SIST EN ISO 9271:2024

SLOVENSKI STANDARD
01-september-2024
Dekontaminacija radioaktivno onesnaženih površin - Testiranje
dekontaminacijskih sredstev za tekstil (ISO 9271:2023)
Decontamination of radioactively contaminated surfaces - Testing of decontamination
agents for textiles (ISO 9271:2023)
Dekontamination von radioaktiv kontaminierten Oberflächen - Prüfung von
Dekontaminationswaschmitteln für Textilien (ISO 9271:2023)
Décontamination des surfaces contaminées par la radioactivité - Essai des agents de
décontamination pour les textiles (ISO 9271:2023)
Ta slovenski standard je istoveten z: EN ISO 9271:2024
ICS:
13.280 Varstvo pred sevanjem Radiation protection
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN ISO 9271
EUROPEAN STANDARD
NORME EUROPÉENNE
July 2024
EUROPÄISCHE NORM
ICS 13.280
English Version
Decontamination of radioactively contaminated surfaces -
Testing of decontamination agents for textiles (ISO
9271:2023)
Décontamination des surfaces contaminées par la Dekontamination von radioaktiv kontaminierten
radioactivité - Essai des agents de décontamination Oberflächen - Prüfung von
pour les textiles (ISO 9271:2023) Dekontaminationswaschmitteln für Textilien (ISO
9271:2023)
This European Standard was approved by CEN on 7 July 2024.

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
© 2024 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 9271:2024 E
worldwide for CEN national Members.

Contents Page
European foreword . 3

European foreword
The text of ISO 9271:2023 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 9271:2024 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 January 2025, and conflicting national standards shall
be withdrawn at the latest by January 2025.
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.
Any feedback and questions on this document should be directed to the users’ national standards body.
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 9271:2023 has been approved by CEN as EN ISO 9271:2024 without any modification.

INTERNATIONAL ISO
STANDARD 9271
Second edition
2023-02
Decontamination of radioactively
contaminated surfaces — Testing of
decontamination agents for textiles
Décontamination des surfaces contaminées par la radioactivité —
Essai des agents de décontamination pour les textiles
Reference number
ISO 9271:2023(E)
ISO 9271:2023(E)
© ISO 2023
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 9271:2023(E)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms, definitions and symbols . 1
3.1 Terms and definitions . 2
3.2 Symbols . 3
4 Principle . 3
5 Apparatus . 4
5.1 Beakers . 4
5.2 Radiation detector . . . 4
5.3 Pipettes . 5
5.4 Two polytetrafluoroethylene (PTFE) or quartz ampoules . 5
5.5 Thermostat . 5
5.6 Storage bottles . 5
5.7 Drying cabinet . . 5
5.8 Mounting . 5
5.9 Cage-stirrer apparatus . 6
6 Contamination and decontamination agents . 6
6.1 Contaminant solutions . 6
6.1.1 Composition of contaminant solutions . 6
6.1.2 Preparation of the contaminant solutions. 6
6.1.3 Storage of the contaminant solution . 7
6.2 Decontamination agents . 7
7 Contaminated textile specimen .7
7.1 Reference materials . 7
7.2 Number and dimensions of contaminated textile specimens . 8
8 Procedure .8
8.1 Determining the specific pulse rate of each contaminant solution . 8
8.2 Preparation of the textile specimens . 8
8.3 Contamination . 9
8.3.1 Preparation . 9
8.3.2 Procedure . 9
8.4 Decontamination . 10
8.4.1 Preparation . 10
8.4.2 Procedure . 10
8.5 Determining the residual pulse rate, I . 11
r
9 Calculation of results and assessment of ease of decontamination .11
10 Test report .12
Annex A (informative) Clamp specimen holder .13
Annex B (normative) Cage-stirrer apparatus for decontamination .14
60 137 134
Annex C (informative) Formulae for the preparation of Co and Cs or Cs contaminant
solutions .23
Annex D (informative) Example of a test report .26
Bibliography .28
iii
ISO 9271:2023(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 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.
This second edition cancels and replaces the first edition (ISO 9271:1992), which has been technically
revised.
The main changes are as follows:
— the scope was rephrased and specified;
— opening to further applications;
— adding of symbols of the used measurands;
— improvement of structure;
— improvement in readability;
— adaption to current standards;
— adding a new form in the Annex with description the properties of the agents to be tested.
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
ISO 9271:2023(E)
Introduction
Wherever radioactivity is used, there is a risk that textiles can become contaminated through contact
with radioactivity in solution or airborne radioactivity.
It is normally necessary to remove this contamination to reduce the risk to staff from accidental intake
of the radioactivity on the surface. The ease of decontaminating textiles is therefore an important
parameter to consider when selecting materials to use, e.g., for facilities in the nuclear industry, in
radionuclide laboratories or nuclear medicine facilities.
This document defines a quantitative method under objective conditions for testing the ease of
decontamination of textile fabric. The method enables the comparison of different textile materials to
support decisions on textiles for use in different applications.
For the test, radioactive solutions are deposited onto a sample of the material being studied. The
60 137 134
solutions contain radionuclides commonly found in nuclear industry ( Co, Cs or Cs) and
are in aqueous form. The textiles are then cleaned with detergents or cleansing agent, to be tested,
and the residual activity on the textiles is measured to give a quantitative measure of the ease of
decontamination.
Information obtained from the test method will enable the optimization of the choice of decontamination
agents for textiles. This should result in lower demands for materials and water in laundry systems,
with consequent savings in the cost of radioactive waste processing operations such as filtration,
evaporation, solidification and disposal.
If the customer desires that suitability of their decontamination agents is to be tested with other
radiochemicals containing alpha- and beta- emitting radionuclides, then other procedures and
measurement techniques (like liquid-scintillation-counting) are to be used, which are not described in
this document.
Comparative tests can be carried out with all possible combinations of textile materials and
radionuclides in homogeneous solutions. Inorganic or organic solutions can be used and they should be
based on a solvent which evaporates at room temperature. An assessment of the results of a series of
comparative tests is made on the basis of the mean residual pulse rates.
In order to permit the general qualification of a decontamination agent as a single product, this
60 137 134
document specifies a test and assessment method based on Co and Cs or Cs applied to
internationally standardized cotton fabric. These two radionuclides were selected because they are the
most important sources of contamination in the nuclear industry. The cotton fabric selected is the only
reference material available in this field. The assessment of the result of a single test is made using an
assessment table of final residual pulse rates based on inter-laboratory experiments.
v
INTERNATIONAL STANDARD ISO 9271:2023(E)
Decontamination of radioactively contaminated surfaces —
Testing of decontamination agents for textiles
1 Scope
This document applies to the testing of the decontamination of textiles, which are contaminated by
radioactive materials.
The test method describes the technique to assess the efficiency of decontamination agents
(see ISO 7503-1 and ISO 7503-3).
This document applies to the testing of detergents, which may be used in aqueous solutions for the
purpose of cleaning radioactively contaminated textiles.
60 137
The radionuclides used in this test are those commonly found in the nuclear industry ( Co and Cs
or Cs) in aqueous form. The test can also be adapted for use with other radionuclides and other
chemical forms, depending on the customer requirements, if the solutions are chemically stable and do
not damage the test specimen.
The test method is not suitable if the radionuclide emits low energy gamma rays, like Fe, or low energy
beta or alpha particles that are readily attenuated in the textile fabrics, or if the nuclide has a chemical
or isotopic interaction with the detergent used in the method (e.g. tritium which could be in several
chemical forms).
The test method does not apply to the testing of the ability of detergents to remove non-radioactive dirt.
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.
ISO 2174, Surface active agents — Preparation of water with known calcium hardness
ISO 2267, Surface active agents — Evaluation of certain effects of laundering — Methods of preparation
and use of unsoiled cotton control cloth
ISO 3819, Laboratory glassware — Beakers
ISO 6330, Textiles — Domestic washing and drying procedures for textile testing
ISO 11074, Soil quality — Vocabulary
ISO 80000-10, Quantities and units — Part 10: Atomic and nuclear physics
ISO/IEC Guide 98-3, Uncertainty of measurement — Part 3: Guide to the expression of uncertainty in
me a s ur ement (GUM: 1995)
ISO/IEC Guide 99, International vocabulary of metrology — Basic and general concepts and associated
terms (VIM)
3 Terms, definitions and symbols
For the purposes of this document, the terms and definitions given in ISO 11074, ISO 80000-10,
ISO/IEC Guide 98-3, ISO/IEC Guide 99 and the following apply.
ISO 9271:2023(E)
ISO and IEC maintain terminology 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 Terms and definitions
3.1.1
contamination
radioactive substances deposited on textiles
3.1.2
contaminated textile specimen
pieces of textile reference materials which are contaminated in a specified manner and which are used
to determine the efficiency of decontamination agents
3.1.3
decontamination
complete or partial removal of radioactive contamination (3.1.1) by a deliberate physical, chemical, or
biological process
[SOURCE: ISO 12749-3:2015, 3.7.11.2]
Note 1 to entry: It is preferred that decontamination does not significantly change the characteristics of the
surface.
3.1.4
specific pulse rate
I
s
pulse rate caused in the measuring apparatus under given geometrical conditions by 1 ml of a
contaminant solution
Note 1 to entry: It is expressed in pulses per minute standardized on 1 ml of the contaminant solution. Pulse
rates are derived from count rates applying dead time and background corrections.
3.1.5
residual pulse rate
I
r
pulse rate caused in the measuring apparatus under given geometrical conditions by the residual
radionuclide on the tested side of the specimen after decontamination (3.1.3)
Note 1 to entry: l is expressed in pulses per minute.
r
3.1.6
mean residual pulse rate
l
r
arithmetic mean of the residual pulse rate values obtained for the five test specimens contaminated by
the same radionuclide
Note 1 to entry: It is expressed in pulses per minute.
3.1.7
standardized mean residual pulse rate
corrected value of the mean residual pulse rate (3.1.6)
Note 1 to entry: The correction factor is obtained by dividing a reference value of the specific pulse rate by the
pulse rate of a contaminant solution used in the test.
Note 2 to entry: It is expressed in pulses per minute.
ISO 9271:2023(E)
Note 3 to entry: The purpose of the correction factor is to compensate for variations in specific pulse rates of
contaminant solutions used in different test laboratories.
3.1.8
final residual pulse rate
I
r,fin
60 134 137
arithmetic mean of the standardized mean residual pulse rate (3.1.7) obtained for Co and Cs or Cs
Note 1 to entry: It is expressed in pulses per minute.
Note 2 to entry: is the pulse rate caused in the measuring apparatus under given geometrical conditions by the
residual radionuclide on the tested side of the specimen after decontamination (3.1.3).
3.2 Symbols
For the purposes of this document, the following symbols apply.
A Activity of the radionuclide [Bq]
−1
A Specific activity of the radionuclide [Bq·g ]
S
A Activity of the radionuclide in the contaminant solution [Bq]
E
D Distance between the centre point of the contaminated area and the edge of the sensitive
min
detector cross-section [mm]
h Distance of the contaminated test surface from the detector surface [mm]
m Mass [g]
-1
M Molar mass [kg·mol ]
r Final volume of contaminant solution [ml]
−1
s Activity concentration of stock solution [MBq·ml ]
−1
q Carrier concentration [mol·l ]
−1
τ Carrier concentration of the initial radionuclide solution [mol·l ]
t Time [s]
t Half-life [years]
1/2
−1
u Carrier concentration, in moles per litre [mol·l ]
V Volume [l]
4 Principle
60 137 134
A specimen of the textile material is contaminated using a solution containing Co and Cs or Cs.
The emission from the specimen is measured using a detector. The specimen made from textile reference
material is decontaminated using a solution of the decontamination agent under test. The emission is
measured again and the result is compared to the result of the first measurement to quantify the ease
of decontamination.
60 137 134 −5 −1
Separate contaminant solutions containing Co and Cs or Cs (carrier concentration: 10 mol·l ;
pH 4) are prepared. 100 μl samples of these solutions are counted using a large area radiation detector.
The specific pulse rates of contaminant solutions are calculated using the results from the count.
ISO 9271:2023(E)
Specimens of the material under test are first treated with the contaminant solutions over a defined
area and subsequently decontaminated with demineralized water. The residual pulse rate, I , is
r
determined by measuring the contaminated samples.
The standardized mean residual pulse rates l for each radionuclide are calculated. The arithmetic
r,n
60 137 134
mean of the respective values for Co and Cs or Cs (final residual pulse rate, I ) is used to
r,fin
assess the ease of decontamination by means of a classification which has been compiled empirically.
5 Apparatus
In addition to ordinary laboratory apparatus, the following equipment shall be used for testing the ease
of decontamination of textiles.
5.1 Beakers
Two beakers, of the low-form type, having a capacity of 2 000 ml and in accordance with requirements
given in ISO 3819.
5.2 Radiation detector
A detector and associated electronics are required for determining the pulse rate. Suitable detectors
are solid scintillation (e.g. NaI(Tl), LaBr (Ce), CeBr ) and semi-conductor types selective for gamma-ray
3 3
(see Reference [8]).
NOTE The sensitivity and the efficiency depend on the size of the scintillator crystal or the semi-conductor
detector
The minimum size of the sensitive area of the detector shall be a circle having a diameter of 30 mm, but
in practice, the geometrical requirement specified normally necessitates the use of a larger sensitive
area.
D −12,5
min
To comply with geometrical requirements, the ratio shall not be less than 3,
h
where
D is the smallest distance, in millimetres, from the centre point of the contaminated area, as
min
projected onto the detector cross-section, to the edge of the sensitive detection area
h is the distance, in millimetres, of the contaminated test surface from the detector surface
(see Figure 1).
D −12,5
min
If the geometrical requirement ≥ 3 is not met, a detector having a circular sensitive area of
h
not less than 30 mm in diameter may be used, provided that
a) for the determination of the specific pulse rate (see 8.1), the 100 µl of contaminant solution is
applied to the centre of the textile specimen
b) the net pulse rate of 100 µl of contaminant solution measured under these geometrical conditions
is not less than 200 000 pulses per minute (see 6.1.1, 8.1 and Annex C).
The geometrical requirements for a radiation detector are illustrated in Figure 1.
ISO 9271:2023(E)
Key
1 detector h distance, in millimetres
2 sensitive area of detector D smallest distance, in millimetres
min
3 contaminated area
4 test specimen
Figure 1 — Geometrical requirements for a radiation detector (cross-section)
5.3 Pipettes
Two pipettes with disposable tips, having a capacity of 100 µl.
5.4 Two polytetrafluoroethylene (PTFE) or quartz ampoules
Two polytetrafluoroethylene (PTFE) ampoules for preparation of the contamination solution
or
two quartz ampoules for the activation of the inactive stock solution in the neutron reactor are required.
5.5 Thermostat
A thermostat for setting and maintaining the test temperature at 60 °C.
5.6 Storage bottles
Two polytetrafluoroethylene (PTFE) bottles for storage the radioactive stock solution are required.
NOTE Other fluorinated materials of similar chemical resistance are possible alternatives to
polytetrafluoroethylene (PTFE), such as polytetrafluoroethylene/perfluoropropylene (PTFE/PFP), perfluoro
alkoxyl alkane (PFA) and poly(vinylidene fluoride) (PVDF).
5.7 Drying cabinet
Drying cabinet for drying the textile specimens in their respective holders.
5.8 Mounting
Ten holders for test specimens (5 for each radionuclide), made of poly(methyl methacrylate) (PMMA),
serving as positioning aids for the contamination step (see Annex A).
...