oSIST prEN 746-1:2020

SLOVENSKI STANDARD
oSIST prEN 746-1:2020
01-marec-2020
Industrijska termoprocesna oprema - 1. del: Splošne varnostne zahteve za
industrijsko termoprocesno opremo
Industrial thermoprocessing equipment - Part 1: Common safety requirements for
industrial thermoprocessing equipment
Industrielle Thermoprozessanlagen und dazugehörige Prozesskomponenten -
Sicherheitsanforderungen - Teil 1: Allgemeine Sicherheitsanforderungen an industrielle
Thermoprozessanlagen
Équipements thermiques industriels - Partie 1: Prescriptions générales de sécurité pour
les équipements thermiques industriels
Ta slovenski standard je istoveten z: prEN 746-1
ICS:
25.180.01 Industrijske peči na splošno Industrial furnaces in general
oSIST prEN 746-1:2020 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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oSIST prEN 746-1:2020


DRAFT
EUROPEAN STANDARD
prEN 746-1
NORME EUROPÉENNE

EUROPÄISCHE NORM

January 2020
ICS 25.180.01 Will supersede EN 746-1:1997+A1:2009
English Version

Industrial thermoprocessing equipment - Part 1: Common
safety requirements for industrial thermoprocessing
equipment
Équipements thermiques industriels - Partie 1: Industrielle Thermoprozessanlagen und dazugehörige
Prescriptions générales de sécurité pour les Prozesskomponenten - Sicherheitsanforderungen - Teil
équipements thermiques industriels 1: Allgemeine Sicherheitsanforderungen an industrielle
Thermoprozessanlagen
This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee
CEN/TC 186.

If this draft becomes a European Standard, 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.

This draft European Standard was established by CEN 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, Turkey and
United Kingdom.

Recipients of this draft are invited to submit, with their comments, notification of any relevant patent rights of which they are
aware and to provide supporting documentation.

Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without
notice and shall not be referred to as a European Standard.


EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2020 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 746-1:2020 E
worldwide for CEN national Members.

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Contents
European foreword . 4
Introduction . 5
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 8
4 Safety requirements and/or protective measures . 8
4.1 General . 8
4.1.1 Requirements . 8
4.1.2 General design and construction requirements . 9
4.2 Mechanical safety . 11
4.2.1 General . 11
4.2.2 Crushing . 11
4.2.3 Shearing . 12
4.2.4 Entanglement. 12
4.2.5 Drawing-in . 12
4.2.6 Impact . 12
4.2.7 High-pressure fluid ejection . 12
4.2.8 Ejection of parts . 13
4.2.9 Slip/trip . 13
4.2.10 Falls . 13
4.2.11 Transport . 13
4.3 Electrical safety . 13
4.3.1 Electrical equipment of TPE . 13
4.3.2 Electroheat installations/equipment . 14
4.4 Thermal and cryogenic safety . 14
4.4.1 General . 14
4.4.2 Contact with hot/cold surfaces . 14
4.4.3 Fire/explosion . 14
4.4.4 Ejection of hot particles, workpieces and process liquids . 16
4.4.5 Thermal stress and other physiological effects . 16
4.5 Noise . 16
4.5.1 General . 16
4.5.2 Interference with communications . 17
4.6 Vibration . 17
4.7 Radiation safety . 17
4.7.1 General . 17
4.7.2 Non-ionizing radiation . 17
4.7.3 Ionizing radiation. 18
4.8 Materials and substances processed, used or exhausted . 18
4.8.1 General . 18
4.8.2 Harmful by-products . 18
4.8.3 Fire/explosion . 18
4.9 Ergonomics . 19
4.10 Hazard combination . 19
4.11 Malfunction . 19
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4.11.1 Failure of power supply and auxiliary fluids . 19
4.11.2 Errors of fitting/assembly during installation. 19
4.11.3 Effect of malfunction of control system/component safety devices . 19
4.12 Missing and incorrectly fitted safety devices . 20
4.12.1 General . 20
4.12.2 Power supply disconnection devices . 20
5 Verification . 20
6 Information for use . 23
6.1 General requirements . 23
6.2 Location and nature of the information for use . 24
6.3 Signals and warning devices . 24
6.3.1 General . 24
6.3.2 Marking . 24
6.3.3 Personnel protection . 25
6.3.4 Warning signs . 25
6.4 Instruction handbooks/manuals . 25
Annex A (informative) List of significant hazards . 27
Annex B (informative) List of common industrial furnaces and associated processing
equipment . 38
B.1 Metallurgical and metal-working plants . 38
B.2 Glass-making plants . 39
B.3 Ceramic-manufacturing plants . 39
B.4 Cement-, lime- and gypsum-manufacturing plants . 40
B.5 Chemical/petrochemical plants . 40
B.6 Waste incineration . 41
B.7 Other industries . 41
Annex C (informative) Typical test report . 42
Annex D (informative) Work-permit authorization . 44
Annex ZA (informative) Relationship between this European Standard and the essential
requirements of Directive 2006/42/EC aimed to be covered . 47
Bibliography . 51

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European foreword
This document (prEN 746-1:2020) has been prepared by Technical Committee CEN/TC 186 “Industrial
thermoprocessing - Safety”, the secretariat of which is held by DIN.
This document is currently submitted to the CEN Enquiry.
This document will supersede EN 746-1:2010.
Based on EN 746-1:2010, ISO 13577-1 was developed in 2016. This ISO standard differs considerably
from the original EN 746-1:2010. The contents of this completely renewed prEN 746-1:2020 are based
on ISO 13577-1:2016).
This document has been prepared under a mandate given to CEN by the European Commission and the
European Free Trade Association, and supports essential requirements of EU Directive(s).
For relationship with EU Directive(s), see informative Annex ZA, which is an integral part of this
document.
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Introduction
This document is a type-C standard as stated in EN ISO 12100:2010.
The machinery concerned and the extent to which hazards, hazardous situations or hazardous events are
covered are indicated in the Scope of this document.
When requirements of this type-C standard are different from those which are stated in type-A or -B
standards, the requirements of this type-C standard take precedence over the requirements of the other
standards for machines that have been designed and built according to the requirements of this type-C
standard.
Industrial furnaces and associated processing equipment (TPE) generally consists of the following
components:
— processing chambers (e.g. steel construction with lining or without lining);
— heating systems;
— protective system;
— control and instrumentation system/operator-control level.
NOTE As stated in the scope, prEN 746-1:2020 does not cover blast furnaces, converters (in steel plants),
boilers and equipment not covered by EN ISO 12100:2010.
The requirements for protective systems are specified in prEN 746-11:2020.
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1 Scope
This document specifies the general safety requirements common to industrial furnaces and associated
processing equipment (TPE).
This document deals with the significant hazards, hazardous situations or hazardous events relevant to
TPE, as listed in Annex A, when TPE is used as intended and also under conditions of misuse that are
reasonably foreseeable by the manufacturer.
Annex B provides a list of common industrial furnaces and associated processing equipment.
This document specifies the requirements intended to be met by the manufacturer to ensure the safety
of persons and property during commissioning, start-up, operation, shut-down, maintenance periods and
dismantling, as well as in the event of foreseeable faults or malfunctions that can occur in the equipment.
These general safety requirements apply to all TPE, unless an exception is given in other parts of
EN 746 series dealing with specific equipment. The provisions of other parts of EN 746 that directly apply
to specific types of TPE take precedence over the provisions of this document.
This document is not applicable to
— blast furnaces, direct reduction furnaces and gas converters;
— steam and hot water boilers;
— fired appliances in the refining, petrochemical and chemical industries;
— sulphur thermal reactors ("Claus plants").
As long as no other standard is applicable for thermoprocess equipment (TPE), the requirements of this
standard are applicable.
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.
EN 349:1993+A1:2008, Safety of machinery — Minimum gaps to avoid crushing of parts of the human body
EN 547-1:1996+A1:2008, Safety of machinery — Human body measurements — Part 1: Principles for
determining the dimensions required for openings for whole body access into machinery
EN 547-2:1996+A1:2008, Safety of machinery — Human body measurements — Part 2: Principles for
determining the dimensions required for access openings
prEN 746-2:2020, Industrial furnaces and associated processing equipment — Safety — Part 2:
Combustion and fuel handling systems1
prEN 746-3:2020, Industrial furnaces and associated processing equipment — Safety — Part 3: Generation
1
and use of protective and reactive atmosphere gases

1
See ISO 13577-3:2016.
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prEN 746-11:2020, Industrial furnace and associated processing equipment — Safety — Part 11:
Protective systems1
EN 1547:2001+A1:2009, Industrial thermoprocessing equipment — Noise test code for industrial
thermoprocessing equipment including its ancillary handling equipment
2
ISO 7000:2019, Graphical symbols for use on equipment — Registered symbols
ISO 7010:2019, Graphical symbols — Safety colours and safety signs — Registered safety signs
EN ISO 7243:2017, Ergonomics of the thermal environment - Assessment of heat stress using the WBGT (wet
bulb globe temperature) index (ISO 7243:2017)
EN ISO 7731:2008, Ergonomics — Danger signals for public and work areas — Auditory danger signals
(ISO 7731:2003)
EN ISO 7933:2004, Ergonomics of the thermal environment — Analytical determination and interpretation
of heat stress using calculation of the predicted heat strain (ISO 7933:2004)
ISO 11429:1996, Ergonomics — System of auditory and visual danger and information signals
EN ISO 11690-2:1996, Acoustics ― Recommended practice for the design of low-noise workplaces
containing machinery ― Part 2: Noise control measures (ISO 11690-2:1996)
EN ISO 12100:2010, Safety of machinery — General principles for design — Risk assessment and risk
reduction (ISO 12100:2010)
ISO 13574:2015, Industrial furnaces and associated processing equipment — Vocabulary
EN ISO 13732-1:2008, Ergonomics of the thermal environment — Methods for the assessment of human
responses to contact with surfaces — Part 1: Hot surfaces (ISO 13732-1:2006)
EN ISO 13850:2015, Safety of machinery — Emergency stop function — Principles for design (ISO
13850:2015)
EN ISO 13849-1:2015, Safety of machinery — Safety-related parts of control systems — Part 1: General
principles for design (ISO 13849-1:2015)
EN ISO 13857:2008, Safety of machinery — Safety distances to prevent hazard zones being reached by
upper and lower limbs (ISO 13857:2008)
EN ISO 14118:2018, Safety of machinery — Prevention of unexpected start-up (ISO 14118:2017)
EN ISO 14119:2013, Safety of machinery — Interlocking devices associated with guards — Principles for
design and selection (ISO 14119:2013)
EN ISO 14120:2015, Safety of machinery — Guards — General requirements for the design and
construction of fixed and movable guards (ISO 14120:2015)

2
The graphical symbol collections of ISO 7000, ISO 7001 and ISO 7010 are also available on line in the ISO web
store. For more information, consult http://www.iso.org/iso/fr/publications_and_e-products/databases.htm.
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EN ISO 14122-2:2016, Safety of machinery — Permanent means of access to machinery — Part 2: Working
platforms and walkways (ISO 14122-2:2016)
EN ISO 14122-3:2016, Safety of machinery — Permanent means of access to machinery — Part 3: Stairs,
stepladders and guard-rails (ISO 14122-3:2016)
EN ISO 14123-1:2015, Safety of machinery — Reduction of risks to health resulting from hazardous
substances emitted by machinery — Part 1: Principles and specifications for machinery manufacturers (ISO
14123-1:2015)
EN IEC 60079-0:2018, Explosive atmospheres — Part 0: Equipment — General requirements (IEC 60079-
0:2017)
EN 60204-1:2018, Safety of machinery — Electrical equipment of machines — Part 1: General
requirements (IEC 60204-1:2016)
EN 60519 (all parts), Safety in electroheat installations (IEC 60519 (all parts))
EN 60519-6:2011, Safety in electroheat installations — Part 6: Specifications for safety in industrial
microwave heating equipment (IEC 60519-6:2011)
EN 60825-1:2014, Safety of laser products — Part 1: Equipment classification and requirements (IEC
60825-1:2014)
EN 61310-1:2008, Safety of machinery — Indication, marking and actuation — Part 1: Requirements for
visual, acoustic and tactile signals (IEC 61310-1:2007)
EN 61310-2:2008, Safety of machinery — Indication, marking and actuation — Part 2: Requirements for
marking (IEC 61310-2:2007)
EN 62061:2005, Safety of machinery — Functional safety of safety-related electrical, electronic and
programmable electronic control systems (IEC 62061:2005)
EN 62598:2013, Nuclear instrumentation — Constructional requirements and classification of radiometric
gauges (IEC 62598:2011)
3 Terms and definitions
For the purposes of this document, the terms and definitions given in EN ISO 12100:2010 and
ISO 13574:2015 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 https://www.iso.org/obp
4 Safety requirements and/or protective measures
4.1 General
4.1.1 Requirements
The TPE shall comply with the safety requirements and/or protective measures described in Clause 4
and shall be verified in accordance with Clause 5. In addition, the TPE shall be designed in accordance
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with the principles of EN ISO 12100:2010 for relevant hazards, but not significant hazards, which are
dealt with by this document.
Anticipated significant hazards are listed in Table A.1.
For ease of reference, Table A.1 also indicates the corresponding preventive measures and should be used
in conjunction with Clauses 4, 5 and 6.
Where particular requirements of the other parts of the EN 746 series apply, they shall supplement or
modify these general safety requirements.
4.1.2 General design and construction requirements
4.1.2.1 General
The manufacturer shall maintain evidence that all safety requirements of the design have been fulfilled.
The structural assembly, steel sections, auxiliaries and services (utilities) that form part of the TPE shall
be stable, suitable for function and the intended use.
In particular, the design shall include solutions and constructional details relating to the following:
— static stability of the TPE, including structures intended for containing the processed materials and
the materials entering and leaving the TPE;
— accessibility;
— maintenance and cleaning clearances;
— movement of material and machinery;
— safety in operation;
— health and safety at the workplace;
— protection against fire and prevention of explosion;
— emissions from the process;
— protection against earthquakes where seismic intensity exceeds 325 gal, as determined by the
seismic zone.
Cut-off, regulating and measuring devices, pipework and tanks carrying or containing fluids, which are
likely to solidify and/or have high viscosity, shall be protected against the effects of solidification and
subsequent blockage.
If internal parts of the TPE require frequent inspection, they shall be either provided with lighting
appropriate to the structure and the nature of the process or the user shall be advised to install suitable
lighting.
The design of the TPE and the action of the regulating and safety devices shall prevent:
a) unintended release of flammable or hazardous fluids to the outside of the TPE;
b) a backflow of flammable or hazardous fluids to pipes not intended for such fluids; and
c) flashback in the pipework.
The safety devices shall:
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— be suitable for the range of adjustment required for the regulation of the TPE; and
— not cause one device inadvertently to over-ride another.
Safety devices shall be fitted in such a manner that they are accessible and protected against harmful
effects. In particular, they shall withstand continuous operation in the area in which they are to be used.
Auxiliary fluids, such as lubricants, dielectric, diathermic and dynamic fluids, shall be selected to
minimize the hazard of their products of combustion resulting from a fire.
Drains that form part of the TPE shall discharge into a suitably isolated sump. Means shall be provided
for the collection and removal of such discharges.
Pipework distribution systems forming part of the TPE shall be designed to withstand corrosion.
Pipework distribution systems that form part of the equipment and can become dangerous if subjected
to extreme temperatures or pressures, wide variations in temperature or pressures, or voltage shall be
marked.
4.1.2.2 Stability
The TPE structures shall be designed to withstand their static and dynamic loads. The TPE shall be
designed for normal and foreseeable accidental thermal static and dynamic working stresses, including
those resulting from overpressurization or operation below atmospheric pressure.
The design shall also take account of vibration, wind pressure, impact and other foreseeable external
forces, including earthquakes.
4.1.2.3 Access
All parts of the TPE to which personnel require to have access for operation and maintenance shall be
served by adequate means of access, preferably fixed. Stairways, platforms and service floors shall be safe
and shall be equipped with adequate safeguards (see 4.2.10). Inspection and service floors of the TPE
shall be safe, well lit, well ventilated, protected against heat radiation and be fire-resistant (see 4.4.3.1).
Account shall be taken of the need for emergency escape routes to avoid the tra
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