SIST EN ISO 12807:2021
(Main)Safe transport of radioactive materials - Leakage testing on packages (ISO 12807:2018)
Safe transport of radioactive materials - Leakage testing on packages (ISO 12807:2018)
This document specifies gas leakage test criteria and test methods for demonstrating that packages used to transport radioactive materials comply with the package containment requirements defined in the International Atomic Energy Agency (IAEA) Regulations for the Safe Transport of Radioactive Material for:
— design verification;
— fabrication verification;
— preshipment verification;
— periodic verification;
— maintenance verification.
This document describes a method for relating permissible activity release of the radioactive contents carried within a containment system to equivalent gas leakage rates under specified test conditions. This approach is called gas leakage test methodology. However, in this document it is recognized that other methodologies might be acceptable, provided that they demonstrate that any release of the radioactive contents will not exceed the regulatory requirements, and subject to agreement with the competent authority.
This document provides both overall and detailed guidance on the complex relationships between an equivalent gas leakage test and a permissible activity release rate. Whereas the overall guidance is universally agreed upon, the use of the detailed guidance shall be agreed upon with the competent authority during the Type B(U), Type B(M) or Type C packages certification process.
It should be noted that, for a given package, demonstration of compliance is not limited to a single methodology.
While this document does not require particular gas leakage test procedures, it does present minimum requirements for any test that is to be used. It is the responsibility of the package designer or consignor to estimate or determine the maximum permissible release rate of radioactivity to the environment and to select appropriate leakage test procedures that have adequate sensitivity.
This document pertains specifically to Type B(U), Type B(M) or Type C packages for which the regulatory containment requirements are specified explicitly.
Kernbrennstofftechnologie - Sicherer Transport von radioaktivem Material - Dichtheitsprüfung der Verpackung (ISO 12807:2018)
Dieses Dokument legt Prüfkriterien und Prüfverfahren für die Messung der Gasleckage fest, um nachzuweisen, dass Versandstücke für den Transport radioaktiven Materials die Anforderungen an sichere Verpackungen im Dokument Regulations for the Safe Transport of Radioactive Material der International Atomic Energy Agency (IAEA) erfüllen, für die
- Designverifizierung,
- Verifizierung bei der Fertigung,
- Verifizierung vor Versand,
- regelmäßige Verifizierung, und
- Verifizierung bei Wartung.
Dieses Dokument beschreibt ein Verfahren, mit der die zulässige Aktivitätsfreisetzung radioaktiven Inhalts in einem Umschließungssystem unter vorgegebenen Prüfbedingungen zu äquivalenten Gasleckageraten in Bezug gesetzt werden kann. Dieser Ansatz wird als die Gasleckage-Prüfmethodik bezeichnet. Jedoch wird in diesem Dokument anerkannt, dass auch andere Verfahren zulässig sein könnten, sofern mit ihnen nachgewiesen werden kann, dass eine Freisetzung des radioaktiven Inhalts die behördlichen Anforderungen nicht übersteigt und diese mit der zuständigen Behörde abgestimmt werden.
Dieses Dokument stellt sowohl eine allgemeine als auch eine detaillierte Anleitung zu den komplexen Beziehungen zwischen einer Prüfung der äquivalenten Gasleckage und einer zulässigen Aktivitäts-freisetzungsrate bereit. Während die allgemeine Anleitung allgemein anerkannt ist, muss die Anwendung der detaillierten Anleitung mit der zuständigen Behörde während der Zertifizierung von Versandstücken Typ B(U), Typ B(M) oder Typ C vereinbart werden.
Es wird darauf hingewiesen, dass der Nachweis der Erfüllung der Anforderung nicht auf eine einzelne Methodik beschränkt ist.
Dieses Dokument verlangt keine bestimmten Prüfverfahren für Gasleckagen, legt jedoch Mindestanforderungen für jede Prüfung fest, die angewandt wird. Der Konstrukteur oder Lieferant des Versandstücks ist für die Abschätzung oder Bestimmung der maximal zulässigen Freisetzungsrate von Radioaktivität in die Umgebung und für die Wahl der geeigneten Leckage-Prüfverfahren, die eine angemessene Empfindlichkeit aufweisen, verantwortlich.
Dieses Dokument bezieht sich gezielt auf Versandstücke Typ B(U), Typ B(M) oder Typ C, für die die behördlich festgesetzten Anforderungen an eine dichte Umschließung explizit festgelegt sind.
Sûreté des transports de matières radioactives - Contrôle de l'étanchéité des colis (ISO 12807:2018)
Le présent document donne les critères applicables aux essais d'étanchéité au gaz et les méthodes de contrôle permettant de vérifier que les colis utilisés pour transporter les matières radioactives sont conformes aux exigences pour le confinement définies dans le Règlement de transport des matières radioactives de l'Agence internationale de l'énergie atomique (AIEA), du point de vue des:
— contrôles à la conception;
— contrôles en cours de fabrication;
— contrôles avant expédition;
— contrôles périodiques;
— contrôles de maintenance.
Le présent document décrit une méthodologie qui permet d'établir une relation entre le relâchement d'activité admissible du contenu radioactif transporté dans une enveloppe de confinement et les flux de fuite équivalents d'un gaz, dans des conditions d'essai données. II s'agit de la méthodologie de contrôle d'étanchéité au gaz. Cependant, le présent document admet que d'autres méthodologies puissent être suivies, avec l'accord de l'autorité compétente, à condition qu'elles démontrent que toute perte de contenu radioactif n'excédera pas les exigences réglementaires.
Le présent document fournit des lignes directrices à la fois générales et détaillées sur les relations complexes entre un essai de flux de fuite équivalent et le taux admissible de relâchement d'activité. Étant donné que les lignes directrices générales sont reconnues universellement, l'utilisation des lignes directrices détaillées doit faire l'objet d'un accord avec l'autorité compétente lors de la certification des colis de type B(U), B(M) ou C.
II convient de noter que la démonstration de la conformité d'un colis donné n'est pas limitée à la mise en œuvre d'une seule méthodologie.
Bien que le présent document n'impose pas de méthode spécifique d'essai d'étanchéité au gaz, il indique des exigences minimales pour toute méthode susceptible d'être utilisée. II incombe au concepteur, ou à l'expéditeur du colis, d'estimer ou de déterminer, le taux de relâchement maximal admissible de matière radioactive dans l'environnement et de choisir des procédures d'essai d'étanchéité appropriées qui présentent la sensibilité requise.
Le présent document s'applique tout particulièrement aux colis de type B(U), B(M) ou C pour lesquels les exigences réglementaires pour le confinement sont spécifiées explicitement.
Varen prevoz radioaktivnih snovi - Preskušanje tesnjenja embalaže (ISO 12807:2018)
General Information
Standards Content (Sample)
SLOVENSKI STANDARD
01-april-2021
Varen prevoz radioaktivnih snovi - Preskušanje tesnjenja embalaže (ISO
12807:2018)
Safe transport of radioactive materials - Leakage testing on packages (ISO 12807:2018)
Kernbrennstofftechnologie - Sicherer Transport von radioaktivem Material -
Dichtheitsprüfung der Verpackung (ISO 12807:2018)
Sûreté des transports de matières radioactives - Contrôle de l'étanchéité des colis (ISO
12807:2018)
Ta slovenski standard je istoveten z: EN ISO 12807:2021
ICS:
13.280 Varstvo pred sevanjem Radiation protection
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 12807
EUROPEAN STANDARD
NORME EUROPÉENNE
February 2021
EUROPÄISCHE NORM
ICS 13.280; 27.120.30
English Version
Safe transport of radioactive materials - Leakage testing on
packages (ISO 12807:2018)
Sûreté des transports de matières radioactives - Kernbrennstofftechnologie - Sicherer Transport von
Contrôle de l'étanchéité des colis (ISO 12807:2018) radioaktivem Material - Dichtheitsprüfung der
Verpackung (ISO 12807:2018)
This European Standard was approved by CEN on 18 January 2021.
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
© 2021 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 12807:2021 E
worldwide for CEN national Members.
Contents Page
European foreword . 3
European foreword
The text of ISO 12807:2018 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 12807:2021 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 2021, and conflicting national standards shall
be withdrawn at the latest by August 2021.
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 12807:2018 has been approved by CEN as EN ISO 12807:2021 without any modification.
INTERNATIONAL ISO
STANDARD 12807
Second edition
2018-09
Safe transport of radioactive
materials — Leakage testing on
packages
Sûreté des transports de matières radioactives — Contrôle de
l'étanchéité des colis
Reference number
ISO 12807:2018(E)
©
ISO 2018
ISO 12807:2018(E)
© ISO 2018
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.
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Phone: +41 22 749 01 11
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Published in Switzerland
ii © ISO 2018 – All rights reserved
ISO 12807:2018(E)
Contents Page
Foreword .v
Introduction .vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Symbols and units . 4
5 Regulatory requirements . 7
5.1 Relevant regulations. 7
5.2 Regulatory containment requirements . 7
6 Procedure for meeting the requirements of this document . 7
6.1 General . 7
6.2 Quality management system . 8
6.3 Procedure . 8
6.3.1 General. 8
6.3.2 Determination of permissible activity release rates . 9
6.3.3 Determination of standardized leakage rates.10
6.3.4 Determination of permissible test leakage rates for each verification stage .10
6.3.5 Selection of appropriate test methods .10
6.3.6 Performance of test and record of results . .10
7 Determination of permissible activity release rates .10
7.1 Step 1: List the radioactive contents, A .
i 10
7.2 Step 2: Determine the total releasable activity, RI .
T 10
7.3 Step 3: Determine the maximum permissible activity release rates, R . 11
8 Determination of standardized leakage rates .11
8.1 General .11
8.2 Step 4: Determine the activity release rate due to permeation, RP . 12
8.3 Step 5: Determine the maximum permissible activity release rate due to leakage, RG . 12
8.4 Step 6: Determine the activity per unit volume of the containment system medium, C . 12
8.5 Step 7: Determine the maximum permissible volumetric leakage rate of the medium, L . 12
8.6 Step 8: Determine the maximum permissible equivalent capillary leak diameter, D . 12
8.7 Step 9: Determine the permissible standardized leakage rate, Q .
SLR 13
9 Containment-system verification requirements .13
9.1 Containment-system verification stages .13
9.1.1 General.13
9.1.2 Design verification .14
9.1.3 Fabrication verification .14
9.1.4 Preshipment verification .14
9.1.5 Periodic verification .15
9.1.6 Maintenance verification .15
9.2 Verification requirements .15
9.2.1 General.15
9.2.2 Step 10: Determine permissible test leakage rate for each verification
stage, Q , Q , Q Q Q and Q .
TDA TDN TF, TS, TP TM 15
9.2.3 Step 11: Select appropriate test methods .15
10 Leakage test procedure requirements .16
10.1 General .16
10.2 Step 12: Perform tests and record results .16
10.3 Test sensitivity .16
10.4 Test procedure requirements .16
10.4.1 General.16
ISO 12807:2018(E)
10.4.2 Testing .16
Annex A (informative) Preferred leakage test methods .17
Annex B (informative) Methods of calculation.31
Annex C (informative) Conversion tables .36
Annex D (informative) Worked examples .37
Annex E (informative) Rationale .72
Bibliography .85
iv © ISO 2018 – All rights reserved
ISO 12807:2018(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 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 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 5, Nuclear installations, processes and technologies.
This second edition cancels and replaces the first edition (ISO 12807:1996), which has been technically
revised.
In this document, the word “shall” denotes a requirement; the word “should” denotes a recommendation;
and the word “may” denotes permission, neither a requirement nor a recommendation. Imperative
statements also denote requirements. To conform with this document, all operations shall be performed
in accordance with its requirements, but not necessarily with its recommendations.
The words “can”, “could” and “might” denote possibility rather than permission.
The word “will” denotes that an event is certain to occur rather than a requirement.
ISO 12807:2018(E)
Introduction
The International Atomic Energy Agency (IAEA) Regulations for the Safe Transport of Radioactive
Material specify permitted release of radioactivity under normal and accident conditions of transport,
in terms of activity per unit of time, for Type B(U), Type B(M) and Type C packages used to transport
radioactive materials. Generally, it is not practical to measure activity release directly. The usual
method used is to relate activity release to non-radioactive fluid leakage, for which several leakages test
procedures are available. The appropriate procedure will depend on its sensitivity and its application
to a specific package.
The regulations specify permissible activity release for normal and accident conditions of transport.
These activity release limits can be expressed in maximum permissible activity release rates for the
radioactive material carried within a containment system.
In general, it is not feasible to demonstrate that the activity release limits are not exceeded by direct
measurement of activity release. In practice, the most common method to prove that a containment
system provides adequate containment is to carry out an equivalent gas leakage rate test.
vi © ISO 2018 – All rights reserved
INTERNATIONAL STANDARD ISO 12807:2018(E)
Safe transport of radioactive materials — Leakage testing
on packages
1 Scope
This document specifies gas leakage test criteria and test methods for demonstrating that packages
used to transport radioactive materials comply with the package containment requirements defined
in the International Atomic Energy Agency (IAEA) Regulations for the Safe Transport of Radioactive
Material for:
— design verification;
— fabrication verification;
— preshipment verification;
— periodic verification;
— maintenance verification.
This document describes a method for relating permissible activity release of the radioactive contents
carried within a containment system to equivalent gas leakage rates under specified test conditions.
This approach is called gas leakage test methodology. However, in this document it is recognized that
other methodologies might be acceptable, provided that they demonstrate that any release of the
radioactive contents will not exceed the regulatory requirements, and subject to agreement with the
competent authority.
This document provides both overall and detailed guidance on the complex relationships between an
equivalent gas leakage test and a permissible activity release rate. Whereas the overall guidance is
universally agreed upon, the use of the detailed guidance shall be agreed upon with the competent
authority during the Type B(U), Type B(M) or Type C packages certification process.
It should be noted that, for a given package, demonstration of compliance is not limited to a single
methodology.
While this document does not require particular gas leakage test procedures, it does present minimum
requirements for any test that is to be used. It is the responsibility of the package designer or consignor
to estimate or determine the maximum permissible release rate of radioactivity to the environment
and to select appropriate leakage test procedures that have adequate sensitivity.
This document pertains specifically to Type B(U), Type B(M) or Type C packages for which the
regulatory containment requirements are specified explicitly.
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.
International Atomic Energy Agency (IAEA). Regulations for the Safe Transport of Radioactive Material
3 Terms and definitions
For the purposes of this document, the terms and definitions given in the International Atomic Energy
Agency (IAEA), Regulations for the Safe Transport of Radioactive Material and the following apply.
ISO 12807:2018(E)
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https: //www .iso .org/obp
— IEC Electropedia: available at https: //www .electropedia .org/
3.1
activity release rate
loss of radioactive contents per unit time through leaks or permeable walls of a containment system
3.2
blockage mechanism
mechanism by which radioactive material might be retained within a containment system due to
blockage of potential leakage paths by solid or liquid material
3.3
competent authority
any national or international authority designated or recognized as such for any purpose in connection
with the International Atomic Energy Agency (IAEA) Regulations for the Safe Transport of Radioactive
Material and other applicable regulations
3.4
containment system
assembly of components of the packaging intended to retain the radioactive material during transport
3.5
gas leakage test methodology
method of specifying a gas leakage test which relates permissible activity release rates of the radioactive
contents carried within a containment system to equivalent gas leakage rates under specified test
conditions
3.6
leak
any unwanted opening or openings through a containment system that could permit the escape of the
contents
3.7
leakage
transfer of a material from the containment system to the environment through a leak or leaks
Note 1 to entry: See also permeation (3.14).
3.8
leakage rate
quantity of solid particles, liquids or gases passing through leaks per unit time
Note 1 to entry: The term leakage rate can refer to the radioactive material (gas, liquid, solid or any mixture of
these) or to the test fluid.
Note 2 to entry: The dimensions of the rate of solid leakage are mass divided by time. The dimensions of the
rate of liquid leakage can be mass divided by time or volume divided by time. The dimensions of the rate of gas
leakage are the product of pressure and volume (this is a mass-like unit) divided by time at a known temperature.
3.9
leaktight
general term indicating that a containment system meets the required level of containment for
particular contents
Note 1 to entry: See Clause 8 in Annex E.
2 © ISO 2018 – All rights reserved
ISO 12807:2018(E)
3.10
medium
any fluid, which might or might not be radioactive itself, which could carry radioactive material through
a leak or leaks
3.11
molecular flow
flow of gas through a leak under conditions such that the mean free path is greater that the largest
dimension of a transverse section of the leak
Note 1 to entry: The rate of molecular flow depends on the partial pressure gradient.
3.12
package
packaging together with its radioactive contents as presented for transport
3.13
packaging
assembly of components necessary to enclose the radioactive contents completely
3.14
permeation
passage of a fluid through a solid permeable barrier (even if there are no leaks) by adsorption-diffusion-
desorption mechanisms
Note 1 to entry: Permeation should not be considered as a release of activity unless the fluid itself is radioactive.
In this document, permeation is applied only to gases.
3.15
permeation rate
quantity of gases passing through permeable walls per unit time
Note 1 to entry: The permeation rate depends on the partial pressure gradient.
3.16
qualitative
refers to leakage test procedures which detect the presence of a leak but do not measure leakage rate or
total leakage
3.17
quantitative
leakage test procedures which measure total leakage rate(s) from a containment system or from
parts of it
3.18 Sensitivity
3.18.1
sensitivity of a leakage detector
minimum usable response of the detector to tracer fluid leakage, that is, the leakage rate that will
produce a repeatable change in the detector reading
3.18.2
sensitivity of a leakage test procedure
minimum detectable leakage rate that the test procedure is capable of detecting
ISO 12807:2018(E)
3.19
standardized leakage rate
SLR
leakage rate, evaluated under known conditions, normalized to the flow of dry air at reference conditions
of upstream pressure 1,013 × 10 Pa, downstream pressure 0,0 Pa and temperature of 298 K (25 °C)
3 −1
Note 1 to entry: The units for standardized leakage rate are written as Pa·m ·s SLR.
3.20
standardized helium leakage rate
SHeLR
helium leakage rate, evaluated under known conditions, normalized to the flow of dry helium at
reference conditions of upstream pressure 1,013 × 10 Pa, downstream pressure 0,0 Pa and temperature
of 298 K (25 °C)
3 −1
Note 1 to entry: The units for standardized helium leakage rate are written as Pa·m ·s (SHeLR).
3.21
test gas or tracer gas
gas that is used to detect leakage or measure leakage rates
3.22
viscous flow
continuous flow of gas through a leak under conditions such that the mean free path is very small in
comparison with the smallest dimension of a transverse section of the leak
Note 1 to entry: This flow may be either laminar or turbulent. Viscous flow depends upon total pressure gradient.
4 Symbols and units
The following symbols and units are used in this document.
Symbol Definition Unit
A Activity of radionuclide i Bq
i
A Quantity (activity) of radioactive material, other than special-form radioac- Bq
tive material, as defined in the applicable documents listed in the Interna-
tional Atomic Energy Agency (IAEA) Regulations for the Safe Transport of
Radioactive Material
A A value of radionuclide i Bq
2i 2
a Capillary length/leakage hole length m
−3
C Average activity per unit volume; the symbol is used to simplify Figure 1 and Bq·m
represents the use of either C or C
A N
−3
C Average activity per unit volume of the medium that could escape from the Bq·m
A
containment system under accident conditions of transport
−3
C Average activity per unit volume of the medium that could escape from the Bq·m
N
containment system under normal conditions of transport
D Capillary diameter/leakage hole diameter m
D Maximum permissible diameter; the symbol is used to simplify Figure 1 and m
represents the use of either D or D
A N
D Maximum permissible equivalent capillary leak diameter under accident m
A
conditions of transport
D Bubble diameter m
B
D Maximum permissible equivalent capillary leak diameter under normal m
N
conditions of transport
FC Release fraction of radionuclide i from the radioactive contents into the con- —
iA
tainment system under accident conditions of transport
4 © ISO 2018 – All rights reserved
ISO 12807:2018(E)
Symbol Definition Unit
FC Release fraction of radionuclide i from the radioactive contents into the con- —
iN
tainment system under normal conditions of transport
FE Fraction of radionuclide i which is available for release from the containment —
iA
system into the environment under accident conditions of transport
FE Fraction of radionuclide i which is available for release from the containment —
iN
system into the environment under normal conditions of transport
−2
g Acceleration due to gravity g = 9,81 m·s
−1 −2
g Constant g = 1 kg m N ·s
0 0
H Test duration s
h Liquid height m
3 −1
L Volumetric leakage rate m ·s
3 −1
L Maximum permissible volumetric leakage rate; the symbol is used to m ·s
simplify Figure 1 and represents the use of either L or L
A N
3 −1
L Maximum permissible volumetric leakage rate of the medium at pressure p , m ·s
A A
under accident conditions of transport
3 −1
L Maximum permissible volumetric leakage rate of the medium at pressure p , m ·s
N N
under normal conditions of transport
−1
M Relative molecular mass kg·mol
−1
M Relative molecular mass of component i kg·mol
i
−1
M Relative molecular mass of mixture kg·mol
mix
p Containment system pressure under accident conditions of transport Pa
A
p Containment system pressure under normal conditions of transport Pa
N
p Downstream pressure Pa
d
p Partial pressure of one component i of gas mixture Pa
i
p Total pressure of gas mixture Pa
mix
p Reference pressure p = 1,013 × 10 Pa
s s
p Partial pressure of tracer gas Pa
t
p Upstream pressure Pa
u
p Gas pressure at start of test Pa
p Gas pressure at end of test Pa
3 −1
Q Leakage rate Pa·m ·s
3 −1
Q Standardized leakage rate; the symbol is used to simplify Figure 1 and Pa·m ·s
SLR
represents the use of either Q or Q
A(SLR) N(SLR)
3 −1
Q The permissible leakage rate of the medium under accident conditions of Pa·m ·s
A
transport and is calculated from L
A
3 −1
Q The permissible standardized leakage rate (SLR) under accident conditions Pa·m ·s
A(SLR)
of transport
3 −1
Q Leakage rate for molecular flow Pa·m ·s
m
3 −1
Q Leakage rate for gas mixture Pa·m ·s
mix
3 −1
Q The permissible leakage rate of the medium under normal conditions of Pa·m ·s
N
transport and is calculated from L
N
3 −1
Q The permissible standardized leakage rate (SLR) under normal conditions of Pa·m ·s
N(SLR)
transport
3 −1
Q Permeation rate Pa·m ·s
p
3 −1
Q The permissible test leakage rate of the tracer or test gas that is related to Pa·m ·s
TDA
accident conditions of transport at the design verification stage and is deter-
mined from Q
A(SLR)
ISO 12807:2018(E)
Symbol Definition Unit
3 −1
Q The permissible test leakage rate of the tracer or test gas that is related to Pa·m ·s
TDN
normal conditions of transport at the design verification stage and is deter-
mined from Q
N(SLR)
3 −1
Q The permissible test leakage rate of the tracer gas at the fabrication verifica- Pa·m ·s
TF
tion stage
3 −1
Q The permissible test leakage rate of the tracer gas at the maintenance verifi- Pa·m ·s
TM
cation stage
3 −1
Q The permissible test leakage rate of the tracer gas at the periodic Pa·m ·s
TP
verification stage
3 −1
Q The permissible test leakage rate of the tracer gas at the preshipment Pa·m ·s
TS
vérification stage
3 −1
Q Leakage rate for viscous flow Pa·m ·s
v
−1 −1
R Universal gas constant R = 8,31 J mol K
−1
R Maximum permissible activity release rate; the symbol is used to simplify Bq·s
Figure 1 and represents the use of either R or R
A N
−1
R Maximum permissible activity release rate of the contents under accident Bq·s
A
conditions of transport
−1
R Maximum permissible activity release rate of the contents under normal Bq·s
N
conditions of transport
−1
RG Maximum permissible activity release rate of the gas contents; the symbol is Bq·s
used to simplify Figure 1 and represents the use of either RG or RG
A N
−1
RG Maximum permissible activity release rate of the gas contents under acci- Bq·s
A
dent conditions of transport after allowing for permeation
−1
RG Maximum permissible activity release rate of the gas contents under normal Bq·s
N
conditions of transport after allowing for permeation
RI Releasable activity of radionuclide i under accident conditions of transport Bq
iA
RI Releasable activity of radionuclide i under normal conditions of transport Bq
iN
RI Total releasable activity for all radionuclides; the symbol is used to simplify Bq
T
Figure 1 and represents the use of either RI or RI
TA TN
RI Total releasable activity for all radionuclides under accident conditions of Bq
TA
transport
RI Total releasable activity for all radionuclides under normal conditions of Bq
TN
transport
−1
RP Activity release rate due to permeation; the symbol is used to simplify Bq·s
Figure 1 and represents the use of either RP or RP
A N
−1
RP Activity release rate due to permeation under accident conditions of transport Bq·s
A
−1
RP Activity release rate due to permeation under normal conditions of transport Bq·s
N
3 −1
S Leakage rate sensitivity Pa·m ·s
3 −1
SHeLR Standardized helium leakage rate Pa·m ·s SHeLR
3 −1
SLR Standardized leakage rate Pa·m ·s SLR
T Fluid absolute temperature K
T Reference temperature T = 298 K
0 0
T Gas temperature at start of test K
T Gas temperature at end of test K
−1
u Velocity m·s
V Gas volume m
V Volume of medium under accident conditions of transport m
A
V Volume of medium under normal conditions of transport m
N
μ Dynamic viscosity of fluid Pa·s
6 © ISO 2018 – All rights reserved
ISO 12807:2018(E)
Symbol Definition Unit
μ Viscosity of component i Pa·s
i
μ Viscosity of mixture Pa·s
mix
−1
v Bubble-generation rate s
−3
ρ Density kg m
−3
ρ Gas density kg m
g
−3
ρ Liquid density kg m
l
−1
σ Liquid surface tension N m
5 Regulatory requirements
5.1 Relevant regulations
See 5.1 in Annex E for further information on relevant regulations.
5.2 Regulatory containment requirements
See 5.2 in Annex E for further information on the Type B(U), Type B(M) or Type C packages containment
requirements.
6 Procedure for meeting the requirements of this document
6.1 General
Compliance with package containment requirements may be demonstrated either by measurement
of the radioactive-contents release rate or by other methods. This document shows how the package
containment requirements can be demonstrated by an equivalent gas leakage test. All measured test
leakage rates shall be correlated to the potential release of the contained material by performance
of tests on prototypes or models, reference to previous demonstrations, calculations or reasoned
arguments.
This document is based on the following premises.
a) The radioactive material which could be released from the package could be in any one or any
combination of the following forms:
— liquid;
— gas;
— solid;
— liquids with solids in suspension;
— particulate solids in a gas (aerosols).
The maximum permissible activity release rate can be expressed in terms of a maximum
permissible leak diameter when the physical form and properties of the radioactive contents are
taken into account.
b) The assumption of steady-state condition is an appropriate approximation.
c) Gas leakage test procedure can be used to measure gas flow rates. These rates can be related
mathematically to the diameter of a single straight capillary which in most cases is considered to
conservatively represent a leak or leaks.
ISO 12807:2018(E)
d) Gas leakage test procedures can be used to demonstrate compliance with regulatory containment
requirements when the diameter of the single straight capillary associated with the leakage test
from 6.1 c) is equal to or smaller than the maximum permissible leak diameter from 6.1 a).
For activity release, or retention considerations, according to this document, the phenomena of viscous
flow, molecular flow, permeation and blockage should be considered.
6.2 Quality management system
A management system, based on international, national or other standards, shall be established
and implemented. To ensure the consistent quality of the activities described in this document, the
implementation of ISO 9001:2015 is advised.
See 6.2 in Annex E for further information on the regulatory requirements on the management system.
6.3 Procedure
6.3.1 General
Using the flow chart in Figure 1 as a guide, the procedure below shall be used. The text within each box
in the flow chart indicates the result of the particular step.
Steps 1 to 8 in Figure 1 pertain to containment of the radioactive contents, while Steps 10 to 12 pertain
to leakage of a test gas. Step 9 is a reference step which links containment of the radioactive contents to
the leakage of a test gas.
Because the releasable radioactive material might be in the form of gas, liquid or solid, or a combination
of these, it is necessary to follow the appropriate part of the procedure below, as applicable to the form
of the radioactive material, to obtain the permissible standardized leakage rates.
Figure 1 has been prepared for the general case. In some cases, it is not necessary to complete all the
steps, for example, in the case of a single radionuclide in liquid form. In other cases, such as a mixture
of radioactive materials that are in different forms, it might be necessary to repeat some steps in a
reiterative fashion. However, for any of these cases it will be necessary to complete the appropriate
steps in Figure 1 for both normal and accident conditions of transport.
8 © ISO 2018 – All rights reserved
ISO 12807:2018(E)
Figure 1 — Flow chart for gas leakage test methodology
6.3.2 Determination of permissible activity release rates
The inventory of the releasable radioactive contents shall be identified and the releasable contents shall
be compared to the regulatory containment requirements. See Steps 1 to 3 in Figure 1 and Clause 7.
ISO 12807:2018(E)
6.3.3 Determination of standardized leakage rates
The permissible activity release rates shall be converted to equivalent standardized leakage rates.
See Steps 4 to 9 in Figure 1 and Clause 8.
6.3.4 Determination of permissible test leakage rates for each verification stage
The appropriate gas leakage rates shall be determined for the design, fabrication, preshipment, periodic
and maintenance verification stages. See Step 10 in Figure 1 and 9.2.
6.3.5 Selection of appropriate test methods
The appropriate gas leakage test methods shall be selected for the design, fabrication, preshipment,
periodic and maintenance verification stages. See Step 11 in Figure 1 and 9.2.
6.3.6 Performance of test and record of results
The required tests shall be performed and the results shall be recorded. See Step 12 in Figure 1 and
Clause 10.
7 Determination of permissible activity release rates
Permissible activity release rates shall be determined by following Steps 1 to 3 for both normal and
accident conditions of transport.
7.1 Step 1: List the radioactive contents, A
i
This gives an inventory of the radioactive contents and includes the activity and physical characteristics
for each radionuclide. It could be necessary to consider the contents as separate phases, i.e. liquids, gases
and solids. Aerosols can be considered as gases. Fine particles in solution can be considered as a liquid.
When it is impractical to determine actual radioactive contents, the bounding radioactive contents
shall be estimated by the user and shall be acceptable to the competent authority.
7.2 Step 2: Determine the total releasable activity, RI
T
In some cases, the radioactive contents might be contained by more than one container in the
containment system. An irradiated fuel rod assembly in a transport packaging is an example of this
situation. Then, for either normal or accident conditions of transport, only a fraction of the radioactive
contents might be released from the innermost container into the containment system FC , FC and,
iN iA
of this fraction, only another fraction may be available for release from the containment system to
the environment, FE , FE . The numerical value of any release fraction will depend on the specific
iN iA
radionuclide and, if the radioactive contents consist of a mixture of radionuclides, many release fraction
values could result. Also, release fraction values for normal conditions of transport might differ from
those for accident conditions of transport, even for the same radionuclide.
The releasable fractions depend upon such factors as:
a) the chemical and physical forms of the materials within the containment system, for normal and
accident conditions of transport;
b) the possible release modes, such as permeation of gases, mobility of aerosols or particulates,
reactions with water or other materials present in the system, and solubility;
c) the maximum temperature, pressure, vibration, mechanical strains or distortions, and the like, to
which the contained material would be subjected for normal and accident conditions of transport.
These shall be determined by the performance of tests on prototypes or models, by reference to
previous demonstrations, calculations, or a reasoned argument.
10 © ISO 2018 – All rights reserved
ISO 12807:2018(E)
Where a release fraction cannot be quantified, a value of 1,0 shall be assumed. The values of the release
fractions normally require agreement with the competent authority.
For normal conditions of transport, the releasable activity of radionuclide i, RI , in becquerels, is:
iN
RI =×FC FE ×A
iiNN iiN
and for the total inventory
RI =Σ RI
TN iiN
Similarly, for accident conditions of transport, the releasable activity of radionuclide i, RI , in
iA
becquerels is:
RI =×FC FE ×A
iiAA iiA
and for the total inventory
RI =Σ RI
TA iiA
7.3 Step 3: Determine the maximum permissible activity release rates, R
The data from Steps 1 and 2 identify the radionuclides that could be released from the package and their
physical form. Then, for any radionuclide, the A value shall be established or, in the case of mixtures,
an equivalent A value shall be used (see paragraph 405 in the 2012 Edition of the International Atomic
Energy Agency (IAEA) Regulations for the Safe Transport
...
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