3:2018
INTERNATIONAL ISO
STANDARD 5667-3
Fifth edition
2018-05
Water quality — Sampling —
Part 3:
Preservation and handling of water
samples
Qualité de l'eau — Échantillonnage —
Partie 3: Conservation et manipulation des échantillons d'eau
Reference number
ISO 5667-3:2018(E)
ISO 2018
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SIST EN ISO 5667-3:2018
ISO 5667-3:2018(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2018

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: [phone]
Fax: [phone]
Email: [e-mail]
Website: www.iso.org
Published in Switzerland
ii © ISO 2018 – All rights reserved
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SIST EN ISO 5667-3:2018
ISO 5667-3:2018(E)
Contents Page

Foreword ........................................................................................................................................................................................................................................iv

Introduction ..................................................................................................................................................................................................................................v

1 Scope ................................................................................................................................................................................................................................. 1

2 Normative references ...................................................................................................................................................................................... 1

3 Terms and definitions ..................................................................................................................................................................................... 1

4 Sampling and chain of custody .............................................................................................................................................................. 2

5 Reagents and materials ................................................................................................................................................................................. 2

6 Containers ................................................................................................................................................................................................................... 5

6.1 Container selection and preparation ................................................................................................................................... 5

6.2 Filtration on site ..................................................................................................................................................................................... 5

6.3 Filling the container ........................................................................................................................................................................... 5

7 Sample handling and preservation ................................................................................................................................................... 5

7.1 Sample handling and preservation for physical and chemical examination ..................................... 5

7.2 Sample handling and preservation for biological examination .................................................................... 6

7.3 Sample handling and preservation for radiochemical analysis .................................................................... 7

8 Sample transport ................................................................................................................................................................................................. 7

9 Identification of samples ............................................................................................................................................................................. 8

10 Sample reception ................................................................................................................................................................................................. 8

11 Sample storage ....................................................................................................................................................................................................... 8

Annex A (informative) Techniques for sample preservation ...................................................................................................10

Annex B (informative) Container preparation ........................................................................................................................................44

Annex C (informative) Protocol as used in Dutch validation studies ...............................................................................45

Bibliography .............................................................................................................................................................................................................................47

© ISO 2018 – All rights reserved iii
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SIST EN ISO 5667-3:2018
ISO 5667-3:2018(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 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 the following

URL: www .iso .org/iso/foreword .html.

This document was prepared by Technical Committee ISO/TC 147, Water quality, Subcommittee SC 6,

Sampling (general methods).

This fifth edition cancels and replaces the fourth edition (ISO 5667-3:2012), of which it constitutes a

minor revision. The changes compared to the previous edition are as follows:
— updated references in Table A.1;

— clarification in the Introduction concerning use of the preservation times and conditions set out in

Table A.1.
A list of all parts in the ISO 5667 series can be found on the ISO website.
iv © ISO 2018 – All rights reserved
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SIST EN ISO 5667-3:2018
ISO 5667-3:2018(E)
Introduction

This document is intended to be used in conjunction with ISO 5667-1, which deals with the design of

sampling programmes and sampling techniques.

Where possible this document has been brought into line with current standards. Where new research

or validation results have provided new insights, the latest knowledge has been used.

Guidance on validation protocols can be found in ISO 17034.

ISO 5667-3 provides in Table A.1 validated preservation times and/or conditions as well as descriptions

of best practice. Table A.1 also refers, for each analyte, to those ISO standards available at the date of

publication of this ISO 5667-3. This is however not an exhaustive list. Other methods may be used when

they have been validated. However, it is strongly recommended that where a method validation is not

available, the preservation times for the analyte as listed in Table A.1 for ISO test methods be followed.

The preservation and storage conditions and maximum storage times per analyte as listed in Table A.1

should be regarded as default conditions to be applied in the absence of any other information.

However, if validation of preservation techniques and holding times has been carried out, relative

to specific circumstances and matrices, by a laboratory, then, provided that it can produce evidence

of this validation where they differ from those set out in Table A.1 of this standard, these validated

preservation and storage conditions and maximum storage times are deemed acceptable for use by the

validating laboratories.

Attention is drawn to the proposed development of a new part in the ISO 5667 series, which further

elaborates on ISO 5667-3:2018, Annex C, and which will contain guidelines and the elaboration of the

required techniques of how to validate new storage times or preservative methods and details of the

techniques described.
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SIST EN ISO 5667-3:2018
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SIST EN ISO 5667-3:2018
INTERNATIONAL STANDARD ISO 5667-3:2018(E)
Water quality — Sampling —
Part 3:
Preservation and handling of water samples

NOTICE — This document and the analytical International Standards listed in Annex A are

complementary. Where no analytical International Standard is applicable, the technique(s)

described in Tables A.1 to A.3 take(s) normative status.

When new or revised analytical standards are developed with storage times or preservative

techniques differing from those in Tables A.1 to A.3, then the storage times or preservative

techniques should be validated and presented to ISO/TC 147/SC 6/WG 3 for incorporation into

the next revision of this document.
1 Scope

This document specifies general requirements for sampling, preservation, handling, transport and

storage of all water samples including those for biological analyses.

It is not applicable to water samples intended for microbiological analyses as specified in ISO 19458,

ecotoxicological assays, biological assays and passive sampling as specified in the scope of ISO 5667-23.

This document is particularly appropriate when spot or composite samples cannot be analysed on site

and have to be transported to a laboratory for analysis.
2 Normative references

The following documents are referred to in the text in such a way that some or all of their content

constitutes requirements 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 3696, Water for analytical laboratory use — Specification and test methods
ISO 5667 (all parts), Water quality — Sampling
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 at the following addresses:

— IEC Electropedia: available at http: //www .electropedia .org/
— ISO Online browsing platform: available at https: //www .iso .org/obp
3.1
integrity

property that the parameter(s) of interest, information or content of the sample container has not been

altered or lost in an unauthorized manner or subject to loss of representativeness

© ISO 2018 – All rights reserved 1
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SIST EN ISO 5667-3:2018
ISO 5667-3:2018(E)
3.2
sample preservation

any procedure used to stabilize a sample in such a way that the properties under examination are

maintained stable from the collection step until preparation for analysis

Note 1 to entry: Different analytes may require several samples from the same source that are stabilized by

different procedures.
[SOURCE: ISO 11074:2015, 4.4.20, modified — Note 1 to entry has been added.]
3.3
sample storage

process, and the result of keeping a sample available under predefined conditions, usually for a specified

time interval between collection and further treatment of a sample
Note 1 to entry: Specified time is the maximum time interval.

[SOURCE: ISO 11074:2015, 4.4.22, modified — Note 1 to entry has been added; “soil sample” has been

changed to “sample”.]
3.4
storage time

period of time between filling of the sample container and further treatment of the sample in the

laboratory, if stored under predefined conditions

Note 1 to entry: Sampling finishes as soon as the sample container has been filled with the sample. Storage time

ends when the sample is taken by the analyst to start sample preparation prior to analysis.

Note 2 to entry: Further treatment is, for most analytes, a solvent extraction or acid destruction. The initial steps

of sample preparation can be steps complementary to the storage conditions for the maintenance of analyte

concentrations.
4 Sampling and chain of custody

If there is a need to take samples, this is done according to a sampling programme. The first step is to

design a sampling programme. Guidance on this topic is given in ISO 5667-1.

Depending on the sample type and matrix, the guidelines found in ISO 19458 and in the relevant part(s)

of ISO 5667 shall be consulted.

The process of preservation and handling of water samples consists of several steps. During this

process, the responsibility for the samples might change. To ensure the integrity of the samples, all

steps involving the sample shall be documented.

All preparation procedures shall be checked to ensure positive or negative interferences do not occur.

As a minimum, this shall include the analysis of blanks (e.g. field blank or sample container) or samples

containing known levels of relevant analytes as specified in ISO 5667-14.
5 Reagents and materials

WARNING — Certain preservatives (e.g. acids, alkalis, formaldehyde) need to be used with

caution. Sampling personnel should be warned of potential dangers, and appropriate safety

procedures should be followed.

The following reagents are used for the sample preservation and shall only be prepared according

to individual sampling requirements. All reagents used shall be of at least analytical reagent grade

and water shall be of at least ISO 3696, grade 2. Acids referred to in this document are commercially

available “concentrated” acids.
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SIST EN ISO 5667-3:2018
ISO 5667-3:2018(E)

All reagents shall be labelled with a “shelf-life”. The shelf-life represents the period for which the

reagent is suitable for use, if stored correctly. This shelf-life shall not be exceeded. Any reagents that are

not completely used by the expiry of the shelf-life date shall be discarded.
NOTE Often the shelf-life of reagents is supplied by the receiving laboratory.

Check reagents periodically, e.g. by field blanks, and discard any reagent found to be unsuitable.

Between on-site visits, reagents shall be stored separately from sample containers and other equipment

in a clean, secure cabinet in order to prevent contamination.

Each sample shall be labelled accordingly, after the addition of the preservative. Otherwise, there could

be no visible indication as to which samples have been preserved, and which have not.

5.1 Solids.
5.1.1 Sodium thiosulfate pentahydrate, Na S O ·5H O, w(Na S O ·5H O) > 99 %.
2 2 3 2 2 2 3 2
5.1.2 Ascorbic acid, C H O , w(C H O ) > 99 %.
6 8 6 6 8 6
5.1.3 Sodium hydroxide, NaOH, w(NaOH) > 99 %.
5.1.4 Sodium tetraborate decahydrate, Na B O ·10H O, w(Na B O ·10H O), > 99 %.
2 4 7 2 2 4 7 2

CAUTION — Sodium tetraborate decahydrate is known to be a carcinogen, mutagen and

reproductive toxin (CMR).
5.1.5 Hexamethylenetetramine (hexamine, urotropine), C H N , w(C H N ) > 99 %.
6 12 4 6 12 4
5.1.6 Potassium iodide, KI, w(KI) > 99 %.
5.1.7 Iodine, I w(I ) > 99 %.
2, 2
5.1.8 Sodium acetate, C H NaO , w(C H NaO ) > 99 %.
2 3 2 2 3 2
5.1.9 Ethylenediamine, C H N , w(C H N ) > 99 %.
2 8 2 2 8 2
5.2 Solutions.
5.2.1 Zinc acetate solution C H O Zn (10 g/l).
4 6 4

Dissolve 10,0 g of zinc acetate in ∼100 ml of water . Dilute to 100 ml with water. Store the solution in a

polypropylene or glass bottle for a maximum period of 1 a.

5.2.2 Orthophosphoric acid (ρ ≈ 1,7 g/ml), H PO , w(H PO ) > 85 %, c(H PO ) = 15 mol/l.

3 4 3 4 3 4
5.2.3 Hydrochloric acid (ρ ≈ 1,2 g/ml), HCl, w(HCl) > 36 %, c(HCl) = 12,0 mol/l.
5.2.4 Nitric acid (ρ ≈ 1,42 g/ml), HNO , w(HNO ) > 65 %, c(HNO ) = 15,8 mol/l.
3 3 3
5.2.5 Sulfuric acid (ρ ≈ 1,84 g/ml), H SO (freshly prepared).
2 4

Dilute concentrated sulfuric acid (H SO ), ρ ≈ 1,84 g/ml, w(H SO ) ≈ 98 % 1 + 1 by carefully adding the

2 4 2 4
concentrated acid to an equal volume of water and mix.
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SIST EN ISO 5667-3:2018
ISO 5667-3:2018(E)

WARNING — Adding the concentrated acid to the water can give violent reactions because of an

exothermic reaction.
5.2.6 Sodium hydroxide solution (ρ ≈ 0,40 g/ml), NaOH.

5.2.7 Formaldehyde solution (formalin), CH O, φ(CH O) = 37 % to 40 % (freshly prepared).

2 2

WARNING — Beware of formaldehyde vapours. Do not store large numbers of samples in small

work areas.
5.2.8 Disodium salt of ethylenediaminetetraacetic acid (EDTA) (ρ ≈ 0,025 g/ml),
C H N Na O ⋅2H O, w(C H N Na O ⋅2H O) > 99 %.
10 14 2 2 8 2 10 14 2 2 8 2
Dissolve 25 g EDTA in 1 000 ml of water.
5.2.9 Ethanol C H OH, φ(C H OH) = 96 %.
2 5 2 5

5.2.10 Alkaline Lugol’s solution, 100 g potassium iodide (5.1.6), 50 g iodine (5.1.7), and 250 g sodium

acetate (5.1.8) in 1 000 ml water to pH 10.

5.2.11 Acidic Lugol’s solution, 100 g potassium iodide (5.1.6), 50 g iodine (5.1.7) and 100 ml glacial

acetic acid (5.2.17) in 1 000 ml water to pH 2.

5.2.12 Neutralized formaldehyde solution, formaldehyde solution (5.2.7) neutralized with sodium

tetraborate (5.1.4) or hexamethylenetetramine (5.1.5). Formalin solution at 100 g/l gives a final solution

of φ(CH O) = 3,7 % to 4,0 %.

WARNING — Beware of formaldehyde vapours. Do not store large numbers of samples in small

work areas.
5.2.13 Ethanol preservative solution.

Ethanol (5.2.9), formaldehyde solution (5.2.7) and glycerol (5.2.18) (100 + 2 + 1 parts by volume,

respectively).

5.2.14 Sodium hypochlorite NaOCl, w(NaOCl) = 10 %. Dissolve 100 g sodium hypochlorite (NaOCl) in

1 000 ml of water.

5.2.15 Potassium iodate KIO , w(KIO ) = 10 %. Dissolve 100 g potassium iodate (KIO ) in 1 000 ml

3 3 3
of water.
5.2.16 Methanoic acid (formic acid) CH O , φ(CH O ) > 98 %.
2 2 2 2
5.2.17 Glacial acetic acid C H O , w(C H O ) > 99 %.
2 4 2 2 4 2
5.2.18 Glycerol (glycerin, glycerine) C H (OH) .
3 5 3
5.3 Materials.
5.3.1 Container and cap, types as specified in Tables A.1 to A.3.

5.3.2 Filter, pore size 0,40 µm to 0,45 µm, unless a different filter size is specified in the analytical

International Standard.
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SIST EN ISO 5667-3:2018
ISO 5667-3:2018(E)
6 Containers
6.1 Container selection and preparation

The choice of sample container (5.3.1) is of major importance and ISO 5667-1 provides some guidance

on this subject.

Details of the type of container used for the collection and storage of samples are given in Tables A.1

to A.3. The same considerations given to this selection of suitable container material shall also be given

to the selection of cap liner materials.

Sample containers shall be made of a material appropriate for preserving the natural properties of both

the sample and the expected range of contaminants. Suitable types of containers for each analyte to be

measured are given in Tables A.1 to A.3.

NOTE For very low concentrations of metals, containers prescribed can be different from those used for

higher concentrations. Details can be found in Table A.1 or in the analytical International Standards.

If the samples are to be frozen, suitable containers, such as polyethylene (PE) or polytetrafluoroethylene

(PTFE), shall be used to prevent breakage.

The use of disposables is preferred. Some manufacturers supply containers with a certificate of

cleanliness. If such a certificate of cleanliness is supplied, it is not necessary to clean or rinse the

containers before use.
6.2 Filtration on site
Filtration on site is required in some cases.

— Groundwaters shall be filtered on site if dissolved metals need to be analysed.

— Waters shall be filtered (5.3.2) on site, if this is required according to Annex A. Unless specified

otherwise, a filter pore size 0,40 µm to 0,45 µm shall be used.

If immediate filtration on site is impossible, then the reason and the time between sampling and

filtration shall be added to the test report.
6.3 Filling the container

The container (5.3.1) shall be filled completely unless prescribed differently in Tables A.1 to A.3 or the

analytical International Standard used. If the samples are to be frozen as part of their preservation,

sample containers shall not be completely filled. This is in order to prevent breakage which may arise

from expansion of ice during the freezing and thawing process.

If no preservatives are present in the bottle, then prerinsing the bottle may be advisable. Guidance on

prerinsing can be found in ISO 5667-14.
7 Sample handling and preservation
7.1 Sample handling and preservation for physical and chemical examination

Waters, particularly fresh waters, waste waters and groundwaters, are susceptible to changes

as a result of physical, chemical or biological reactions which may take place between the time of

sampling and the commencement of analysis. The nature and rate of these reactions are often such

that, if precautions are not taken during sampling, transport and storage (for specific analytes), the

concentrations determined are different to those existing at the time of sampling.

The extent of these changes is dependent on the chemical and biological nature of the sample, its

temperature, its exposure to light, the type of the container in which it is placed, the time between

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SIST EN ISO 5667-3:2018
ISO 5667-3:2018(E)

sampling and analysis, and the conditions to which it is subjected, e.g. agitation during transport.

Further specific causes of variation are listed in a) to f).

a) The presence of bacteria, algae and other organisms can consume certain constituents of

the samples. These organisms can also modify the nature of the constituents to produce new

constituents. This biological activity affects, for example, the concentrations of dissolved oxygen,

carbon dioxide, compounds of nitrogen, phosphorus and, sometimes, silicon.

b) Certain compounds can be oxidized either by dissolved oxygen present in the samples, or by

atmospheric oxygen [e.g. organic compounds, Fe(II) and sulfides].

c) Certain substances can precipitate out of solution, e.g. calcium carbonate, metals, and metallic

compounds such as Al(OH) , or can be lost to the vapour phase (e.g. oxygen, cyanides, and mercury).

d) Absorption of carbon dioxide from air can modify pH, conductivity, and the concentration of

dissolved carbon dioxide. Passage of compounds like ammonia and silicon fluoride through some

types of plastics may also affect pH or conductivity.

e) Dissolved metals or metals in a colloidal state, as well as certain organic compounds, can be

irreversibly adsorbed on to the surface of the containers or solid materials in the samples.

f) Polymerized products can depolymerize, and conversel
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