oSIST prEN ISO 5667-3:2023
(Main)Water quality - Sampling - Part 3: Preservation and handling of water samples (ISO/DIS 5667-3:2023)
Water quality - Sampling - Part 3: Preservation and handling of water samples (ISO/DIS 5667-3:2023)
Wasserbeschaffenheit - Probenahme - Teil 3: Konservierung und Handhabung von Wasserproben (ISO/DIS 5667-3:2023)
Dieses Dokument legt allgemeine Anforderungen an die Probenahme, Konservierung, Handhabung, den Transport und die Lagerung aller Wasserproben für physikalisch-chemische, chemische, hydrobiologische und mikrobiologische Untersuchungen sowie radiochemische Analyten und Aktivitäten fest.
Eine Anleitung zur Validierung der Aufbewahrungszeiten von Wasserproben ist in ISO/TS 5667 25 enthalten.
Es ist nicht anwendbar auf Wasserproben für ökotoxikologische Untersuchungen, für biologische Untersuchungen, zur passiven Probenahme nach den Festlegungen im Anwendungsbereich von ISO 5667 23 sowie auf Mikroplastikpartikel und fasern.
Dieses Dokument ist besonders geeignet, wenn Proben nicht vor Ort untersucht werden können und zu Analyse in ein Labor transportiert werden müssen.
Dieses Dokument und die Internationalen Analysenormen können wie in Bild 1 dargestellt angewendet werden.
Qualité de l'eau - Échantillonnage - Partie 3: Conservation et manipulation des échantillons d'eau (ISO/DIS 5667-3:2023)
Kakovost vode - Vzorčenje - 3. del: Konzerviranje in ravnanje z vzorci vode (ISO/DIS 5667-3:2023)
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
oSIST prEN ISO 5667-3:2023
01-marec-2023
Kakovost vode - Vzorčenje - 3. del: Konzerviranje in ravnanje z vzorci vode
(ISO/DIS 5667-3:2023)
Water quality - Sampling - Part 3: Preservation and handling of water samples (ISO/DIS
5667-3:2023)
Wasserbeschaffenheit - Probenahme - Teil 3: Konservierung und Handhabung von
Wasserproben (ISO/DIS 5667-3:2023)
Qualité de l'eau - Échantillonnage - Partie 3: Conservation et manipulation des
échantillons d'eau (ISO/DIS 5667-3:2023)
Ta slovenski standard je istoveten z: prEN ISO 5667-3
ICS:
13.060.45 Preiskava vode na splošno Examination of water in
general
oSIST prEN ISO 5667-3:2023 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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oSIST prEN ISO 5667-3:2023
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oSIST prEN ISO 5667-3:2023
DRAFT INTERNATIONAL STANDARD
ISO/DIS 5667-3
ISO/TC 147/SC 6 Secretariat: BSI
Voting begins on: Voting terminates on:
2023-01-05 2023-03-30
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
ICS: 13.060.45
This document is circulated as received from the committee secretariat.
THIS DOCUMENT IS A DRAFT CIRCULATED
FOR COMMENT AND APPROVAL. IT IS
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oSIST prEN ISO 5667-3:2023
ISO/DIS 5667-3:2023(E)
DRAFT INTERNATIONAL STANDARD
ISO/DIS 5667-3
ISO/TC 147/SC 6 Secretariat: BSI
Voting begins on: Voting terminates on:
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
ICS: 13.060.45
This document is circulated as received from the committee secretariat.
COPYRIGHT PROTECTED DOCUMENT
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© ISO 2023
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NATIONAL REGULATIONS.
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ii
© ISO 2023 – All rights reserved
PROVIDE SUPPORTING DOCUMENTATION. © ISO 2022
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oSIST prEN ISO 5667-3:2023
ISO/DIS 5667-3:2022(E)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 2
3 Terms and definitions . 3
4 Sampling and chain of custody . 3
5 Reagents and materials . 4
5.1 Solids . 4
5.2 Solutions . 5
5.3 Materials . 6
6 Containers . 6
6.1 Container selection and preparation . 6
6.2 On-site filtration . . 6
6.3 Filling the container . . 7
7 Sample handling and preservation . 7
7.1 Sample handling and preservation for physical and chemical analysis . 7
7.2 Sample handling and preservation for hydrobiological analysis . 7
7.3 Sample handling and preservation for radiochemical analysis . 8
8 Sample transport . 8
9 Identification of samples .9
10 Sample reception .10
11 Sample storage .10
Annex A (informative) Techniques for sample preservation .11
Annex B (informative) Container preparation .62
Bibliography .63
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oSIST prEN ISO 5667-3:2023
ISO/DIS 5667-3:2022(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 sixth edition cancels and replaces the fifth edition (ISO 5667-3:2018), which has been technically
revised.
The main changes compared to the previous edition are as follows:
— Addition of a reference to ISO/TS 5667-25 Water quality — Guideline on the validation of the storage
time of water samples;
— Addition of a flow diagram for preservation and storage of water samples;
— Updated references in Table A.1 and added references in Tables A.2 and A.3;
— Table A.1 has been splitted into an inorganic (A.1) and an organic (A.2) part;
— Addition of Table A.4 (Microbiological analysis);
— Addition of types of water to Tables A.1 to A.5;
— Explanation of the added terms used in Tables A.1 to A.5.
A list of all parts in the ISO 5667 series can be found on the ISO website.
iv
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oSIST prEN ISO 5667-3:2023
ISO/DIS 5667-3:2022(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.
[86]
Guidance on validation protocols can be found in ISO/TS 5667-25 and ISO 17034 .
ISO 5667-3 provides in Tables A.1 to A.5 where stated validated preservation times or conditions
according to ISO/TS 5667-25 or ISO 5667-3:2018, Annex C as well as descriptions of best practice.
Tables A.1 to A.5 also refer, for each analyte, to those analytical International Standards available at the
date of publication of this version of ISO 5667-3. This is however not an exhaustive list. Other preservation
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 Tables A.1 to A.5
for ISO test methods be followed. In case more than one storage time is provided in Tables A.1 to A.5 the
order of preferred use is:
— Validated;
— Provided by standard;
— Best practice.
The preservation and storage conditions and maximum storage times per analyte as listed in Tables A.1
to A.5 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 Tables A.1 to A.5 of this standard, these validated
preservation and storage conditions and maximum storage times are deemed acceptable for use by
the validating laboratories. If national standards contain information on preservation, these are to be
applied. This means that in these cases the contents of ISO 5667-3 are only to be considered informative.
Attention is drawn to the new part 25 in the ISO 5667 series, which further elaborates on
ISO 5667-3:2018, Annex C, and which contains 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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oSIST prEN ISO 5667-3:2023
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oSIST prEN ISO 5667-3:2023
DRAFT INTERNATIONAL STANDARD ISO/DIS 5667-3:2022(E)
Water quality — Sampling —
Part 3:
Preservation and handling of water samples
1 Scope
This document specifies general requirements for sampling, preservation, handling, transport
and storage of all water samples for physicochemical, chemical, hydrobiological and microbiological
analyses and radiochemical analytes and activities.
Guidance on the validation of storage times of water samples is provided in ISO/TS 5667-25.
It is not applicable to water samples intended for ecotoxicological assays, biological assays, passive
sampling as specified in the scope of ISO 5667-23 and microplastic particles and fibres.
This document is particularly appropriate when samples cannot be analysed on site and have to be
transported to a laboratory for analysis.
This document and the analytical International Standards can be used as presented in Figure 1.
1
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oSIST prEN ISO 5667-3:2023
ISO/DIS 5667-3:2022(E)
WARNING — ‘Provided by standard’ and ‘validated’ could be based on previous standards and
methods and therefore not be in line with ISO/TS 5667-25. This information can be interpreted
by a qualified and experienced person.
Figure 1 — Flow diagram for preservation and storage of water samples
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.
2
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oSIST prEN ISO 5667-3:2023
ISO/DIS 5667-3:2022(E)
For undated references, the latest edition of the referenced document (including any amendments)
applies.
ISO 5667 (all parts), Water quality — Sampling
ISO 19458:2007, 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 https:// 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
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 accordingly 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 the relevant part(s) of ISO 5667
and in ISO 19458 shall be consulted.
3
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oSIST prEN ISO 5667-3:2023
ISO/DIS 5667-3:2022(E)
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.
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 and waters used shall be of at least analytical grade.
Acids referred to in this document are commercially available "concentrated" acids.
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 1 Often the shelf-life of reagents is supplied by the receiving laboratory.
NOTE 2 For reagents that in the specific conditions are not likely to change during time, a periodically check
of the storage and packaging could be sufficient.
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 Sodium hydroxide, NaOH, w(NaOH) > 99 %.
5.1.3 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).
5.1.4 Hexamethylenetetramine (hexamine, urotropine), C H N , w(C H N ) > 99 %.
6 12 4 6 12 4
5.1.5 Potassium iodide, KI, w(KI) > 99 %.
5.1.6 Iodine, I w(I ) > 99 %.
2, 2
5.1.7 Sodium acetate, C H NaO , w(C H NaO ) > 99 %.
2 3 2 2 3 2
5.1.8 Ethylenediamine, C H N , w(C H N ) > 99 %.
2 8 2 2 8 2
4
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oSIST prEN ISO 5667-3:2023
ISO/DIS 5667-3:2022(E)
5.2 Solutions
5.2.1 Zinc acetate solution C H O Zn⋅2H O (100 g/l).
4 6 4 2
Dissolve 10,0 g of zinc acetate dihydrate in ∼90 ml of water. Dilute to 100 ml with water.
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 ≈ 1,43 g/ml), H SO , w(HNO ) ≈ 49 %, c(H SO ) ≈ 9 mol/l.
2 4 3 2 4
Dilute concentrated sulfuric acid (H SO ), ρ ≈ 1,84 g/ml, w(H SO ) ≈ 98 % 1 + 1 by carefully adding
2 4 2 4
the concentrated acid to an equal volume of water and mix.
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 % (freshly prepared).
2 2
WARNING — Beware of formaldehyde vapours. Do not store large numbers of samples in small
working 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 Acidic Lugol’s solution, 100 g potassium iodide (5.1.5), 50 g iodine (5.16) and 100 ml glacial
acetic acid (5.2.16) in 1 000 ml water to pH 2.
5.2.11 Alkaline Lugol’s solution, 100 g potassium iodide (5.1.5), 50 g iodine (5.1.6), and 250 g sodium
acetate (5.1.7) in 1 000 ml water to pH 10.
5.2.12 Neutralized formaldehyde solution, formaldehyde solution (5.2.7) neutralized with sodium
tetraborate (5.1.3) or hexamethylenetetramine (5.1.4). Formalin solution at 100 g/l gives a final
solution of φ(CH O) = 3,7 % to 4,0 %.
2
WARNING — Beware of formaldehyde vapours. Do not store large numbers of samples in small
working areas.
5.2.13 Ethanol preservative solution.
Ethanol (5.2.9), formaldehyde solution (5.2.7) and glycerol (5.2.17) (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
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oSIST prEN ISO 5667-3:2023
ISO/DIS 5667-3:2022(E)
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 Glacial acetic acid C H O , w(C H O ) > 99 %.
2 4 2 2 4 2
5.2.17 Glycerol (glycerin, glycerine) C H (OH) .
3 5 3
5.2.18 Sodiumhydrogensulphate NaHSO .
4
5.3 Materials
5.3.1 Container and cap, types as specified in Tables A.1 to A.5.
5.3.2 Filter, membrane, pore size 0,40 µm to 0,45 µm, unless a different filter size is specified
in the analytical International Standard.
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.5. The same considerations given to this selection of suitable container material shall also be given
to the selection of cap liner materials. For microbiological analyses clean sterile bottles shall be used.
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.5.
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 On-site filtration
On-site filtration is required in some cases:
— If dissolved metals need to be analysed. Filter on site or as soon as possible after sampling.
Acidify to pH < 2 with HNO (5.2.4).
3
— If required according to Tables A.1 to A.5, e.g. ammonium, nitrate, nitrite, phosphate, sulfate
and silicates.
If immediate filtration on site is impossible where required, then the reason and the time between
sampling and filtration shall be added to the test report.
6
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oSIST prEN ISO 5667-3:2023
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6.3 Filling the container
Containers (5.3.1) should be filled as presecribed in Tables A.1 to A.5 or the analytical International
Standard. If there are no instructions regarding the filling of the containers, they should be filled
completely unless the samples are to be frozen as part of their preservation, the sample containers
shall not be filled completely. This is in order to prevent breakage which may arise from expansion of
the water sample during the freezing and thawing process.
If no preservatives are present in the bottle, 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 analysis
Waters, particularly surface waters, waste waters and groundwaters, are susceptible to changes
as a result of physical, chemical or hydrobiological 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
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 hydrobiological 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).
3
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 (see Table A.1) 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 conversely, simple compounds can polymerize.
Changes to particular constituents vary both in degree and rate, not only as a function of the type of
water, but also, for the same water type, as a function of seasonal conditions.
These changes are often sufficiently rapid to modify the sample considerably in a short time. In all
cases, it is essential to take precautions to minimize these reactions and, in the case of many analytes,
to analyse the sample with a minimum of delay. On-site filtration may be required as a precaution (6.2).
Details of the sample preservation are given in Tables A.1 and A.2.
7.2 Sample handling and preservation for hydrobiological analysi
...
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