IEC 62046:2026

IEC 62046 ®
Edition 2.0 2026-07
INTERNATIONAL
STANDARD
Safety of machinery - Application of protective equipment to detect the presence
of persons
ICS 13.110  ISBN 978-2-8327-1314-3

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CONTENTS
FOREWORD . 6
INTRODUCTION . 8
1 Scope . 10
2 Normative references . 10
3 Terms, definitions and abbreviated terms . 11
3.1 Terms and definitions. 11
3.2 Abbreviated terms . 20
4 General overview. 20
4.1 General . 20
4.2 Selection of active SPE . 23
4.2.1 General . 23
4.2.2 Machine characteristics . 23
4.2.3 User interaction . 24
4.2.4 Environmental characteristics . 24
4.2.5 Characteristics of the hazard zone . 25
4.2.6 Dimensions and characteristics of the human body . 25
4.2.7 Suitability of SPE . 25
4.2.8 Safety integrity characteristics of SPE . 26
4.2.9 Properties and application requirements for specific SPE . 28
4.3 Possibility of defeating . 37
4.4 Positioning of SPE or detection zone(s) . 37
5 Operational functions of sensitive protective devices . 37
5.1 General . 37
5.2 Trip function . 37
5.2.1 General . 37
5.2.2 Determination of the separation distance . 38
5.2.3 Suitability of SPE as a trip device . 41
5.2.4 Additional requirements . 42
5.3 Presence sensing function . 42
5.4 Combination trip and presence sensing function . 43
5.5 Functional testing to detect fault accumulation and undetected faults . 43
6 Optional functions associated with the application of SPE . 43
6.1 General . 43
6.1.1 Overview . 43
6.1.2 Performance monitoring systems . 43
6.1.3 Start interlock . 43
6.1.4 Restart interlock . 44
6.1.5 Muting . 44
6.1.6 Reinitiating of machine operation by the SPE . 44
6.1.7 External device monitoring (EDM) . 44
6.1.8 Automatic selection of active detection zones . 44
6.2 Requirements for optional functions . 45
6.2.1 General . 45
6.2.2 Performance monitoring systems . 45
6.2.3 Start interlock . 45
6.2.4 Restart interlock . 46
6.2.5 Muting . 46
6.2.6 Reinitiating of machine operation by an AOPD . 50
6.2.7 Automatic selection of active detection zones . 52
7 Integration with the safety-related control system . 53
8 Inspection and test . 53
8.1 General . 53
8.2 Functional checks . 53
8.3 Periodic inspection. 54
8.4 Initial inspection and test . 55
8.5 Application-specific tests . 56
9 Information for use . 57
Annex A (informative) Application examples of ESPE . 58
A.1 General . 58
A.2 ESPE used as a trip device . 58
A.3 Use of ESPE to provide a combination trip and presence sensing function. 59
A.3.1 Example 1: Horizontal AOPD with combined trip and presence sensing
function . 59
A.3.2 Example 2: Angled AOPD with combined trip and presence sensing
function . 60
A.3.3 Example 3: Horizontal AOPD . 61
A.3.4 Example 4: Vertical AOPD . 62
A.3.5 Example 5: Vertical AOPD . 63
A.4 Perimeter safeguarding to establish a safeguarded space . 65
Annex B (informative) Additional recommendations for the application of AOPDDRs . 66
B.1 General . 66
B.2 AOPDDR used for the detection of the body or parts of a body with
orthogonal approach . 69
B.2.1 General . 69
B.2.2 Detection of a whole body. 69
B.2.3 Detection of parts of the body . 69
B.3 Examples of the use of an AOPDDR as a whole body trip device . 70
B.4 Examples for the use of an AOPDDR as parts of a body trip device . 72
Annex C (informative) Vision based protective devices using stereo vision techniques
(VBPDST), additional information - Application example of VBPDST . 74
Annex D (informative) Possible approach for the calculation of the separation distance
for SPE using volumetric detection . 76
D.1 General . 76
D.2 Application considerations . 76
D.3 Examples . 76
D.4 Separation distance calculation when H ≥ 900 mm . 80
VT
D.5 Separation distance calculation when H < 900 mm . 81
VT
Annex E (informative) Examples of AOPD muting for applications where whole body
access is possible . 82
E.1 General . 82
E.2 Four muting sensors . 85
E.2.1 Four parallel beam muting sensors – Positioning . 85
E.2.2 Four parallel beam muting sensors – Sequence control . 89
E.2.3 Four parallel beam muting sensors – Timing control . 90
E.2.4 Four parallel beam muting sensors – Connection to a two input muting
control . 91
E.3 Two muting sensors . 92
E.3.1 Two crossed beam muting sensors – Positioning . 92
E.3.2 Two crossed beam muting sensors – Timing control . 95
E.3.3 Two crossed beam muting sensors – Height of the crossing point . 96
E.3.4 Two parallel beam muting sensors – Exit only . 97
E.4 Optional control measures of muting control systems . 100
E.4.1 General . 100
E.4.2 Muting timeout control . 100
E.4.3 Muting enable . 101
E.4.4 Combination of muting enable and muting timeout control . 103
E.4.5 Lateral gap protection . 104
E.5 Example of protection of a conveyor system . 108
Annex F (informative) Automatic switching of active detection zones . 111
F.1 Example of automatic selection of active detection zones . 111
F.2 Examples of automatic selection of active detection zones to allow the
passage of materials into or out of a hazard zone . 112
Annex G (informative) SPE characteristics . 114
G.1 Electro-sensitive protective equipment (ESPE) . 114
G.1.1 Types of ESPE . 114
G.1.2 Active opto-electronic protective devices (AOPD) . 114
G.1.3 Active opto-electronic devices operating by diffuse reflection (AOPDDR) . 115
G.1.4 Vision based protective devices (VBPDs) . 116
G.1.5 Radar-based protective devices (RPD) . 117
G.2 Pressure-sensitive mats and floors . 118
Annex H (informative) Estimation of SIL or PL for muting systems in ESPE
applications . 119
H.1 General . 119
H.2 Preconditions and assumptions for the MS-SB . 120
H.3 Diagnostics . 120
H.4 Safety structure . 121
H.4.1 2-sensors MS-SB . 121
H.4.2 4-Sensors MS-SB . 121
H.5 Calculation examples . 122
H.5.1 Example according to ISO 13849-1 . 122
H.5.2 Example according to IEC 62061 . 123
H.6 Common cause failures. 126
Bibliography . 127

Figure 1 – Relationship of this document to other standards . 9
Figure 2 – Risk reduction process . 22
Figure 3 – Example of the effect of reflective surfaces . 28
Figure 4 – Detection capability of single light beam device . 30
Figure 5 – Detection capability of a multiple light beam device . 30
Figure 6 – Example of use of blanking . 32
Figure 7 – Example of reduced resolution . 33
Figure 8 – Person walking through a two-dimensional detection zone . 40
Figure 9 – Person walking through a horizontal or three-dimensional detection zone . 41
Figure A.1 – ESPE used as a trip device . 58
Figure A.2 – AOPD used to provide combination trip and presence sensing function –
Example 1 . 59
Figure A.3 – AOPD used to provide a combination trip and presence sensing function –
Example 2 . 60
Figure A.4 – Horizontal AOPD – Example 3 . 61
Figure A.5 – Vertical AOPD – Example 4 . 62
Figure A.6 – Increased separation distance – Example 5 . 63
Figure A.7 – Additional guards . 64
Figure A.8 – Use of a trip device . 65
Figure B.1 – Detection zone of an AOPDDR-2D . 67
Figure B.2 – Detection zone of an AOPDDR-3D . 68
Figure B.3 – Use of an AOPDDR as a whole body trip device – Example 1 . 70
Figure B.4 – Use of an AOPDDR as a whole body trip device – Example 2 . 71
Figure B.5 – Use of an AOPDDR as parts of a body trip device – Example 3 . 72
Figure B.6 – Use of an AOPDDR as parts of a body trip device – Example 4 . 72
Figure C.1 – Application example of a VBPDST . 75
Figure D.1 – Approach when H ≥ 900 mm (orthogonal) . 77
VT
Figure D.2 – Approach when H < 900 mm (parallel) . 78
VT
Figure D.3 – Approach when H ≥ 900 mm (orthogonal) . 79
VT
Figure D.4 – Approach when H < 900 mm (parallel) . 80
VT
Figure E.1 – T configuration with four parallel beam muting sensors, timing or
sequence control . 83
Figure E.2 – X configuration with two crossed beam muting sensors and timing control . 83
Figure E.3 – L configuration with two parallel beam muting sensors, timing or
sequence control . 84
Figure E.4 – Gap size beside the transported material, e.g. a pallet . 85
Figure E.5 – Four parallel beam muting sensors . 86
Figure E.6 – Minimum distances between MS1 and MS2 muting sensor beams . 87
Figure E.7 – Positioning of the muting sensors’ mounting height . 87
Figure E.8 – Avoidance of manipulation of muting by proximity sensors . 88
Figure E.9 – Crossed beam muting sensors not crossing the AOPD are not suitable. 89
Figure E.10 – Signal sequence: Four parallel muting sensor beams with sequence
control . 90
Figure E.11 – Signal sequence: Four parallel muting sensor beams with timing control . 91
Figure E.12 – Connection of four muting sensors to a control with two inputs . 92
Figure E.13 – Positioning of two crossed beam muting sensors . 93
Figure E.14 – Two crossed beam muting sensors with risk of entering the hazard zone . 95
Figure E.15 – Signal sequence and timing of two crossed beam muting sensors . 96
Figure E.16 – Height of crossing point . 97
Figure E.17 – Two parallel beam muting sensors – Exit only . 98
Figure E.18 – Signal diagram; two parallel beam muting sensors – Exit only, timing
control and muting terminated by the AOPD. 99
Figure E.19 – Signal diagram; two parallel beam muting sensors – Exit only, sequence
control and muting terminated by timer . 99
Figure E.20 – Signal diagram; uncontrolled muting timeout with two beam muting . 100
Figure E.21 – Signal diagram - Muting timeout controlled by conveyor signal . 101
Figure E.22 – Signal sequence example with static muting enable signal . 102
Figure E.23 – Signal sequence of a dynamic muting enable signal. 103
Figure E.24 – Signal sequence of a combined muting enable and timeout control signal . 104
Figure E.25 – Lateral gap protection with additional swing doors – Top view . 105
Figure E.26 – Lateral gap protection with additional swing doors – Front view . 105
Figure E.27 – Swing doors in combination with muting . 107
Figure E.28 – Lateral gap protection in a muting system by additional vertical AOPD . 108
Figure E.29 – Production line incorporating two conveyors (two hazard zones)
(incorrect application) . 109
Figure E.30 – Production line incorporating two conveyors (two hazard zones) . 110
Figure F.1 – Example of automatic selection of active detection zones . 111
Figure F.2 – Example of automatic detection zone selection with an AOPD (light
curtain) . 112
Figure F.3 – Example of automatic detection zone selection with vertically mounted
AOPDDR . 113
Figure G.1 – Detection principle of through-beam AOPD. 114
Figure G.2 – Through-beam AOPD using mirrors . 114
Figure G.3 – Retro-reflective AOPD . 115
Figure G.4 – Detection principle of AOPDDR . 115
Figure G.5 – Detection principle of VBPDST . 116
Figure G.6 – Detection principle of RPD . 117
Figure H.1 – General safety block diagram for a muting system . 119
Figure H.2 – Safety-related block diagram of a 2-sensors MS-SB . 121
Figure H.3 – Safety-related block diagram of a 4-sensors MS-SB and its pre-
transformation. 122

Table 1 – ESPE Types and achievable PL or SIL . 27
Table D.1 –Overview of orthogonal versus parallel approach . 77
Table E.1 – Truth table, four parallel beam muting sensors with sequence control . 89
Table H.1 – Safety performance of muting sensor subsystems according to
ISO 13849-1 . 123
Table H.2 – Safety performance of muting sensor subsystems according to IEC 62061 . 125

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
Safety of machinery -
Application of protective equipment to detect the presence 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
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8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
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9) IEC draws attention to the possibility that the implementation of this document may involve the use of (a)
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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 62046 has been prepared by IEC technical committee 44: Safety of machinery –
Electrotechnical aspects. It is an International Standard.
This second edition cancels and replaces the first edition published in 2018. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the first edition:
a) restructuring of the document to aid the user;
b) additional information on vision and radar systems;
c) muting requirements have been updated;
d) information on whole body access has been added;
e) whole body access has also been covered in more detail;
f) alignment to changes in ISO 13855.
The text of this International Standard is based on the following documents:
Draft Report on voting
44/1080/FDIS 44/1088/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.
INTRODUCTION
This document provides requirements and information on the application of sensitive protective
equipment (SPE), which employs sensing devices to detect persons, in order to reduce or
minimize a risk from hazardous parts of machinery, without providing a physical barrier.
The objective of this document is to assist standards writing committees responsible for
developing machine standards (type-C Standards), machine designers, manufacturers and
refurbishers, machine safety certification organizations, workplace authorities and others on
the proper application of sensitive protective equipment to machinery.
Figure 1 shows the general context and the intended use of this document.
Clause 1 to Clause 5, Clause 7 and Clause 8 of this document apply to all sensitive protective
equipment included in the scope, Clause 6 contains guidance for the application of specific
kinds of sensitive protective equipment.
The principles of this document can be useful in the application of devices using other detection
technologies but this document does not give specific requirements for those devices.
This document considers devices standardized in the IEC 61496 series and the ISO 13856
series. Unless a product-specific safety-related standard for devices using other sensing
technologies is published, their suitability as the sole means of protection from machine hazards
is unknown. The selection and use of devices for which there is no product-specific safety-
related standard because their behaviour, particularly under fault conditions, is not known to be
sufficiently predictable should be selected only after adequate research.
A SIL (safety integrity level, as described in IEC 62061 or IEC 61508) or PL (performance level,
as described in ISO 13849-1) is not sufficient as an indication of a device's suitability for use
as a safeguard. Suitability depends on appropriate sensing means, environmental conditions
especially those that can affect the detection capability, behaviour under fault conditions, etc.
Figure 1 – Relationship of this document to other standards

1 Scope
This document specifies requirements for the selection, positioning, configuration and
commissioning of sensitive protective equipment (SPE) to detect the momentary or continued
presence of persons in order to protect those persons from dangerous part(s) of machinery in
industrial applications. This document covers the application of electro-sensitive protective
equipment (ESPE) specified in the IEC 61496 series and pressure-sensitive mats and floors
specified in ISO 13856-1.
It takes into account the characteristics of the machinery, the sensitive protective equipment,
the environment and human interaction by persons of 14 years and older.
This document includes informative annexes to provide guidance on the application of sensitive
protective equipment to detect the presence of persons. These annexes contain examples to
illustrate the principles of this document. These examples are not intended to be the only
solutions to a given application and are not intended to restrict innovation or advancement of
technology. The examples are provided only as representative solutions to illustrate some of
the concepts of integration of sensitive protective equipment, and have been simplified for
clarity, so they can be incomplete.
It is intended that this document is used in conjunction with ISO 13855.
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 62061:2021, Safety of machinery - Functional safety of safety-related control systems
IEC 62061:2021/AMD1:2024
IEC TS 61496-4-2:2022, Safety of machinery - Electro-sensitive protective equipment -
Part 4-2: Particular requirements for equipment using vision based protective devices (VBPD)
- Additional requirements when using reference pattern techniques (VBPDPP)
IEC TS 61496-4-3:2022, Safety of machinery - Electro-sensitive protective equipment -
Part 4-3: Particular requirements for equipment using vision based protective devices (VBPD)
- Additional requirements when using stereo vision techniques (VBPDST)
ISO 13849-1:2023, Safety of machinery - Safety-related parts of control systems - Part 1:
General principles for design
ISO 13855:2024, Safety of machinery - Positioning of safeguards with respect to the approach
of the human body
3 Terms, definitions and abbreviated terms
3.1 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
3.1.1
active opto-electronic protective device
AOPD
device whose sensing function is performed by opto-electronic emitting and receiving elements
detecting the interruption of optical radiations generated, within the device, by an opaque object
present in the specified detection zone (or for a light beam device, on the axis of the light beam)
[SOURCE: IEC 61496-2:2020, 3.201, modified – The note to entry has been removed.]
3.1.2
active opto-electronic protective device responsive to diffuse reflection
AOPDDR
assembly using active optical radiation to detect the diffuse reflection of an object present in a
detection zone specified in two or three dimensions
[SOURCE: IEC 61496-3:2025, 3.301]
3.1.3
automatic selection of active detection zone
optional function that permits the selection/deselection of the active safety-related detection
zone of sensitive protective equipment while still providing protection during the hazardous
machine cycle
Note 1 to entry: Examples include selection of pre-defined blanking or reduced resolution configurations; see
IEC 61496-2:2020, Clause A.12.
Note 2 to entry: The safety-related logic for the automatic selection of active detection zones may be within the
sensitive protective equipment or may be applied externally from within the safety-related parts of the control system.
Note 3 to entry: The automatic selection of safety-related detection zones is not a muting function; see
IEC 61496-3:2025, A.10.1, Note 2.
3.1.4
blanking
optional function that permits an object of a size greater than the detection capability of the
ESPE to be located within the detection zone without causing an OFF-state of the OSSD(s)
Note 1 to entry: Blanked beams are monitored for continued interruption of light.
[SOURCE: IEC 61496-1:2020, 3.1, modified – Note 1 to entry has been modified, Note 2 to
entry has been removed.]
3.1.5
detection capability
d
sensing function parameter limit specified by the supplier that will cause actuation of the
sensitive protective equipment
[SOURCE: IEC 61496-1:2020, 3.3, modified – In the definition, "electro-" has been removed
from the term "electro-sensitive".]
3.1.6
detection zone
zone within which a specified test piece is detected by the sensitive protective equipment
Note 1 to entry: The detection zone can also be a point, line, plane or volume.
Note 2 to entry: ISO 13856-1 uses the term "effective sensing area" when describing pressure-sensitive mats and
pressure-sensitive floors. In this document the terms "detection zone" and "effective sensing area" are used
synonymously.
[SOURCE: ISO 13855:2024, 3.1.7 , modified – "or volume" has been added to Note 1 to entry.]
3.1.7
effective detection capability
d
e
sensing function parameter limit set by the integrator of the device that will cause its actuation
Note 1 to entry: Some sensitive protective equipment provide a provision for the detection capability to be modified
for the application.
[SOURCE: ISO 13855:2024, 3.1.4, modified – Note 1 to entry has been added.]
3.1.8
electro-sensitive protective equipment
ESPE
assembly of devices and/or components working together for protective tripping or presence-
sensing purposes and comprising as a minimum
– a sensing device;
– controlling/monitoring devices;
– output signal switching devices and/or a safety-related data interface
[SOURCE: IEC 61496-1:2020, 3.5, modified – Notes 1 and 2 to entry have been removed.]
3.1.9
external device monitoring
EDM
means by which external devices are monitored for their correct operation
Note 1 to entry: EDM may be a function integrated into a SPE or control logic unit.
3.1.10
failure
loss of ability of an item to perform as required
Note 1 to entry: A failure of an item is an event that results in a fault of that item: see "fault" (IEV 192-04-01).
Note 2 to entry: Qualifiers, such as catastrophic, critical, major, minor, marginal and insignificant, can be used to
categorize failures according to the severity of consequences, the choice and definitions of severity criteria
depending upon the field of application.
Note 3 to entry: Qualifiers, such as misuse, mishandling and weakness, can be used to categorize failures
according to the cause of failure.
Note 4 to entry: In practice, the terms fault and failure are often used synonymously.
[SOURCE: IEC 60050-192:2015, 192-03-01, modified – Note 4 to entry was added.]
3.1.11
failure to danger
failure which prevents or delays all output signal switching devices going to, and/or remaining
in the OFF-state in response to a condition which, in normal operation, would result in their so
doing
[SOURCE: IEC 61496-1:2020, 3.8]
3.1.12
fault
inability to perform as required, due to an internal state
Note 1 to entry: A fault of an item results from a failure, either of the item itself, or from a deficiency in an earlier
stage of the life cycle, such as specification, design, manufacture or maintenance. See latent fault (192-04-08).
Note 2 to entry: Qualifiers, such as specification, design, manufacture, maintenance or misuse, may be used to
indicate the cause of a fault.
Note 3 to entry: The type of fault may be associated with the type of associated failure, e.g. wear-out fault and
wear-out failure.
Note 4 to entry: The adjective “faulty” designates an item having one or more faults.
[SOURCE: IEC 60050-192:2015, 192-04-01]
3.1.13
final switching device
FSD
component of the machine’s safety-related control system that interrupts the circuit to the
machine primary control element (MPCE) when the output signal switching device (OSSD) goes
to the OFF-state
[SOURCE: IEC 61496-1:2020, 3.10]
3.1.14
hazard
potential source of harm
Note 1 to entry: The word "hazard" is generally used in conjunction with other words defining its origin or the nature
of the expected injury or damage to health: electrical shock hazard, crushing hazard, shea
...