SIST EN ISO 19581:2025
(Main)Measurement of radioactivity - Gamma emitting radionuclides - Rapid screening method using scintillation detector gamma-ray spectrometry (ISO 19581:2025)
Measurement of radioactivity - Gamma emitting radionuclides - Rapid screening method using scintillation detector gamma-ray spectrometry (ISO 19581:2025)
This document 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[7]).
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[8]. 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 [9] [10] [11] [12] [13] [14]).
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 iodide (NaI(Tl)) spectrometer 2” ϕ × 2” (50,8 mm Ø x 50,8 mm) 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 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[2].
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[15][16].
This document does not contain criteria to establish the activity concentration of OILs.
Mesurage de la radioactivité - Radionucléides émetteurs gamma - Méthode d'essai de dépistage par spectrométrie gamma utilisant des détecteurs par scintillation (ISO 19581:2025)
Le présent document spécifie une méthode d’essai de dépistage pour quantifier rapidement la concentration d’activité 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[7]).
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.[8] Les techniques de préparation des échantillons utilisées dans la méthode de dépistage 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 [9] [10] [11] [12] [13] [14]).
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” (50,8 mm Ø × 50,8 mm), 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 «de fortune» 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 la concentration d’activité 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[2].
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[15][16].
Le présent document ne comprend aucun critère permettant d’établir la concentration d’activité des NOI.
Merjenje radioaktivnosti - Radionuklidi, ki sevajo gama žarke - Metoda hitrega presejanja z uporabo scintilacijskega zaznavala in gama spektrometrije (ISO 19581:2025)
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
01-december-2025
Merjenje radioaktivnosti - Radionuklidi, ki sevajo gama žarke - Metoda hitrega
presejanja z uporabo scintilacijskega zaznavala in gama spektrometrije (ISO
19581:2025)
Measurement of radioactivity - Gamma emitting radionuclides - Rapid screening method
using scintillation detector gamma-ray spectrometry (ISO 19581:2025)
Mesurage de la radioactivité - Radionucléides émetteurs gamma - Méthode d'essai de
dépistage par spectrométrie gamma utilisant des détecteurs par scintillation (ISO
19581:2025)
Ta slovenski standard je istoveten z: EN ISO 19581:2025
ICS:
17.240 Merjenje sevanja Radiation measurements
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
EN ISO 19581
EUROPEAN STANDARD
NORME EUROPÉENNE
October 2025
EUROPÄISCHE NORM
ICS 17.240 Supersedes EN ISO 19581:2020
English Version
Measurement of radioactivity - Gamma emitting
radionuclides - Rapid screening method using scintillation
detector gamma-ray spectrometry (ISO 19581:2025)
Mesurage de la radioactivité - Radionucléides
émetteurs gamma - Méthode d'essai de dépistage par
spectrométrie gamma utilisant des détecteurs par
scintillation (ISO 19581:2025)
This European Standard was approved by CEN on 28 September 2025.
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, Türkiye 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
© 2025 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 19581:2025 E
worldwide for CEN national Members.
Contents Page
European foreword . 3
European foreword
This document (EN ISO 19581:2025) has been prepared by Technical Committee ISO/TC 85 "Nuclear
energy, nuclear technologies, and radiological protection " in collaboration with 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 April 2026, and conflicting national standards shall be
withdrawn at the latest by April 2026.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
This document supersedes EN ISO 19581:2020.
Any feedback and questions on this document should be directed to the users’ national standards
body/national committee. A complete listing of these bodies can be found on the CEN website.
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, Türkiye and the
United Kingdom.
Endorsement notice
The text of ISO 19581:2025 has been approved by CEN as EN ISO 19581:2025 without any modification.
International
Standard
ISO 19581
Second edition
Measurement of radioactivity —
2025-09
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 19581:2025(en) © ISO 2025
ISO 19581:2025(en)
© ISO 2025
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: +41 22 749 01 11
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii
ISO 19581:2025(en)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms, definitions . 2
4 Symbols . 3
5 Principle . 4
6 Apparatus . 6
7 Sample container . 7
8 Procedure . 8
8.1 Packaging of samples for measuring purposes .8
8.2 Calibration .8
8.2.1 General .8
8.2.2 Reference source .9
8.2.3 Check source .9
8.2.4 Energy calibration.9
8.2.5 Detection efficiency calibration .10
8.3 Validation of the screening level . 12
8.4 Screening procedure . 12
8.4.1 Total spectrum counting/Single channel analyser counting. 12
8.4.2 Multichannel analyser counting . 13
8.4.3 Effect of sample density . 13
9 Test report . 14
Annex A (informative) Example of application of this document for radio-caesium screening .16
Bibliography .21
iii
ISO 19581:2025(en)
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).
ISO draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). ISO takes no position concerning the evidence, validity or applicability of any claimed patent
rights in respect thereof. As of the date of publication of this document, ISO had not received notice of (a)
patent(s) which may be required to implement this document. However, implementers are cautioned that
this may not represent the latest information, which may be obtained from the patent database available at
www.iso.org/patents. ISO shall not be held responsible for identifying any or all such patent rights.
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and expressions
related to conformity assessment, as well as information about ISO's adherence to the World Trade
Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 85, Nuclear energy, nuclear technologies, and
radiological protection, Subcommittee SC 2, Radiological protection, in collaboration with the European
Committee for Standardization (CEN) Technical Committee CEN/TC 430, Nuclear energy, nuclear technologies,
and radiological protection, in accordance with the Agreement on technical cooperation between ISO and
CEN (Vienna Agreement).
This second edition cancels and replaces the first edition (ISO 19581:2017), which has been technically
revised.
The main changes are as follows:
— the updated IAEA Nuclear Safety and Security Glossary was referenced;
— Annex A has been updated with considering recent technological improvements;
— editorial changes have been made.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.
iv
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.