IEC 62463:2024

IEC 62463 ®
Edition 2.0 2024-07
INTERNATIONAL
STANDARD
colour
inside
Radiation protection instrumentation – X-ray systems for the security screening
of persons
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form
or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from
either IEC or IEC's member National Committee in the country of the requester. If you have any questions about IEC
copyright or have an enquiry about obtaining additional rights to this publication, please contact the address below or
your local IEC member National Committee for further information.

IEC Secretariat Tel.: +41 22 919 02 11
3, rue de Varembé info@iec.ch
CH-1211 Geneva 20 www.iec.ch
Switzerland
About the IEC
The International Electrotechnical Commission (IEC) is the leading global organization that prepares and publishes
International Standards for all electrical, electronic and related technologies.

About IEC publications
The technical content of IEC publications is kept under constant review by the IEC. Please make sure that you have the
latest edition, a corrigendum or an amendment might have been published.

IEC publications search - webstore.iec.ch/advsearchform IEC Products & Services Portal - products.iec.ch
The advanced search enables to find IEC publications by a Discover our powerful search engine and read freely all the
variety of criteria (reference number, text, technical publications previews, graphical symbols and the glossary.
committee, …). It also gives information on projects, replaced With a subscription you will always have access to up to date
and withdrawn publications. content tailored to your needs.

IEC Just Published - webstore.iec.ch/justpublished
Electropedia - www.electropedia.org
Stay up to date on all new IEC publications. Just Published
The world's leading online dictionary on electrotechnology,
details all new publications released. Available online and once
containing more than 22 500 terminological entries in English
a month by email.
and French, with equivalent terms in 25 additional languages.

Also known as the International Electrotechnical Vocabulary
IEC Customer Service Centre - webstore.iec.ch/csc
(IEV) online.
If you wish to give us your feedback on this publication or need

further assistance, please contact the Customer Service
Centre: sales@iec.ch.
IEC 62463 ®
Edition 2.0 2024-07
INTERNATIONAL
STANDARD
colour
inside
Radiation protection instrumentation – X-ray systems for the security screening
of persons
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 13.280 ISBN 978-2-8322-9377-5
– 2 – IEC 62463:2024 © IEC 2024
CONTENTS
FOREWORD . 4
INTRODUCTION . 6
1 Scope . 7
2 Normative references . 7
3 Terms and definitions . 8
4 Units . 11
5 General test procedures . 11
5.1 Nature of tests . 11
5.2 Reference conditions and standard test conditions . 11
5.3 Tests performed under standard test conditions . 12
5.4 Tests performed with variation of influence quantities . 12
6 Safety considerations . 13
6.1 General . 13
6.2 Shielding . 13
6.2.1 Requirements . 13
6.2.2 Method of test. 13
6.3 System controls and normal operation indications . 13
6.3.1 Requirements . 13
6.3.2 Method of test. 14
6.4 Safety indicators and interlocks . 14
6.4.1 Safety standards. 14
6.4.2 Requirements . 14
6.4.3 Method of test. 14
7 Conditions and methods for producing the X-ray screening spectra . 15
7.1 General . 15
7.2 Tube potential characteristics of the X-ray unit. 15
7.2.1 Requirements . 15
7.2.2 Method of test. 15
8 Effective dose at the position of the person being screened . 15
8.1 Classification of systems . 15
8.2 Requirements . 15
8.2.1 General . 15
8.2.2 General-use systems . 16
8.2.3 Limited-use systems . 16
8.3 Method of test . 16
9 Electrical characteristics . 16
9.1 Requirements . 16
9.2 Method of test . 16
10 Environmental conditions . 17
10.1 Ambient temperature. 17
10.1.1 Requirements . 17
10.1.2 Method of test. 17
10.2 Relative humidity . 17
10.2.1 Requirements . 17
10.2.2 Method of test. 17
11 Electromagnetic compatibility . 17

11.1 Requirements . 17
11.2 Method of test . 18
12 Mechanical characteristics . 18
12.1 Requirements . 18
12.2 Method of test . 18
13 Documentation . 18
13.1 Standard operating procedure . 18
13.2 Other documentation. 19
Annex A (normative) Estimation of the effective dose per screening at the reference
position . 20
A.1 General . 20
A.2 Determination of the reference position . 20
A.3 Measurement of the air kerma at the reference position . 21
A.4 Estimation of the half-value layer of aluminum of the beam . 21
A.5 Estimation of the effective dose . 21
Annex B (informative) Guidance on detector choice for measuring air kerma . 24
B.1 Background. 24
B.2 Guidance . 25
Annex C (informative) Requirements of International Basic Safety Standards (BSS) for
Protection Against Ionizing Radiation and For the Safety of Radiation Sources.
International Atomic Energy Agency (IAEA) Safety Series No. 115, 1996 . 26
Bibliography . 27

Figure A.1 – Illustrative examples . 20
Figure A.2 – Conversion coefficients from air kerma to effective dose from Table A.1

plotted as a function of HVL . 23
Al
Table 1 – Reference conditions and standard test conditions . 11
Table 2 – Tests performed under standard test conditions . 12
Table 3 – Tests performed with variations of influence quantities . 12
Table A.1 – Conversion coefficients from air kerma to operational quantities for
estimating effective dose . 22

– 4 – IEC 62463:2024 © IEC 2024
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
RADIATION PROTECTION INSTRUMENTATION –
X-RAY SYSTEMS FOR THE SECURITY SCREENING OF PERSONS

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,
Publicly Available Specifications (PAS) and Guides (hereafter referred to as "IEC Publication(s)"). Their
preparation is entrusted to technical committees; any IEC National Committee interested in the subject dealt with
may participate in this preparatory work. International, governmental and non-governmental organizations liaising
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
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
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) IEC draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). IEC takes no position concerning the evidence, validity or applicability of any claimed patent rights in
respect thereof. As of the date of publication of this document, IEC had not received notice of (a) patent(s), which
may be required to implement this document. However, implementers are cautioned that this may not represent
the latest information, which may be obtained from the patent database available at https://patents.iec.ch. IEC
shall not be held responsible for identifying any or all such patent rights.
IEC 62463 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 2010. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) title modified;
b) the main dose quantity was updated from ambient dose equivalent (H*(10)) to the
operational quantities recommended in ICRU Report 95:2020;
c) the scope has been updated from X-ray systems for screening persons to X-ray systems
that deliberately expose persons to X-rays for security purposes, which clarifies the
ambiguity of whether occupied vehicle scanners are within scope;

d) the scheme for classifying systems was changed from one based on whether the system is
backscatter, transmission or a combination to a classification system based on the dose
level and administrative controls;
e) numerous electrical, environmental, electromagnetic, and mechanical safety requirements
were updated.
The text of this International Standard is based on the following documents:
Draft Report on voting
45B/1058/FDIS 45B/1068/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, or
• revised.
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.

– 6 – IEC 62463:2024 © IEC 2024
INTRODUCTION
This document concerns the radiation safety of security screening systems where persons are
intentionally exposed to X-rays. The document is applicable to a wide range of system designs,
X-ray spectra, and irradiation geometries, and while current screening systems can be divided
into X-ray backscatter, X-ray transmission, and combination systems, the methods in the
document are general enough to be applicable to other systems too. The document sets dose
limits in terms of effective dose and uses the operational quantities described in ICRU Report 95
to estimate the effective dose per screening. The document also specifies other requirements
related to the electrical, environmental, electromagnetic, and mechanical safety of the systems.

RADIATION PROTECTION INSTRUMENTATION –
X-RAY SYSTEMS FOR THE SECURITY SCREENING OF PERSONS

1 Scope
This document is applicable to security screening systems designed to expose persons to
X-rays. In particular, the document applies to systems where the body is exposed to the primary
beam of X-rays. It is common to divide currently used systems into three types: backscatter
systems, transmission systems and combination backscatter/transmission systems. Some
examples of systems that fall within the scope of this document are backscatter X-ray scanners;
transmission X-ray scanners; occupied vehicle scanners.
The purpose of this document is to provide standardized requirements and test methods to
ensure the safe operation of X-ray personnel screening systems, from a radiation protection
point of view. In particular, the document specifies requirements related to the radiation
protection of the persons being screened, persons who are in the vicinity of the equipment and
the operators. Standard methods are provided to estimate the effective dose to the persons
being screened. There are several simplifying assumptions inherent in such procedures that
limit their accuracy. Nevertheless, there is value in having simple standard methods for dose
estimation, e.g. for regulatory use. When highly accurate dose estimates are needed, different
methods should be used that account for the particular characteristics of the X-ray system and
persons being screened.
The document does not address image quality or detection performance.
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 60721-3-3:2019, Classification of environmental conditions – Part 3-3: Classification of
groups of environmental parameters and their severities – Stationary use at weatherprotected
locations
IEC 61187:1993, Electrical and electronic equipment – Documentation
IEC 61326-1:2020, Electrical equipment for measurement, control and laboratory use – EMC
requirements – Part 1: General requirements
IEC 61508 (all parts), Functional safety of electrical/electronic/programmable electronic safety
related systems
IEC 62061:2021, Safety of machinery – Functional safety of safety-related control systems
ISO 4037-1:2019, Radiological protection – X and gamma reference radiation for calibrating
dosemeters and doserate meters and for determining their response as a function of photon
energy – Part 1: Radiation characteristics and production methods
ISO 13849-1:2023, Safety of machinery – Safety-related parts of control systems – Part 1:
General principles for design
– 8 – IEC 62463:2024 © IEC 2024
ICRU Report 95:2020, Operational Quantities for External Radiation Exposure
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminology databases for use in standardization at the following
addresses:
• IEC Electropedia: available at https://www.electropedia.org/
• ISO Online browsing platform: available at https://www.iso.org/obp
NOTE The general terminology concerning X-ray screening systems is given in IEC 60050-395:2014.
3.1
ambient dose
H*
ambient dose at a point in a radiation field is defined as:
**
H Kh×
E
max
where
K is the air kerma at the point, and
*
h is a conversion coefficient relating air kerma to the maximum value of effective dose,
E
max
E , for various irradiation conditions
max
Note 1 to entry: See ICRU Report 95 for more details. H* corresponds to the maximum effective dose that could be
received by a person if they were uniformly irradiated by an equivalent field of radiation. More specifically, it is the
maximum effective dose as calculated by exposure of the whole-body ICRP/ICRU adult reference phantoms (ICRP,
2009) for broad uniform parallel beams of the radiation field incident in irradiation geometries antero-posterior (AP),
posterior-anterior (PA), left lateral (LLAT), right lateral (RLAT), rotational (ROT), isotropic (ISO), superior hemisphere
semi-isotropic (SS-ISO), and inferior hemisphere semi-isotropic (IS-ISO).
3.2
constant potential X-ray unit
unit in which the ripple of the high voltage does not exceed ±10 %
3.3
effective dose
dose quantity intended to reflect the whole body stochastic health risk due to radiation exposure
(see ICRP Report 103)
Note 1 to entry: It is calculated based on the sum of the equivalent doses in various organs multiplied by the
appropriate tissue weighting factors.
3.4
general-use system
X-ray screening system that is configured to deliver an effective dose of less than 0,25 µSv per
screening (using the dose estimation methods defined in this document) and operating using
the administrative controls specified in this document. Given proper justification and certain
restrictions, general-use systems may be operated without specific controls that would limit the
number of individuals scanned or the number of scans per individual in a year
Note 1 to entry: This definition was reproduced, with the permission of the Health Physics Society (HPS), from
ANSI/HPS N43.17-2009 (R2018)
=
3.5
half value layer
HVL
HVLx
thickness of the specified material which attenuates the X-ray beam so that the air kerma rate
is reduced to one half of its original value
Note 1 to entry: The measurement should be made in narrow-beam geometry, meaning the contribution of all
scattered radiation, other than any which might initially be present in the beam, is excluded.
3.6
filtration
total filtration is made up of the fixed filtration and any additional filtration used by the
manufacturer. The fixed filtration comprises the inherent filtration of the tube, plus that due to
the monitor ionisation chamber
Note 1 to entry: The inherent filtration of the tube is due to the various constituent elements (glass of the bulb, oil,
window, etc.) and is expressed, for a given high voltage, as the thickness of an aluminium filter which, in the absence
of the constituent elements of the tube, would supply a radiation having the same first HVL.
3.7
limited-use system
personnel screening system that is configured to deliver an effective dose of less than 10 μSv
per screening (using the dose estimation methods defined in this standard) and which does not
meet the definition of a general-use system. Limited-use systems require additional controls
and documentation to ensure that annual individual dose limits are not exceeded
Note 1 to entry: This definition was reproduced, with the permission of the Health Physics Society (HPS), from
ANSI/HPS N43.17.
3.8
occupied zone
volume in which a person could be exposed to the primary X-ray beam while the SOP is being
followed. This volume uses the same frame of reference as a person being scanned
3.9
operator
person that controls one or more aspects of the screening procedure. An operator is authorized
to perform their duties, appropriately trained, and performs their duties according to the SOP
3.10
personal dose
H
p
personal dose at a point in a radiation field is defined as:
H Kh×
pp
where
K is the air kerma at the point, and
h is a conversion coefficient relating air kerma to the personal dose, H , that is appropriate
p p
for the spectrum and irradiation geometry
Note 1 to entry: See ICRU Report 95 for more details.
3.11
primary beam
consists of X-rays that have exited the beam-defining aperture but have not been absorbed or
scattered
=
– 10 – IEC 62463:2024 © IEC 2024
3.12
reference instrument
instrument whose calibration is traceable either directly or indirectly to primary standards held
by a national primary laboratory or to an acknowledged reference laboratory which holds
appropriate standards
3.13
reference position
location within the occupied zone that receives the greatest dose per screening. The reference
position uses the same frame of reference as the person, which may be moving relative to the
X-ray source in some cases
3.14
restricted zone
volume surrounding the X-ray system where access for the general public is restricted during
operation of the scanner
3.15
safety interlocks
devices which are intended to prevent or interrupt the generation of X-radiation whenever safety
is compromised by access to the interior of the system, operational irregularity or equipment
failure
3.16
scanning system
system
whole equipment used to produce a scan, including the X-ray generator and collimator
3.17
screening procedure
procedure, described in the SOP, that is followed to completely inspect something using the
X-ray system
Note 1 to entry: Depending on the concept of operation of the system, this could involve taking multiple scans.
3.18
standard operating procedure
SOP
document developed by the facility that describes the processes for performing screenings
using the X-ray system
3.19
ripple
ratio, expressed as a percentage, defined for a given current by the Formula:
(UU– )×100 / U
max min max
where
U is the maximum value, and
max
U is the minimum value of the voltage.
min
3.20
X-ray unit
assembly comprising a high voltage supply, an X-ray tube with its protective housing, and high
voltage electrical connections

3.21
X-ray tube
vacuum tube designed to produce X-rays by bombardment of the anode by a beam of electrons
accelerated through a potential difference
4 Units
In this document, the units are the multiples and sub-multiples of units of the International
System of Units (SI) . The following non-SI units are also used:
Time: years, days, hours (h), minutes (min).
–19
For energy: electron-volt (eV), (1 eV = 1,602 × 10 J).
NOTE Definitions of the radiation quantities and dosimetric terms are given in IEC 60050-395.
5 General test procedures
5.1 Nature of tests
Unless otherwise specified in the individual subclauses, all tests enumerated in this document
are to be considered as type tests.
5.2 Reference conditions and standard test conditions
Reference and standard test conditions are given in Table 1. Reference conditions are those
conditions to which the performance of the instrument is referred, and standard test conditions
indicate the necessary tolerances in practical testing. Except where otherwise specified, the
tests in this document shall be performed under the standard test conditions given in the third
column of Table 1.
Table 1 – Reference conditions and standard test conditions
Reference conditions Standard test conditions
Influence quantities
(unless otherwise indicated (unless otherwise indicated by the
by the manufacturer) manufacturer)
Warm-up time 15 min > 15 min
Ambient temperature 20 °C 18 °C to 22 °C
Relative humidity 65 % 50 % to 75 %
Atmospheric pressure 101,3 kPa 70 kPa to 106 kPa
Power supply voltage Nominal power supply voltage Nominal power supply voltage ±1 %
Power supply frequency Nominal frequency Nominal frequency ±1 %
Power supply waveform Sinusoidal Sinusoidal with total harmonic distortion lower
than 5 %
–1 –1
Gamma radiation
Air kerma rate 0,1 µGy⋅h Less than air kerma rate of 0,25 µGy⋅h
background
Electromagnetic field of Less than the lowest value that causes
Negligible
external origin interference
Magnetic induction of Negligible Less than twice the value of the induction due
external origin to earth's magnetic field
Equipment controls Set up for normal operation Set up for normal operation

___________
1 th
(SI International Bureau of Weights and Measures: The International System of Units, 8 edition 2006).

– 12 – IEC 62463:2024 © IEC 2024
5.3 Tests performed under standard test conditions
Table 2 lists the tests to be performed under standard test conditions and gives references to
the sections describing applicable requirements and test methods.
Table 2 – Tests performed under standard test conditions
Characteristics under test Requirements (subclause) Method of test (subclause)
Effective dose to person being scanned 8.2 8.3

5.4 Tests performed with variation of influence quantities
For those tests intended to determine the effects of variations in the influence quantities given
in Table 3, all other influence quantities shall be maintained within the limits for the standard
test conditions given in Table 3, unless otherwise specified in the test procedure concerned.
Table 3 – Tests performed with variations of influence quantities
Characteristic under
Range of values of Limits of variation of indications Method of tests
test or influence
influence quantities or of the reference air kerma (subclause)
quantity
Mains operation From –10 % to +10 % of 10 % 9.2
nominal power supply
Voltage
From 47 Hz to 51 Hz or
57 Hz to 61 Hz
Temperature From 5 °C to +40 °C Operation to remain satisfactory. 10.1.2
Air kerma change less than 10 %
Relative humidity From 40 % to 93 % at Operation to remain satisfactory. 10.2.2
35 °C Air kerma change less than 10 %
Susceptibility to IEC 61326-1 No change in operational status. No 11.2
electromagnetic fields alarms or other outputs should be
activated when the assembly is
exposed to the field. Air kerma
change less than 10 %
Conducted RF IEC 61326-1 No change in operational status. No 11.2
alarms or other outputs should be
activated when the assembly is
exposed to the field. Air kerma
change less than 10 %
Surges and ring waves IEC 61326-1 No change in operational status. No 11.2
alarms or other outputs should be
activated. Air kerma change less
than 10 %.
Electrostatic discharge IEC 61326-1 No alarms or other outputs should 11.2
be activated when the monitor is
exposed to the discharge. Air
kerma change less than 10 %
Vibration class 3M11, Operation to remain satisfactory 12.2
IEC 60721-3-3:2019
6 Safety considerations
6.1 General
The manufacturer shall provide a description of the radiation safety systems that are designed
to prevent, during normal operation of the X-ray screening system, accidental exposure to the
operator and public and for ensuring that the person being screened is not exposed above
manufacturers stated maximum dose per screening procedure. The accompanying manual
provided by the manufacturer shall include details of the fail-safe features of the radiation safety
exposure circuit. These details shall also include functional test instructions.
The manufacturer shall reference the radiological and electrical safety considerations used for
the system by quoting applicable IEC and ISO publications, see 6.4.1.
6.2 Shielding
6.2.1 Requirements
The ambient dose or ambient dose equivalent shall only exceed 1 µSv in any one hour in the
occupied zone and the restricted zone. National regulations may stipulate lower dose limits and
additional rules may apply (see Annex C, for example). A spatial map shall be produced that
indicates regions where the ambient dose or ambient dose equivalent will not exceed 1 µSv in
any one hour. This map could take the form of a detailed isodose curve or a simpler map that
indicates a rectangular region where the ambient dose or ambient dose equivalent may exceed
1 µSv in any one hour.
6.2.2 Method of test
Determine the region surrounding the scanner where the average ambient dose or ambient
dose equivalent may exceed 1 µSv in any one hour. Careful consideration should be given to
control stations, fissures around doors, ventilation openings, shielding joints and any other
vulnerable areas based on technical drawings. If there are outer doors or removable panels that
are not locked or interlocked, repeat the radiation survey with the doors open and panels
removed. Operate the X-ray scanner in the mode and using any settings (e.g., tube voltage,
current and filtration) that produce the highest dose.
Perform the test with a scatter phantom placed in the occupied zone at a location where a
scanned individual is typically located. Ensure that the scatter phantom weighs 70 kg ± 15 kg
and is composed of some combination of water, polyethylene or alternative material that is
tissue equivalent for the radiation field of interest. Ensure the center of mass of the phantom is
above 50 cm from the floor of the scanner. An example implementation could be constructed
using a polyethylene pipe filled with water (25 cm diameter and 150 cm high).
Estimate the average dose in any one hour by operating the scanner for at least five screening
procedures that repeatedly follow each other as fast as the device is able to perform. Integrate
the dose values over this time and divide by the time necessary to perform the screenings.
Based on such measurements, produce the spatial map described in 6.2.1.
6.3 System controls and normal operation indications
6.3.1 Requirements
The operating conditions, namely the tube voltage and tube current, for each mode of operation
shall be pre-set by the manufacturer and shall not be alterable by the system operator. If there
is more than one mode, prior to each scan a mode indicator shall be clearly visible to the
operator.
– 14 – IEC 62463:2024 © IEC 2024
The operators control panel shall show the following:
– Electrical power to the system is on. Only the operator is permitted to switch on the power
and this should require the use of a key.
– When the X-rays are being produced an "X-rays on" illuminated sign shall operate.
– The voltage and current for the operating mode shall be displayed when required by an
engineer or maintenance staff.
– Indication shall be made for both when the shutter or beam stop is open and/or for when the
scan is taking place, "scan on".
– The production of X-rays shall only start if the illuminated sign "X-rays" is ready to operate.
Sufficient diagnostics shall be designed into the system to facilitate fault finding and to provide
local and remote information on the status of the system. A self-test device shall be provided
to perform self-testing continuously. Operation of the equipment after fault detection shall be
prevented until the fault is cleared. Interlocks, indications and alarms shall be independent of
the system's normal controls and operation indicators.
6.3.2 Method of test
Verify that the operator's control panel displays the information as required in 6.3.1.
Simulate a fault condition and verify that no operation is possible. Examples of simulated fault
conditions include stopping movement of the X-ray beam, stopping movement of a belt,
disabling necessary indicator lights, or opening a chassis door that is required to be locked.
6.4 Safety indicators and interlocks
6.4.1 Safety standards
Appropriate requirements shall apply concerning specification, design, manufacturing,
installation and operation of the equipment, with respect to the necessary hardware and
software.
The manufacturer shall evaluate the system by a risk reduction method. As a result of this they
shall meet IEC 61508 or other international recognized standards providing equivalent
functional safety (e.g., ISO 13849-1 or IEC 62061).
6.4.2 Requirements
Operational interlocks shall terminate the production of X-rays in the event of any operational
problem that could result in abnormal or unintended radiation emission. Either through
redundancy or special design, a malfunction of any operational interlock or any system
monitoring an operational interlock shall also terminate X-ray production regardless of the
actual radiation emission. This shall include but is not limited to: unintended stopping or slowing
of the scanning motion, abnormal or unintended X-ray source output, computer safety system
malfunction, termination malfunction, and when applicable, X-ray shutter or beam stop
mechanism malfunction. For each safety function the risk-reduction method shall specify a
"safety integrity level" (SIL) or "performance level" (PL ), as defined in IEC 62061 and
r
ISO 13849-1, respectively.
6.4.3 Method of test
Switch on the equipment and allow it to run its start-up and possible self-test routines. Simulate
a fault condition in each one of the monitored parameters, verify the operation of the interlocks
and record the warning or fault description.

7 Conditions and methods for producing the X-ray screening spectra
7.1 General
In practice, the X-ray spectrum primarily depends on:
– the high-voltage across the X-ray tube;
– the thickness and nature of the total filtration;
– the type and nature of the target.
7.2 Tube potential characteristics of the X-ray unit
7.2.1 Requirements
The conventionally true value of the potential shall be known to within ±5 %.
7.2.2 Method of test
Estimate the maximum energy present in the X-ray beam. The best methods employ a calibrated
resistor chain or involve the measurement of the maximum photon energy by spectrometry.
Calibrate the measurement equipment at several points close to the stated operating tube
potential. If the estimate is determined by spectrometry, the tube potential shall be found from
the intersection of the extrapolated linear high energy part of the spectrum with the energy axis.
Advice on methods of accomplishing this are described in ISO 4037-1.
8 Effective dose at the position of the person being screened
8.1 Classification of systems
For the purpose of this document, personnel screening systems are divided into two classes
based on their dose and administrative controls: general-use systems and limited use systems.
General-use systems deliver low doses, so individuals can be scanned regularly and still stay
well below applicable annual limits. Such systems therefore require fewer engineering and
administrative controls compared with other X-ray systems. Limited use systems deliver a
higher dose than general-use systems, and require additional administrative controls to ensure
that individuals are not exposed to annual doses that are above applicable limits. Requirements
for the two classes of systems are given in 8.2.
8.2 Requirements
8.2.1 General
The dose and administrative control requirements are different for the different classes of
systems. Lower dose requirements may be specified by national regulations or other applicable
rules.
– 16 – IEC 62463:2024 © IEC 2024
8.2.2 General-use systems
General use systems shall deliver an effective dose of less than 0,25 µSv per screening.
Additionally, the effective dose received by individuals from one facility shall not exceed
250 µSv over a 12-month period . Compliance with this requirement shall be demonstrated by
documenting the routine screening procedures of the facility and typical behavior of the persons
being screened. If individuals are routinely screened more than twice each day by the same
facility, then documentation shall be kept that shows that the effective dose to any one individual
shall not exceed 250 µSv in one year. This can be done, for example, by estimating the
maximum number of times an individual might be scanned and multiplying it by the effective
dose per screening, as estimated using the methods in this document. If such documentation
does not exist for a system, then it shall not be considered a general-use system.
8.2.3 Limited-use systems
Limited-use systems shall deliver an effective dose of less than 10 µSv per screening.
Additionally, such systems shall have administrative controls, in the form of documented
procedures, that ensure that the effective dose to any individual shall be limited to less than
250 µSv in any 12-month period. This shall be accomplished by keeping records to demonstrate
that the effective dose multiplied by the number of screenings to any individual in a 12-month
period does not exceed 250 µSv.
8.3 Method of test
The procedure for estimating the effective dose per screening is given in Annex A. Guidance
on detector choice is given in Annex B. Operate the X-ray system using the procedures in the
SOP. If multiple settings or modes of operation are described in the SOP, then operate the
system using the mode with the highest effective dose per screening. Measure the effective
dose per screening using the methods described in Annex A, based on measurements made at
the reference position using a reference instrument.
9 Electrical characteristics
9.1 Requirements
The system shall be capa
...