SIST EN ISO 16424:2018

Nuclear energy - Evaluation of homogeneity of Gd distribution within gadolinium fuel blends and determination of Gd2O3 content in gadolinium fuel pellets by measurements of uranium and gadolinium elements (ISO 16424:2012)

ISO 16424:2012 is applicable to the evaluation of the homogeneity of Gd distribution within gadolinium fuel blends, and the determination of the Gd2O3 content in sintered fuel pellets of Gd2O3+UO2 from 1 % to 10 %, by measurements of gadolinium (Gd) and uranium (U) elements using ICP-AES.
After performing measurements of Gd and U elements using ICP-AES, if statistical methodology is additionally applied, homogeneity of Gd distribution within a Gd fuel pellet lot can also be evaluated. However, ISO 16424:2012 covers the statistical methodology only on a limited basis.

Kernenergie - Bewertung der Homogenität der Gd-Verteilung in Gadolinium-Brennstoffgemischen und Bestimmung des Gd₂O₃-Gehaltes in Gadolinium-Brennstofftabletten durch Messung der Uran- und Gadolinium-Bestandteile (ISO 16424:2012)

Diese Internationale Norm ist für die Beurteilung der Homogenität der Gd Verteilung in Gadolinium-Brennstoffgemischen und die Bestimmung des Gehalts von Gd2O3 in gesinterten Brennstofftabletten von Gd2O3 + UO2 von 1 % bis 10 % durch Messung von Gadolinium-(Gd ) und Uran-(U )Elementen mit ICP-AES anwendbar.
Nach der Durchführung von Messungen von Gd  und U Elementen mit ICP-AES kann bei zusätzlicher Anwendung von statistischen Verfahren ebenfalls die Homogenität der Gd Verteilung in einem Gd Brennstofftabletten Los beurteilt werden. Diese Internationale Norm behandelt jedoch die statistischen Verfahren nur eingeschränkt.
ANMERKUNG 1   ISO 16796 bietet ebenfalls ein Verfahren für die Bestimmung des Gehalts von Gd2O3 durch atomare Emissionsspektrometrie mit einer induktiv gekoppelten Plasmaquelle (en: Inductively Coupled Plasma Atomic Emission Spectrometry, ICP-AES). Das Verfahren von ISO 16796 unterscheidet sich von dem in dieser Internationalen Norm.
ANMERKUNG 2   In dieser Internationalen Norm stellt das Gadolinium-Brennstoffgemisch ein Gemisch aus Urandioxid-(UO2 )Pulver und Gadoliniumoxid-(Gd2O3 )Pulver dar. Das physikalisch gemischte und homogenisierte Pulver kann zusätzlich relativ große Mengen an Uranoxid-(U3O8-)Pulverpartikeln und/oder die durch die Oxidation von Gd-Tabletten erhaltenen M3O8 Pulverpartikel enthalten. In dieser Internationalen Norm stellt das Symbol „M“ in der chemischen Formel „M3O8“ und in der Benennung „O/M Verhältnis“ die Metallelemente U und Gd dar.

Énergie nucléaire - Évaluation de l'homogénéité de la distribution du Gd dans les mélanges de combustibles au gadolinium et détermination de la teneur en Gd2O3 dans les pastilles combustibles au gadolinium par mesurage des éléments uranium et gadolinium (ISO 16424:2012)

L'ISO 16424:2012 spécifie une méthode d'évaluation de l'homogénéité de la distribution du Gd dans les mélanges de combustibles au gadolinium et de détermination de la teneur en Gd2O3 dans les pastilles combustibles frittées de Gd2O3+UO2 allant de 1 % à 10 %, par mesurage des éléments gadolinium (Gd) et uranium (U) en utilisant la méthode de spectrométrie par émission atomique à plasma à couplage inductif (ICP-AES).
Après mesurage des éléments Gd et U en utilisant la méthode ICP-AES, si la méthodologie statistique est en outre appliquée, l'homogénéité de la distribution du Gd dans un lot de pastilles combustibles au Gd peut également être évaluée. Cependant, l'ISO 16424:2012 ne couvre la méthodologie statistique que sur une base restreinte.

Jedrska energija - Vrednotenje homogenosti porazdelitve gadolinija (Gd) v gadolinijevih gorivnih mešanicah in ugotavljanje vsebnosti Gd203 v gadolinijevih gorivnih peletih z merjenjem elementov urana in gadolinija (ISO 16424:2012)

Standard ISO 16424:2012 se uporablja za vrednotenje homogenosti porazdelitve gadolinija (Gd) v gadolinijevih gorivnih mešanicah in ugotavljanje vsebnosti Gd203 v sintranih gadolinijevih gorivnih peletih Gd2O3+UO2 od 1 % do 10 % na podlagi merjenja elementov gadolinija (Gd) in urana (U) z uporabo atomske emisijske spektroskopije z induktivno sklopljeno plazmo (ICP-AES).
Če je po meritvah elementov Gd in U z uporabo ICP-AES dodatno uporabljena statistična metodologija, je mogoče ovrednotiti tudi homogenost porazdelitve gadolinija (Gd) v gadolinijevih gorivnih peletih. Vendar pa standard ISO 16424:2012 zajema statistično metodologijo le v omejenem obsegu.

General Information

• Status: Published
• Public Enquiry End Date: 14-Jun-2017
• Publication Date: 17-Dec-2017
• ICS: 27.120.30 - Fissile materials and nuclear fuel technology
• Technical Committee: I13 - Imaginarni 13
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 26-Oct-2017
• Due Date: 31-Dec-2017
• Completion Date: 18-Dec-2017
• Ref Project: EN ISO 16424:2017 - Nuclear energy - Evaluation of homogeneity of Gd distribution within gadolinium fuel blends and determination of Gd2O3 content in gadolinium fuel pellets by measurements of uranium and gadolinium elements (ISO 16424:2012)

Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN ISO 16424:2018
01-februar-2018
Jedrska energija - Vrednotenje homogenosti porazdelitve gadolinija (Gd) v
gadolinijevih gorivnih mešanicah in ugotavljanje vsebnosti Gd203 v gadolinijevih
gorivnih peletih z merjenjem elementov urana in gadolinija (ISO 16424:2012)
Nuclear energy - Evaluation of homogeneity of Gd distribution within gadolinium fuel
blends and determination of Gd2O3 content in gadolinium fuel pellets by measurements
of uranium and gadolinium elements (ISO 16424:2012)
.HUQHQHUJLH%HZHUWXQJGHU+RPRJHQLWlWGHU*G9HUWHLOXQJLQ*DGROLQLXP
%UHQQVWRIIJHPLVFKHQXQG%HVWLPPXQJGHV*G"2"*HKDOWHVLQ*DGROLQLXP
%UHQQVWRIIWDEOHWWHQGXUFK0HVVXQJGHU8UDQXQG*DGROLQLXP%HVWDQGWHLOH,62

Énergie nucléaire - Évaluation de l'homogénéité de la distribution du Gd dans les
mélanges de combustibles au gadolinium et détermination de la teneur en Gd2O3 dans
les pastilles combustibles au gadolinium par mesurage des éléments uranium et
gadolinium (ISO 16424:2012)
Ta slovenski standard je istoveten z: EN ISO 16424:2017
ICS:
27.120.30 Cepljivi materiali in jedrska Fissile materials and nuclear
gorivna tehnologija fuel technology
SIST EN ISO 16424:2018 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN ISO 16424:2018

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SIST EN ISO 16424:2018


EN ISO 16424
EUROPEAN STANDARD

NORME EUROPÉENNE

October 2017
EUROPÄISCHE NORM
ICS 27.120.30
English Version

Nuclear energy - Evaluation of homogeneity of Gd
distribution within gadolinium fuel blends and
determination of Gd2O3 content in gadolinium fuel pellets
by measurements of uranium and gadolinium elements
(ISO 16424:2012)
Énergie nucléaire - Évaluation de l'homogénéité de la Kernenergie - Bewertung der Homogenität der Gd-
distribution du Gd dans les mélanges de combustibles Verteilung in Gadolinium-Brennstoffgemischen und
au gadolinium et détermination de la teneur en Gd2O3 Bestimmung des Gd2O3-Gehaltes in Gadolinium-
dans les pastilles combustibles au gadolinium par Brennstofftabletten durch Messung der Uran- und
mesurage des éléments uranium et gadolinium (ISO Gadolinium-Bestandteile (ISO 16424:2012)
16424:2012)
This European Standard was approved by CEN on 13 September 2017.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this
European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references
concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN
member.

This European Standard exists in three official versions (English, French, German). A version in any other language made by
translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management
Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,
Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey and United Kingdom.





EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2017 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 16424:2017 E
worldwide for CEN national Members.

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SIST EN ISO 16424:2018
EN ISO 16424:2017 (E)
Contents Page
European foreword . 3

2

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SIST EN ISO 16424:2018
EN ISO 16424:2017 (E)
European foreword
The text of ISO 16424:2012 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 16424:2017 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 April 2018, and conflicting national standards shall be
withdrawn at the latest by April 2018.
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, Former Yugoslav Republic of Macedonia,
France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta,
Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey and the United Kingdom.
Endorsement notice
The text of ISO 16424:2012 has been approved by CEN as EN ISO 16424:2017 without any modification.

3

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SIST EN ISO 16424:2018

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SIST EN ISO 16424:2018
INTERNATIONAL ISO
STANDARD 16424
First edition
2012-12-01
Nuclear energy — Evaluation of
homogeneity of Gd distribution
within gadolinium fuel blends and
determination of Gd O content
2 3
in gadolinium fuel pellets by
measurements of uranium and
gadolinium elements
Énergie nucléaire — Évaluation de l’homogénéité de la distribution
du Gd dans les mélanges de combustibles au gadolinium et
détermination de la teneur en Gd O dans les pastilles combustibles
2 3
au gadolinium par mesurage des éléments uranium et gadolinium
Reference number
ISO 16424:2012(E)
©
ISO 2012

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SIST EN ISO 16424:2018
ISO 16424:2012(E)

COPYRIGHT PROTECTED DOCUMENT
© ISO 2012
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any
means, electronic or mechanical, including photocopying and microfilm, without permission in writing from either ISO at the
address below or ISO’s member body in the country of the requester.
ISO copyright office
Case postale 56 • CH-1211 Geneva 20
Tel. + 41 22 749 01 11
Fax + 41 22 749 09 47
E-mail [e-mail]
Web www.iso.org
Published in Switzerland
ii © ISO 2012 – All rights reserved

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SIST EN ISO 16424:2018
ISO 16424:2012(E)

Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Principle . 1
4 Apparatus . 2
4.1 High dispersion direct reading ICP-AES . 2
4.2 Analytical balance. 2
4.3 Small stainless steel spoon . 2
5 Reagents . 2
6 Reference solutions . 2
6.1 Gadolinium element reference solutions . 2
6.2 Uranium element reference solutions . 3
7 Sample preparation . 3
7.1 Sample preparation for evaluation of Gd homogeneity in gadolinium fuel blend . 3
7.2 Sample preparation for determining the Gd O content of Gd fuel pellets . 3
2 3
8 Calibration and analysis of the samples . 3
8.1 Calibration of Gd peak line intensity . 3
8.2 Calibration of U peak line intensity . 3
8.3 Evaluation of Gd homogeneity in gadolinium fuel blend . 3
8.4 Determination of Gd O content in gadolinium fuel pellet . 4
2 3
9 Precision . 6
10 Test report . 6
Annex A (informative) Calibration and Gd and U measurement uncertainties .7
Annex B (informative) Derivation of O/M and O/U ratio formulas .10
Annex C (informative) Evaluation of Gd O measurement precision .12
2 3
Bibliography .15
© ISO 2012 – All rights reserved iii

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SIST EN ISO 16424:2018
ISO 16424:2012(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.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International
Standards adopted by the technical committees are circulated to the member bodies for voting.
Publication as an International Standard requires approval by at least 75 % of the member bodies
casting a vote.
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.
ISO 16424 was prepared by Technical Committee ISO/TC 85, Nuclear Energy, Nuclear Technologies, and
Radiological Protection, Subcommittee SC 5, Nuclear Fuel Cycle.
iv © ISO 2012 – All rights reserved

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SIST EN ISO 16424:2018
INTERNATIONAL STANDARD ISO 16424:2012(E)
Nuclear energy — Evaluation of homogeneity of
Gd distribution within gadolinium fuel blends and
determination of Gd O content in gadolinium fuel pellets
2 3
by measurements of uranium and gadolinium elements
1 Scope
This International Standard is applicable to the evaluation of the homogeneity of Gd distribution within
gadolinium fuel blends, and the determination of the Gd O content in sintered fuel pellets of Gd O +UO
2 3 2 3 2
from 1 % to 10 %, by measurements of gadolinium (Gd) and uranium (U) elements using ICP-AES.
After performing measurements of Gd and U elements using ICP-AES, if statistical methodology is
additionally applied, homogeneity of Gd distribution within a Gd fuel pellet lot can also be evaluated.
However, this International Standard covers the statistical methodology only on a limited basis.
NOTE 1 ISO 16796 also provides a method for Gd O content determination by atomic emission spectrometry
2 3
using an inductively coupled plasma source (ICP-AES). The methodology of ISO 16796 is different from the one of
this International Standard.
NOTE 2 In this International Standard, gadolinium fuel blend represents a mixture of uranium dioxide (UO )
2
powder and gadolinium oxide (Gd O ) powder. The physically blended and homogenized powder may additionally
2 3
contain in it rather large quantities of uranium oxide (U O ) powder particles and/or the M O powder particles
3 8 3 8
obtained by oxidation of Gd pellets. In this International Standard, the symbol “M” in the chemical formula “M O ”
3 8
and in the terminology “O/M ratio” represents metallic elements U and Gd.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and are
indispensible for its application. For dated references, only the edition cited applies. For undated
references, the latest edition of the referenced document (including amendments) applies.
ISO 3696:1987, Water for analytical laboratory use — Specification and test methods
3 Principle
If the Gd and U element contents and the oxygen to metal atomic ratio (commonly referred to as O/M
ratio) in a gadolinium fuel pellet are measured or determined, the Gd O content of that pellet can be
2 3
determined by calculation based on the stoichiometry of the pellet. The stoichiometric compositions
for Gd and U will depend upon pellet manufacturing specification. If the specification requires that the
Gd O content in the pellet be 6 % as mass fraction, after manufacturing, the ratio of total Gd mass to
2 3
total U mass in that pellet will be close to 0,063.
The Gd and U element content values measured from a powder blend can make it possible to evaluate
whether Gd distribution in the powder is sufficiently homogeneous. Moreover, the two values make it
possible to estimate accurately the actual Gd O content of the pellet after sintering. The estimated
2 3
Gd O content can be used to anticipate whether the Gd pellets to be produced will meet Gd O content
2 3 2 3
specifications or not.
© ISO 2012 – All rights reserved 1

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SIST EN ISO 16424:2018
ISO 16424:2012(E)

Impurity interferences have not been observed for the usual samples of the nuclear grade material.
Very small quantities of impurity elements which might be contained in the samples do not affect the
principle of this International Standard.
NOTE Even in the case of M O powder or mixture of UO powder and Gd O powder, if the Gd and U element
3 8 2 2 3
contents and the O/M ratio are measured or determined, the Gd O content (or Gd content) of that powder can be
2 3
determined by calculation based on the stoichiometry of the powder. Using the Gd O content (or Gd content) thus
2 3
obtained and the O/M ratio, the uranium concentration factor of the powder can also be calculated so as to obtain
accurate uranium accounting data.
4 Apparatus
4.1 High dispersion direct reading ICP-AES
The measured values should be indicated down to at least two decimal places when element
concentrations in the range from 1 mg/l to 100 mg/l are measured. For determination of Gd and U
element concentrations, 354,580 nm and 398,579 nm peaks in atomic emission spectrum are used,
respectively. However, instead of the two peaks, other peaks are also available.
4.2 Analytical balance
The sensitivity of the balance is ± 0,1 mg.
4.3 Small stainless steel spoon
The small spoon is able to accommodate powder in the range from 1 mg to 100 mg.
4.4 Hot plate.
4.5 Glass beakers or polytetrafluoroethylene (PTFE) beakers.
4.6 Micropipettes.
4.7 Volumetric flasks.
4.8 Percussion mortar.
5 Reagents
5.1 Nitric acid, aqueous solution at a volume fraction of 50 %.
5.2 Water, distilled water or water complying with grade 3 of ISO 3696:1987.
6 Reference solutions
6.1 Gadolinium element reference solutions
Three Gd reference solutions whose Gd concentrations are 5 mg/l, 10 mg/l and 15 mg/l, respectively,
1)
are used for calibration. These Gd reference solutions are the ones that have been manufactured by
diluting a reference material with the water specified in 5.2.
1) A certified gadolinium reference material from NIST (National Institute of Standards and Technology, USA) is an
example of a suitable product available commercially. This information is given for the convenience of users of this
document and does not constitute an endorsement of this product by ISO.
2 © ISO 2012 – All rights reserved

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SIST EN ISO 16424:2018
ISO 16424:2012(E)

6.2 Uranium element reference solutions
Three U reference solutions whose U concentrations are 50 mg/l, 70 mg/l and 100 mg/l, respectively,
2)
are used for calibration. These U reference solutions are the ones that have been manufactured by
diluting a reference material with the water specified in 5.2.
7 Sample preparation
7.1 Sample preparation for evaluation of Gd homogeneity in gadolinium fuel blend
Using a small spoon, take randomly at least five different powder samples from the blended powder, then
dissolve each of the samples in the nitric acid solution of 5.1. Number each beaker individually. The U
concentrations of the sample solutions prepared should be somewhere in the range from 50 mg/l to 100 mg/l.
To evaluate the homogeneity of the Gd distribution within a Gd fuel pellet lot, take at least five different
pellet samples from the lot and then crush each of the pellets into small pellet fragments as described in 7.2.
NOTE 1 If about 2 mg of the powder sample is dissolved in 20 ml of the nitric acid solution, the required uranium
concentration range will be obtained. Alternatively, if about 100 mg of sample is dissolved and then diluted by
proper pipetting and addition of distilled water, the concentration range can also be obtained.
7.2 Sample preparation for determining the Gd O content of Gd fuel pellets
2 3
After crushing a gadolinium fuel pellet using a percussion mortar, randomly take a small sample from
the pellet fragments, and dissolve it in the nitric acid solution. The U concentration should be somewhere
in the range from 50 mg/l to 100 mg/l.
8 Calibration and analysis of the samples
8.1 Calibration of Gd peak line intensity
The three Gd reference solutions of 6.1 are used to calibrate the intensity of the Gd peak line. The Gd peak
line intensity is repeatedly measured to establish an intensity-versus-concentration curve (regression
curve) needed for determination of Gd concentrations. See A.1.
8.2 Calibration of U peak line intensity
The three U reference solutions of 6.2 are used to calibrate the intensity of the U peak line. The U peak
line intensity is repeatedly measured to establish an intensity-versus-concentration curve (regression
curve) needed for determination of U concentrations. See A.2.
8.3 Evaluation of G
...