SIST EN ISO 11704:2019

Water quality - Gross alpha and gross beta activity - Test method using liquid scintillation counting (ISO 11704:2018)

This document specifies a method for the determination of gross alpha and gross beta activity
concentration for alpha- and beta-emitting radionuclides using liquid scintillation counting (LSC).
The method is applicable to all types of waters with a dry residue of less than 5 g/l and when no
correction for colour quenching is necessary.
Gross alpha and gross beta activity measurement is not intended to give an absolute determination
of the activity concentration of all alpha- and beta-emitting radionuclides in a test sample, but is a
screening analysis to ensure particular reference levels of specific alpha and beta emitters have not
been exceeded. This type of determination is also known as gross alpha and beta index. Gross alpha
and beta analysis is not expected to be as accurate nor as precise as specific radionuclide analysis after
radiochemical separations.
The method covers non-volatile radionuclides below 80 °C, since some gaseous or volatile radionuclides
(e.g. radon and radioiodine) can be lost during the source preparation.
The method is applicable to test samples of drinking water, rain water, surface and ground water as
well as cooling water, industrial water, domestic and industrial waste water after proper sampling and
test sample preparation (filtration when necessary and taking into account the amount of dissolved
material in the water).
The method described in this document is applicable in the event of an emergency situation, because
the results can be obtained in less than 4 h by directly measuring water test samples without any
treatment.
It is the laboratory’s responsibility to ensure the suitability of this test method for the water
samples tested.

Wasserbeschaffenheit - Gesamt-Alpha- und Gesamt-Beta-Aktivität - Verfahren mit dem Flüssigszintillationszähler (ISO 11704:2018)

Diese Internationale Norm legt ein Verfahren zur Bestimmung der Gesamt-Alpha- und Gesamt-Beta-Aktivität durch alpha- und beta-emittierende Radionuklide mit dem Flüssigszintillationszähler (en: liquid scintillation counting, LSC) fest.
Das Verfahren ist anwendbar auf alle Wässer mit einem Trockenrückstand von weniger als 5 g/l und wenn keine Korrektur des Farbquench erforderlich ist.
Die Messung der Gesamt-Alpha- und Gesamt-Beta-Aktivität ist nicht dafür vorgesehen, eine absolute Bestimmung aller alpha- und beta-strahlenden Radionuklide in einer zu untersuchenden Probe zu leisten, aber als Screeningverfahren ist es geeignet sicherzustellen, das definierte Referenzniveaus spezifischer Alpha- und Beta-Strahler nicht überschritten werden. Diese Art der Bestimmung ist auch als Gesamt-Alpha- und Beta-Index bekannt. Die Gesamt-Alpha- und Beta-Analyse wird nicht genauso akkurat und präzise sein, wie die Analyse spezifischer Radionuklide nach radiochemischer Trennung.
Das Verfahren deckt nicht-flüchtige Radionuklide unter 80 °C ab, da einige gasförmige oder flüchtige Radionuklide (z. B. Radon und Radioiod) bei der Aufbereitung der Quelle verloren gehen können.
Das Verfahren ist auf Proben von Trinkwasser, Regenwasser, Oberflächen- und Grundwasser, sowie Kühlwasser, Prozesswasser, häusliches und gewerbliches Abwasser, nach geeigneter Probenahme, Probenbehandlung und Aufbereitung der Untersuchungsprobe (Filtration, falls erforderlich, und Berücksichtigung der im Wasser gelösten Bestandteile) anwendbar.
Das in dieser Norm beschriebene Verfahren ist bei Notfall-Situationen anwendbar, da die Ergebnisse in weniger als 4 h durch direktes Messen der Wasserproben ohne jegliche Vorbehandlung erhalten werden können.
Es liegt in der Verantwortung des Labors die Eignung dieses Prüfverfahrens für die zu prüfenden Wasserproben sicherzustellen.

Qualité de l'eau - Activités alpha globale et bêta globale - Méthode d'essai par comptage des scintillations en milieu liquide (ISO 11704:2018)

Le présent document spécifie une méthode de détermination des activités volumiques alpha globale et bêta globale pour des radionucléides émetteurs alpha et bêta par comptage des scintillations en milieu liquide.
La méthode est applicable à tous les types d'eau ayant un résidu sec inférieur à 5 g/l et lorsqu'aucune correction n'est nécessaire pour l'affaiblissement lumineux de couleur.
Le mesurage des activités alpha globale et bêta globale n'est pas destiné à fournir une détermination absolue de l'activité volumique de tous les radionucléides émetteurs alpha et bêta dans un échantillon pour essai; il s'agit plutôt d'une analyse de contrôle visant à s'assurer que des niveaux de référence donnés d'émetteurs alpha et bêta n'ont pas été dépassés. Ce type de déterminations est également connu sous le nom d'indices alpha et bêta. Il ne faut pas s'attendre à ce que l'analyse des activités alpha globale et bêta globale soit aussi précise, ni aussi juste, que l'analyse de radionucléides spécifiques après séparation radiochimique.
Cette méthode couvre les radionucléides non volatils en dessous de 80 °C, étant donné que certains radionucléides gazeux ou volatils (par exemple, le radon et l'iode radioactif) peuvent être perdus lors de la préparation de la solution source.
Cette méthode peut s'appliquer à des échantillons pour essai d'eau potable, d'eau de pluie, d'eau de surface et d'eau souterraine, ainsi que d'eau de refroidissement, d'eaux industrielles, d'eaux usées domestiques et industrielles, après avoir procédé comme il se doit au prélèvement et à la préparation des échantillons pour essai (en les filtrant lorsque cela s'avère nécessaire et en tenant compte de la quantité de matière dissoute dans l'eau).
La méthode décrite dans le présent document est applicable en cas de situation d'urgence, car les résultats peuvent être obtenus en moins de 4 h en mesurant directement les échantillons d'eau pour essai sans aucun traitement.
Il incombe au laboratoire de s'assurer de la pertinence de la présente méthode d'essai pour les échantillons d'eau soumis à essai.

Kakovost vode - Skupna alfa in skupna beta aktivnost - Preskusna metoda s štetjem s tekočinskim scintilatorjem (ISO 11704:2018)

Ta dokument določa metodo za določevanje koncentracije skupne alfa in skupne beta aktivnosti za alfa in beta oddajne radionuklide s štetjem s tekočinskim scintilatorjem (LSC).
Metoda se uporablja za vse vrste vod s suhim ostankom, manjšim od 5 g/l, pri katerih ni potreben
popravek za dušenje fluorescence.
Meritev skupne alfa in skupne beta aktivnosti ni namenjena absolutni določitvi koncentracije aktivnosti vseh alfa in beta oddajnih radionuklidov v preskusnem vzorcu, temveč je presejalna analiza, s katero se zagotovi, da določene referenčne ravni specifičnih alfa in beta oddajnikov
niso bile presežene. Ta vrsta določevanja se imenuje tudi skupni alfa in beta indeks. Ne pričakuje se, da bo skupna alfa
in skupna beta analiza enako točna in natančna kot specifična radionuklidna analiza po radiokemičnih separacijah.
Metoda zajema nehlapne radionuklide s temperaturo, nižjo od 80 °C, saj se lahko nekateri radionuklidi v plinastem stanju oziroma hlapni radionuklidi (npr. radon in radioaktivni jod) med pripravo virov izgubijo.
Metoda se uporablja za preskusne vzorce pitne vode, deževnice, površinske in podtalne vode
ter vode za hlajenje, industrijske vode, gospodinjske in industrijske odpadne vode po ustreznem vzorčenju in pripravi preskusnih vzorcev (filtracija, kadar je to potrebno, in upoštevanje količine raztopljenih snovi v vodi).
Metoda, opisana v tem dokumentu, se uporablja v izrednih razmerah, saj
je mogoče rezultate pridobiti v manj kot štirih urah z neposrednim merjenjem preskusnih vzorcev vode brez obdelave.
Laboratorij mora zagotoviti primernost te preskusne metode za vzorce vode, ki se preskušajo.

General Information

• Status: Published
• Public Enquiry End Date: 30-Sep-2017
• Publication Date: 11-Apr-2019
• ICS: 13.060.60 - Examination of physical properties of water
• ICS: 17.240 - Radiation measurements
• Technical Committee: KAV - Water quality
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 01-Feb-2019
• Due Date: 08-Apr-2019
• Completion Date: 12-Apr-2019
• Ref Project: EN ISO 11704:2018 - Water quality - Gross alpha and gross beta activity - Test method using liquid scintillation counting (ISO 11704:2018)

Relations

• Replaces: SIST EN ISO 11704:2015 - Water quality - Measurement of gross alpha and beta activity concentration in non-saline water - Liquid scintillation counting method (ISO 11704:2010)
• Effective Date: 01-May-2019
• Replaces: SIST ISO 11704:2013 - Water quality - Measurement of gross alpha and beta activity concentration in non-saline water - Liquid scintillation counting method
• Effective Date: 01-May-2019

Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN ISO 11704:2019
01-maj-2019
1DGRPHãþD
SIST EN ISO 11704:2015
SIST ISO 11704:2013
.DNRYRVWYRGH6NXSQDDOIDLQVNXSQDEHWDDNWLYQRVW3UHVNXVQDPHWRGDV
ãWHWMHPVWHNRþLQVNLPVFLQWLODWRUMHP,62
Water quality - Gross alpha and gross beta activity - Test method using liquid scintillation
counting (ISO 11704:2018)
Wasserbeschaffenheit - Gesamt-Alpha- und Gesamt-Beta-Aktivität - Verfahren mit dem
Flüssigszintillationszähler (ISO 11704:2018)
Qualité de l'eau - Activités alpha globale et bêta globale - Méthode d'essai par comptage
des scintillations en milieu liquide (ISO 11704:2018)
Ta slovenski standard je istoveten z: EN ISO 11704:2018
ICS:
13.060.60 Preiskava fizikalnih lastnosti Examination of physical
vode properties of water
17.240 Merjenje sevanja Radiation measurements
SIST EN ISO 11704:2019 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN ISO 11704:2019

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SIST EN ISO 11704:2019


EN ISO 11704
EUROPEAN STANDARD

NORME EUROPÉENNE

December 2018
EUROPÄISCHE NORM
ICS 13.060.60; 17.240 Supersedes EN ISO 11704:2015
English Version

Water quality - Gross alpha and gross beta activity - Test
method using liquid scintillation counting (ISO
11704:2018)
Qualité de l'eau - Activités alpha globale et bêta globale Wasserbeschaffenheit - Gesamt-Alpha- und Gesamt-
- Méthode d'essai par comptage des scintillations en Beta-Aktivität - Verfahren mit dem
milieu liquide (ISO 11704:2018) Flüssigszintillationszähler (ISO 11704:2018)
This European Standard was approved by CEN on 1 November 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 11704:2018 E
worldwide for CEN national Members.

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SIST EN ISO 11704:2019
EN ISO 11704:2018 (E)
Contents Page
European foreword . 3

2

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SIST EN ISO 11704:2019
EN ISO 11704:2018 (E)
European foreword
This document (EN ISO 11704:2018) 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 June 2019, and conflicting national standards shall be
withdrawn at the latest by June 2019.
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 11704:2015.
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 11704:2018 has been approved by CEN as EN ISO 11704:2018 without any modification.


3

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SIST EN ISO 11704:2019

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SIST EN ISO 11704:2019
INTERNATIONAL ISO
STANDARD 11704
Second edition
2018-11
Water quality — Gross alpha and gross
beta activity — Test method using
liquid scintillation counting
Qualité de l'eau — Activités alpha globale et bêta globale — Méthode
d'essai par comptage des scintillations en milieu liquide
Reference number
ISO 11704:2018(E)
©
ISO 2018

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SIST EN ISO 11704:2019
ISO 11704:2018(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 11704:2019
ISO 11704:2018(E)

Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms, definitions, symbols and abbreviated terms . 2
3.1 Terms and definitions . 2
3.2 Symbols and abbreviated terms. 2
4 Principle . 3
5 Reagents and equipment . 3
6 Sampling . 5
7 Procedure. 5
7.1 Direct counting. 5
7.2 Thermal preconcentration . 5
7.3 Sample preparation . 6
7.4 Liquid scintillation measurement . 6
7.4.1 Preparation of alpha and beta calibration sources . 6
7.4.2 Optimization of counting conditions . 6
7.4.3 Blank sample preparation and measurement . 7
7.4.4 Alpha and beta efficiencies . 7
7.4.5 Sample measurement . 8
8 Expression of results . 8
8.1 Calculation of activity per mass. 8
8.2 Standard uncertainty . 9
8.3 Decision threshold .10
8.4 Detection limit .10
8.5 Confidence limits.10
8.6 Quality control .11
9 Interference control .11
9.1 Contamination .11
9.2 Ingrowth of radon .11
9.3 Loss of polonium .11
10 Test report .11
Annex A (informative) Set-up parameters and validation data .13
Annex B (informative) Method performances under different conditions .17
Bibliography .18
© ISO 2018 – All rights reserved iii

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SIST EN ISO 11704:2019
ISO 11704:2018(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 of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO’s adherence to the
World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see www .iso
.org/iso/foreword .html.
This document was prepared by Technical Committee ISO/TC 147, Water quality, Subcommittee SC 3,
Radioactivity measurements.
This second edition cancels and replaces the first edition (ISO 11704:2010), which has been technically
revised. The main changes compared to the previous edition are as follows:
— 5.5.1 has been simplified;
— the application field of this document has been extended to emergency situations;
— slightly different counting conditions have been suggested;
— Annexes A and B have been added.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www .iso .org/members .html.
iv © ISO 2018 – All rights reserved

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SIST EN ISO 11704:2019
ISO 11704:2018(E)

Introduction
Radioactivity from several naturally-occurring and anthropogenic sources is present throughout
the environment. Thus, water bodies (e.g. surface waters, ground waters, sea waters) can contain
radionuclides of natural, human-made or both origins:
40 3 14
— natural radionuclides, including K, H, C, and those originating from the thorium and uranium
226 228 234 238 210 210
decay series, in particular Ra, Ra, U, U, Po and Pb, can be found in water for
natural reasons (e.g. desorption from the soil and washoff by rain water) or can be released from
technological processes involving naturally occurring radioactive materials (e.g. the mining and
processing of mineral sands or phosphate fertilizers production and use);
— human-made radionuclides, such as transuranium elements (americium, plutonium, neptunium,
3 14 90
curium), H, C, Sr and gamma emitting radionuclides can also be found in natural waters.
Small quantities of these radionuclides are discharged from nuclear fuel cycle facilities into the
environment as a result of authorized routine releases. Some of these radionuclides used for
medical and industrial applications are also released into the environment after use. Anthropogenic
radionuclides are also found in waters as a result of past fallout contaminations resulting from
the explosion in the atmosphere of nuclear devices and accidents, such as those that occurred in
Chernobyl and Fukushima.
Radionuclide activity concentration in water bodies can vary according to local geological
characteristics and climatic conditions and can be locally and temporally enhanced by releases from
[1]
nuclear installation during planned, existing and emergency exposure situations . Drinking-water
may thus contain radionuclides at activity concentrations, which could present a risk to human health.
The radionuclides present in liquid effluents are usually controlled before being discharged into
[2]
the environment and water bodies. Drinking waters are monitored for their radioactivity as
[3]
recommended by the World Health Organization (WHO) so that proper actions can be taken to ensure
that there is no adverse health effect to the public. Following these international recommendations,
national regulations usually specify radionuclide authorized concentration limits for liquid effluent
discharged to the environment and radionuclide guidance levels for water bodies and drinking waters
for planned, existing and emergency exposure situations. Compliance with these limits can be assessed
[4]
using measurement results with their associated uncertainties as specified by ISO/IEC Guide 98-3
[5]
and ISO 5667-20 .
Depending on the exposure situation, there are different limits and guidance levels that would result
in an action to reduce health risk. As an example, during a planned or existing situation, the WHO
guidelines for guidance level in drinking water is 0,5 Bq/l for gross alpha activity and 1 Bq/l for gross
beta activity.
NOTE The guidance level is the activity concentration with an intake of 2 l/d of drinking water for one year
that results in an effective dose of 0,1 mSv/a for members of the public. This is an effective dose that represents a
[3]
very low level of risk and which is not expected to give rise to any detectable adverse health effects .
Thus, the test method can be adapted so that the characteristic limits, decision threshold, detection
limit and uncertainties ensure that the radionuclide activity concentrations test results can be verified
to be below the guidance levels required by a national authority for either planned/existing situations
[6][7][8]
or for an emergency situation .
Usually, the test methods can be adjusted to measure the activity concentration of the radionuclide(s)
in either waste waters before storage or in liquid effluents before being discharged to the environment.
The test results will enable the plant/installation operator to verify that, before their discharge, waste
waters/liquid effluent radioactive activity concentrations do not exceed authorized limits.
The test method(s) described in this document may be used during planned, existing and emergency
exposure situations as well as for waste waters and liquid effluents with specific modifications that
could increase the overall uncertainty, detection limit and threshold.
© ISO 2018 – All rights reserved v

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SIST EN ISO 11704:2019
ISO 11704:2018(E)

The test method(s) may be used for water samples after proper sampling, sample handling and test
sample preparation (see the relevant part of the ISO 5667 series).
An International Standard on a test method of gross alpha and gross beta activity concentrations in
water samples is justified for test laboratories carrying out these measurements, required sometimes
by national authorities, as laboratories may have to obtain a specific accreditation for radionuclide
measurement in drinking water samples.
This document is one of a set of International Standards on test methods dealing with the measurement
of the activity concentration of radionuclides in water samples.
vi © ISO 2018 – All rights reserved

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SIST EN ISO 11704:2019
INTERNATIONAL STANDARD ISO 11704:2018(E)
Water quality — Gross alpha and gross beta activity — Test
method using liquid scintillation counting
WARNING — Persons using this document should be familiar with normal laboratory practice.
This document does not purport to address all of the safety problems, if any, associated with its
use. It is the responsibility of the user to establish appropriate safety and health practices.
IMPORTANT — It is absolutely essential that tests conducted according to this document be
carried out by suitably trained staff.
1 Scope
This document specifies a method for the determination of gross alpha and gross beta activity
concentration for alpha- and beta-emitting radionuclides using liquid scintillation counting (LSC).
The method is applicable to all types of waters with a dry residue of less than 5 g/l and when no
correction for colour quenching is necessary.
Gross alpha and gross beta activity measurement is not intended to give an absolute determination
of the activity concentration of all alpha- and beta-emitting radionuclides in a test sample, but is a
screening analysis to ensure particular reference levels of specific alpha and beta emitters have not
been exceeded. This type of determination is also known as gross alpha and beta index. Gross alpha
and beta analysis is not expected to be as accurate nor as precise as specific radionuclide analysis after
radiochemical separations.
The method covers non-volatile radionuclides below 80 °C, since some gaseous or volatile radionuclides
(e.g. radon and radioiodine) can be lost during the source preparation.
The method is applicable to test samples of drinking water, rain water, surface and ground water as
well as cooling water, industrial water, domestic and industrial waste water after proper sampling and
test sample preparation (filtration when necessary and taking into account the amount of dissolved
material in the water).
The method described in this document is applicable in the event of an emergency situation, because
the results can be obtained in less than 4 h by directly measuring water test samples without any
treatment.
It is the laboratory’s responsibility to ensure the suitability of this test method for the water
samples tested.
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 5667-1, Water quality — Sampling — Part 1: Guidance on the design of sampling programmes and
sampling techniques
ISO 5667-3, Water quality — Sampling — Part 3: Preservation and handling of water samples
ISO/IEC 17025, General requirements for the competence of testing and calibration laboratories
ISO 80000-10, Quantities and units — Part 10: Atomic and nuclear physics
© ISO 2018 – All rights reserved 1

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SIST EN ISO 11704:2019
ISO 11704:2018(E)

3 Terms, definitions, symbols and abbreviated terms
3.1 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 80000-10 apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https: //www .iso .org/obp
— IEC Electropedia: available at http: //www .electropedia .org/
3.2 Symbols and abbreviated terms
For the purposes of this document, the symbols and abbreviated terms defined in ISO 80000-10 and the
following apply.
−1
a , a Alpha and beta activity per mass Bq g
α β
−1
a* Decision threshold Bq g
−1
Detection limit Bq g
a#
−1
Lower and upper limits of the confidence interval Bq g
<>
aa,
A , A Activity of the alpha and beta emitter certified reference solution used Bq
α β
for the α and β calibration sources
m Mass of the test sample g
m Mass of initial sample subject to heating or possibly concentration g
1
m Mass of heated or concentrated sample g
2
m Mass of heated or concentrated sample transferred in the vial g
3
m , m Mass of alpha and beta emitters certified reference solutions, respectively g
Sα Sβ
−1
r , r Sample gross count rate, from the alpha and beta windows, respectively s
gα gβ
−1
r , r , r Blank count rate, from the alpha, beta and total windows, respectively s
0α 0β 0T
−1
r , r , Count rate of the alpha calibration source in the alpha, beta and total s
Sα,α Sα,β
r window
Sα,T
−1
r , r , Count rate of the beta calibration source in the alpha, beta and total s
Sβ,α Sβ,β
r window
Sβ,T
t Sample counting time s
g
t Blank counting time s
0
t , t Counting time of α and β calibration sources s
sα sβ
−1
u (a) Standard uncertainty associated with the measurement result Bq g
−1
U Expanded uncertainty, calculated from U = ku (a), where k = 1, 2 … Bq g
−1
Standard uncertainty of a as a function of its true value Bq g
  α
ua
()
α
2 © ISO 2018 – All rights reserved

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SIST EN ISO 11704:2019
ISO 11704:2018(E)

ε , ε Counting efficiency for alpha and beta, respectively —
α β
τ (χ ) Alpha interference — Fraction of counts observed in the beta window —
α α β
with respect to the total number of counts measured by the counter
when an alpha emitter is measured
τ (χ ) Beta interference — Fraction of counts observed in the alpha window —
β β α
with respect to the total number of counts measured by the counter
when a beta emitter is measured
4 Principle
Gross alpha and beta activity concentrations are determined by using liquid scintillation counting of a
water sample mixed with a scintillation cocktail.
Gross alpha and beta determinations are not absolute determinations of the sample radioactive
contents, but relative determinations referred to a specific alpha or beta emitter which constitutes the
standard calibration sources. These types of determinations are also known as the alpha and beta index
and are usually employed as screening parameters for first assessment of total radioactive content.
The aqueous sample is acidified using nitric acid and heated. Subsequently, water with low salt content
can be thermally concentrated by slow evaporation to improve the method sensitivity. An aliquot of
sample is transferred into a liquid scintillation vial with scintillation cocktail; scintillations from the
vial are then counted by equipment with an alpha and beta discrimination device.
The counter is previously optimized with respect to an alpha and beta discriminator setting and then
calibrated against alpha and beta emitter certified reference solutions. In data evaluation, no correction
for chemical quenching is applied, since the procedure is designed to provide samples with a relatively
constant quench level.
222
The method does not account for Rn and its short lived progeny and it is not suitable for
3
H measurement.
When suspended matter is present in significant quantities, a filtration step is required before
acidification.
5 Reagents and equipment
All reagents shall be of recognized analytical grade, except for the scintillation cocktail, and shall not
contain any detectable alpha and beta activity, except for the radioactive certified reference solutions.
5.1 Nitric acid, c(HNO ) = commercially available acid with mass fraction w(HNO ) = (65 to 70) %.
3 3
5.2 Water, ISO 3696, grade 3.
222
Deionized water can contain detectable amounts of Rn and short lived progeny. It is therefore
strongly recommended to boil water under vigorous stirring and let it stand for one day before use.
Alternatively, use nitrogen flushing for about 1 h for a 2 l sample.
5.3 Scintillation cocktail.
Commercially available scintillation cocktails suitable for alpha and beta discrimination
(e.g. diisopropylnaphthalene-based cocktails), water miscible.
5.4 Volatile organic solvents.
Methanol or ethanol.
© ISO 2018 – All rights reserved 3

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SIST EN ISO 11704:2019
ISO 11704:2018(E)

5.5 Certified reference solutions.
5.5.1 General
In general, the experimental parameters (efficiency, alpha and beta optimum discrimination) depend on
alpha and beta energies, thus the choice of alpha and beta emitter certified reference solutions depends
on knowledge of the type of radioactive contaminant likely to be present in the waters b
...

SLOVENSKI STANDARD
oSIST prEN ISO 11704:2017
01-september-2017
.DNRYRVWYRGH0HUMHQMHVNXSQHDOIDLQVNXSQHEHWDDNWLYQRVWL0HWRGDãWHWMDV
WHNRþLQVNLPVFLQWLODWRUMHP
Water quality - Gross alpha and gross beta activity - Test method using liquid scintillation
counting
Wasserbeschaffenheit - Bestimmung der Gesamt-Alpha- und Gesamt-Beta-Aktivität in
nicht-salzhaltigem Wasser - Verfahren mit dem Flüssigszintillationszähler
Qualité de l'eau - Activités alpha globale et bêta globale - Méthode d'essai par comptage
des scintillations en milieu liquide
Ta slovenski standard je istoveten z: prEN ISO 11704
ICS:
13.060.60 Preiskava fizikalnih lastnosti Examination of physical
vode properties of water
17.240 Merjenje sevanja Radiation measurements
oSIST prEN ISO 11704:2017 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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oSIST prEN ISO 11704:2017

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oSIST prEN ISO 11704:2017
DRAFT INTERNATIONAL STANDARD
ISO/DIS 11704
ISO/TC 147/SC 3 Secretariat: AFNOR
Voting begins on: Voting terminates on:
2017-07-13 2017-10-04
Water quality — Gross alpha and gross beta activity — Test
method using liquid scintillation counting
Qualité de l’eau — Activités alpha globale et bêta globale — Méthode d’essai par comptage des
scintillations en milieu liquide
ICS: 13.060.60; 17.240
THIS DOCUMENT IS A DRAFT CIRCULATED
This document is circulated as received from the committee secretariat.
FOR COMMENT AND APPROVAL. IT IS
THEREFORE SUBJECT TO CHANGE AND MAY
NOT BE REFERRED TO AS AN INTERNATIONAL
STANDARD UNTIL PUBLISHED AS SUCH.
IN ADDITION TO THEIR EVALUATION AS
ISO/CEN PARALLEL PROCESSING
BEING ACCEPTABLE FOR INDUSTRIAL,
TECHNOLOGICAL, COMMERCIAL AND
USER PURPOSES, DRAFT INTERNATIONAL
STANDARDS MAY ON OCCASION HAVE TO
BE CONSIDERED IN THE LIGHT OF THEIR
POTENTIAL TO BECOME STANDARDS TO
WHICH REFERENCE MAY BE MADE IN
Reference number
NATIONAL REGULATIONS.
ISO/DIS 11704:2017(E)
RECIPIENTS OF THIS DRAFT ARE INVITED
TO SUBMIT, WITH THEIR COMMENTS,
NOTIFICATION OF ANY RELEVANT PATENT
RIGHTS OF WHICH THEY ARE AWARE AND TO
©
PROVIDE SUPPORTING DOCUMENTATION. ISO 2017

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oSIST prEN ISO 11704:2017
ISO/DIS 11704:2017(E)

COPYRIGHT PROTECTED DOCUMENT
© ISO 2017, 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. [phone]
Fax [phone]
[e-mail]
www.iso.org
ii © ISO 2017 – All rights reserved

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oSIST prEN ISO 11704:2017
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Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Symbols, definitions and units . 2
4 Principle . 3
5 Reagents and equipment . 3
6 Sampling . 5
7 Procedure. 5
7.1 Direct counting. 5
7.2 Thermal preconcentration . 5
7.3 Sample preparation . 6
7.4 Liquid scintillation measurement . 6
7.4.1 Preparation of alpha and beta calibration sources . 6
7.4.2 Optimization of counting conditions . 6
7.4.3 Blank sample preparation and measurement . 7
7.4.4 Alpha and beta efficiencies . 7
7.4.5 Sample measurement . 8
8 Expression of results . 8
8.1 Calculation of activity per mass. 8
8.2 Standard uncertainty . 9
8.3 Decision threshold .10
8.4 Detection limit .10
8.5 Confidence limits.10
8.6 Quality control .11
9 Interference control .11
9.1 Contamination .11
9.2 Ingrowth of radon .11
9.3 Loss of polonium .11
10 Test report .11
Annex A (informative) Set-up parameters and validation data .13
Annex B (informative) Method performances under different conditions .17
Bibliography .18
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oSIST prEN ISO 11704:2017
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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. 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. 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 3,
Radioactivity measurements.
This second edition cancels and replaces the first edition (2010), [clause(s) / subclause(s) / table(s) /
figure(s) / annex(es)] of which [has / have] been technically revised.
iv © ISO 2017 – All rights reserved

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Introduction
Radioactivity from several naturally-occurring and anthropogenic sources is present throughout
the environment. Thus, water bodies (e.g. surface waters, ground waters, sea waters) can contain
radionuclides of natural, human-made, or both origins:
40 3 14
— natural radionuclides, including K, H, C, and those originating from the thorium and uranium
226 228 234 238 210 210
decay series, in particular Ra, Ra, U, U, Po and Pb can be found in water for
natural reasons (e.g. desorption from the soil and runoff by rain water) or can be released from
technological processes involving naturally occurring radioactive materials (e.g. the mining and
processing of mineral sands or phosphate fertilizers production and use);
— anthropogenic radionuclides such as transuranium elements (e.g. americium, plutonium, neptunium,
3 14 90
and curium), H, C, Sr, and some gamma emitting radionuclides can also be found in natural
waters. Small quantities of these radionuclides may be discharged from nuclear fuel cycle facilities
into the environment as the result of authorized routine releases. Some of these radionuclides
used for medical and industrial applications may also be released into the environment after use.
Anthropogenic radionuclides are also found in waters as a result of past fallout contaminations
resulting from the above ground detonation of nuclear devices and accidents such as those that
occurred in Chernobyl and Fukushima.
Radionuclide activity concentration in water bodies can vary according to local geological
characteristics and climatic conditions and can be locally and temporally enhanced by releases from
[1]
nuclear installation during planned, existing, and emergency exposure situations. Drinking-water
may thus contain radionuclides at activity concentrations which could present a risk to human health.
The radionuclides present in liquid effluents are usually controlled before being discharged into
[2]
the environment and water bodies. Drinking waters are monitored for their radioactivity as
[3]
recommended by the World Health Organization (WHO). Such control and monitoring can enable
to take proper actions to ensure that there is no adverse health effects to the public. Following these
international recommendations, radionuclide authorized concentration limits for liquid effluent
discharged to the environment and radionuclide guidance levels for waterbodies and drinking waters
are usually specified by national regulations for planned, existing, and emergency exposure situations.
Compliance with these limits can be assessed using measurement results with their associated
[4]
uncertainties as requested by ISO/IEC Guide 98-3 and ISO 5667-20.
Depending of the exposure situation, the limits and guidance levels that would result in an action to
1)
reduce health risk differ. As an example, during planned or existing situation, the WHO guidance for
screening levels in drinking water is 0,5 Bq/l for gross alpha activity and 1 Bq/l for gross beta activity.
2)
In the event of a nuclear emergency, the WHO Codex Guideline Levels mentioned that the activity
concentration might not be greater than N Bq/l for radionuclide XX.
b
Thus, the test method may need to be adjusted depending if it is applied for either a planned-existing
or an emergency situation since during emergency situations a large number of samples needs to
be rapidly characterized. The test methods could be adapted so that its performance in term of
characteristic limits, decision threshold, and detection limit, and the uncertainties ensure that the
1) Note 1: The guidance level is the activity concentration with an intake of 2 l/d of drinking water for 1 year, that
results in an effective dose of 0,1 mSv/a for members of the public, an effective dose that represents a very low level
of risk that is not expected to give rise to any detectable adverse health effect [3].
2) Note 2: The Codex guidelines levels (GLs) apply to radionuclides contained in foods destined for human
consumption and traded internationally, which have been contaminated following a nuclear or radiological
emergency. These guideline levels apply to food after reconstitution or as prepared for consumption, i.e., not to dried
or concentrated foods, and are based on an intervention exemption level of 1 mSv in a year .document containing
values of activity concentration in foods, including liquid beverages, that would result in an effective dose of 1
mSv/a for members of the public (infant and adult). The guideline levels have been checked against age-dependent
ingestion dose coefficients defined as committed effective doses per unit intake for each radionuclide, which are
taken from the “International Basic Safety Standards” [5]. The Codex GLs are included in the General Standard for
Contaminants and Toxins in Food and Feeds [6].
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radionuclide activity concentration test results permit the verification that they are below the guidance
levels required by national authority for either planned-existing situations or an emergency situation.
[6][7][8]
Usually, the test methods can be adjusted to measure the activity concentration of the radionuclide(s)
in either wastewaters before storage or in liquid effluents before being discharged to the environment.
The test results will enable the plant/installation operator to comply with national regulations in
verifying that before their discharge, wastewaters/liquid effluent radioactive activity concentrations
are lower than the authorized limits.
The test method(s) described in this standard may be used during planned, existing and emergency
exposure situations as well as for wastewaters and liquid effluents with specific modifications that
could increase the overall uncertainty, detection limit, and threshold.
The test method(s) may be used for water samples after proper sampling, sample handling, and test
sample preparation (see the ad hoc part of ISO 5667).
An international standard on a test method of gross alpha and gross beta activity concentrations in
water samples is justified for test laboratories carrying out these measurements, and may be required
by national authorities, as laboratories may have to obtain a specific accreditation for radionuclide
measurement in drinking water samples.
This document is one of a set of International Standards on test methods dealing with the measurement
of the activity concentration of radionuclides in water samples.
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oSIST prEN ISO 11704:2017
DRAFT INTERNATIONAL STANDARD ISO/DIS 11704:2017(E)
Water quality — Gross alpha and gross beta activity — Test
method using liquid scintillation counting
WARNING — Persons using this International Standard should be familiar with normal
laboratory practice. This standard does not purport to address all of the safety problems, if any,
associated with its use. It is the responsibility of the user to establish appropriate safety and
health practices and to ensure compliance with any national regulatory conditions.
IMPORTANT — It is absolutely essential that tests conducted according to this International
Standard be carried out by suitably trained staff.
1 Scope
This International Standard specifies a method for the determination of gross alpha and gross beta
activity concentration for alpha- and beta-emitting radionuclides using liquid scintillation counting (LSC).
The method is applicable to all types of waters with a dry residue of less than 5 g/l and when no
correction for colour quenching is necessary.
Gross alpha and gross beta activity measurement is not intended to give an absolute determination
of the activity concentration of all alpha and beta emitting radionuclides in a test sample, but is a
screening analysis to ensure particular reference levels of specific alpha and beta emitters have not
been exceeded. This type of determination is also known as gross alpha and beta index. Gross alpha
and beta analysis is not expected to be as accurate nor as precise as specific radionuclide analysis after
radiochemical separations.
The method covers non-volatile radionuclides below 80 °C, since some gaseous or volatile radionuclides
(e.g. radon and radioiodine) may be lost during the source preparation.
The method is applicable to test sample of drinking water, rainwater, surface and ground water as
well as cooling water, industrial water, domestic and industrial wastewater after proper sampling and
test sample preparation (filtration when necessary and taking into account the amount of dissolved
material in the water).
The method described in this standard is applicable in the event of an emergency situation, because
the results can be obtained in less than 4 h by directly measuring water test samples without any
treatment.
It is the laboratory’s responsibility to ensure the suitability of this test method for the water
samples tested.
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 5667-1, Water quality — Sampling — Part 1: Guidance on the design of sampling programmes and
sampling techniques
ISO 5667-3, Water quality — Sampling — Part 3: Guidance on the preservation and handling of water samples
ISO/IEC 17025, General requirements for the competence of testing and calibration laboratories
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ISO 11929, Determination of the characteristic limits (decision threshold, detection limit and limits of the
confidence interval) for measurements of ionizing radiation — Fundamentals and application
ISO 80000-10, Quantities and units — Part 10: Atomic and nuclear physics
3 Symbols, definitions and units
For the purposes of this document, the definitions, symbols and abbreviations defined in ISO 80000-10,
and the following apply.
-1
a , a Alpha and beta activity per mass Bq g
α β
-1
a* Decision threshold Bq g
-1
#
Detection limit Bq g
   a
-1
 Lower and upper limits of the confidence interval Bq g
   aa,
A , A Activity of the alpha and beta emitter certified reference solution used Bq
α β
for the α and β calibration sources
m Mass of the test sample g
m Mass of initial sample subject to heating or possibly concentration g
1
m Mass of heated or concentrated sample g
2
m Mass of heated or concentrated sample transferred in the vial g
3
m , m Mass of alpha and beta emitters certified reference solutions, respectively g
Sα Sβ
-1
r , r Sample gross count rate, from the alpha and beta windows, respectively s
gα gβ
-1
r , r , r Blank count rate, from the alpha, beta and total windows, respectively s
0α 0β 0T
-1
r , r , r Count rate of the alpha calibration source in the alpha, beta and s
Sα,α Sα,β Sα,T
total window
-1
r , r , r Count rate of the beta calibration source in the alpha, beta and s
Sβ,α Sβ,β Sβ,T
total window
t Sample counting time s
g
t Blank counting time s
0
t , t Counting time of α and β calibration sources s
sα sβ
-1
u (a) Standard uncertainty associated with the measurement result Bq g
-1
U Expanded uncertainty, calculated from U = ku (a), where k = 1, 2 … Bq g
-1
Standard uncertainty of a as a function of its true value Bq g
   ua()
α
α
2 © ISO 2017 – All rights reserved

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ε , ε Counting efficiency for alpha and beta, respectively —
α β
Alpha interference — Fraction of counts observed in the beta window —
   τχ()
α αβ
with respect to the total number of counts measured by the counter
when an alpha emitter is measured
Beta interference — Fraction of counts observed in the alpha window —
   τχ()
ββ α
with respect to the total number of counts measured by the counter
when a beta emitter is measured
4 Principle
Gross alpha and beta activity concentrations are determined by using liquid scintillation counting of a
water sample mixed with a scintillation cocktail.
Gross alpha and beta determinations are not absolute determinations of the sample radioactive
contents, but relative determinations referred to a specific alpha or beta emitter which constitutes the
standard calibration sources. These types of determinations are also known as the alpha and beta index
and are usually employed as screening parameters for first assessment of total radioactive content.
The aqueous sample is acidified using nitric acid and heated. Subsequently, water with low salt content
can be thermally concentrated by slow evaporation to improve the method sensitivity. An aliquot of
sample is transferred into a liquid scintillation vial with scintillation cocktail; scintillations from the
vial are then counted by equipment with an alpha and beta discrimination device.
The counter is previously optimized with respect to an alpha and beta discriminator setting and then
calibrated against alpha and beta emitter certified reference solutions. In data evaluation, no correction
for chemical quenching is applied, since the procedure is designed to provide samples with a constant
quenching level.
222 3
The method does not account for Rn and its daughters of short half-life and it is not suitable for H
measurement.
When suspended matter is present in significant quantities, a filtration step is required before
acidification.
5 Reagents and equipment
All reagents shall be of recognized analytical grade, except for the scintillation cocktail, and shall not
contain any detectable alpha and beta activity, except for the radioactive certified reference solutions.
5.1 Nitric acid, c(HNO ) = 15,8 mol/l, ρ = 1,42 g/ml, mass fraction w(HNO ) = 70 %.
3 3
5.2 Water, ISO 3696, grade 3.
222
Deionized water can contain detectable amounts of Rn and short half-life decay products. It is
therefore strongly recommended to boil water under vigorous stirring and let it stand for one day
before use. Alternatively, use nitrogen flushing for about 1 h for a 2 l sample.
5.3 Scintillation cocktail
Commercially available scintillation cocktails suitable for alpha and beta discrimination (e.g.
diisopropylnaphthalene-based cocktails).
5.4 Volatile organic solvents
Methanol or ethanol.
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5.5 Certified reference solutions
5.5.1 General
A calibration laboratory establishes traceability of its own calibration sources and measuring
instruments to the International System of Units (SI) by means of an unbroken chain of calibrations
or comparisons linking them to relevant certified reference solutions of the SI units of measurement.
The link to the SI units may be achieved with respect to national certified reference materials. These
may be primary realizations of the SI units, or agreed representations of SI units based on fundamental
physical constants, or they may be secondary materials which are materials certified by another
national metrology institute. When using external calibration services, traceability of measurement
shall be assured by the use of calibration services from laboratories that can demonstrate competence,
measurement capability, and traceability. The calibration certificates issued by these laboratories
shall contain the measurement results, including the measurement uncertainty and/or statement of
compliance with an identified metrological specification.
NOTE Calibration laboratories fulfilling the requirements of this International Standard are considered
to be competent. A calibration certificate bearing an accreditation body logo from a calibration laboratory
accredited to this International Standard, for the calibration concerned, is sufficient evidence of traceability of
the calibration data reported.
In general, the experimental parameters (efficiency, alpha and beta optimum discrimination) depend on
alpha and beta energies, thus the choice of alpha and beta emitter certified reference solutions depends
on knowledge of the type of radioactive contaminant likely to be present in the waters being tested (see
[9] [10]
ISO 9696 and Reference ).
5.5.2 Alpha emitter certified reference solution
The alpha emitter certified reference solution shall not contain any unexpected detectable alpha and
beta activity.
236
U is a convenient choice when waters are checked for their natural radioactivity content, as its energy
226
is close to the most widespread natural radionuclides (e.g. uranium and thorium isotopes, Ra) and
it is commercially available without decay products of short half-life. The supplier can supply details of
the absence of any decay product.
241 239
Am is commonly used when artificial radionuclide contamination is suspected. Pu can be used as
well in such circumstances.
5.5.2 Beta emitter certified reference solution
The beta emitter certified reference solution shall not contain alpha-emitting radioisotopes.
90 90 40
A Sr and Y mixture or K are commonly used. A potassium solution for atomic absorption
spectrometry has one arguable advantage, in that its specific activity can be calculated from established
physical constants and isotopic abundance data which are independent of the calibration procedures of
a particular organization.
5.6 Equipment
5
...