SIST EN ISO 5667-3:2004
(Main)Water quality - Sampling - Part 3: Guidance on the preservation and handling of water samples (ISO 5667-3:2003)
Water quality - Sampling - Part 3: Guidance on the preservation and handling of water samples (ISO 5667-3:2003)
With a scope of providing information on the comparative value and guidance on the selection of test methods for determining the apparent fracture toughness of monolithic advanced technical ceramics.
Wasserbeschaffenheit - Probenahme - Teil 3: Anleitung zur Konservierung und Handhabung von Proben (ISO 5667-3:2003)
Dieser Teil der ISO 5667 gibt allgemeine Hinweise bezüglich der Vorkehrungen, die bei der Konservierung und dem Transport aller Wasserproben einschließlich derer für biologische Untersuchungen getroffen werden; Proben zur mikrobiologischen Untersuchung sind ausgeschlossen.
Diese Hinweise sind besonders für jene Proben (Einzel- oder zusammengesetzte Probe) geeignet, die nicht unmittelbar vor Ort untersucht werden können und hierfür in das Labor gebracht werden müssen.
Qualité de l'eau - Echantillonnage - Partie 3: Lignes directrices pour la conservation et la manipulation des échantillons d'eau (ISO 5667-3:2003)
L'ISO 5667-3:2003 donne des lignes directrices générales sur les précautions à prendre pour conserver et transporter toutes les sortes d'échantillons d'eau, y compris ceux destinés aux analyses biologiques, à l'exclusion de ceux destinés aux analyses microbiologiques.
Ces lignes directrices s'appliquent en particulier chaque fois qu'un échantillon ponctuel ou composite ne peut être analysé sur site et doit être transporté vers un laboratoire pour y être analysé.
Kakovost vode – Vzorčenje – 3. del: Navodilo za shranjevanje in ravnanje z vzorci vode (ISO 5667-3:2003)
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
SIST EN ISO 5667-3:2004
01-februar-2004
1DGRPHãþD
SIST EN ISO 5667-3:1996
.DNRYRVWYRGH±9]RUþHQMH±GHO 1DYRGLOR]DVKUDQMHYDQMHLQUDYQDQMH]Y]RUFL
YRGH ,62
Water quality - Sampling - Part 3: Guidance on the preservation and handling of water
samples (ISO 5667-3:2003)
Wasserbeschaffenheit - Probenahme - Teil 3: Anleitung zur Konservierung und
Handhabung von Proben (ISO 5667-3:2003)
Qualité de l'eau - Echantillonnage - Partie 3: Lignes directrices pour la conservation et la
manipulation des échantillons d'eau (ISO 5667-3:2003)
Ta slovenski standard je istoveten z: EN ISO 5667-3:2003
ICS:
13.060.45 Preiskava vode na splošno Examination of water in
general
SIST EN ISO 5667-3:2004 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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EUROPEAN STANDARD
EN ISO 5667-3
NORME EUROPÉENNE
EUROPÄISCHE NORM
December 2003
ICS 13.060.45 Supersedes EN ISO 5667-3:1995
English version
Water quality - Sampling - Part 3: Guidance on the preservation
and handling of water samples (ISO 5667-3:2003)
Qualité de l'eau - Echantillonnage - Partie 3: Lignes Wasserbeschaffenheit - Probenahme - Teil 3: Anleitung zur
directrices pour la conservation et la manipulation des Konservierung und Handhabung von Wasserproben (ISO
échantillons d'eau (ISO 5667-3:2003) 5667-3:2003)
This European Standard was approved by CEN on 21 November 2003.
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 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 Management Centre has the same status as the official
versions.
CEN members are the national standards bodies of Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece,
Hungary, Iceland, Ireland, Italy, Luxembourg, Malta, Netherlands, Norway, Portugal, Slovakia, Spain, Sweden, Switzerland and United
Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: rue de Stassart, 36 B-1050 Brussels
© 2003 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 5667-3:2003 E
worldwide for CEN national Members.
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EN ISO 5667-3:2003 (E)
CORRECTED 2004-03-03
Foreword
This document (EN ISO 5667-3:2003) 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 June 2004, and conflicting national
standards shall be withdrawn at the latest by June 2004.
This document supersedes EN ISO 5667-3:1995.
According to the CEN/CENELEC Internal Regulations, the national standards organizations of
the following countries are bound to implement this European Standard: Austria, Belgium, Czech
Republic, Denmark, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy,
Luxembourg, Malta, Netherlands, Norway, Portugal, Slovakia, Spain, Sweden, Switzerland and
the United Kingdom.
Endorsement notice
The text of ISO 5667-3:2003 has been approved by CEN as EN ISO 5667-3:2003 without any
modifications.
NOTE Normative references to International Standards are listed in annex ZA (normative).
2
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EN ISO 5667-3:2003 (E)
Annex ZA
(normative)
Normative references to international publications
with their relevant European publications
This European Standard incorporates by dated or undated reference, provisions from other
publications. These normative references are cited at the appropriate places in the text and the
publications are listed hereafter. For dated references, subsequent amendments to or revisions of
any of these publications apply to this European Standard only when incorporated in it by
amendment or revision. For undated references the latest edition of the publication referred to
applies (including amendments).
NOTE Where an International Publication has been modified by common modifications, indicated
by (mod.), the relevant EN/HD applies.
Publication Year Title EN Year
ISO 3696 1987 Water for analytical laboratory use - EN ISO 3696 1995
Specification and test methods
ISO 5667-1 1980 Water quality - Sampling - Part 1: Guidance EN 25667-1 1993
on the design of sampling programmes
ISO 5667-2 1991 Water quality - Sampling - Part 2: Guidance EN 25667-2 1993
on sampling techniques
ISO 5667-16 1998 Water quality - Sampling - Part 16: EN ISO 5667-16 1998
Guidance on biotesting of samples
3
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INTERNATIONAL ISO
STANDARD 5667-3
Third edition
2003-12-15
Water quality — Sampling —
Part 3:
Guidance on the preservation and
handling of water samples
Qualité de l'eau — Échantillonnage —
Partie 3: Lignes directrices pour la conservation et la manipulation des
échantillons d'eau
Reference number
ISO 5667-3:2003(E)
©
ISO 2003
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ISO 5667-3:2003(E)
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ii © ISO 2003 — All rights reserved
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ISO 5667-3:2003(E)
Contents Page
Foreword. iv
Introduction . vi
1 Scope. 1
2 Normative references . 1
3 Preservation of samples. 1
4 Recommendations . 8
5 Identification of samples. 9
6 Transport of samples. 9
7 Reception of samples . 9
Annex A (informative) Dutch investigation on prolonged preservation times. 28
Bibliography . 31
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ISO 5667-3:2003(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.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International Standards
adopted by the technical committees are circulated to the member bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the member bodies casting a vote.
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.
ISO 5667-3 was prepared by Technical Committee ISO/TC 147, Water quality Subcommittee SC 6, Sampling
(general methods).
This third edition cancels and replaces the second edition (ISO 5667-3:1994), which has been technically
revised.
ISO 5667 consists of the following parts, under the general title Water quality — Sampling:
Part 1: Guidance on the design of sampling programmes
Part 2: Guidance on sampling techniques
Part 3: Guidance on the 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 and water used for food and beverage processing
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 from sewage and water-treatment works
Part 14: Guidance on quality assurance of environmental water-sampling and handling
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ISO 5667-3:2003(E)
Part 15: Guidance on preservation and handling of sludge and sediment samples
Part 16: Guidance on biotesting of samples
Part 17: Guidance on sampling of suspended sediments
Part 18: Guidance on sampling of groundwater at contaminated sites
Part 19: Guidance on sediment sampling in marine areas
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ISO 5667-3:2003(E)
Introduction
This part of ISO 5667 is intended to be used in conjunction with ISO 5667-1 and ISO 5667-2, which deal with
the design of sampling programmes and sampling techniques respectively.
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INTERNATIONAL STANDARD ISO 5667-3:2003(E)
Water quality — Sampling —
Part 3:
Guidance on the preservation and handling of water samples
1 Scope
This part of ISO 5667 gives general guidelines on the precautions to be taken to preserve and transport all
water samples including those for biological analyses but not those intended for microbiological analysis.
These guidelines are 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 referenced documents are indispensable for the application of this document. For dated
references, only the edition cited applies. For undated references, the latest edition of the referenced
document (including any amendments) applies.
ISO 3696:1987, Water for analytical laboratory use — Specification and test methods
ISO 5667-1:1980, Water quality — Sampling — Part 1: Guidance on the design of sampling programmes
ISO 5667-2:1991, Water quality — Sampling — Part 2: Guidance on sampling techniques
ISO 5667-14:1998, Water quality — Sampling — Part 14: Guidance on quality assurance of environmental
water sampling and handling
ISO 5667-16:1998, Water quality — Sampling — Part 16: Guidance on biotesting of samples
ISO Guide 34:2000, General requirements for the competence of reference material procedures
3 Preservation of samples
3.1 General considerations
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 determinands), the concentrations determined may
be 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 nature of the container in which it is placed, the time between sampling
and analysis, and the conditions to which it is subjected, for example agitation during transport. Further
specific causes of variation are as follows.
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ISO 5667-3:2003(E)
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 and
compounds, of nitrogen, phosphorus and sometimes silicon.
b) Certain compounds can be oxidized by the 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 [for example calcium carbonate, metals and metallic
compounds such as Al(OH) ] or be lost to the vapour phase (for example oxygen, cyanides and mercury).
3
d) The pH and conductivity can be modified and the dissolved carbon dioxide changed by the absorption of
carbon dioxide from air.
e) Dissolved metals or metals in a colloidal state, as well as certain organic compounds can be irreversibly
adsorbed onto 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.
lt should be emphasized that 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
determinands, to analyse the sample with a minimum of delay.
Preservation of water samples is necessary for a number of reasons, therefore it is generally necessary to
choose, from the various possible methods of preservation, a method that does not introduce contamination.
Fresh waters and groundwaters can be stored more successfully. In the case of potable waters, storage can
be solved easily by cooling, because these waters are less susceptible to biological and chemical reactions.
In many cases, if samples are analysed within 24 h, the preservation technique of cooling to between 1 °C to
5 °C is sufficient. Municipal or industrial sewage plant effluents should be preserved immediately after
sampling, because of the high biological activities in these samples.
This part of ISO 5667 describes the most commonly used preservation techniques and storage times.
[4]
In spite of investigations which have been carried out in order to recommend methods that enable water
samples to be stored without changes occurring to their composition, no guidance has been reported that
covers all situations. Users of particular test methods and analytical techniques described in International
Standards prepared by ISO/TC 147 are encouraged to take into account any relevant guidance offered in this
part of ISO 5667 when making decisions in relation to sample preservation and handling for such methods
and techniques.
3.2 Precautions to be taken
3.2.1 Container selection
The choice of sample container is of major importance and ISO 5667-2 provides some guidance on this
subject. Details of the type of container used for the collection and storage of samples are given in Tables 1
to 4. The same considerations given to this selection of suitable container material should also be given to the
selection of cap-liner materials. The guidance given here is to help in the selection of containers for general
use.
The containers used to collect and store the samples should be selected after taking into account the following
predominant criteria (especially when the analytes are present in trace quantities).
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ISO 5667-3:2003(E)
a) Minimizing sample contamination by the container or cap material, for example leaching of inorganic
constituents from glass (especially soda glass) and organic compounds and metals from plastics. Some
coloured caps may contain significant levels of heavy metals.
b) Ability to clean and treat the walls of the container to reduce surface contamination by trace constituents
such as heavy metals or radionuclides.
c) Chemical and biological inertness of the container or cap material in order to prevent or minimize reaction
between sample constituents and the container.
d) Containers may also cause changes to constituent concentrations by adsorption or absorption of analytes.
Trace metals are particularly susceptible to these effects but other analytes (for example detergents,
pesticides, phosphates) may also be affected.
Guidance should be sought from laboratory staff on the selection of sample containers and sampling
equipment.
Other factors should also be considered, e.g. resistance to temperature extremes, resistance to breakage,
ease of sealing and reopening, size, shape, mass, availability, cost, potential for cleaning and re-use.
Container blanks should always be taken, preserved and analysed as a check on the suitability of the
container and preservation procedures (see ISO 5667-14).
3.2.2 Container preparation
3.2.2.1 General
All preparation procedures should be validated to ensure positive or negative interferences do not occur. As a
minimum, this should include the analysis of:
a) blanks;
b) samples containing known levels of relevant analytes.
If disposable or single-use containers cannot be used, it is preferable to reserve a set of containers for a
particular determinand, thereby minimizing risks of cross-contamination. Care should be taken to prevent a
container, formerly holding a sample with a high concentration of a determinand, from contaminating a
subsequent sample containing a low concentration of the same determinand.
It may be necessary to wash new containers with water containing a detergent, in order to remove dust and
residues of packing materials, followed by thorough rinsing with water of an appropriate quality. The use of
cleansing reagents and solvents may cause interferences, e.g. residual contamination by phosphate-
containing detergents when undertaking nutrient analyses. If used, all cleaning reagents and solvents should
be of an appropriate quality. For the determination of silicon, boron and surfactants, detergents should not be
used for cleaning purposes.
3.2.2.2 Detergent-washed plastic or glass containers
The procedure should be as follows.
a) Wash the container and cap with a dilute solution of detergent and water.
b) Rinse thoroughly with tap water.
c) Successively rinse twice with water of an appropriate quality.
d) Drain thoroughly and replace cap.
Automatic dish washing machines may be used for this procedure.
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ISO 5667-3:2003(E)
3.2.2.3 Solvent-washed glass containers
WARNING — Organic solvents may be hazardous. Provide suitable handling facilities and handle with
care.
The procedure should be as follows.
a) Wash the container and cap with a dilute solution of detergent and tap water.
b) Rinse thoroughly with tap water.
c) Successively rinse twice with water of an appropriate quality and dry.
d) Rinse with acetone of an appropriate quality and drain.
e) Rinse with a suitable solvent of an appropriate quality, dry and immediately replace cap.
The solvent should be compatible with the analytes of interest and the analytical method to be used.
3.2.2.4 Acid-washed containers in plastic or glass
The procedure should be as follows.
a) Wash the container and cap with a dilute solution of detergent and tap water.
b) Rinse thoroughly with tap water.
c) Rinse with an aqueous 10 % nitric acid solution.
d) Drain and completely fill with an aqueous 10 % nitric acid solution.
e) Cap and store for at least 24 h.
f) Empty the container, rinse with water of an appropriate quality and immediately replace cap.
Some manufactures will supply containers with a certificate of cleanliness. Such containers may not need
further cleaning or rinsing, provided the manufacturer supplies the containers with caps attached.
Automatic hot acid washers may be used for this procedure.
3.2.3 Filling the container
For samples requiring the determination of physico-chemical determinands, fill the container completely and
stopper it in such a way that there is no air space above the sample. This reduces interaction with the gas
phase, and minimizes agitation of the sample during transport.
Where samples are frozen as part of their preservation, sample containers should not be completely filled
(see 3.2.6).
3.2.4 Handling and preservation of samples for biological examination
The handling of samples for biological examination is different to that for samples requiring chemical analysis.
The addition of chemicals to the sample for biological examination can be used for either fixation or
preservation of the sample. The term “fixation” is used to describe the protection of morphological structures,
while the term “preservation” is used for the protection of organic matter from biochemical or chemical
degradation. Preservatives, by definition, are toxic and the addition of preservatives may lead to the death of
living organisms. Prior to death, irritation may cause the most delicate organisms, which do not have strong
cell walls, to collapse before fixation is complete. To minimize this effect, it is important that the fixation agent
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ISO 5667-3:2003(E)
enters the cell quickly. Some preservatives, for instance acid solutions of Lugol, may lead to the loss of some
taxonomical groups of organisms, which can be a problem during certain parts of the year in certain areas.
This can be addressed by using an additional preservative, such as alkaline solutions of Lugol, during, for
example, the summer period when the appearance of silico-flagellates may be frequently observed.
The preservation of samples for biological examination should meet the following criteria:
a) the effect of the preservative on the loss of the organism should be known beforehand;
b) the preservative should effectively prevent the biological degradation of organic matter at least during the
storage period of the samples;
c) the preservative should enable the taxonomical groups of organisms to be adequately studied during the
storage period of the samples.
3.2.5 Handling and preservation of samples for radiochemical analysis
WARNING — Safety precautions and shielding depend on the activity of the sample.
There is little difference between the handling of samples for radiochemical analysis and the handling of
samples for physico-chemical analysis. Safety precautions depend on the nature of the radioactivity of the
sample. The preservation techniques for these samples depend on the type of emitter and the half-life of the
radionuclide of interest.
3.2.6 Cooling or freezing of samples
The cooling or freezing of samples is only effective if the process is applied immediately after the collection of
the samples. This necessitates the use of cool-boxes or refrigerators at the sampling location. Wherever a
temperature is given for cooling, the temperature of the sample environment is meant (not the temperature of
sample itself).
Simple cooling of the sample (in melting ice or in a refrigerator at a temperature between 1 °C and 5 °C) and
storage of the sample in the dark is, in most cases, sufficient to preserve the sample during transport to the
laboratory. Cooling cannot be considered as a means of long-term storage, particularly in the case of
wastewater samples (see Table 1). The sample should be kept and stored at a temperature lower than that
observed during the process of collection or filling of the container.
A small volume of ice does not have much cooling effect upon a large volume of warm water. Where a sample
contains determinands that are likely to be affected by biological activity, and where preservation on-site is not
possible, the temperature of the sample should be taken immediately on arrival at the laboratory. This is
particularly important when samples require transporting for several hours. Samples should be analysed or
cooled immediately at receipt in the laboratory. During transport, the temperature of the cooling system should
be monitored.
In general, storage of samples at temperatures below − 20 °C allows the samples to be stored for longer
periods of time. If samples are to be frozen, the container should be made of plastic and not be filled
completely. This reduces the risk to the sample container from being damaged. For some analytes, such as
nutrient determinands, freezing of the sample is the preferred method of preservation. In these cases, quick-
freezing with dry ice is a satisfactory procedure. The freezing of samples is not an appropriate procedure for
samples requiring analysis of volatile substances or if samples contain cells or bacteria or microalgae, which
can fracture and lose cell constituents during the freezing process. Nevertheless, it is necessary to control the
freezing and thawing technique in order to return the sample to its initial equilibrium after thawing. In this case,
the use of plastic containers (for example polyvinyl chloride or polyethene) is strongly recommended. For
thawing of samples, see ISO 5667-16.
3.2.7 Filtration or centrifugation of samples
Suspended matter, sediment, algae and other micro-organisms may be removed, either at the time of taking
the sample or immediately afterwards, by filtering the sample through membrane filter material (e.g. paper,
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ISO 5667-3:2003(E)
polytetrafluoroethylene, glass) or by centrifuging. Filtration is, of course, not applicable if the membrane filter is
likely to retain one or more of the constituents to be analysed. It is equally essential that the membrane filter
assembly system not be a cause of contamination and be carefully washed before use, but in a manner
consistent with the final method of analysis.
Alternatively, the reason for filtering the sample may be to enable the proportion of soluble and insoluble forms
of an analyte to be determined (e.g. soluble and insoluble metal fractions).
Decanting the sample is not recommended as an alternative to filtration.
Membrane filters should be used with caution as various heavy metal compounds and organic material may
be adsorbed on the membrane filter surface, and soluble compounds (e.g. surfactants) within the membrane
filter can be leached out into the sample.
3.2.8 Addition of preservatives
Certain physical and chemical constituents can be stabilized by the addition of selective chemical compounds,
either directly to the sample after it has been taken, or beforehand, to the empty container.
Particular reagents, necessary for the specific preservation of certain constituents (e.g. the determination of
oxygen, total cyanides and sulfides) require the sample to be
...
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