SIST EN ISO 13164-4:2020
(Main)Water quality - Radon-222 - Part 4: Test method using two-phase liquid scintillation counting (ISO 13164-4:2015)
Water quality - Radon-222 - Part 4: Test method using two-phase liquid scintillation counting (ISO 13164-4:2015)
ISO 13164-4:2015 describes a test method for the determination of radon-222 (222Rn) activity concentration in non-saline waters by extraction and liquid scintillation counting.
The radon-222 activity concentrations, which can be measured by this test method utilizing currently available instruments, are at least above 0,5 Bq l−1 for a 10 ml test sample and a measuring time of 1 h.
This test method can be used successfully with drinking water samples and it is the responsibility of the laboratory to ensure the validity of this test method for water samples of untested matrices.
Annex A gives indication on the necessary counting conditions to meet the required detection limits for drinking water monitoring.
Wasserbeschaffenheit - Radon-222 - Teil 4: Verfahren mittels zweistufiger Flüssigszintillationszählung (ISO 13164-4:2015)
Dieser Teil von ISO 13164 beschreibt ein Verfahren zur Bestimmung der Aktivitätskonzentration von Radon 222 (222Rn) in nicht salzhaltigen Gewässern durch Extraktion und Flüssigszintillationszählverfahren.
Die Radon 222 Aktivitätskonzentrationen, die mit diesem Verfahren unter Verwendung derzeit verfügbarer Instrumente gemessen werden können, liegen mindestens über 0,5 Bq l−1 für eine 10 ml Analysenprobe und einen Messzeitraum von 1 h.
Dieses Verfahren kann mit Trinkwasserproben erfolgreich angewendet werden, und es liegt in der Verantwortung des Labors, die Gültigkeit dieses Verfahrens für Wasserproben nicht geprüfter Matrizen sicherzustellen.
Anhang A enthält Angaben zu den erforderlichen Zählbedingungen, um die für die Trinkwasserüberwachung erforderlichen Nachweisgrenzen zu erreichen.
Qualité de l’eau - Radon 222 - Partie 4: Méthode d’essai par comptage des scintillations en Milieu liquide à deux phases (ISO 13164-4:2015)
L'ISO 13164-4:2015 spécifie une méthode d'essai permettant de déterminer l'activité volumique du radon 222 (222Ra) dans des eaux non salines par extraction et comptage des scintillations en milieu liquide.
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 au moins supérieures à 0,5 Bq l−1 pour une prise d'essai de 10 ml et un temps de comptage de 1 h.
Cette méthode d'essai peut être utilisée avec succès sur des échantillons d'eau potable et il appartient au laboratoire de s'assurer de la validité de cette méthode d'essai pour des échantillons d'eau provenant de matrices non testées.
L'Annexe A donne une indication sur les conditions de comptage nécessaires pour obtenir les limites de détection requises pour la surveillance de l'eau potable.
Kakovost vode - Radon Rn-222 - 4. del: Preskusna metoda s štetjem z dvofaznim tekočinskim scintilatorjem (ISO 13164-4:2015)
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
SIST EN ISO 13164-4:2020
01-maj-2020
Kakovost vode - Radon Rn-222 - 4. del: Preskusna metoda s štetjem z dvofaznim
tekočinskim scintilatorjem (ISO 13164-4:2015)
Water quality - Radon-222 - Part 4: Test method using two-phase liquid scintillation
counting (ISO 13164-4:2015)Wasserbeschaffenheit - Radon-222 - Teil 4: Verfahren mittels zweistufiger
Flüssigszintillationszählung (ISO 13164-4:2015)
Qualité de l’eau - Radon 222 - Partie 4: Méthode d’essai par comptage des scintillations
en Milieu liquide à deux phases (ISO 13164-4:2015)Ta slovenski standard je istoveten z: EN ISO 13164-4:2020
ICS:
13.060.60 Preiskava fizikalnih lastnosti Examination of physical
vode properties of water
17.240 Merjenje sevanja Radiation measurements
SIST EN ISO 13164-4:2020 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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SIST EN ISO 13164-4:2020
EN ISO 13164-4
EUROPEAN STANDARD
NORME EUROPÉENNE
February 2020
EUROPÄISCHE NORM
ICS 13.060.60; 17.240; 13.280
English Version
Water quality - Radon-222 - Part 4: Test method using
two-phase liquid scintillation counting (ISO 13164-
4:2015)
Qualité de l'eau - Radon 222 - Partie 4: Méthode d'essai Wasserbeschaffenheit - Radon-222 - Teil 4: Verfahren
par comptage des scintillations en milieu liquide à mittels zweistufiger Flüssigszintillationszählung (ISO
deux phases (ISO 13164-4:2015) 13164-4:2015)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 13164-4:2020 E
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SIST EN ISO 13164-4:2020
EN ISO 13164-4:2020 (E)
Contents Page
European foreword ....................................................................................................................................................... 3
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EN ISO 13164-4:2020 (E)
European foreword
The text of ISO 13164-4:2015 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-
4:2020 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 13164-4:2015 has been approved by CEN as EN ISO 13164-4:2020 without any
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SIST EN ISO 13164-4:2020
INTERNATIONAL ISO
STANDARD 13164-4
First edition
2015-06-15
Water quality — Radon-222 —
Part 4:
Test method using two-phase liquid
scintillation counting
Qualité de l’eau — Radon 222 —
Partie 4: Méthode d’essai par comptage des scintillations en milieu
liquide à deux phases
Reference number
ISO 13164-4:2015(E)
ISO 2015
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SIST EN ISO 13164-4:2020
ISO 13164-4:2015(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2015, 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. +41 22 749 01 11
Fax +41 22 749 09 47
copyright@iso.org
www.iso.org
ii © ISO 2015 – All rights reserved
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ISO 13164-4:2015(E)
Contents Page
Foreword ........................................................................................................................................................................................................................................iv
Introduction ..................................................................................................................................................................................................................................v
1 Scope ................................................................................................................................................................................................................................. 1
2 Normative references ...................................................................................................................................................................................... 1
3 Terms and definitions and symbols.................................................................................................................................................. 1
3.1 Terms and definitions ....................................................................................................................................................................... 1
3.2 Symbols and abbreviated terms............................................................................................................................................... 1
4 Principle ........................................................................................................................................................................................................................ 2
5 Reagents and apparatus ............................................................................................................................................................................... 2
5.1 Reagents........................................................................................................................................................................................................ 2
5.2 Apparatus .................................................................................................................................................................................................... 3
6 Sampling ........................................................................................................................................................................................................................ 3
6.1 General ........................................................................................................................................................................................................... 3
6.2 Sampling with source preparation “on site” .................................................................................................................. 3
6.3 Sampling without “on site” source preparation ......................................................................................................... 4
7 Instrument set up and calibration ..................................................................................................................................................... 4
7.1 Preparation of calibration sources ........................................................................................................................................ 4
7.2 Optimization of counting conditions ................................................................................................................................... 4
7.3 Detection efficiency............................................................................................................................................................................. 4
7.4 Blank sample preparation and measurement .............................................................................................................. 5
8 Sample preparation and measurement ........................................................................................................................................ 5
9 Expression of results ........................................................................................................................................................................................ 6
9.1 Calculation of activity per unit of mass .............................................................................................................................. 6
9.2 Standard uncertainty ......................................................................................................................................................................... 6
9.3 Decision threshold ............................................................................................................................................................................... 6
9.4 Detection limit ......................................................................................................................................................................................... 7
9.5 Confidence limits................................................................................................................................................................................... 7
9.6 Calculations using the activity concentration .............................................................................................................. 7
10 Interference control .......................................................................................................................................................................................... 8
11 Quality control ........................................................................................................................................................................................................ 8
12 Test report ................................................................................................................................................................................................................... 8
Annex A (informative) Set-up parameters and validation data ................................................................................................ 9
Bibliography .............................................................................................................................................................................................................................12
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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 (see www.iso.org/directives).Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www.iso.org/patents).Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.For an explanation on the 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.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
— Part 4: Test method using two-phase liquid scintillation counting
iv © ISO 2015 – All rights reserved
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Introduction
Radioactivity from several naturally occurring and anthropogenic sources is present throughout the
environment. Thus, water bodies (surface waters, ground waters, sea waters) can contain radionuclides
of natural or human-made origin, or both.— Natural radionuclides, including potassium-40, and those originating from the thorium and uranium
decay series, in particular radium-226, radium-228, uranium-234, uranium-238, and lead-210, can
be found in water for natural reasons (e.g. desorption from the soil and wash-off 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 fertilizer production and use).
— Human-made radionuclides such as transuranium elements (americium, plutonium, neptunium,
curium), tritium, carbon-14, strontium-90, and some gamma-emitting radionuclides can also be
found in natural waters as a result of authorized routine releases into the environment in small
quantities in the effluent discharged from nuclear fuel cycle facilities. They are also released into
the environment following their use in unsealed form in medicine or industrial applications. They
are also found in the water as a result of past fallout resulting from explosion in the atmosphere of
nuclear devices and accidents such as those that occurred in 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 monitored for their radioactivity content as recommended by the
World Health Organization (WHO) and may be required by some national authorities.
Standard test methods for radon-222 activity concentrations in water samples are needed by test
laboratories carrying out such measurements in fulfilment 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 −1activity concentration varies from 1 Bq l up to 50 Bq l in sedimentary rock aquifers, from 10 Bq l
−1 −1 −1up 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 (see Reference [9]).
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 can exhibit radon activity concentration greatly
higher than the average value for the same region. Significant seasonal variations have also been
recorded (see ISO 13164-1:2013, Annex A).Water can dissolve chemical substances as it passes from the soil surface to an aquifer or spring waters.
The water can pass through or remain for some time in rock, some formations of which can contain a
high concentration of natural radionuclides. Under favourable geochemical conditions, the water can
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 is 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 (see Reference [10]).This part of ISO 13164 is one of the 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.© ISO 2015 – All rights reserved v
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SIST EN ISO 13164-4:2020
INTERNATIONAL STANDARD ISO 13164-4:2015(E)
Water quality — Radon-222 —
Part 4:
Test method using two-phase liquid scintillation counting
WARNING — Persons using this part of ISO 13164 should be familiar with normal laboratory
practice. This part of ISO 13164 does not purport to address all of the safety issues, 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 part of
ISO 13164 be carried out by suitably qualified staff.1 Scope
222
This part of ISO 13164 describes a test method for the determination of radon-222 ( Rn) activity
concentration in non-saline waters by extraction and liquid scintillation counting.
The radon-222 activity concentrations, which can be measured by this test method utilizing currently
available instruments, are at least above 0,5 Bq l for a 10 ml test sample and a measuring time of 1 h.
This test method can be used successfully with drinking water samples and it is the responsibility of the
laboratory to ensure the validity of this test method for water samples of untested matrices.
Annex A gives indication on the necessary counting conditions to meet the required detection limits for
drinking water monitoring.2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and are
indispensable for its application. 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 methodsISO 80000-10, Quantities and units — Part 10: Atomic and nuclear physics
ISO/IEC 17025, General requirements for the competence of testing and calibration laboratories
3 Terms and definitions and symbols3.1 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 80000-10 apply.
3.2 Symbols and abbreviated termsFor the purposes of this document, symbols and abbreviations defined in ISO 80000-10, as well as the
following symbols, apply.a massic activity of the sample, in becquerels per gram
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a massic activity of the standard solution at the measuring time, in becquerels per gram
a* decision threshold for the total massic activity, in becquerels per grama detection limit for the total massic activity, in becquerels per gram
⊲ ⊳
a , a lower and upper limits of the confidence interval, in becquerels per gram
c activity concentration, in becquerels per litre
m mass of the test sample, in grams
m mass of standard solution used for the preparation of the counting standard, in grams
r blank sample count rate, in reciprocal secondsr sample gross count rate, in reciprocal seconds
r count rate of the standard in the counting window (alpha + beta), in reciprocal seconds
t blank sample counting time, in secondst test sample counting time, in seconds
t calibration sample counting time, in seconds
u(a) standard uncertainty associated with the measurement result; in becquerels per gram
U expanded uncertainty, calculated using U = ku(a), with k = 2, in becquerels per gram
w coefficient equal to 1/(ε m), in reciprocal gramε total efficiency
ρ density, in grams per litre
4 Principle
222
Rn is extracted from aqueous solution by means of a scintillation cocktail not miscible with water
(without emulsifier) inside the scintillation vial and counted as the equilibrium with its short lived
[1] [2] [3] [4]decay products is reached.
The aqueous sample is drawn by the mean of a gas-tight syringe from inside the water volume (i.e. well
below surface) to avoid radon losses during sampling and transferred into a scintillation vial containing
the desired amount of scintillation cocktail. For the same reason, the water sample is injected below
the cocktail surface. The vial is tightly capped, shaken and kept for 3 h preferably in the dark and at
controlled temperature. The sample is then counted by a liquid scintillation counter. Either total counts
222(alpha + beta) or alpha only counts are considered. In these conditions Rn and its short lived progeny
218 214 214 214( Po, Pb, Bi, and Po) are measured.
5 Reagents and apparatus
5.1 Reagents
All reagents shall be of recognized analytical grade and, except for 5.1.4, shall not contain any detectable
alpha and beta activity.2 © ISO 2015 – All rights reserved
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5.1.1 Water, distilled or deionized, complying with ISO 3696, grade 3.
222
Deionized water can contain detectable amounts of Rn and short lived daughters. It is, therefore,
strongly recommended that water be boiled under vigorous stirring and allowed to stand for 1 day
before use. Otherwise, purge it with nitrogen for about 1 h for 2 l.5.1.2 Scintillation cocktail, commercially available scintillation cocktails, not water miscible.
5.1.3 Ethanol, 95 %.5.1.4 Radium standard solution.
226
Ra standard solutions shall be provided with calibration certificates containing at least the activity
concentration, measurement uncertainty and/or statement of compliance with an identified metrological
specification.5.2 Apparatus
5.2.1 Balance.
5.2.2 Wide-mouth glass sample bottles, volume from 500 ml to 1 l.
5.2.3 Wide-mouth Erlenmeyer flask, volume from 500 ml to 1 l.
5.2.4 Gas-tight syringe.
5.2.5 Liquid scintillation counter, preferably with thermostated counting chamber and preferably
ultra-low level counter to achieve better detection limits.5.2.6 Polyethylene scintillation vials, PTFE coated, volume 20 ml.
5.2.7 Glass scintillation vials, low potassium glass, volume 20 ml.
NOTE PTFE coated polyethylene vials are the best choice since they prevent both the diffusion of the cocktail
into the wall of the vial, radon loss and the absorption of radon from the external environment. Glass vials exhibit
a considerably higher background due to potassium-40 content.6 Sampling
6.1 General
Since radon is easily desorbed from water sample, care should be taken to avoid analyte losses during
the sampling.6.2 Sampling with source preparation “on site”
Attach a plastic tube to a faucet with a proper fitting. Insert the other end of the tube in a wide-mouth
Erlenmeyer flask (5.2.3). Allow a steady water stream to get out and overflow the flask for approximately
2 min. Adjust the flux to avoid turbulence, bubbles, and empty volumes both in the tube and in the flask.
Draw the water sample aliquot with a gas-tight syringe (5.2.4) inserting the needle well below the
surface.© ISO 2015 – All rights reserved 3
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6.3 Sampling without “on site” source preparation
Attach a plastic tube to a faucet with a proper fitting. Insert the other end of the tube in a wide-
mouth borosilicate bottle (5.2.2). Allow a steady water stream to flow out and overflow the bottle for
approximately 2 min. Adjust flux to avoid turbulence, bubbles, and empty volumes both in the tube and
in the bottle. Gently extract the tube and screw tightly the cap avoiding any air head space. A one-litre
bottle is generally suitable for the sampling.The sample should be transported into laboratory and analysed possibly within 48 h. The sample should
neither be frozen nor overheated. Its preservation at temperature not higher than that of the sampled
water is recommended.7 Instrument set up and calibration
7.1 Preparation of calibration sources
226
Transfer an accurately known amount m of the Ra standard solution (5.1.4) into a 20 ml scintillation
vial (5.2.6 or 5.2.7). Let the massic activity at the measuring time be a . Dilute with laboratory water
(5.1.1) (see ISO 3696) to the previously chosen mass (e.g. 10 g). Add the scintillation cocktail (5.1.2).
Store the sample for at least 30 days to allow the achievement of secular equilibrium.
222A standard solution of Rn can also be used if available. In this case, it can be counted 3 h after its
preparation. Since Ra-226 is not extracted into the organic phase, its alpha emission would not affect
detection efficiency calibration for Rn-222.7.2 Optimization of counting conditions
Both alpha + beta counting or alpha counting using alpha-beta discrimination can be used (see
manufacturer instructions).When using alpha-beta discrimination, both alpha background and efficiency are usually lower; in
practice it is found that a much lower detection limit can be achieved.Set the counting window so that the channels affected by photo and chemo-luminescence are excluded.
NOTE Since no water is present in the scintillation cocktail phase, the quenching is low and constant thus no
quenching correction is needed.7.3 Detection efficiency
Let the counting rate be r for the counts of the calibration source in the counting window (alpha + beta).
Determine the detection efficiency:rr−
S 0
ε = (1)
am⋅
Acceptance limits for efficiency should be defined.
NOTE ε includes both counting and extraction efficiency. Usual values are in the range of 400 % to 500 %
222 218 214 214 214( Rn, Po, Po alpha emissions and Pb, Bi beta emissions). If using alpha only counting, a lower ε value
(≤ 300 %) is to be expected.It is advisable to check the method linearity. The efficiency should be assessed using calibration sources
whose activities should cover the whole working range.A more accurate estimate of efficiency can be obtained by preparing and measuring a sufficient number
of calibration sources.4 © ISO 2015 – All rights reserved
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