SIST EN ISO 19581:2020
(Main)Measurement of radioactivity - Gamma emitting radionuclides - Rapid screening method using scintillation detector gamma-ray spectrometry (ISO 19581:2017)
Measurement of radioactivity - Gamma emitting radionuclides - Rapid screening method using scintillation detector gamma-ray spectrometry (ISO 19581:2017)
ISO 19581 specifies a screening test method to quantify rapidly the activity concentration of gamma-emitting radionuclides, such as 131I, 132Te, 134Cs and 137Cs, in solid or liquid test samples using gamma-ray spectrometry with lower resolution scintillation detectors as compared with the HPGe detectors (see IEC 61563).
This test method can be used for the measurement of any potentially contaminated environmental matrices (including soil), food and feed samples as well as industrial materials or products that have been properly conditioned. Sample preparation techniques used in the screening method are not specified in ISO 19581, since special sample preparation techniques other than simple machining (cutting, grinding, etc.) should not be required. Although the sampling procedure is of utmost importance in the case of the measurement of radioactivity in samples, it is out of scope of ISO 19581; other international standards for sampling procedures that can be used in combination with ISO 19581 are available (see References [1],[2],[3],[4],[5],[6]).
The test method applies to the measurement of gamma-emitting radionuclides such as 131I, 134Cs and 137Cs. Using sample sizes of 0,5 l to 1,0 l in a Marinelli beaker and a counting time of 5 min to 20 min, decision threshold of 10 Bq·kg−1 can be achievable using a commercially available scintillation spectrometer [e.g. thallium activated sodium iodine (NaI(Tl)) spectrometer 2" ϕ × 2" detector size, 7 % resolution (FWHM) at 662 keV, 30 mm lead shield thickness].
This test method also can be performed in a "makeshift" laboratory or even outside a testing laboratory on samples directly measured in the field where they were collected.
During a nuclear or radiological emergency, this test method enables a rapid measurement of the sample activity concentration of potentially contaminated samples to check against operational intervention levels (OILs) set up by decision makers that would trigger a predetermined emergency response to reduce existing radiation risks[12].
Due to the uncertainty associated with the results obtained with this test method, test samples requiring more accurate test results can be measured using high-purity germanium (HPGe) detectors gamma-ray spectrometry in a testing laboratory, following appropriate preparation of the test samples[7][8].
ISO 19581 does not contain criteria to establish the activity concentration of OILs.
Bestimmung der Radioaktivität - Gammastrahlung emittierende Radionuklide - Schnellverfahren mit Szintillationsdetektor und Gammaspektrometrie (ISO 19581:2017)
Dieses Dokument legt ein Screening-Messverfahren zur schnellen Erfassung der spezifischen Aktivität von Gammastrahlung emittierenden Radionukliden fest, wie 131I, 132Te, 134Cs und 137Cs in festen oder flüssigen Proben. Dies erfolgt unter Verwendung der Gammaspektrometrie mit Szintillationsdetektoren mit niedrigerer Auflösung als HPGe-Detektoren (siehe IEC 61563).
Dieses Messverfahren kann für die Messung von allen möglichen kontaminierten Umweltproben (einschließ-lich Erdboden), Nahrungsmittel- und Futtermittelproben als auch Industrieprodukten oder anderen Produkten verwendet werden, sofern diese entsprechend konditioniert sind. Die in dem Screening-Messverfahren ver-wendeten Probenvorbereitungstechniken sind in diesem Dokument nicht beschrieben, da andere Probenvor-bereitungstechniken als einfache Verfahren (zerkleinern, mahlen usw.) nicht erforderlich sein sollten. Obwohl das Probenahmeverfahren von größter Bedeutung bei der Messung der Radioaktivität in Proben ist, ist es nicht Gegenstand dieses Dokuments; andere Internationale Normen zur Probenahme sind verfüg¬bar und können in Kombination mit diesem Dokument verwendet werden (siehe Literaturhinweise [1], [2], [3], [4], [5], [6]).
Das Messverfahren gilt für die Messung von Gammastrahlung emittierenden Radionukliden wie 131I, 134Cs und 137Cs. Mit kommerziell erhältlichen Szintillationsspektrometern kann eine Erkennungsgrenze von 10 Bq·kg–1 bei Verwendung von 0,5-l- bis 1,0-l-Proben in Marinelli-Bechern und einer Messzeit von 5 min bis 20 min erreicht werden [beispielsweise mit Thallium-dotierten Natriumiodid(NaI(Tl)-Spektrometer mit einer Kristallgröße von 2 Zoll Durchmesser und 2 Zoll Länge, 7 % Auflösung (FWHM) bei 662 keV, 30 mm Bleiab-schirmung].
Dieses Screening-Messverfahren kann in einem „provisorischen“ Labor oder außerhalb von Prüflaboren direkt im Feld, wo die Proben gesammelt werden, angewendet werden.
Während einer nuklearen oder radiologischen Notfallsituation ermöglicht dieses Prüfverfahren eine schnelle Messung der spezifischen Probenaktivität von möglicherweise kontaminierten Proben, um sie mit Richtwer-ten (en: operational intervention levels; OILs) zu vergleichen, die von Entscheidungsträgern aufgestellt wur-den, und eine vorbestimmte Notfallschutzreaktion auslösen würde, um das existierende Strahlenrisiko zu reduzieren [12].
Aufgrund der mit dem Messergebnis verknüpften Messunsicherheit, die mit diesem Prüfverfahren erreicht wird, können Prüfproben, die ein genaueres Messergebnis erfordern, mit HPGe-Gammaspektrometrie in einem Prüflabor mit geeigneter Probenvorbereitung gemessen werden [7], [8].
Dieses Dokument enthält keine Kriterien zum Aufstellen der Richtwerte für die spezifische Aktivität.
Mesurage de la radioactivité - Radionucléides émetteurs gamma - Méthode d'essai de dépistage par spectrométrie gamma utilisant des détecteurs par scintillation (ISO 19581:2017)
Le présent document spécifie une méthode d'essai de présélection pour quantifier rapidement l'activité volumique des radionucléides émetteurs gamma tels que l'131I, le 132Te, le 134Cs et le 137Cs, dans des échantillons pour essai solides ou liquides par spectrométrie gamma à l'aide de détecteurs à scintillation de résolution inférieure à celle des détecteurs HPGe (voir l'IEC 61563).
Cette méthode d'essai peut être utilisée pour mesurer les matrices environnementales potentiellement contaminées (y compris le sol), les échantillons d'aliment ainsi que les matériaux ou produits industriels adéquatement conditionnés. Les techniques de préparation des échantillons utilisées dans la méthode de présélection ne sont pas spécifiées dans le présent document car, hormis un simple traitement (découpage, broyage, etc.), aucune technique spéciale de préparation des échantillons n'est requise. Même si le mode opératoire d'échantillonnage est capital dans le cas du mesurage de la radioactivité dans les échantillons, il ne fait pas partie du domaine d'application du présent document; d'autres normes internationales relatives aux modes opératoires d'échantillonnage utilisables avec le présent document sont disponibles (voir les Références [1],[2],[3],[4],[5],[6]).
La méthode d'essai s'applique au mesurage des radionucléides émetteurs gamma tels que l'131I, le 134Cs et le 137Cs. En utilisant des volumes d'échantillon de 0,5 l à 1,0 l dans un bécher Marinelli et une durée de comptage de 5 min à 20 min, un seuil de décision de 10 Bq kg−1 peut être obtenu à l'aide d'un spectromètre à scintillations disponible dans le commerce [par exemple spectromètre équipé d'un cristal d'iodure de sodium activé au thallium (NaI(Tl)) ayant un détecteur d'une dimension de 2" ϕ × 2", d'une résolution de 7 % (FWHM) à 662 keV, d'une épaisseur de plomb de 30 mm].
Cette méthode d'essai peut également être effectuée dans un laboratoire «improvisé» voire à l'extérieur d'un laboratoire d'essai sur des échantillons directement mesurés sur leur lieu de prélèvement.
Dans une situation d'urgence nucléaire ou radiologique, cette méthode d'essai permet de mesurer rapidement l'activité volumique d'échantillons potentiellement contaminés pour la comparer aux niveaux opérationnels d'intervention (NOI) définis par les responsables et qui devraient provoquer une intervention d'urgence prédéterminée pour réduire les risques liés aux rayonnements existants[12].
En raison de l'incertitude associée aux résultats obtenus avec cette méthode d'essai, les échantillons pour essai nécessitant des résultats d'essai plus précis peuvent être mesurés par spectrométrie gamma à détecteurs en germanium à haute pureté (HPGe) dans un laboratoire d'essai, après une préparation appropriée des échantillons pour essai[7][8].
Le présent document ne comprend aucun critère permettant d'établir l'activité volumique des NOI.
Merjenje radioaktivnosti - Radionuklidi, ki sevajo gama žarke - Metoda hitrega presejanja z uporabo scintilacijskega zaznavala in gama spektrometrije (ISO 19581:2017)
General Information
Standards Content (Sample)
SLOVENSKI STANDARD
SIST EN ISO 19581:2020
01-maj-2020
Merjenje radioaktivnosti - Radionuklidi, ki sevajo gama žarke - Metoda hitrega
presejanja z uporabo scintilacijskega zaznavala in gama spektrometrije (ISO
19581:2017)
Measurement of radioactivity - Gamma emitting radionuclides - Rapid screening method
using scintillation detector gamma-ray spectrometry (ISO 19581:2017)
Bestimmung der Radioaktivität - Gammastrahlung emittierende Radionuklide -
Schnellverfahren mit Szintillationsdetektor und Gammaspektrometrie (ISO 19581:2017)
Mesurage de la radioactivité - Radionucléides émetteurs gamma - Méthode d'essai de
dépistage par spectrométrie gamma utilisant des détecteurs par scintillation (ISO
19581:2017)
Ta slovenski standard je istoveten z: EN ISO 19581:2020
ICS:
17.240 Merjenje sevanja Radiation measurements
SIST EN ISO 19581:2020 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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SIST EN ISO 19581:2020
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SIST EN ISO 19581:2020
EN ISO 19581
EUROPEAN STANDARD
NORME EUROPÉENNE
February 2020
EUROPÄISCHE NORM
ICS 17.240
English Version
Measurement of radioactivity - Gamma emitting
radionuclides - Rapid screening method using scintillation
detector gamma-ray spectrometry (ISO 19581:2017)
Mesurage de la radioactivité - Radionucléides Bestimmung der Radioaktivität - Gammastrahlung
émetteurs gamma - Méthode d'essai de dépistage par emittierende Radionuklide - Schnellverfahren mit
spectrométrie gamma utilisant des détecteurs par Szintillationsdetektor und Gammaspektrometrie (ISO
scintillation (ISO 19581:2017) 19581:2017)
This European Standard was approved by CEN on 6 January 2020.
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 19581:2020 E
worldwide for CEN national Members.
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SIST EN ISO 19581:2020
EN ISO 19581:2020 (E)
Contents Page
European foreword . 3
2
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SIST EN ISO 19581:2020
EN ISO 19581:2020 (E)
European foreword
The text of ISO 19581:2017 has been prepared by Technical Committee ISO/TC 85 "Nuclear energy,
nuclear technologies, and radiological protection” of the International Organization for Standardization
(ISO) and has been taken over as EN ISO 19581:2020 by Technical Committee CEN/TC 430 “Nuclear
energy, nuclear technologies, and radiological protection” the secretariat of which is held by AFNOR.
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 19581:2017 has been approved by CEN as EN ISO 19581:2020 without any modification.
3
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SIST EN ISO 19581:2020
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SIST EN ISO 19581:2020
INTERNATIONAL ISO
STANDARD 19581
First edition
2017-10
Measurement of radioactivity —
Gamma emitting radionuclides
— Rapid screening method using
scintillation detector gamma-ray
spectrometry
Mesurage de la radioactivité — Radionucléides émetteurs gamma —
Méthode d'essai de dépistage par spectrométrie gamma utilisant des
détecteurs par scintillation
Reference number
ISO 19581:2017(E)
©
ISO 2017
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SIST EN ISO 19581:2020
ISO 19581:2017(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
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Fax +41 22 749 09 47
copyright@iso.org
www.iso.org
ii © ISO 2017 – All rights reserved
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SIST EN ISO 19581:2020
ISO 19581:2017(E)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 2
4 Symbols and units . 3
5 Principle . 4
6 Apparatus . 6
7 Sample container . 7
8 Procedure. 7
8.1 Packaging of samples for measuring purposes . 7
8.2 Calibration . 8
8.2.1 General. 8
8.2.2 Reference source . 8
8.2.3 Check source . 8
8.2.4 Energy calibration . 8
8.2.5 Detection efficiency calibration . 9
8.3 Validation of the screening level .11
8.4 Screening procedure .11
8.4.1 Total spectrum counting / Single channel analyser counting .11
8.4.2 Multichannel analyser counting .12
8.4.3 Effect of sample density .13
9 Test report .13
Annex A (informative) Example of application of ISO 19581 for radio-caesium screening .15
Bibliography .18
© ISO 2017 – All rights reserved iii
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SIST EN ISO 19581:2020
ISO 19581:2017(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www.iso.org/patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation on the meaning of ISO specific terms and expressions related to conformity assessment,
as well as information about ISO's adherence to the World Trade Organization (WTO) principles in the
Technical Barriers to Trade (TBT) see the following URL: www.iso.org/iso/foreword.html.
This document was prepared by Technical committee ISO/TC 85, Nuclear Energy, nuclear technologies,
and radiological protection, Subcommittee SC 2, Radiological protection.
iv © ISO 2017 – All rights reserved
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SIST EN ISO 19581:2020
ISO 19581:2017(E)
Introduction
Everyone is exposed to natural radiation. The natural sources of radiation are cosmic rays and
naturally occurring radioactive substances which exist in the earth and within the human body. Human
activities involving the use of radiation and radioactive substances add to the radiation exposure
from this natural exposure. Some of those activities, such as the mining and use of ores containing
naturally-occurring radioactive materials (NORM) and the production of energy by burning coal that
contains such substances, simply enhance the exposure from natural radiation sources. Nuclear power
plants and other nuclear installations use radioactive materials and produce radioactive effluent and
waste during operation and on their decommissioning. The use of radioactive materials in industry,
agriculture and research is expanding around the globe.
All these human activities give rise to radiation exposures that are only a small fraction of the global
average level of natural exposure. The medical use of radiation is the largest and a growing man-made
source of radiation exposure in developed countries. It includes diagnostic radiology, radiotherapy,
nuclear medicine and interventional radiology.
Radiation exposure also occurs as a result of occupational activities. It is incurred by workers in
industry, medicine and research using radiation or radioactive substances, as well as by passengers
and crew during air travel and for astronauts. The average level of occupational exposures is generally
[11]
below the global average level of natural radiation exposure .
As uses of radiation increase, so do the potential health risk and the public's concerns. Thus, all these
exposures are regularly assessed in order to
a) improve the understanding of global levels and temporal trends of public and worker exposure
b) to evaluate the components of exposure so as to provide a measure of their relative importance, and
c) to identify emerging issues that may warrant more attention and study.
While doses to workers are mostly directly measured, doses to the public are usually assessed by
indirect methods using radioactivity measurements results performed on various sources: waste,
effluent and/or environmental samples.
To ensure that the data obtained from radioactivity monitoring programs support their intended use, it
is essential that the stakeholders (for example, nuclear site operators, regulatory and local authorities)
agree on appropriate methods and procedures for obtaining representative samples and then
handling, storing, preparing and measuring the test samples. A assessment of the overall measurement
uncertainty needs also to be carried out systematically. As reliable, comparable and ‘fit for purpose’
data are an essential requirement for any public health decision based on radioactivity measurements,
international standards of tested and validated radionuclide test methods are an important tool for
the production of such measurement results. The application of standards serves also to guarantee
comparability over time of the test results and between different testing laboratories. Laboratories
apply them to demonstrate their technical qualifications and to successfully complete proficiency
tests during interlaboratory comparison, two prerequisites for obtaining national accreditation.
Today, over a hundred international standards, prepared by Technical Committees of the International
Standardization Organization, including those produced by ISO/TC85, and the International
Electrotechnical Commission (IEC), are available for application by testing laboratories to measure the
main radionuclides.
Generic standards help testing laboratories to manage the measurement process by setting out the
general requirements and methods to calibrate and validate techniques. These standards underpin
specific standards which describe the test methods to be performed by staff, for example, for different
types of sample. The specific standards cover test methods for:
40 3 14
— Naturally-occurring radionuclides (including K, H, C and those originating from the thorium
226 228 234 238 210
and uranium decay series, in particular Ra, Ra, U, U, Pb) which can be found in
materials from natural sources or can be released from technological processes involving naturally
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SIST EN ISO 19581:2020
ISO 19581:2017(E)
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,
3 14 90
and curium), H, C, Sr and gamma emitting radionuclides found in waste, liquid and gaseous
effluent, in environmental matrices (water, air, soil, biota) and food and feed as a result of authorized
releases into the environment and of fallout resulting from the explosion in the atmosphere of
nuclear devices and accidents, such as those that occurred in Chernobyl and Fukushima.
Environmental materials, including foodstuffs, thus may contain radionuclides at activity
concentrations which could present a risk to human health. In order to assess the potential human
exposure to radioactivity and to provide guidance on reducing health risks by taking measures to
decrease radionuclide activity concentrations, the environment and foodstuffs are routinely monitored
for radioactivity content as recommended by the World Health Organization (WHO). Gamma-emitting
radionuclides are usually quantified in environmental and food samples by gamma-ray spectrometry
using High Purity Germanium (HPGe) gamma-ray spectrometry. Following a nuclear accident, a
screening approach based on rapid test methods is recommended to help the decision makers to decide
whether activity concentrations in environmental samples, feed and food samples are above or below
[12]
operational intervention levels (OILs) that are specifically set up to manage nuclear and radiological
emergency. During nuclear emergency response, these default radionuclide specific OILs for food, milk
and water concentrations from laboratory analysis would be used to measure the effectiveness of
[12][13]
protective actions and contribute to determining any further actions required .
In 1989, following the Chernobyl accident, the first version of the Codex Guideline Levels (GLs) for
Radionuclides in Foods Contaminated Following a Nuclear or Radiological Emergency (in the following
referred to as “Codex GLs”) was adopted. The Codex GLs were reviewed in 2006 and are included
[14][15]
in the General Standard for Contaminants and Toxins in Food and Feeds . During a nuclear
106 106 131
emergency situation, the Codex GLs for gamma-emitting radionuclides such as Ru/ Rh and I is
−1 60 103 137 134 144 −1
100 Bq·kg ; the GL for Co, Ru, Cs and Cs, Ce is higher at 1000 Bq·kg but a lower limit of
−1
100 Bq·kg still applies for foods for infants. Default radionuclide specific OILs for food, milk and water
concentrations from laboratory analysis set up by FAO, IAEA, ILO, OECD/NEA, PAHO, OCHA, WHO were
[16]
recently revised .
NOTE The Codex GLs are the activity concentration in foods that would result in an effective dose of
1 mSv/year for members of the Public (infant and adult) in accordance with the most recent recommendations
of the International Commission on Radiological Protection (ICRP) considering that 550 kg of food is consumed
per year by an adult and 200 kg of food and milk is consumed per year by an infant, with 10 % of the diet is of
imported food, all of which is contaminated giving an import to production factor of 0,1. For convenience the
GL values were rounded, and radionuclides with ingestion dose coefficients of similar magnitudes grouped
and given similar GLs values. However, separate GLs were derived for infants and adults due to differences in
radionuclide absorption, metabolism and sensitivity to radiation.
Emergency preparedness should include planning for the implementation of optimized test methods
that can provide rapid estimates of activity concentration to be checked against OILs. Thus, an
international standard on a screening method using Gamma-Ray Spectrometry is justified for use
by testing laboratories carrying out measurements of gamma-emitting radionuclides during an
emergency situation. Such laboratories are intended to obtain a specific accreditation for radionuclide
measurement in environmental and/or food samples.
This document describes, after proper sampling, sample handling and preparation, a screening method
to quantify rapidly the activity concentration of iodine and caesium in environmental, feedstuffs and
foodstuffs samples using scintillation spectrometer during an emergency situation.
This document is one of a set of generic international standards on measurement of radioactivity.
vi © ISO 2017 – All rights reserved
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SIST EN ISO 19581:2020
INTERNATIONAL STANDARD ISO 19581:2017(E)
Measurement of radioactivity — Gamma emitting
radionuclides — Rapid screening method using
scintillation detector gamma-ray spectrometry
WARNING — Persons using this document should be familiar with normal testing 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 document be
carried out by suitably trained staff.
1 Scope
This document specifies a screening test method to quantify rapidly the activity concentration of
131 132 134 137
gamma-emitting radionuclides, such as I, Te, Cs and Cs, in solid or liquid test samples using
gamma-ray spectrometry with lower resolution scintillation detectors as compared with the HPGe
detectors (see IEC 61563).
This test method can be used for the measurement of any potentially contaminated environmental
matrices (including soil), food and feed samples as well as industrial materials or products that
have been properly conditioned. Sample preparation techniques used in the screening method
are not specified in this document, since special sample preparation techniques other than simple
machining (cutting, grinding, etc.) should not be required. Although the sampling procedure is of
utmost importance in the case of the measurement of radioactivity in samples, it is out of scope of this
document; other international standards for sampling procedures that can be used in combination with
this document are available (see References [1],[2],[3],[4],[5],[6]).
131 134
The test method applies to the measurement of gamma-emitting radionuclides such as I, Cs
137
and Cs. Using sample sizes of 0,5 l to 1,0 l in a Marinelli beaker and a counting time of 5 min to
−1
20 min, decision threshold of 10 Bq·kg can be achievable using a commercially available scintillation
spectrometer [e.g. thallium activated sodium iodine (NaI(Tl)) spectrometer 2” ϕ × 2” detector size, 7 %
resolution (FWHM) at 662 keV, 30 mm lead shield thickness].
This test method also can be performed in a “makeshift” laboratory or even outside a testing laboratory
on samples directly measured in the field where they were collected.
During a nuclear or radiological emergency, this test method enables a rapid measurement of the sample
activity concentration of potentially contaminated samples to check against operational intervention
levels (OILs) set up by decision makers that would trigger a predetermined emergency response to
[12]
reduce existing radiation risks .
Due to the uncertainty associated with the results obtained with this test method, test samples requiring
more accurate test results can be measured using high-purity germanium (HPGe) detectors gamma-ray
[7][8]
spectrometry in a testing laboratory, following appropriate preparation of the test samples .
This document does not contain criteria to establish the activity concentration of OILs.
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 2017 – All rights reserved 1
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SIST EN ISO 19581:2020
ISO 19581:2017(E)
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
ISO/IEC 17025, General requirements for the competence of testing and calibration laboratories
IEC 61453, Nuclear instrumentation — Scintillation gamma ray detector systems for the assay of
radionuclides – Calibration and routine tests
3 Terms and definitions
For the purposes of this document, the terms, definitions, and the symbols and abbreviations given in
ISO 80000-10 and the following apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at http://www.iso.org/obp
— IEC Electropedia: available at http://www.electropedia.org/
3.1
blank sample
sample, liquid or solid, with very low to no activity for radiation of the same type and region of interest,
with a mass and a composition as close as possible to those of the test sample
3.2
emergency
non-routine situation that necessitates prompt action, primarily to mitigate a hazard or adverse
consequences for human life and health, property and the environment
[SOURCE: IAEA safety glossary 2016 Rev.]
Note 1 to entry: This includes nuclear and radiological emergencies and conventional emergencies such as
fires, release of hazardous chemicals, storms or earthquakes. It includes situations for which prompt action is
[12]
warranted to mitigate the effects of a perceived hazard .
3.3
operational intervention level
OIL
set level of a measurable quantity that corresponds to a generic criterion
[SOURCE: IAEA safety glossary 2016 Rev. Mod]
Note 1 to entry: OILs are calculated levels, measured by instruments or determined by laboratory analysis,
that corresponds to an intervention level or action level. These are typically expressed in terms of dose rates
or of activity of radioactive material released, time integrated air activity concentrations, ground or surface
concentrations, or activity concentrations of radionuclides in environmental, food or water samples. OILs are
used immediately and directly (without further assessment) to determine the appropriate protective actions on
[12]
the basis of an environmental measurement .
2 © ISO 2017 – All rights reserved
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SIST EN ISO 19581:2020
ISO 19581:2017(E)
3.4
reference level
level of dose, risk or activity
concentration above which it is not appropriate to plan exposures to occur and below which optimization
of protection and safety would continue to be implemented
[SOURCE: IAEA safety glossary 2016 Rev.]
Note 1 to entry: The chosen value for a reference level depends upon the prevailing circumstances of the exposure
[13]
under consideration . Above the reference level, it is judged that the risks from exposure are not justified and
therefore is not allowed to occur. Below the reference level, optimization of personnel protection needs to be
implemented to keep exposures as low as reasonably achievable (ALARA).
3.5
screening level
SL
values that are set up by the laboratory taking into account the characteristics of the measuring
equipment and the test method to guarantee that the test result and its uncer
...
SLOVENSKI STANDARD
oSIST prEN ISO 19581:2019
01-november-2019
Merjenje radioaktivnosti - Radionuklidi, ki sevajo gama žarke - Metoda hitrega
presejanja z uporabo scintilacijskega zaznavala in gama spektrometrije (ISO
19581:2017)
Measurement of radioactivity - Gamma emitting radionuclides - Rapid screening method
using scintillation detector gamma-ray spectrometry (ISO 19581:2017)
Bestimmung der Radioaktivität - Gammastrahlung emittierende Radionuklide -
Schnellverfahren mit Szintillationsdetektor und Gammaspektrometrie (ISO 19581:2017)
Mesurage de la radioactivité - Radionucléides émetteurs gamma - Méthode d'essai de
dépistage par spectrométrie gamma utilisant des détecteurs par scintillation (ISO
19581:2017)
Ta slovenski standard je istoveten z: prEN ISO 19581
ICS:
17.240 Merjenje sevanja Radiation measurements
oSIST prEN ISO 19581:2019 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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oSIST prEN ISO 19581:2019
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oSIST prEN ISO 19581:2019
INTERNATIONAL ISO
STANDARD 19581
First edition
2017-10
Measurement of radioactivity —
Gamma emitting radionuclides
— Rapid screening method using
scintillation detector gamma-ray
spectrometry
Mesurage de la radioactivité — Radionucléides émetteurs gamma —
Méthode d'essai de dépistage par spectrométrie gamma utilisant des
détecteurs par scintillation
Reference number
ISO 19581:2017(E)
©
ISO 2017
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oSIST prEN ISO 19581:2019
ISO 19581:2017(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
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Tel. +41 22 749 01 11
Fax +41 22 749 09 47
copyright@iso.org
www.iso.org
ii © ISO 2017 – All rights reserved
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oSIST prEN ISO 19581:2019
ISO 19581:2017(E)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 2
4 Symbols and units . 3
5 Principle . 4
6 Apparatus . 6
7 Sample container . 7
8 Procedure. 7
8.1 Packaging of samples for measuring purposes . 7
8.2 Calibration . 8
8.2.1 General. 8
8.2.2 Reference source . 8
8.2.3 Check source . 8
8.2.4 Energy calibration . 8
8.2.5 Detection efficiency calibration . 9
8.3 Validation of the screening level .11
8.4 Screening procedure .11
8.4.1 Total spectrum counting / Single channel analyser counting .11
8.4.2 Multichannel analyser counting .12
8.4.3 Effect of sample density .13
9 Test report .13
Annex A (informative) Example of application of ISO 19581 for radio-caesium screening .15
Bibliography .18
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oSIST prEN ISO 19581:2019
ISO 19581:2017(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www.iso.org/patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation on the meaning of ISO specific terms and expressions related to conformity assessment,
as well as information about ISO's adherence to the World Trade Organization (WTO) principles in the
Technical Barriers to Trade (TBT) see the following URL: www.iso.org/iso/foreword.html.
This document was prepared by Technical committee ISO/TC 85, Nuclear Energy, nuclear technologies,
and radiological protection, Subcommittee SC 2, Radiological protection.
iv © ISO 2017 – All rights reserved
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oSIST prEN ISO 19581:2019
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Introduction
Everyone is exposed to natural radiation. The natural sources of radiation are cosmic rays and
naturally occurring radioactive substances which exist in the earth and within the human body. Human
activities involving the use of radiation and radioactive substances add to the radiation exposure
from this natural exposure. Some of those activities, such as the mining and use of ores containing
naturally-occurring radioactive materials (NORM) and the production of energy by burning coal that
contains such substances, simply enhance the exposure from natural radiation sources. Nuclear power
plants and other nuclear installations use radioactive materials and produce radioactive effluent and
waste during operation and on their decommissioning. The use of radioactive materials in industry,
agriculture and research is expanding around the globe.
All these human activities give rise to radiation exposures that are only a small fraction of the global
average level of natural exposure. The medical use of radiation is the largest and a growing man-made
source of radiation exposure in developed countries. It includes diagnostic radiology, radiotherapy,
nuclear medicine and interventional radiology.
Radiation exposure also occurs as a result of occupational activities. It is incurred by workers in
industry, medicine and research using radiation or radioactive substances, as well as by passengers
and crew during air travel and for astronauts. The average level of occupational exposures is generally
[11]
below the global average level of natural radiation exposure .
As uses of radiation increase, so do the potential health risk and the public's concerns. Thus, all these
exposures are regularly assessed in order to
a) improve the understanding of global levels and temporal trends of public and worker exposure
b) to evaluate the components of exposure so as to provide a measure of their relative importance, and
c) to identify emerging issues that may warrant more attention and study.
While doses to workers are mostly directly measured, doses to the public are usually assessed by
indirect methods using radioactivity measurements results performed on various sources: waste,
effluent and/or environmental samples.
To ensure that the data obtained from radioactivity monitoring programs support their intended use, it
is essential that the stakeholders (for example, nuclear site operators, regulatory and local authorities)
agree on appropriate methods and procedures for obtaining representative samples and then
handling, storing, preparing and measuring the test samples. A assessment of the overall measurement
uncertainty needs also to be carried out systematically. As reliable, comparable and ‘fit for purpose’
data are an essential requirement for any public health decision based on radioactivity measurements,
international standards of tested and validated radionuclide test methods are an important tool for
the production of such measurement results. The application of standards serves also to guarantee
comparability over time of the test results and between different testing laboratories. Laboratories
apply them to demonstrate their technical qualifications and to successfully complete proficiency
tests during interlaboratory comparison, two prerequisites for obtaining national accreditation.
Today, over a hundred international standards, prepared by Technical Committees of the International
Standardization Organization, including those produced by ISO/TC85, and the International
Electrotechnical Commission (IEC), are available for application by testing laboratories to measure the
main radionuclides.
Generic standards help testing laboratories to manage the measurement process by setting out the
general requirements and methods to calibrate and validate techniques. These standards underpin
specific standards which describe the test methods to be performed by staff, for example, for different
types of sample. The specific standards cover test methods for:
40 3 14
— Naturally-occurring radionuclides (including K, H, C and those originating from the thorium
226 228 234 238 210
and uranium decay series, in particular Ra, Ra, U, U, Pb) which can be found in
materials from natural sources or can be released from technological processes involving naturally
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oSIST prEN ISO 19581:2019
ISO 19581:2017(E)
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,
3 14 90
and curium), H, C, Sr and gamma emitting radionuclides found in waste, liquid and gaseous
effluent, in environmental matrices (water, air, soil, biota) and food and feed as a result of authorized
releases into the environment and of fallout resulting from the explosion in the atmosphere of
nuclear devices and accidents, such as those that occurred in Chernobyl and Fukushima.
Environmental materials, including foodstuffs, thus may contain radionuclides at activity
concentrations which could present a risk to human health. In order to assess the potential human
exposure to radioactivity and to provide guidance on reducing health risks by taking measures to
decrease radionuclide activity concentrations, the environment and foodstuffs are routinely monitored
for radioactivity content as recommended by the World Health Organization (WHO). Gamma-emitting
radionuclides are usually quantified in environmental and food samples by gamma-ray spectrometry
using High Purity Germanium (HPGe) gamma-ray spectrometry. Following a nuclear accident, a
screening approach based on rapid test methods is recommended to help the decision makers to decide
whether activity concentrations in environmental samples, feed and food samples are above or below
[12]
operational intervention levels (OILs) that are specifically set up to manage nuclear and radiological
emergency. During nuclear emergency response, these default radionuclide specific OILs for food, milk
and water concentrations from laboratory analysis would be used to measure the effectiveness of
[12][13]
protective actions and contribute to determining any further actions required .
In 1989, following the Chernobyl accident, the first version of the Codex Guideline Levels (GLs) for
Radionuclides in Foods Contaminated Following a Nuclear or Radiological Emergency (in the following
referred to as “Codex GLs”) was adopted. The Codex GLs were reviewed in 2006 and are included
[14][15]
in the General Standard for Contaminants and Toxins in Food and Feeds . During a nuclear
106 106 131
emergency situation, the Codex GLs for gamma-emitting radionuclides such as Ru/ Rh and I is
−1 60 103 137 134 144 −1
100 Bq·kg ; the GL for Co, Ru, Cs and Cs, Ce is higher at 1000 Bq·kg but a lower limit of
−1
100 Bq·kg still applies for foods for infants. Default radionuclide specific OILs for food, milk and water
concentrations from laboratory analysis set up by FAO, IAEA, ILO, OECD/NEA, PAHO, OCHA, WHO were
[16]
recently revised .
NOTE The Codex GLs are the activity concentration in foods that would result in an effective dose of
1 mSv/year for members of the Public (infant and adult) in accordance with the most recent recommendations
of the International Commission on Radiological Protection (ICRP) considering that 550 kg of food is consumed
per year by an adult and 200 kg of food and milk is consumed per year by an infant, with 10 % of the diet is of
imported food, all of which is contaminated giving an import to production factor of 0,1. For convenience the
GL values were rounded, and radionuclides with ingestion dose coefficients of similar magnitudes grouped
and given similar GLs values. However, separate GLs were derived for infants and adults due to differences in
radionuclide absorption, metabolism and sensitivity to radiation.
Emergency preparedness should include planning for the implementation of optimized test methods
that can provide rapid estimates of activity concentration to be checked against OILs. Thus, an
international standard on a screening method using Gamma-Ray Spectrometry is justified for use
by testing laboratories carrying out measurements of gamma-emitting radionuclides during an
emergency situation. Such laboratories are intended to obtain a specific accreditation for radionuclide
measurement in environmental and/or food samples.
This document describes, after proper sampling, sample handling and preparation, a screening method
to quantify rapidly the activity concentration of iodine and caesium in environmental, feedstuffs and
foodstuffs samples using scintillation spectrometer during an emergency situation.
This document is one of a set of generic international standards on measurement of radioactivity.
vi © ISO 2017 – All rights reserved
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oSIST prEN ISO 19581:2019
INTERNATIONAL STANDARD ISO 19581:2017(E)
Measurement of radioactivity — Gamma emitting
radionuclides — Rapid screening method using
scintillation detector gamma-ray spectrometry
WARNING — Persons using this document should be familiar with normal testing 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 document be
carried out by suitably trained staff.
1 Scope
This document specifies a screening test method to quantify rapidly the activity concentration of
131 132 134 137
gamma-emitting radionuclides, such as I, Te, Cs and Cs, in solid or liquid test samples using
gamma-ray spectrometry with lower resolution scintillation detectors as compared with the HPGe
detectors (see IEC 61563).
This test method can be used for the measurement of any potentially contaminated environmental
matrices (including soil), food and feed samples as well as industrial materials or products that
have been properly conditioned. Sample preparation techniques used in the screening method
are not specified in this document, since special sample preparation techniques other than simple
machining (cutting, grinding, etc.) should not be required. Although the sampling procedure is of
utmost importance in the case of the measurement of radioactivity in samples, it is out of scope of this
document; other international standards for sampling procedures that can be used in combination with
this document are available (see References [1],[2],[3],[4],[5],[6]).
131 134
The test method applies to the measurement of gamma-emitting radionuclides such as I, Cs
137
and Cs. Using sample sizes of 0,5 l to 1,0 l in a Marinelli beaker and a counting time of 5 min to
−1
20 min, decision threshold of 10 Bq·kg can be achievable using a commercially available scintillation
spectrometer [e.g. thallium activated sodium iodine (NaI(Tl)) spectrometer 2” ϕ × 2” detector size, 7 %
resolution (FWHM) at 662 keV, 30 mm lead shield thickness].
This test method also can be performed in a “makeshift” laboratory or even outside a testing laboratory
on samples directly measured in the field where they were collected.
During a nuclear or radiological emergency, this test method enables a rapid measurement of the sample
activity concentration of potentially contaminated samples to check against operational intervention
levels (OILs) set up by decision makers that would trigger a predetermined emergency response to
[12]
reduce existing radiation risks .
Due to the uncertainty associated with the results obtained with this test method, test samples requiring
more accurate test results can be measured using high-purity germanium (HPGe) detectors gamma-ray
[7][8]
spectrometry in a testing laboratory, following appropriate preparation of the test samples .
This document does not contain criteria to establish the activity concentration of OILs.
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 2017 – All rights reserved 1
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ISO 19581:2017(E)
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
ISO/IEC 17025, General requirements for the competence of testing and calibration laboratories
IEC 61453, Nuclear instrumentation — Scintillation gamma ray detector systems for the assay of
radionuclides – Calibration and routine tests
3 Terms and definitions
For the purposes of this document, the terms, definitions, and the symbols and abbreviations given in
ISO 80000-10 and the following apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at http://www.iso.org/obp
— IEC Electropedia: available at http://www.electropedia.org/
3.1
blank sample
sample, liquid or solid, with very low to no activity for radiation of the same type and region of interest,
with a mass and a composition as close as possible to those of the test sample
3.2
emergency
non-routine situation that necessitates prompt action, primarily to mitigate a hazard or adverse
consequences for human life and health, property and the environment
[SOURCE: IAEA safety glossary 2016 Rev.]
Note 1 to entry: This includes nuclear and radiological emergencies and conventional emergencies such as
fires, release of hazardous chemicals, storms or earthquakes. It includes situations for which prompt action is
[12]
warranted to mitigate the effects of a perceived hazard .
3.3
operational intervention level
OIL
set level of a measurable quantity that corresponds to a generic criterion
[SOURCE: IAEA safety glossary 2016 Rev. Mod]
Note 1 to entry: OILs are calculated levels, measured by instruments or determined by laboratory analysis,
that corresponds to an intervention level or action level. These are typically expressed in terms of dose rates
or of activity of radioactive material released, time integrated air activity concentrations, ground or surface
concentrations, or activity concentrations of radionuclides in environmental, food or water samples. OILs are
used immediately and directly (without further assessment) to determine the appropriate protective actions on
[12]
the basis of an environmental measurement .
2 © ISO 2017 – All rights reserved
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oSIST prEN ISO 19581:2019
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3.4
reference level
level of dose, risk or activity
concentration above which it is not appropriate to plan exposures to occur and below which optimization
of protection and safety would continue to be implemented
[SOURCE: IAEA safety glossary 2016 Rev.]
Note 1 to entry: The chosen value for a reference level depends upon the prevailing circumstances of the exposure
[13]
under consideration . Above the reference level, it is judged that the risks from exposure are not justified and
therefore is not allowed to occur. Below the reference level, optimization of personnel protection needs to be
implemented to keep exposures as low as reasonably achievable (ALARA).
3.5
screening level
SL
values that are set up by the laboratory taking into account the characteristics of the measuring
equipment and the test method to guarantee that the test result and its uncertainty obtained are fit for
purpose for comparison with the operational intervention levels (OILs)
Note 1 to entry: The screening level is less than the OIL. Therefore food is safe for consumption if the screening
[16]
level is not exceeded. Actions to take, if the food is not safe for consumption, are given in Reference .
4 Symbols and units
A Activity of each radionuclide in reference source, at the measurement time, in becquerels
c Activity concentration of each radionuclide expressed in becquerels per kilogram
A
c Activity concentration that corresponds to the screening level of each radionuclide
A,SL
expressed in becquerels per kilogram
c Activity concentration that corresponds to the OIL of each radionuclide expressed in
A,RL
becquerels per kilogram
Decision threshold, without and with corrections, in becquerels per kilogram
*
c
A
# Detection limit, without and with corrections, in becquerels per kilogram
c
A
Upper limits of the confidence interval, in becquerels per kilogram
c
A
R the ratio of the indicated value of a spectrometer to the conventional true value of spe-
i
cific radionuclide, i
ε Counting efficiency of the detector at energy, E
E
ε Radionuclide-specific counting efficiency of the detector at energy, E, of specific radi-
i,E
onuclide, i
n , Number of net counts in the gamma-ray energy region of interest, at energy E, in the
N,E
sample spectrum, in the calibration spectrum and in the spectrum obtained from the
n
Ns,E,
measurement of reference sample having activity that corresponds to the screening
n
level, respectively
N,SL,E
n , n , Number of gross counts in the gamma-ray energy region of interest, at energy E, in the
g,E gb,E
sample spectrum, in the background spectrum, in the calibration spectrum and in the
n n
gs,E g,SL,E
spectrum obtained from the measurement of reference sample having activity that
corresponds to the screening level, respectively
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P Probability of the emission of a gamma ray with energy, E, of each radionuclide, per decay
E
R Response of the detector/radiometer to the reference activity of radionuclide, i
i
t Sample counting live time, in seconds
g
T Background counting live time, in seconds
b
t Reference source counting live time, in seconds
s
t Counting live time, in seconds, of a reference sample with an activity corresponding to
SL
a screening level
t The two sided t-distribution with k-1 degree of freedom and α two sides probability
k-1,α
u(c ) Standard uncertainty associated with the measurement result c , without and with
A A
corrections, in becquerels per kilogram
U Expanded uncertainty calculated by U = k ·u (c ) with k = 1, 2., in becquerels per kilogram
A
m Mass of the sample for test, in kilograms
α, β Probability of a false positive and false negative decision, respectively
1−γ Probability for the coverage interval of the measurand
5 Principle
During a nuclear or radiological emergency, it is essential to measure rapidly the activity concentration
in samples from the environment and potentially contaminated foodstuffs and feed to protect
workers and the public, in accordance with international standards, by keeping doses below the dose
[13]
reference levels . It is recognized among organizations responsible for emergency management
that good preparedness can substantially improve the emergency situation response. Thus default
OILs for food are set up by national authorities, and measurement procedures using commonly
available contamination screening equipment are implemented to meet the OILs criteria. This should
be carried out as part of the emergency preparedness process. The process of assessing radionuclide
concentrations in food, milk and water is shown in Figure 1. During the process of assessing radionuclide
concentrations in food, milk and water the potentially contaminated food should be screened over a
wide area and analysed to determine promptly the activity concentration of gross and/or individual
radionuclides. If the OIL are not exc
...
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