SIST EN ISO 13577-4:2022

SLOVENSKI STANDARD
SIST EN ISO 13577-4:2022
01-september-2022
Industrijske peči in pripadajoča procesna oprema - Varnost - 4. del: Zaščitni
sistemi (ISO 13577-4:2022)
Industrial furnaces and associated processing equipment - Safety - Part 4: Protective
systems (ISO 13577-4:2022)
Industrielle Thermoprozessanlagen und dazugehörige Prozesskomponenten -
Sicherheitsanforderungen - Teil 4: Schutzsysteme (ISO 13577-4:2022)
Fours industriels et équipements associés - Sécurité - Partie 4: Systèmes de protection
(ISO 13577-4:2022)
Ta slovenski standard je istoveten z: EN ISO 13577-4:2022
ICS:
25.180.01 Industrijske peči na splošno Industrial furnaces in general
SIST EN ISO 13577-4:2022 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN ISO 13577-4:2022

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SIST EN ISO 13577-4:2022


EN ISO 13577-4
EUROPEAN STANDARD

NORME EUROPÉENNE

July 2022
EUROPÄISCHE NORM
ICS 13.100; 25.180.01
English Version

Industrial furnaces and associated processing equipment -
Safety - Part 4: Protective systems (ISO 13577-4:2022)
Fours industriels et équipements associés - Sécurité - Industrielle Thermoprozessanlagen und dazugehörige
Partie 4: Systèmes de protection (ISO 13577-4:2022) Prozesskomponenten - Sicherheitsanforderungen - Teil
4: Schutzsysteme (ISO 13577-4:2022)
This European Standard was approved by CEN on 27 June 2022.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this
European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references
concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN
member.

This European Standard exists in three official versions (English, French, German). A version in any other language made by
translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management
Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and
United Kingdom.





EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2022 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 13577-4:2022 E
worldwide for CEN national Members.

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SIST EN ISO 13577-4:2022
EN ISO 13577-4:2022 (E)
Contents Page
European foreword . 3

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SIST EN ISO 13577-4:2022
EN ISO 13577-4:2022 (E)
European foreword
This document (EN ISO 13577-4:2022) has been prepared by Technical Committee ISO/TC 244
"Industrial furnaces and associated processing equipment" in collaboration with Technical Committee
CEN/TC 186 “Industrial thermoprocessing - Safety” the secretariat of which is held by DIN.
This European Standard shall be given the status of a national standard, either by publication of an
identical text or by endorsement, at the latest by January 2023, and conflicting national standards shall
be withdrawn at the latest by January 2023.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
Any feedback and questions on this document should be directed to the users’ national standards
body/national committee. A complete listing of these bodies can be found on the CEN website.
According to the CEN-CENELEC Internal Regulations, the national standards organizations of the
following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria,
Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland,
Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of
North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and the
United Kingdom.
Endorsement notice
The text of ISO 13577-4:2022 has been approved by CEN as EN ISO 13577-4:2022 without any
modification.

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SIST EN ISO 13577-4:2022

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SIST EN ISO 13577-4:2022
INTERNATIONAL ISO
STANDARD 13577-4
Second edition
2022-07
Industrial furnaces and associated
processing equipment — Safety —
Part 4:
Protective systems
Fours industriels et équipements associés — Sécurité —
Partie 4: Systèmes de protection
Reference number
ISO 13577-4:2022(E)
© ISO 2022

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SIST EN ISO 13577-4:2022
ISO 13577-4:2022(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2022
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: +41 22 749 01 11
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
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SIST EN ISO 13577-4:2022
ISO 13577-4:2022(E)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 2
4 Design requirements for equipment in a protective system . 4
4.1 General . 4
4.2 Requirements for protective systems . 6
4.2.1 Overview of methods . 6
4.2.2 Method A . . . 7
4.2.3 Method BC . 8
4.2.4 Method D . 10
4.3 Fault assessment for the wired section of protective systems. 11
4.4 Failure of utilities . 12
4.5 Reset . 12
5 Information for use .12
Annex A (informative) Explanation of techniques and measures for avoiding systematic
faults .13
Annex B (normative) Wiring of protective systems .15
Annex C (informative) Examples for the determination of safety integrity level (SIL) or
performance level (PL) using the risk graph method .29
Annex D (informative) Example of a risk assessment for one safety instrumented function
using the method according to the IEC 61511:2016 series .45
Annex E (informative) Examples for protective functions .53
Annex F (normative) Requirements for application software .82
Bibliography .84
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SIST EN ISO 13577-4:2022
ISO 13577-4:2022(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www.iso.org/patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to
the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see
www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 244, Industrial furnaces and associated
processing equipment, in collaboration with the European Committee for Standardization (CEN)
Technical Committee CEN/TC 186, Industrial thermoprocessing - Safety, in accordance with the
Agreement on technical cooperation between ISO and CEN (Vienna Agreement).
This second edition cancels and replaces the first edition (ISO 13577-4:2014), which has been technically
revised.
The main changes are as follows:
— to provided better clarity methods B and C were combined to create a new method BC,
— Annex E was rewritten to provide several new examples to better reflect the intent for previously
misunderstood elements,
— Annex B was modified to include clearer language and examples of normative wiring. The original
Annex F was merged,
— created wording to provide a better alignment with IEC 62061, IEC 61511, and ISO 13849-1.
A list of all parts in the ISO 13577 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.
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SIST EN ISO 13577-4:2022
ISO 13577-4:2022(E)
Introduction
This document was developed to specify the requirements of a protective system, which is a safety-
related control system (SCS) of industrial furnaces and associated processing equipment (TPE). It is
intended that in designing the protective system of TPE, manufacturers of TPE choose from the three
methods provided in this document. Requirements for safety-related control functions of TPE are
specified in ISO 13577-1, ISO 13577-2, and ISO 13577-3.
This document is intended to be used jointly with ISO 13577-1, ISO 13577-2 and ISO 13577-3. Since the
other parts of the ISO 13577 series are type-C standards of ISO 12100, TPE are required to be designed
in accordance with the principles of ISO 12100. The type-B standards of ISO 12100 for SCS are IEC 62061
or ISO 13849-1, which always assume high-demand applications. However, there are cases in which a
risk assessment according to the IEC 61511 series, which provides the option of a low-demand rate on
the protective system, is more suitable for the design of a TPE protective system.
In principle, when requirements of ISO 13577-1, ISO 13577-2 and ISO 13577-3 (type-C standards)
are different from those which are stated in type-A or -B standards, the requirements of the type-C
standards take precedence over the requirements of the other standards for machines, which have been
designed and built according to the requirements of the type-C standards. Therefore, this document
permits risk assessment for safety-related electrical control systems (SRECS) in which risk assessment
based on the IEC 61511 series can be chosen as an alternative.
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SIST EN ISO 13577-4:2022

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SIST EN ISO 13577-4:2022
INTERNATIONAL STANDARD ISO 13577-4:2022(E)
Industrial furnaces and associated processing
equipment — Safety —
Part 4:
Protective systems
1 Scope
This document specifies the requirements for protective systems used in industrial furnaces and
associated processing equipment (TPE).
The functional requirements to which the protective systems apply are specified in ISO 13577-1
ISO 13577-2 and ISO 13577-3.
This document is not applicable to blast furnaces, converters (in steel plants), boilers, fired heaters
(including reformer furnaces) in the petrochemical and chemical industries.
This document is not applicable to electrical cabling and power cabling upstream of the TPE control
panel/protective system.
This document is not applicable to the protective systems manufactured before the date of its
publication.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 13574, Industrial furnaces and associated processing equipment — Vocabulary
1)
ISO 13849-1:—, Safety of machinery — Safety-related parts of control systems — Part 1: General
principles for design
IEC 60947-4-1:2018, Low-voltage switchgear and controlgear — Part 4-1: Contactors and motor-starters -
Electromechanical contactors and motor-starters
IEC 60947-5-1:2016, Low-voltage switchgear and controlgear — Part 5-1: Control circuit devices and
switching elements - Electromechanical control circuit devices
IEC 60204-1:2016, Safety of machinery — Electrical equipment of machines — Part 1: General requirements
IEC 60730-2-5:2013+AMD1: 2017+ AMD2: 2020 CSV, Automatic electrical controls for household and
similar use — Part 2-5: Particular requirements for automatic electrical burner control systems
IEC 61508-1:2010, Functional safety of electrical/electronic/programmable electronic safety-related
systems — Part 1: General requirements
IEC 61508-2:2010, Functional safety of electrical/electronic/programmable electronic safety-related
systems — Part 2: Requirements for electrical/electronic/programmable electronic safety-related systems
IEC 61508-3:2010, Functional safety of electrical/electronic/programmable electronic safety-related
systems — Part 3: Software requirements
1) Fourth edition under preparation. Stage at the time of publication: ISO/DIS 13849-1:2022.
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SIST EN ISO 13577-4:2022
ISO 13577-4:2022(E)
IEC 61508-4:2010, Functional safety of electrical/electronic/programmable electronic safety-related
systems — Part 4: Definitions and abbreviations
IEC 61508-5:2010, Functional safety of electrical/electronic/programmable electronic safety-related
systems — Part 5: Examples of methods for the determination of safety integrity levels
IEC 61508-6:2010, Functional safety of electrical/electronic/programmable electronic safety-related
systems — Part 6: Guidelines on the application of IEC 61508-2 and IEC 61508-3
IEC 61508-7:2010, Functional safety of electrical/electronic/programmable electronic safety-related
systems — Part 7: Overview of techniques and measures
IEC 61131-3:2013, Programmable controllers — Part 3: Programming languages
IEC 61511-1:2016, Functional safety — Safety instrumented systems for the process industry sector — Part
1: Framework, definitions, system, hardware and application programming requirements
IEC 61511-2:2016, Functional safety — Safety instrumented systems for the process industry sector — Part
2: Guidelines for the application of IEC 61511-1:2016
IEC 61511-3:2016, Functional safety — Safety instrumented systems for the process industry sector — Part
3: Guidance for the determination of the required safety integrity levels
IEC 62061:2021, Safety of machinery - Functional safety of safety-related control systems
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 13574 and the following apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1
final element
part of a protective system (3.6), that implements the physical action necessary to achieve or maintain a
safe state
Note 1 to entry: Examples are valves, switch gears, and motors, including their auxiliary elements, for example, a
solenoid valve and actuator if involved in the safety function.
[SOURCE: IEC 61511-1:2016, 3.2.22, modified — "BPCS or SIS" has been changed to read "protective
system" in the definition.]
3.2
flame detector device
device by which the presence of a flame is detected and signalled
Note 1 to entry: It can consist of a flame sensor (3.9), an amplifier, and a relay for signal transmission.
[SOURCE: ISO 13574:2015, 2.65, modified — The second sentence in the original definition is presented
as Note 1 to entry.]
3.3
logic function
function which performs the transformations between input information [provided by one or more
input functions or sensors (3.9)] and output information [used by one or more output functions or final
elements (3.1)]
Note 1 to entry: Logic functions are executed by the logic solver (3.4) of a protective system (3.6).
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SIST EN ISO 13577-4:2022
ISO 13577-4:2022(E)
[SOURCE: IEC 61511-1:2016, 3.2.35, modified — "input functions" has been changed to read "input
functions or sensors" and "output function" had been changed to read "output function or final
elements" in the definition; Notes 1 and 2 to entry in the original definition had been deleted and Note 1
to entry has been added.]
3.4
logic solver
part of a protective system (3.6) that performs one or more logic function(s) (3.3)
Note 1 to entry: Examples are electrical systems, electronic systems, programmable electronic systems,
pneumatic systems, and hydraulic systems. Sensors (3.9) and final elements (3.1) are not part of the logic solver.
[SOURCE: IEC 61511-1:2016, 3.2.36, modified — "either a BPCS or SIS" has been changed to read "a
protective system" in the definition; Note 1 to entry in the original definition has been deleted.]
3.5
programmable (logic) controller
PLC
digitally operating electronic operating system, designed for use in an industrial environment, which
uses a programmable memory for the internal storage of user-oriented instructions to implement
specific functions such as logic, sequencing, timing, counting and arithmetic, to control, through digital
and analogue inputs and outputs, various types of machines or processes
[SOURCE: IEC 61131-1:2003, 3.5, modified — The second sentence of the original definition and Note 1
to entry have been deleted.]
3.6
protective system
instrumented system used to implement one or more safety-related instrumented functions which is
composed of any combination of sensor(s) (3.9), logic solver(s) (3.4), and final elements (3.1)
Note 1 to entry: This can include safety-related instrumented control functions or safety-related instrumented
protection functions or both.
Note 2 to entry: For example, see Figure 2.
[SOURCE: ISO 13574:2015, 2.138, modified — Note 1 to entry has been merged with the definition.]
3.7
safety bus
bus system and/or protocol for digital network communication between safety devices (3.8), which is
designed to achieve and/or maintain a safe state of the protective system (3.6)
[SOURCE: ISO 13574:2015, 2.164]
3.8
safety device
device that is used to perform protective functions, either on its own or as a part of a protective system
(3.6)
EXAMPLE Sensors (3.9), limiters, flame monitors, burner control systems, logic systems, final elements (3.1),
and automatic shut-off valves.
3.9
sensor
device that produces a signal based on a process variable
EXAMPLE Transmitters, transducers, process switches, and position switches.
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SIST EN ISO 13577-4:2022
ISO 13577-4:2022(E)
3.10
system for permanent operation
system, which is intended to remain in the running position for longer than 24 h without interruption
[SOURCE: IEC 60730-2-5:2013+AMD1: 2017+ AMD2: 2020 CSV, 2.5.101]
3.11
system for non-permanent operation
system, which is intended to remain in the running position for less than 24 h
[SOURCE: IEC 60730-2-5:2013+AMD1: 2017+ AMD2: 2020 CSV, 2.5.102]
4 Design requirements for equipment in a protective system
4.1 General
Electrical installations and equipment shall comply with IEC 60204-1:2016 and withstand the intended
operating stresses and external influences and hazards identified in the risk assessment required at
the design stage. Electrical installation and equipment shall be protected against damage. In particular,
it shall be robust to withstand damage during continuous operation.
Devices shall be used in accordance with their instructions including safety manuals. Any device used
outside of its published instructions shall be verified and validated to be suitable for the intended
application.
Devices of a protective system shall withstand the environmental conditions according to
IEC 60204-1:2016, 4.4 and fulfil their intended function.
Sensors (e.g. pressure transmitters, temperature transmitters, flow transmitters) used in the protective
system shall be independent from the process control system.
NOTE 1 Operating information can be exchanged but cannot compromise the functional safety of the
protective system.
Safe state shall be realized by de-energized circuits only.
Functional safety requirement, as identified in the ISO 13577 series shall be in accordance with the
2)
IEC 61508:2010 series, the IEC 61511:2016 series, IEC 62061:2021 or ISO 13849-1:— as applicable, and
implemented with the required SIL/PL for each function.
For the determination of the performance level of a safety function according to ISO 13849-1:—, the
alternative procedure as stated in ISO 13849-1:—, 6.1.9 is not allowed.
Figure 1 is provided as an aid to understand the relationship between the various elements of TPE and
their ancillary equipment, the heating system, the process control system and the protective system.
2) Fourth edition under preparation. Stage at the time of publication: ISO/DIS 13849-1:2022.
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SIST EN ISO 13577-4:2022
ISO 13577-4:2022(E)
Figure 1 — Block diagram of control and protective systems
An appropriate group of techniques and measures shall be used that are designed to prevent the
introduction of systematic faults during the design and development of the hardware and software of
the protective system (see Annex A).
Failure due to short circuit in external wiring shall be avoided (see B.5 and Figure B.10).
The wiring of safety-relevant sensors and actuators, which are part of a protective system, usually are
made in the field, outside of electrical enclosures. Short circuits, cross-circuits and earth faults in that
field wiring can cause safety critical faults to the entire protective system. Cable loops for connecting
field devices shall be suitably routed and fastened to prevent damage to the cables.
In order to keep the entire protective system in a safe condition, the field wiring of safety-relevant
sensors and actuators (e.g. pressure switches, gas valves) shall be protected against mechanical damage
(including, e.g. vibration or bending) to prevent short circuits, cross circuits and earth faults.
NOTE 2 A method to protect against short circuits, cross circuits and earth faults is to use cable-ducts, cable
trays, or conduits for the field wiring.
If the protective system is operated in non-grounded, insulated mains, an insulation monitoring
device shall be foreseen. This isolation monitoring device immediately needs to isolate all poles of the
protective system from the mains in the event of the first fault detection.
Requirements for testing and testing intervals for protective systems shall be specified in the
instruction handbook. Except as permitted by method D, the testing of all safety functions shall be
performed at least annually. Method D shall be used if the testing of all safety functions is performed
beyond 1 year.
See Annexes C and D for examples of SIL/PL determinations.
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SIST EN ISO 13577-4:2022
ISO 13577-4:2022(E)
4.2 Requirements for protective systems
4.2.1 Overview of methods
Any one or a combination of the three (3) methods shall be used to implement a protective system for
the safety function(s) requirements identified in the ISO 13577 series; however, only one method shall
be used for any one specific safety function. The three methods are the following:
— method A as specified in 4.2.2;
— method BC as specified in 4.2.3;
— method D as specified in 4.2.4.
Figure 2 shows the basic configuration of a protective system.
Figure 2 — Basic configuration of a protective system
Figure 3 shows the basic characteristics of each method.
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SIST EN ISO 13577-4:2022
ISO 13577-4:2022(E)
Figure 3 — Method overview
NOTE 1 Software interconnections are links between software function blocks, safety PLC inputs, and safety
PLC outputs. These are similar to wired interconnections between
...