EN ISO 12800:2019

SLOVENSKI STANDARD
01-september-2019
Tehnologija jedrskih goriv - Smernice za merjenje specifične površine prahu
uranovega oksida po metodi BET (ISO 12800:2017)
Nuclear fuel technology - Guidelines on the measurement of the specific surface area of
uranium oxide powders by the BET method (ISO 12800:2017)
Kernbrennstofftechnologie - Leitlinien für die Messung des spezifischen
Oberflächenbereiches von Uranoxid-Pulvern mittels der BET-Methode (ISO 12800:2017)
Technologie du combustible nucléaire - Lignes directrices pour le mesurage de l'aire
massique (surface spécifique) des poudres d'oxyde d'uranium par la méthode BET (ISO
12800:2017)
Ta slovenski standard je istoveten z: EN ISO 12800:2019
ICS:
27.120.30 Cepljivi materiali in jedrska Fissile materials and nuclear
gorivna tehnologija fuel technology
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN ISO 12800
EUROPEAN STANDARD
NORME EUROPÉENNE
June 2019
EUROPÄISCHE NORM
ICS 27.120.30
English Version
Nuclear fuel technology - Guidelines on the measurement
of the specific surface area of uranium oxide powders by
the BET method (ISO 12800:2017)
Technologie du combustible nucléaire - Lignes Kernbrennstofftechnologie - Leitlinien für die Messung
directrices pour le mesurage de l'aire massique des spezifischen Oberflächenbereiches von Uranoxid-
(surface spécifique) des poudres d'oxyde d'uranium Pulvern mittels der BET-Methode (ISO 12800:2017)
par la méthode BET (ISO 12800:2017)
This European Standard was approved by CEN on 8 March 2019.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this
European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references
concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN
member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by
translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management
Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, 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: Rue de la Science 23, B-1040 Brussels
© 2019 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 12800:2019 E
worldwide for CEN national Members.

Contents Page
European foreword . 3

European foreword
The text of ISO 12800:2017 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 12800:2019 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 December 2019, and conflicting national standards
shall be withdrawn at the latest by December 2019.
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 12800:2017 has been approved by CEN as EN ISO 12800:2019 without any modification.

INTERNATIONAL ISO
STANDARD 12800
Second edition
2017-06
Nuclear fuel technology — Guidelines
on the measurement of the specific
surface area of uranium oxide
powders by the BET method
Technologie du combustible nucléaire — Lignes directrices pour le
mesurage de l’aire massique (surface spécifique) des poudres d’oxyde
d’uranium par la méthode BET
Reference number
ISO 12800:2017(E)
©
ISO 2017
ISO 12800:2017(E)
© 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
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ii © ISO 2017 – All rights reserved

ISO 12800:2017(E)
Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Principle . 1
4.1 Summary of the BET method . 1
4.2 Isothermal adsorption curves . 1
4.3 Conditions and assumptions . 2
5 Procedure. 3
5.1 Sample preparation . 3
5.2 Volumetric measurement . 3
5.3 Gravimetric measurement . 3
5.4 Original and single-point methods . 3
5.5 Dynamic method (carrier gas method) . 4
5.6 Alternative methods . 4
6 Expression of results . 4
6.1 Methods of calculation . 4
6.1.1 Multipoint determination . 4
6.1.2 Single-point determination . 7
6.2 Precision and accuracy. 7
7 Test report . 7
Bibliography . 8
ISO 12800:2017(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
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different types of ISO documents should be noted. This document was drafted in accordance with the
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This document was prepared by Technical Committee ISO/TC 85, Nuclear energy, nuclear technologies,
and radiological protection, Subcommittee SC 5, Nuclear installations, processes and technologies.
This second edition cancels and replaces the first edition (ISO 12800:2003), which has been technically
revised.
iv © ISO 2017 – All rights reserved

INTERNATIONAL STANDARD ISO 12800:2017(E)
Nuclear fuel technology — Guidelines on the measurement
of the specific surface area of uranium oxide powders by
the BET method
1 Scope
This document gives guidelines on the determination of the specific surface area of as-fabricated
uranium dioxide powder by volumetric or gravimetric determination of the amount of nitrogen
adsorbed on the powder, and can be applied to other similar materials, e.g. U O , UO -PuO powders,
3 8 2 2
and other bodies with similar surface areas, e.g. powder granules or green pellets, provided that the
conditions described are fulfilled. Modifications using other adsorbing gases are included.
2 2
The method is relevant as long as the expected value is in the range between 1 m /g and 10 m /g.
2 Normative references
There are no normative references in this document.
3 Terms and definitions
No terms and definitions are listed in this document.
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/
4 Principle
4.1 Summary of the BET method
The BET method is based on the determination of the amount of gas necessary to cover the surface by a
monomolecular layer. This amount is determined from the isothermal adsorption curve of nitrogen (N )
at the temperature of liquid nitrogen (77,4 K) according to
...