EN IEC 62694:2024

SLOVENSKI STANDARD
01-maj-2024
Instrumenti za zaščito pred sevanjem - Nahrbtni detektor sevanja (BRD) za
odkrivanje nezakonitega prometa z radioaktivnimi snovmi (IEC 62694:2022)
Radiation protection instrumentation - Backpack-type radiation detector (BRD) for the
detection of illicit trafficking of radioactive material (IEC 62694:2022)
Strahlenschutz-Messgeräte - Rucksack-Strahlungsdetektor für den Nachweis von
unerlaubt transportiertem radioaktivem Material (IEC 62694:2022)
Instrumentation pour la radioprotection - Détecteur de rayonnement de type sac à dos
(BRD) pour la détection du trafic illicite des matières radioactives (IEC 62694:2022)
Ta slovenski standard je istoveten z: EN IEC 62694:2024
ICS:
13.280 Varstvo pred sevanjem Radiation protection
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD EN IEC 62694

NORME EUROPÉENNE
EUROPÄISCHE NORM February 2024
ICS 13.280 Supersedes EN 62694:2016
English Version
Radiation protection instrumentation - Backpack-type radiation
detector (BRD) for the detection of illicit trafficking of radioactive
material
(IEC 62694:2022)
Instrumentation pour la radioprotection - Détecteur de Strahlenschutz-Messgeräte - Rucksack-Strahlungsdetektor
rayonnement de type sac à dos (BRD) pour la détection du für den Nachweis von unerlaubt transportiertem
trafic illicite des matières radioactives radioaktivem Material
(IEC 62694:2022) (IEC 62694:2022)
This European Standard was approved by CENELEC on 2024-01-22. CENELEC 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 CENELEC 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 CENELEC member into its own language and notified to the CEN-CENELEC Management Centre has the
same status as the official versions.
CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic,
Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the
Netherlands, Norway, Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Türkiye and the United Kingdom.

European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2024 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Ref. No. EN IEC 62694:2024 E
European foreword
This document (EN IEC 62694:2024) consists of the text of IEC 62694:2022 prepared by IEC/SC 45B
“Radiation protection instrumentation” of IEC/TC 45 "Nuclear instrumentation".
The following dates are fixed:
• latest date by which this document has to be (dop) 2025-01-22
implemented at national level by publication of
an identical national standard or by
endorsement
• latest date by which the national standards (dow) 2027-01-22
conflicting with this document have to be
withdrawn
This document supersedes EN 62694:2016 and all of its amendments and corrigenda (if any).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CENELEC 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 committee. A
complete listing of these bodies can be found on the CENELEC website.
Endorsement notice
The text of the International Standard IEC 62694:2022 was approved by CENELEC as a European
Standard without any modification.
In the official version, for Bibliography, the following notes have to be added for the standard indicated:
IEC 60846-1 NOTE Approved as EN 60846-1
IEC 61526 NOTE Approved as EN 61526
IEC 62244 NOTE Approved as EN IEC 62244
IEC 62327 NOTE Approved as EN IEC 62327
IEC 62401 NOTE Approved as EN IEC 62401
IEC 62484 NOTE Approved as EN IEC 62484
IEC 62533 NOTE Approved as EN 62533
IEC 62534 NOTE Approved as EN 62534
IEC 62618 NOTE Approved as EN 62618
IEC 63121 NOTE Approved as EN IEC 63121
Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications
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.
NOTE 1  Where an International Publication has been modified by common modifications, indicated by (mod), the
relevant EN/HD applies.
NOTE 2  Up-to-date information on the latest versions of the European Standards listed in this annex is available
here: www.cencenelec.eu.
Publication Year Title EN/HD Year
IEC 60050-395 2014 International Electrotechnical Vocabulary - - -
Part 395: Nuclear instrumentation: Physical
phenomena, basic concepts, instruments,
systems, equipment and detectors
+ A1 2016 - -
+ A2 2020 - -
IEC 60068-2-11 - Environmental testing - Part 2-11: Tests - EN IEC 60068-2-11 2021
Test Ka: Salt mist
IEC 60079-11 - Electrical apparatus for explosive gas - -
atmospheres - Part 11: Intrinsic safety "i"
IEC 62706 - Radiation protection instrumentation - - -
Environmental, electromagnetic and
mechanical performance requirements
IEC 62755 - Radiation protection instrumentation - Data - -
format for radiation instruments used in the
detection of illicit trafficking of radioactive
materials
UL 913 - Standard for Intrinsically Safe Apparatus and - -
Associated Apparatus for Use in Class I, II,
III, Division 1, Hazardous (Classified)
Locations
IEC 62694 ®
Edition 2.0 2022-11
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Radiation protection instrumentation – Backpack-type radiation detector (BRD)

for the detection of illicit trafficking of radioactive material

Instrumentation pour la radioprotection – Détecteur de rayonnement de type

sac à dos (BRD) pour la détection du trafic illicite des matières radioactives

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 13.280 ISBN 978-2-8322-6053-1

– 2 – IEC 62694:2022 © IEC 2022
CONTENTS
FOREWORD . 5
INTRODUCTION . 7
1 Scope . 8
2 Normative references . 8
3 Terms and definitions, abbreviated terms and symbols, quantities and units . 9
3.1 Terms and definitions . 9
3.2 Abbreviated terms and symbols . 10
3.3 Quantities and units . 10
4 General test procedure . 11
4.1 General . 11
4.2 Standard test conditions . 11
4.3 Uncertainties. 11
4.4 Statistical fluctuations . 11
4.5 Background radiation during testing . 12
4.6 Radiation sources . 12
4.7 Special nuclear material (SNM) and depleted uranium (DU) sources . 12
4.8 BRD set up . 12
4.9 Speed of moving sources including scaling of speed and distance . 14
4.10 Functionality tests . 14
4.10.1 General . 14
4.10.2 Pre-test measurements . 15
4.10.3 Intermediate-test measurements . 15
4.10.4 Post-test measurements . 16
4.10.5 Acceptance criteria . 16
5 General requirements . 17
5.1 Design requirements . 17
5.2 Markings . 17
5.3 Switches . 17
5.4 Effective range of dose rate measurement – photons . 17
5.5 Explosive atmospheres . 17
5.6 Power supply . 17
5.6.1 Requirements . 17
5.6.2 Method of test. 17
5.7 Data format . 18
5.7.1 Requirements . 18
5.7.2 Method of test. 18
5.8 Data transfer . 18
5.9 User interface – Indications . 19
5.10 Alarms . 19
5.10.1 Alarm indication . 19
5.10.2 Personal protection alarm . 19
5.10.3 Audible indication for searching . 19
5.10.4 Audible alarms . 19
6 Radiation detection requirements . 19
6.1 False alarm test . 19
6.1.1 Requirements . 19

IEC 62694:2022 © IEC 2022 – 3 –
6.1.2 Method of test. 19
6.2 Alarm response to gamma radiation . 20
6.2.1 Requirements . 20
6.2.2 Method of test. 20
6.3 Alarm response to neutron radiation, if provided . 20
6.3.1 Requirements . 20
6.3.2 Method of test. 20
6.4 Personal radiation protection alarm and response time . 21
6.4.1 Requirements . 21
6.4.2 Method of test. 21
6.5 Gamma-ray ambient dose equivalent rate indication . 21
6.5.1 Requirements . 21
6.5.2 Method of test. 21
6.6 Over range test . 21
6.6.1 Requirements . 21
6.6.2 Method of test. 21
6.7 Neutron indication in the presence of photons, if applicable . 22
6.7.1 Requirements . 22
6.7.2 Method of test. 22
6.8 Detection of gradually increasing radiation levels . 22
6.8.1 Requirements . 22
6.8.2 Method of test. 22
6.9 Radionuclide identification, when provided . 23
6.9.1 Single radionuclide identification . 23
6.9.2 Simultaneous identification . 24
6.9.3 False identification. 25
6.9.4 Over range characteristics for identification . 25
6.10 Addressing natural background variations . 25
6.10.1 Requirements . 25
6.10.2 Method of test. 25
7 Climatic requirements . 26
7.1 General . 26
7.2 Ambient temperature. 26
7.2.1 Requirements . 26
7.2.2 Method of test. 26
7.3 Temperature shock . 26
7.3.1 Requirements . 26
7.3.2 Method of test. 27
7.4 Relative humidity . 27
7.4.1 Requirements . 27
7.4.2 Method of test. 27
7.5 Low/high temperature startup . 27
7.5.1 Requirements . 27
7.5.2 Method of test. 28
7.6 Dust and moisture protection . 28
7.6.1 Requirements . 28
7.6.2 Method of test – Dust . 28
7.6.3 Method of test – Moisture . 28
8 Mechanical requirements . 28

– 4 – IEC 62694:2022 © IEC 2022
8.1 General . 28
8.2 Vibration . 29
8.2.1 Requirements . 29
8.2.2 Method of test. 29
8.3 Microphonics/Impact . 29
8.3.1 Requirements . 29
8.3.2 Method of test. 29
8.4 Mechanical shock . 29
8.4.1 Requirements . 29
8.4.2 Method of test. 29
8.5 Drop . 30
8.5.1 Requirements . 30
8.5.2 Method of test. 30
9 Electromagnetic requirements . 30
9.1 General . 30
9.2 Electrostatic discharge (ESD) . 30
9.2.1 Requirements . 30
9.2.2 Method of test. 30
9.3 Radio frequency (RF) . 30
9.3.1 Requirements . 30
9.3.2 Method of test. 30
9.4 Radiated RF emissions . 31
9.4.1 Requirements . 31
9.4.2 Method of test. 31
9.5 Conducted disturbances. 31
9.5.1 Requirements . 31
9.5.2 Method of test. 31
9.6 Magnetic fields . 31
9.6.1 Requirements . 31
9.6.2 Method of test. 31
10 Documentation . 32
10.1 Operation and maintenance manual . 32
10.2 Test certificate . 32
10.3 Declaration of conformity . 32
Annex A (informative) Summary of fluence rate calculations . 33
Bibliography . 35

Figure 1 – Diagram of the BRD testing angles and source movement directions . 13
Figure 2 – Diagram of the BRD reference point . 14

Table 1 – Standard test conditions . 11
Table 2 – Test results analysis . 17
Table 3 – List of radionuclides for identification tests . 23
Table 4 – Identification acceptance criteria . 24

IEC 62694:2022 © IEC 2022 – 5 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
RADIATION PROTECTION INSTRUMENTATION – BACKPACK-TYPE
RADIATION DETECTOR (BRD) FOR THE DETECTION OF ILLICIT
TRAFFICKING OF RADIOACTIVE MATERIAL

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote international
co-operation on all questions concerning standardization in the electrical and electronic fields. To this end and
in addition to other activities, IEC publishes International Standards, Technical Specifications, Technical Reports,
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preparation is entrusted to technical committees; any IEC National Committee interested in the subject dealt with
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with the IEC also participate in this preparation. IEC collaborates closely with the International Organization for
Standardization (ISO) in accordance with conditions determined by agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
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Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence between
any IEC Publication and the corresponding national or regional publication shall be clearly indicated in the latter.
5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
services carried out by independent certification bodies.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of patent
rights. IEC shall not be held responsible for identifying any or all such patent rights.
IEC 62694 has been prepared by subcommittee 45B: Radiation protection instrumentation, of
IEC technical committee 45: Nuclear instrumentation. It is an International Standard.
This second edition cancels and replaces the first edition, published in 2014. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) making the standard consistent with the new standards for detection of illicit trafficking of
radioactive material;
b) creating unformed functionality test for all environmental, electromagnetic and mechanical
tests and a requirement for the coefficient of variation of each nominal mean reading;
c) revised radiological requirements including the simplification of radionuclide identification
acceptance criteria;
d) reference to IEC 62706 for the environmental, electromagnetic and mechanical test
conditions.
– 6 – IEC 62694:2022 © IEC 2022
The text of this International Standard is based on the following documents:
Draft Report on voting
45B/1012/FDIS 45B/1018/RVD
Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this International Standard is English.
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
described in greater detail at www.iec.ch/publications.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under webstore.iec.ch in the data related to the
specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
IMPORTANT – The "colour inside" logo on the cover page of this document indicates that it
contains colours which are considered to be useful for the correct understanding of its
contents. Users should therefore print this document using a colour printer.

IEC 62694:2022 © IEC 2022 – 7 –
INTRODUCTION
Radioactive sources out of regulatory control, so-called “orphan sources”, have frequently
caused serious radiation exposures and widespread contamination. Although illicit trafficking in
nuclear and other radioactive materials is not a new phenomenon, concern about a nuclear
“black market” has increased particularly in view of its terrorist potential.
In response to the technical policy of agencies such as the International Atomic Energy Agency
(IAEA), the World Customs Organization (WCO) and the International Criminal Police
Organization (Interpol) related to the detection and identification of special nuclear materials
and security trends, nuclear instrumentation companies are developing and manufacturing
radiation instrumentation to assist in the detection of illicit movement of radioactive and special
nuclear materials. This type of instrumentation is widely used for security purposes at nuclear
facilities, border control checkpoints, international seaports, airports, and major events.
To ensure that measurement results made at different locations are consistent it is imperative
that radiation instrumentation be designed to specifications based upon agreed performance
requirements. IEC standards have been developed to establish performance requirements for
personal radiation detectors, radiation portal monitors, highly sensitive gamma and neutron
detection systems, spectrometric personal radiation detectors, vehicle mounted mobile
systems, and backpack-based radiation detection and identification systems. A list of those
standards is given below.
Type of IEC
Title of the standard
instrumentation number
Radiation protection instrumentation – Alarming Personal Radiation Devices
(PRDs) for the detection of illicit trafficking of radioactive material
Radiation protection instrumentation – Spectroscopy-Based Alarming Personal
Body-worn 62618 Radiation Devices (SPRDs) for the detection of illicit trafficking of radioactive
material
Radiation protection instrumentation – Backpack-type radiation detector (BRD) for
the detection of illicit trafficking of radioactive material
Radiation protection instrumentation – Hand-held instruments for the detection and
62327 identification of radionuclides and for the estimation of ambient dose equivalent
rate from photon radiation
Portable or hand-
Radiation protection instrumentation – Highly sensitive hand-held instruments for
held 62533
photon detection of radioactive material
Radiation protection instrumentation – Highly sensitive hand-held instruments for
neutron detection of radioactive material
Radiation protection instrumentation – Installed radiation portal monitors (RPMs)
for the detection of illicit trafficking of radioactive and nuclear materials
Portal
Radiation protection instrumentation – Spectrometric radiation portal monitors
62484 (SRPMs) used for the detection and identification of illicit trafficking of radioactive
material
Radiation protection instrumentation – Data format for radiation instruments used
Data format 62755
in the detection of illicit trafficking of radioactive materials
Radiation protection instrumentation – Vehicle-mounted mobile systems for the
Mobile system 63121
detection of illicit trafficking of radioactive materials

– 8 – IEC 62694:2022 © IEC 2022
RADIATION PROTECTION INSTRUMENTATION – BACKPACK-TYPE
RADIATION DETECTOR (BRD) FOR THE DETECTION OF ILLICIT
TRAFFICKING OF RADIOACTIVE MATERIAL

1 Scope
This document applies to backpack-type radiation detectors (BRDs) that are primarily used for
the detection of illicit trafficking of radioactive material. BRDs are portable instruments designed
to be worn during use. BRDs detect gamma radiation and may include neutron detection and
the ability to identify gamma-ray emitting radionuclides.
This document establishes the operational and testing requirements associated with radiation
measurements and the expected electrical, mechanical, and environmental conditions while in
use.
This document does not apply to ambient or personal dose equivalent rate meters which are
covered in IEC 60846-1 or IEC 61526, respectively.
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.
IEC 60050-395:2014, International Electrotechnical Vocabulary (IEV) – Part 395: Nuclear
instrumentation – Physical phenomena, basic concepts, instruments, systems, equipment and
detectors
IEC60050-395:2014/AMD1:2016
IEC 60050-395:2014/AMD2:2020
IEC 60068-2-11, Environmental testing – Part 2-11: Tests – Test Ka: Salt mist
IEC 60079-11, Explosive atmospheres – Part 11: Equipment protection by intrinsic safety "i"
IEC 62706, Radiation protection instrumentation – Recommended climatic, electromagnetic and
mechanical performance requirements and methods of tests
IEC 62755, Radiation protection instrumentation – Data format for radiation instruments used
in the detection of illicit trafficking of radioactive materials
UL 913, Standard for Intrinsically Safe Apparatus and Associated Apparatus for Use in Class I,
II, III, Division 1, Hazardous (Classified) Locations

IEC 62694:2022 © IEC 2022 – 9 –
3 Terms and definitions, abbreviated terms and symbols, quantities and units
3.1 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 60050-395, as well
as the following apply.
ISO and IEC maintain terminological databases for use in standardization at the following
addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
3.1.1
alarm
audible, visible, or other signal activated when the instrument reading exceeds a pre-set value,
falls outside of a pre-set range, or when the instrument detects the presence of the source of
radiation according to a pre-set condition
3.1.2
background level
radiation field in which there are no external radioactive sources present other than those in
the natural background at the location of the measurements
3.1.3
backpack-type radiation detector
instrument composed of several radiation detection components that are placed inside a
backpack or other similar enclosure with an external user interface or control device
3.1.4
coefficient of variation
COV
ratio of the standard deviation s to the arithmetic mean 𝑥𝑥̅ of a set of n measurements x given by
i
the following formula:
𝑛𝑛
𝑠𝑠 1 1
𝑉𝑉 = = � �(𝑥𝑥 −𝑥𝑥̅)
𝑖𝑖
𝑥𝑥̅𝑥𝑥̅𝑛𝑛− 1
3.1.5
fluence
Φ
quotient of dN by da, where dN is the number of particles incident on a sphere of cross-sectional
area da: Φ = dN/da
3.1.6
fluence rate
𝜙𝜙̇
𝑑𝑑𝑑𝑑
quotient of dΦ by dt, where dΦ is the increment of the fluence in the time interval dt, thus 𝜙𝜙̇=
𝑑𝑑𝑑𝑑
-2 -1
Note 1 to entry: The unit of fluence rate is m • s .
3.1.7
type test
conformity test made on one or more items representative of the production

– 10 – IEC 62694:2022 © IEC 2022
3.1.8
user interface
software and/or hardware that manages interactions between a user and equipment
3.1.9
variance
σ
measure of dispersion, which is the sum of the squared deviation of observations from their
mean divided by one less than the number of observations
n
2 2
σ = (x x)
∑
i
n−1
i=1
3.2 Abbreviated terms and symbols
BRD backpack-type radiation detector
COV coefficient of variation
cps counts per second
DU depleted uranium
ESD electrostatic discharge
GPS global positioning system
HDPE high-density polyethylene
HEU highly-enriched uranium
HPGe high purity germanium
ICRU International commission on radiation units and measurements
NORM naturally occurring radioactive material
PMMA polymethyl methacrylate
r radius
RF radio frequency
SNM special nuclear material
WGPu weapons-grade plutonium
XML eXtensible Markup Language
3.3 Quantities and units
In this document, units of the International System (SI) are used . The definitions of radiation
quantities are given in IEC 60050-395.
The following units may also be used:
-19
• for energy: electron-volt (symbol: eV), 1 eV = 1,602 × 10 J;
• for time: years (symbol: y), days (symbol: d), hours (symbol: h), minutes (symbol: min);
• for temperature: degrees Celsius (symbol: °C), 0 °C = 273,15 K.
Multiples and submultiples of SI units are used, when practicable, according to the SI system.
___________
1 th
International Bureau of Weights and Measures: The International System of Units, 8 edition, 2006.

IEC 62694:2022 © IEC 2022 – 11 –
4 General test procedure
4.1 General
Unless otherwise specified in an individual step, tests enumerated in this document may be
used as part of a type test or an acceptance test.
4.2 Standard test conditions
Except where otherwise specified, the tests described in this document should be performed
under the standard test conditions given in Table 1. The ambient temperature, relative humidity,
and atmospheric pressure shall be recorded during testing.
Table 1 – Standard test conditions
Influence quantity Standard test conditions
Ambient temperature 18 °C to 25 °C
Relative humidity ≤ 75 %
Atmospheric pressure 70 kPa to 103,3 kPa
-1
Ambient dose equivalent rate less than or equal to 0,15 μSv•h
Gamma radiation background
Natural conditions without the presence of man-made emitters
Natural conditions without the presence of man-made emitters
Neutron background
Neutron sources at levels that could affect the performance of a test shall not be
in the test area
NOTE BRDs are typically used in non-radiological areas, e.g., shipping ports and border locations. Man-made
radiological materials such as radiation sources are not expected to be present in these areas. Open indoor spaces
are expected to be used when performing most of the tests described in this document.
4.3 Uncertainties
Unless otherwise stated for a specific quantity, the uncertainties for any measurable quantity
(e.g., radiation field) should not exceed ±15 % with a coverage factor of k = 1, except for
background radiation measurements that may exceed this value.
4.4 Statistical fluctuations
For tests involving the use of radioactive sources to verify susceptibility to a climatic,
electromagnetic, or mechanical condition (Clauses 7, 8, and 9), the radiation field produced by
the sources to verify a BRD’s response shall be adjusted to reduce the magnitude of the
statistical fluctuations.
If the magnitude of the statistical fluctuations arising from the random nature of radiation alone
is a significant fraction of the variation of the indication permitted in the test (i.e., fluctuations
greater than 12 %), then the radiation field should be increased to reduce the fluctuation of the
readings. See NIST Technical Note 2073 for additional guidance (see Bibliography). The COV
for the nominal mean reading shall be less than or equal to 12 % for measurements with
sources.
For measurements without sources (i.e., at the level of background radiation), the BRD is
observed in order to verify that alarms and spurious indications are not produced by an influence
quantity (e.g., temperature, humidity, RF, impact, vibration). Readings are expected to have
large fluctuations (COV > 12 %).

– 12 – IEC 62694:2022 © IEC 2022
The bibliography contains a list of several publications for additional information regarding
statistical processes associated with radiation measurement.
4.5 Background radiation during testing
Testing shall be performed in a controlled area having a radiation background as defined in
Table 1.
4.6 Radiation sources
241 137 60
For alarm tests, Am, Cs, and Co are used to provide a fluence rate of
-1 -2
4 photons•s •cm (-0 %, +5 %) at the reference point of the BRD. The fluence rate shall be
determined for the gamma-ray energies listed in Table 3. The ambient dose equivalent rate
shall be determined using a photon cut-off energy of 40 keV. Annex A provides information for
determination of fluence rate.
-1 -2
For identification tests, a fluence rate of 1,5 photons•s •cm (-0 %, +5 %) at the reference
137 60 67 131 99m
point of the BRD shall be emitted from DU, HEU, WGPu, Cs, Co, Ga, I, Tc, and
201 99m 67 131 201
Tl. The medical radionuclides ( Tc, Ga, I, and Tl) shall be surrounded by 8 cm of
polymethyl methacrylate (PMMA) for test purposes to represent in-vivo conditions, for these
sources the fluence rate is measured outside the PMMA. The fluence rate shall be determined
for the gamma-ray energies listed in Table 3.
252 244 248
Cf or Cm or Cm is the reference source for neutron alarm testing. The source shall
-1
have a neutron emission rate of 20 000 s (-10 %, +40 %) and, unless otherwise stated, be
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surrounded by high-density polyethylene (HDPE) moderator (density between 0,93 g•cm and
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0,97 g•cm ). The HDPE moderator can be spherical or cylindrical and shall have a wall
thickness of 4 cm on all sides and an inner cavity not larger than 3 cm in diameter and length.
The source shall be positioned at the centre of the cavity.
NOTE Additional information about neutron radiation fields can be found in ISO 8529-1:2021. Additional information
can be found in R. Radev et al. in Bibliography.
Sources used for testing shall be checked for gamma-ray emitting impurities using a high purity
germanium detector (HPGe). The spectra shall be recorded. Identification of impurities is
acceptable.
4.7 Special nuclear material (SNM) and depleted uranium (DU) sources
For SNM and DU sources, different masses,
...