IEC TS 62998-3:2023

IEC TS 62998-3 ®
Edition 1.0 2023-08
TECHNICAL
SPECIFICATION
Safety of machinery – Safety-related sensors used for the protection of
persons –
Part 3: Sensor technologies and algorithms

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IEC TS 62998-3 ®
Edition 1.0 2023-08
TECHNICAL
SPECIFICATION
Safety of machinery – Safety-related sensors used for the protection of

persons –
Part 3: Sensor technologies and algorithms

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 13.110; 21.020 ISBN 978-2-8322-7174-2

– 2 – IEC TS 62998-3:2023 © IEC 2023
CONTENTS
FOREWORD . 4
INTRODUCTION . 6
1 Scope . 7
2 Normative references . 7
3 Terms and definitions . 8
4 Sensor technologies . 11
4.1 General considerations . 11
4.2 SRS using visible light . 13
4.2.1 General . 13
4.2.2 Material considerations . 13
4.2.3 Measurement method considerations . 13
4.2.4 Sensing unit arrangement considerations . 14
4.3 SRS using near infrared radiation . 17
4.3.1 General . 17
4.3.2 Material considerations . 17
4.3.3 Measurement method considerations . 18
4.3.4 Sensing unit arrangement considerations . 18
4.4 SRS using middle infrared radiation . 19
4.4.1 General . 19
4.4.2 Material considerations . 20
4.4.3 Measurement method considerations . 20
4.4.4 Sensing unit arrangement considerations . 20
4.5 SRS using millimetre wave radiation . 21
4.5.1 General . 21
4.5.2 Material considerations . 21
4.5.3 Measurement method considerations . 21
4.5.4 Sensing unit arrangement considerations . 22
4.6 SRS using radio/millimetre wave radiation . 23
4.6.1 General . 23
4.6.2 Tag considerations . 23
4.6.3 Measurement method considerations . 23
4.6.4 Sensing unit arrangement considerations . 24
4.7 SRS using ultrasound wave radiation . 25
4.7.1 General . 25
4.7.2 Material considerations . 25
4.7.3 Measurement method considerations . 25
4.7.4 Sensing unit arrangement considerations . 26
5 Algorithm related considerations . 27
5.1 General . 27
5.2 Design and development phase . 30
5.2.1 General . 30
5.2.2 Achieve the detection of objects . 32
5.2.3 Improve the dependability of the detection capability . 33
5.2.4 Provide confidence information at the output unit . 33
5.3 Integration and installation phase . 33
5.3.1 General . 33

5.3.2 Achieve improved detection of objects . 35
5.3.3 Improve the dependability of the detection capability . 36
5.3.4 Provide confidence information at the output unit . 36
5.4 Maintenance phase . 36
Annex A (informative) Physical property reflectivity for visible light or near infrared
radiation . 38
A.1 Process in accordance with IEC TS 62998-1 . 38
A.2 Persons or parts of a person . 39
Annex B (informative) Physical property reflectivity for millimetre wave radiation . 42
Annex C (informative) Physical property temperature for middle infrared radiation . 44
C.1 Process in accordance with IEC TS 62998-1 . 44
C.2 Exemplary determination of the temperature . 45
Annex D (informative) Physical property reflectivity for ultrasound wave radiation . 47
Bibliography . 50

Figure 1 – Co-located and stationary sensing unit arrangement . 15
Figure 2 – Separated and stationary sensing unit arrangement . 15
Figure 3 – Multiple and stationary sensing unit arrangement . 16
Figure 4 – Co-located and moving sensing unit arrangement . 16
Figure 5 – Separated and moving sensing unit arrangement . 16
Figure 6 – Multiple and moving sensing unit arrangement . 16
Figure 7 – Exemplary combined stationary and moving sensing unit arrangement. 17
Figure 8 – Exemplary multiple combined and moving sensing unit arrangement . 17
Figure 9 – Algorithms exemplary applied to an SRS or an SRSS . 28
Figure 10 – Flowchart for algorithm based on requirements . 29
Figure 11 – Flowchart for algorithm based on training data . 30
Figure 12 – Exemplary use of algorithm for peak extraction . 31
Figure 13 – Exemplary use of algorithm to combine measurement information . 32
Figure 14 – Exemplary combination of two SRS in an SRSS . 34
Figure 15 – Exemplary integration of SRS measurement information in an SRSS . 35
Figure C.1 – Illustration of temperature measurement . 46
Figure D.1 – Object ultrasonic reflectivity quantified by acoustic impedance or
reflection coefficient . 47
Figure D.2 – Object ultrasonic reflectivity quantified by radar cross section . 48

Table 1 – Specific sensor types used as part of SRS . 12
Table A.1 – Range of diffuse reflectance values of human skin if detection of skin can
be derived from the intended use . 39
Table A.2 – Range of diffuse reflectance values of clothes if detection of parts of
persons can be derived from the intended use . 40
Table A.3 – Diffuse reflectance values if detection of the whole body of persons can be
derived from the intended use . 41

– 4 – IEC TS 62998-3:2023 © IEC 2023
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
SAFETY OF MACHINERY – SAFETY-RELATED SENSORS
USED FOR THE PROTECTION OF PERSONS

Part 3: Sensor technologies and algorithms

FOREWORD
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