SIST EN ISO 13164-3:2020

Water quality - Radon-222 - Part 3: Test method using emanometry (ISO 13164-3:2013)

ISO 13164-3:2013 specifies a test method for the determination of radon-222 activity concentration in a sample of water following its transfer from the aqueous phase to the air phase by degassing and its detection. It gives recommendations for rapid measurements performed within less than 1 h.
The radon-222 activity concentrations, which can be measured by this test method utilizing currently available instruments, range from 0,1 Bq l−1 to several hundred thousand becquerels per litre for a 100 ml test sample.
This test method is used successfully with drinking water samples. The laboratory is responsible for ensuring the validity of this test method for water samples of untested matrices.
This test method can be applied on field sites or in the laboratory.
Annexes A and B give indications on the necessary counting conditions to meet the required sensitivity for drinking water monitoring

Wasserbeschaffenheit - Radon-222 - Teil 2: Verfahren mittels Emanometrie (ISO 13164-3:2013)

Dieser Teil von ISO 13164 legt ein Verfahren zur Bestimmung der Radon 222 Aktivitätskonzentration in einer Wasserprobe fest, nachdem diese durch Entgasen von der wässrigen Phase in die Luftphase übergegangen ist und nachgewiesen wurde. Er gibt Empfehlungen für Schnellmessungen, die innerhalb von weniger als 1 h durchgeführt werden.
Die Radon 222 Aktivitätskonzentrationen, die mit diesem Verfahren unter Verwendung derzeit verfügbarer Instrumente gemessen werden können, reichen von 0,1 Bq l−1 bis zu mehreren hundert-tausend Becquerel je Liter für eine 100 ml Analysenprobe.
Dieses Verfahren wird erfolgreich bei Trinkwasserproben eingesetzt. Das Labor ist dafür verantwortlich, die Gültigkeit dieses Prüfverfahrens für Wasserproben ungeprüfter Matrizen sicherzustellen.
Dieses Prüfverfahren kann vor Ort oder im Labor angewendet werden.
Die Anhänge A und B enthalten Angaben zu den erforderlichen Zählbedingungen, um die für die Trinkwasser¬überwachung erforderliche Empfindlichkeit zu erreichen.

Qualité de l’eau - Radon 222 - Partie 3: Méthode d’essai par émanométrie (ISO 13164-3:2013)

L'ISO 13164-3:2013 spécifie une méthode d'essai permettant de déterminer l'activité volumique du radon 222 dans un échantillon d'eau après son transfert de la phase aqueuse vers la phase air par dégazage et sa détection. Elle donne des recommandations concernant des mesures rapides effectuées sur une période inférieure à 1 h.
Les valeurs d'activité volumique du radon 222, qui peuvent être mesurées par cette méthode d'essai à l'aide d'instruments actuellement disponibles, sont comprises entre 0,1 Bq l−1 et plusieurs centaines de milliers de becquerels par litre pour un échantillon d'essai de 100 ml.
Cette méthode d'essai est utilisée avec succès sur des échantillons d'eau potable. Il appartient au laboratoire de garantir la validité de cette méthode d'essai pour des échantillons d'eau provenant de matrices non soumises à essai.
Cette méthode d'essai peut être mise en oeuvre sur site ou en laboratoire.
Les annexes donnent des indications sur les conditions de comptage nécessaires pour obtenir la sensibilité requise pour la surveillance de l'eau potable.

Kakovost vode - Radon Rn-222 - 3. del: Preskusna metoda z emanometrijo (ISO 13164-3:2013)

General Information

• Status: Published
• Public Enquiry End Date: 01-Aug-2019
• Publication Date: 07-Apr-2020
• 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: 31-Mar-2020
• Due Date: 05-Jun-2020
• Completion Date: 08-Apr-2020
• Ref Project: EN ISO 13164-3:2020 - Water quality - Radon-222 - Part 3: Test method using emanometry (ISO 13164-3:2013)

Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN ISO 13164-3:2020
01-maj-2020
Kakovost vode - Radon Rn-222 - 3. del: Preskusna metoda z emanometrijo (ISO
13164-3:2013)

Water quality - Radon-222 - Part 3: Test method using emanometry (ISO 13164-3:2013)

Wasserbeschaffenheit - Radon-222 - Teil 2: Verfahren mittels Emanometrie (ISO 13164-

3:2013)

Qualité de l’eau - Radon 222 - Partie 3: Méthode d’essai par émanométrie (ISO 13164-

3:2013)
Ta slovenski standard je istoveten z: EN ISO 13164-3:2020
ICS:
13.060.60 Preiskava fizikalnih lastnosti Examination of physical
vode properties of water
17.240 Merjenje sevanja Radiation measurements
SIST EN ISO 13164-3:2020 en,fr,de

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

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SIST EN ISO 13164-3:2020
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SIST EN ISO 13164-3:2020
EN ISO 13164-3
EUROPEAN STANDARD
NORME EUROPÉENNE
February 2020
EUROPÄISCHE NORM
ICS 13.060.60; 17.240; 13.280
English Version
Water quality - Radon-222 - Part 3: Test method using
emanometry (ISO 13164-3:2013)

Qualité de l'eau - Radon 222 - Partie 3: Méthode d'essai Wasserbeschaffenheit - Radon-222 - Teil 2: Verfahren

par émanométrie (ISO 13164-3:2013) mittels Emanometrie (ISO 13164-3:2013)
This European Standard was approved by CEN on 6 October 2019.

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

Poland, Portugal, Republic of North Macedonia, 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

© 2020 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 13164-3:2020 E

worldwide for CEN national Members.
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SIST EN ISO 13164-3:2020
EN ISO 13164-3:2020 (E)
Contents Page

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

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SIST EN ISO 13164-3:2020
EN ISO 13164-3:2020 (E)
European foreword

The text of ISO 13164-3:2013 has been prepared by Technical Committee ISO/TC 147 "Water quality”

of the International Organization for Standardization (ISO) and has been taken over as EN ISO 13164-

3:2020 by 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 August 2020, and conflicting national standards shall

be withdrawn at the latest by August 2020.

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.

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, France, Germany, Greece, Hungary, Iceland,

Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of

North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the

United Kingdom.
Endorsement notice

The text of ISO 13164-3:2013 has been approved by CEN as EN ISO 13164-3:2020 without any

modification.
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SIST EN ISO 13164-3:2020
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SIST EN ISO 13164-3:2020
INTERNATIONAL ISO
STANDARD 13164-3
First edition
2013-09-01
Water quality — Radon-222 —
Part 3:
Test method using emanometry
Qualité de l’eau — Radon 222 —
Partie 3: Méthode d’essai par émanométrie
Reference number
ISO 13164-3:2013(E)
ISO 2013
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SIST EN ISO 13164-3:2020
ISO 13164-3:2013(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2013

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
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Tel. + 41 22 749 01 11
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Web www.iso.org
Published in Switzerland
ii © ISO 2013 – All rights reserved
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SIST EN ISO 13164-3:2020
ISO 13164-3:2013(E)
Contents Page

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

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

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

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

3 Terms, definitions and symbols ............................................................................................................................................................ 2

3.1 Terms and definitions ....................................................................................................................................................................... 2

3.2 Symbols ......................................................................................................................................................................................................... 2

4 Principle ........................................................................................................................................................................................................................ 3

5 Sampling ........................................................................................................................................................................................................................ 3

5.1 General requirement .......................................................................................................................................................................... 3

5.2 Sampling requirement ...................................................................................................................................................................... 3

5.3 Sample volume ........................................................................................................................................................................................ 3

5.4 Container characteristics ............................................................................................................................................................... 3

6 Transportation and storage ...................................................................................................................................................................... 4

7 Transfer of radon by degassing ............................................................................................................................................................. 4

7.1 Purpose .......................................................................................................................................................................................................... 4

7.2 Principle ........................................................................................................................................................................................................ 4

8 Detection ....................................................................................................................................................................................................................... 4

8.1 Objective ....................................................................................................................................................................................................... 4

8.2 Principle ........................................................................................................................................................................................................ 4

8.3 Silver-activated zinc sulfide ZnS(Ag) scintillation .................................................................................................... 4

8.4 Air ionization ............................................................................................................................................................................................ 5

8.5 Semiconductor (alpha-detection)........................................................................................................................................... 5

9 Quality assurance and quality control programme ......................................................................................................... 5

9.1 General ........................................................................................................................................................................................................... 5

9.2 Influence quantities ............................................................................................................................................................................ 5

9.3 Instrument verification.................................................................................................................................................................... 6

9.4 Method verification ............................................................................................................................................................................. 6

9.5 Demonstration of analyst capability .................................................................................................................................... 6

10 Expression of results ........................................................................................................................................................................................ 6

10.1 Activity concentration ...................................................................................................................................................................... 6

10.2 Standard uncertainty of the activity concentration ................................................................................................ 7

10.3 Decision threshold and detection limit .............................................................................................................................. 7

10.4 Confidence limits................................................................................................................................................................................... 7

11 Calibration .................................................................................................................................................................................................................. 7

12 Test report ................................................................................................................................................................................................................... 7

Annex A (informative) Examples of measurement methods using scintillation cells .......................................9

Annex B (informative) Example of a measurement method using an ionization chamber ......................17

Bibliography .............................................................................................................................................................................................................................23

© ISO 2013 – All rights reserved iii
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SIST EN ISO 13164-3:2020
ISO 13164-3:2013(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, 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.

The committee responsible for this document is ISO/TC 147, Water quality, Subcommittee SC 3,

Radioactivity measurements.

ISO 13164 consists of the following parts, under the general title Water quality — Radon-222:

— Part 1: General principles
— Part 2: Test method using gamma-ray spectrometry
— Part 3: Test method using emanometry
The following part is under preparation:
— Part 4: Test method using two-phase liquid scintillation counting
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SIST EN ISO 13164-3:2020
ISO 13164-3:2013(E)
Introduction

Radioactivity from several naturally occurring and human-made sources is present throughout the

environment. Thus, water bodies (surface waters, groundwaters, sea waters) can contain radionuclides

of natural and human-made origin.

— Natural radionuclides, including potassium-40, and those of the thorium and uranium decay series,

in particular radium-226, radium-228, uranium-234, uranium-238, lead-210, can be found in water

for natural reasons (e.g. desorption from the soil and wash-off by rain water) or releases from

technological processes involving naturally occurring radioactive materials (e.g. the mining and

processing of mineral sands or phosphate fertilizer production and use).

— Human-made radionuclides such as transuranium elements (americium, plutonium, neptunium,

curium), tritium, carbon-14, strontium-90 and gamma-emitting radionuclides can also be found in

natural waters as they can be authorized to be routinely released into the environment in small

quantities in the effluent discharged from nuclear fuel cycle facilities and following their used in

unsealed form in medicine or industry. They are also found in water due to the past fallout of the

explosion in the atmosphere of nuclear devices and the accidents at Chernobyl and Fukushima.

Drinking-water can thus contain radionuclides at activity concentration which could present a risk to

human health. In order to assess the quality of drinking-water (including mineral waters and spring

waters) with respect to its radionuclide content and to provide guidance on reducing health risks by

taking measures to decrease radionuclide activity concentrations, water resources (groundwater, river,

lake, sea, etc.) and drinking water are monitor for their radioactivity content as recommended by the

World Health Organization (WHO).

Standard test methods for radon-222 activity concentrations in water samples are needed by test

laboratories carrying out such measurements in fulfillment of national authority requirements.

Laboratories may have to obtain a specific accreditation for radionuclide measurement in drinking

water samples.

The radon activity concentration in surface water is very low, usually below 1 Bq l . In groundwater, the

−1 −1 −1

activity concentration varies from 1 Bq l up to 50 Bq l in sedimentary rock aquifers, from 10 Bq l

−1 −1 −1

up to 300 Bq l in wells, and from 100 Bq l up to 1 000 Bq l in crystalline rocks. The highest activity

concentrations are normally measured in rocks with high concentration of uranium (Reference [15]).

High variations in the activity concentrations of radon in aquifers have been observed. Even in a region

with relatively uniform rock types, some well water may exhibit radon activity concentration greatly

higher than the average value for the same region. Significant seasonal variations have also been

recorded (see Annex A).

Water may dissolve chemical substances as it passes from the soil surface to an aquifer or spring waters.

The water may pass through or remain for some time in rock, some formations of which may contain a

high concentration of natural radionuclides. Under favourable geochemical conditions, the water may

selectively dissolve some of these natural radionuclides.

Guidance on radon in drinking-water supplies provided by WHO in 2008 suggests that controls should be

implemented if the radon concentration of drinking-water for public water supplies exceeds 100 Bq l .

It also recommended that any new, especially public, drinking-water supply using groundwater should

be tested prior to being used for general consumption and that if the radon concentration exceeds

100 Bq l , treatment of the water source should be undertaken to reduce the radon levels to well below

that level (Reference [16]).

This International Standard is one of a series dealing with the measurement of the activity concentration

of radionuclides in water samples.

The origin of radon-222 and its short-lived decay products in water and other measurement methods

are described generally in ISO 13164-1.
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SIST EN ISO 13164-3:2020
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SIST EN ISO 13164-3:2020
INTERNATIONAL STANDARD ISO 13164-3:2013(E)
Water quality — Radon-222 —
Part 3:
Test method using emanometry

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 and to

ensure compliance with any national regulatory conditions.

IMPORTANT — It is absolutely essential that tests conducted in accordance with this document

be carried out by suitably qualified staff.
1 Scope

This part of ISO 13164 specifies a test method for the determination of radon-222 activity concentration

in a sample of water following its transfer from the aqueous phase to the air phase by degassing and its

detection. It gives recommendations for rapid measurements performed within less than 1 h.

The radon-222 activity concentrations, which can be measured by this test method utilizing currently

available instruments, range from 0,1 Bq l to several hundred thousand becquerels per litre for a

100 ml test sample.

This test method is used successfully with drinking water samples. The laboratory is responsible for

ensuring the validity of this test method for water samples of untested matrices.

This test method can be applied on field sites or in the laboratory.

Annexes A and B give indications on the necessary counting conditions to meet the required sensitivity

for drinking water monitoring.
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 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 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 13164-1, Water quality — Radon-222 — Part 1: General principles

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

IEC 61577-1, Radiation protection instrumentation — Radon and radon decay product measuring

instruments — Part 1: General principles
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SIST EN ISO 13164-3:2020
ISO 13164-3:2013(E)

IEC 61577-2, Radiation protection instrumentation — Radon and radon decay product measuring

instruments — Part 2: Specific requirements for radon measuring instruments
3 Terms, definitions and symbols
3.1 Terms and definitions

For the purposes of this document, the terms and definitions given in ISO 80000-10 and ISO 13164-1 apply.

3.2 Symbols

For the purposes of this document, the symbols defined in ISO 80000-10. ISO 13164-1, and the

following apply.

c measured radon activity concentration in the air of the measuring system after degassing,

in becquerels per cubic metre

c radon activity concentration in the air of the measuring system before degassing, in becque-

rels per cubic metre
c activity concentration of radon in water, in becquerels per litre
decision threshold, in becquerels per litre
detection limit, in becquerels per litre
c c lower and upper limits of the confidence interval, in becquerels per litre
A A
f conversion factor from cubic metre to litre: 0,001
f correction factor for the decay of radon during time interval t, dimensionless

k , k quantiles of the standardized normal distribution for the probabilities, p and q, respectively

p q
L Ostwald coefficient
T water temperature, in Celsius
t time interval between the sampling and the measurement, in seconds
U expanded uncertainty calculated by U = ku(c ) with k = 2
u(c ) standard uncertainty associated with the measurement result
V volume of test sample, in litres
V volume of air in the measurement system, in cubic metres
α, β probability of the error of the first and second kind, respectively
γ probability for the confidence interval of the activity concentration
λ decay constant of radon-222, in reciprocal second
Φ distribution function of the standardized normal distribution
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SIST EN ISO 13164-3:2020
ISO 13164-3:2013(E)
4 Principle

The determination of radon-222 activity concentration in water by degassing into the air phase is

based on the:

— collection of a representative sample of the water at time t in a suitable container;

— transfer of radon dissolved in the water to the air phase by degassing;

— detection of the alpha-radiation emitted by the radon or its solid decay products present in the air.

The radon activity concentration in the water is determined from the activity concentration in the air

phase, taking account of the Ostwald coefficient (see ISO 13164-1).
5 Sampling
5.1 General requirement

The sample shall be representative of the environment to be analysed at a given time.

5.2 Sampling requirement

The sampling shall be carried out in compliance with the conditions and techniques specified in

ISO 5667-1, ISO 5667-3, and ISO 13164-1. The temperature of the water shall be measured and recorded

during the sampling process.

Fill the container completely and fit the cap in such a way as to avoid the presence of air above the sample.

The container shall be filled in such a way as to avoid degassing the radon in the water sample. The

sampling techniques to be used vary according to the actual situation.

When the analytical laboratory is not in charge of sampling, the laboratory shall supply the container for

the measurement and specify the sampling procedure to the person carrying out the sampling operation.

It is recommended that several discrete samples be taken in case of problems arising in relation to the

sampling conditions or transportation of the samples.
5.3 Sample volume

Experience shows that a sample volume of at least 1 l is needed for the sample to be representative of

the environment to be analysed.

At least 1 l samples are recommended, but for the effective determination smaller test portions are used.

5.4 Container characteristics

The choice and preparation of a suitable container are important (see ISO 5667-3).

The container and cap used to contain the sample shall comply with the following requirements.

— They shall be made from inert materials, impermeable to radon, non-hydrophobic, and conductive

(in order not to adsorb radon and its decay products from the surrounding atmosphere).

— They shall be shock-proof.

The volume of the container should be compatible with the water volume required by the degassing

technique used.
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ISO 13164-3:2013(E)
6 Transportation and storage

During transportation and storage, the sample shall be maintained at a temperature below that of the

original water (but above 0 °C) until it is ready for analysis. The container shall be protected and tightly

sealed. The container shall be packed in an appropriate manner in order to prevent any leakage.

The period of transportation and storage prior to analysis shall be as short as possible given the half-

life of radon-222, the expected activity concentration, and the detection limit of the measurement

method to be used.

On arrival at the laboratory, the sample shall be maintained at a temperature below that of the original water

(but above 0 °C), if it cannot be analysed immediately. The sample shall be analysed as soon as possible.

Experience indicates that it is essential that the time between sampling and analysis not exceed 48 h.

7 Transfer of radon by degassing
7.1 Purpose

This technique is used to transfer the radon dissolved in the water into the air so that it can be detected

and measured in its gaseous state.
7.2 Principle

As the Ostwald coefficient of radon in water is fairly low, the dissolved radon degasses naturally into the

air with relatively slow kinetics (over a few hours) (see ISO 13164-1).
In order to accelerate the degassing process, several means may be used:
— shaking the sample;

— sparging radon-free air through the water sample using a fine air bubble to increase the air

exchange surface;
— decreasing the pressure in the air phase.

In order to improve the detection limit of the measurement method, it is necessary for the radon activity

concentration in the air used for the degassing process to be as low as possible and to be measured

before degassing the radon from the water.
8 Detection
8.1 Objective

The purpose of the detector is to quantify the alpha-radiation emitted by the radon and/or its solid

decay products that is directly related to the activity concentration of the radon in the air phase.

8.2 Principle
[1]
A number of detection techniques can be used (see ISO 11665-1 ).
8.3 Silver-activated zinc sulfide ZnS(Ag) scintillation

Some electrons in scintillating media, such as ZnS(Ag), have the particular feature of emitting photons

by returning to their ground state when they are excited by an alpha-particle. These emitted photons

can be detected using a photomultiplier.
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