SIST EN ISO 12800:2019

Nuclear fuel technology - Guidelines on the measurement of the specific surface area of uranium oxide powders by the BET method (ISO 12800:2017)

ISO 12800:2017 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. U3O8, UO2-PuO2 powders, 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.
The method is relevant as long as the expected value is in the range between 1 m2/g and 10 m2/g.

Kernbrennstofftechnologie - Leitlinien für die Messung des spezifischen Oberflächenbereiches von Uranoxid-Pulvern mittels der BET-Methode (ISO 12800:2017)

Dieses Dokument gibt Leitlinien für die Bestimmung der spezifischen Oberfläche von Urandioxid im Her-stellungszustand durch volumetrische oder gravimetrische Bestimmung der auf dem Pulver adsorbierten Stickstoffmenge, und es kann auf ähnliche Materialien wie z. B. U3O8 , UO2 PuO2 Pulver und andere Körper mit ähnlichen Oberflächen, z. B. Pulvergranulate oder Rohpellets, angewandt werden, vorausgesetzt, dass die beschriebenen Bedingungen erfüllt sind. Änderungen unter Verwendung anderer adsorbierender Gase sind enthalten.
Das Verfahren ist relevant, solange der Erwartungswert im Bereich zwischen 1 m2/g und 10 m2/g liegt.

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)

L'ISO 12800:2017 est applicable à la détermination de l'aire massique de poudres brutes d'oxyde d'uranium par une mesure volumétrique ou gravimétrique de la quantité d'azote adsorbée sur la poudre. La méthode est applicable à d'autres matières comparables, par exemple aux poudres de U3O8 et aux mélanges UO2-PuO2, ainsi qu'à d'autres corps ayant des aires similaires, par exemple des granules de poudre ou des pastilles vertes, sous condition du respect des conditions définies. Des variantes utilisant d'autres gaz d'adsorption sont proposées.
La méthode reste pertinente tant que la valeur attendue est comprise entre 1 m2/g et 10 m2/g.

Tehnologija jedrskih goriv - Smernice za merjenje specifične površine prahu uranovega oksida po metodi BET (ISO 12800:2017)

Standard ISO 12800:2017 podaja smernice za določanje specifične površine izdelanega prahu uranovega dioksida z volumetričnim ali gravimetričnim določanjem količine adsorbiranega dušika na prahu. Standard lahko uporabimo tudi pri drugih podobnih materialih, npr. pri prahovih U3O8, UO2-PuO2 in drugih telesih s podobno površino, npr. granule prahu ali zeleni peleti, dokler so izpolnjeni opisani pogoji. Vključene so modifikacije, pri katerih se uporabljajo drugi adsorbirani plini.
Metoda je primerna, če je pričakovana vrednost od 1 m2/g do 10 m2/g.

General Information

• Status: Published
• Public Enquiry End Date: 31-Jan-2019
• Publication Date: 02-Jul-2019
• 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: 20-Jun-2019
• Due Date: 25-Aug-2019
• Completion Date: 03-Jul-2019
• Ref Project: EN ISO 12800:2019 - Nuclear fuel technology - Guidelines on the measurement of the specific surface area of uranium oxide powders by the BET method (ISO 12800:2017)

Overview

EN ISO 12800:2019 (ISO 12800:2017) provides guidelines for measuring the specific surface area (SSA) of uranium oxide powders using the BET method (Brunauer–Emmett–Teller). The standard covers volumetric and gravimetric determination of the amount of adsorbed gas-typically nitrogen at liquid‑nitrogen temperature (≈77.4 K)-and applies to as‑fabricated UO2 powders and similar materials (e.g., U3O8, UO2–PuO2, granules or green pellets) when the expected SSA is in the range 1 m2/g to 10 m2/g. Modifications using other adsorbing gases are also discussed.

Key topics and requirements

• Measurement principle: determination of monolayer adsorption from isothermal adsorption curves (BET theory).
• Applicable isotherms: method is intended for materials showing type 2 or type 4 adsorption isotherms.
• Measurement methods: guidance for volumetric, gravimetric, single‑point and multipoint BET determinations; includes a carrier‑gas (dynamic) approach and notes on alternative techniques.
• Sample pre‑treatment: removal of surface contaminants (water, volatiles) by evacuation and controlled heating. The standard gives example pre‑treatment regimens (e.g., heating around 150 °C ±10 °C for a few hours or equivalent conditions; avoid sintering-temperatures > ~350 °C can be detrimental for oxygen‑rich powders).
• Calculation and reporting: instructions for calculating SSA (multipoint and single‑point), precision/accuracy considerations, and required test report contents.
• Assumptions & limitations: nitrogen must not be chemically absorbed or react with the material; pores must be accessible to the adsorbate; BET assumptions about layer energies and surface homogeneity apply.

Practical applications and users

• Nuclear fuel manufacturers: process control and quality assurance during powder production and fabrication of pellets.
• Analytical and metrology laboratories: routine SSA characterization of uranium oxide and mixed‑oxide (MOX) powders.
• R&D teams and material scientists: powder optimization, sintering behavior studies, and formulation development.
• Regulators and auditors: verifying conformity with accepted measurement practices for nuclear fuel technology.

The standard helps ensure consistent, comparable SSA data for feedstock qualification, sinterability prediction, and process control in nuclear fuel production.

Related standards and notes

• EN ISO 12800:2019 is the CEN-adopted European version of ISO 12800:2017.
• Users should consult instrument‑specific guidance and other adsorption/porosimetry standards where appropriate.

Keywords: EN ISO 12800:2019, ISO 12800:2017, BET method, specific surface area, uranium oxide powders, UO2, U3O8, UO2–PuO2, nitrogen adsorption, volumetric measurement, gravimetric measurement.

Standards Content (Sample)

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
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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
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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
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