oSIST prEN 17942:2023

Gas welding equipment - Safety requirements for thermoprocess equipment with open firing oxy-fuel gas welding equipment

This document, together with EN 746-1, EN 746-2 and EN 746-11, specifies the safety requirements for industrial thermoprocessing equipment ( IThE) with "Open firing oxy-fuel gas welding equipment", as well as the relevant gas distribution and protective systems. This document applies to IThE supplied with fuel gases. IThE in the scope of application of this document shall be able to be operated under the following ambient conditions:
- temperature range;
- during operation: +5°C to +40°C;
- during transportation and storage: -5°C to +55°C;
- relative humidity: up to 90% at 20°C, non-condensing.
This document covers the significant hazards, hazardous situations and events listed in Appendix A for oxy-fuel IThE, associated gas supply systems and protective systems on the basis that they are used as intended and under the conditions specified by the manufacturer.
This document applies to:
- gas distribution system, beginning in the direction of flow with the manually isolation main shut-off valve at the inlet of the thermoprocessing equipment;
- burner, burner assembly and ignition devices, open firing;
- Safety control system (protective system).
This document is applicable to all types of combustion of fuel gases with atmospheric air, compressed air or oxygen. This document also includes necessary requirements for user information. This document does not apply to manual burners, systems for flame spraying and micro soldering torches.
This document does not apply to systems for welding, cutting and associated processes using plasma and laser technology. This document does not cover the hazards arising as a result of the release of flammable substances from the products processed in the IThE.
This document is not applicable to electrical wiring and heavy-current wiring connected upstream of the IThE control cabinet/control panel/protective system.
Noise and optical radiation can cause significant hazards when using gas welding equipment. These are not covered in this document.
This document is not applicable to oxy-fuel IThE, associated gas supply systems and protective systems manufactured before the date of publication of this document in the Official Journal of the EU.

Gasschweißgeräte - Sicherheitsanforderungen an industrielle Thermoprozess-Einrichtungen mit freibrennenden Gasschweißgeräten der Autogentechnik

Matériel de soudage au gaz - Prescriptions de sécurité pour les équipements thermiques avec matériel de soudage oxygaz à flamme nue

Oprema za plamensko varjenje - Varnostne zahteve za opremo za toplotne procese z odprtim plamenom

General Information

• Status: Not Published
• Public Enquiry End Date: 02-Feb-2023
• ICS: 25.160.30 - Welding equipment
• Technical Committee: VAR - Welding
• Current Stage: 4020 - Public enquire (PE) (Adopted Project)
• Start Date: 23-Nov-2022
• Due Date: 12-Apr-2023
• Completion Date: 31-Mar-2023
• Directive: 2006/42/EC - Directive 2006/42/EC of the European Parliament and of the Council of 17 May 2006 on machinery, and amending Directive 95/16/EC (recast)
• Directive: 2014/68/EU - Directive 2014/68/EU of the European Parliament and of the Council of 15 May 2014 on the harmonisation of the laws of the Member States relating to the making available on the market of pressure equipment
• Mandate: M/396 - Mandate to CEN and Cenelec for standardisation in the field of machinery
• Ref Project: prEN 17942 - Gas welding equipment - Safety requirements for thermoprocess equipment with open firing oxy-fuel gas welding equipment

Standards Content (Sample)

SLOVENSKI STANDARD
oSIST prEN 17942:2023
01-januar-2023
[Not translated]
Gas welding equipment - Safety requirements for thermoprocess equipment with open
firing oxy-fuel gas welding equipment
Gasschweißgeräte - Sicherheitsanforderungen an industrielle Thermprozessanlagen mit
freibrennenden Gasschweißgeräte der Autogentechnik
Matériel de soudage au gaz - Prescriptions de sécurité pour les équipements thermiques
avec matériel de soudage oxygaz à flamme nue
Ta slovenski standard je istoveten z: prEN 17942
ICS:
25.160.30 Varilna oprema Welding equipment
oSIST prEN 17942:2023 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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oSIST prEN 17942:2023

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oSIST prEN 17942:2023


DRAFT
EUROPEAN STANDARD
prEN 17942
NORME EUROPÉENNE

EUROPÄISCHE NORM

January 2023
ICS
English Version

Gas welding equipment - Safety requirements for
thermoprocess equipment with open firing oxy-fuel gas
welding equipment
Matériel de soudage au gaz - Prescriptions de sécurité Gasschweißgeräte - Sicherheitsanforderungen an
pour les équipements thermiques avec matériel de industrielle Thermprozessanlagen mit freibrennenden
soudage oxygaz à flamme nue Gasschweißgeräte der Autogentechnik
This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee
CEN/TC 121.

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, Türkiye 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
© 2023 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 17942:2023 E
worldwide for CEN national Members.

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Contents Page

European foreword . 4
Introduction . 5
1 Scope . 6
2 Normative references . 7
3 Terms and definitions . 11
4 Safety requirements, measures and ascertaining compliance . 12
4.1 General. 12
4.2 Gases . 13
4.2.1 General. 13
4.2.2 Gases in accordance with EN 437:2021 . 13
4.2.3 Acetylene . 13
4.2.4 Hydrogen. 14
4.2.5 Oxygen or oxygen-enriched combustion air . 14
4.3 Gas distribution system . 16
4.3.1 General. 16
4.3.2 Connections . 17
4.3.3 Interrupted lines . 17
4.3.4 Galvanic elements . 17
4.3.5 Gas warning devices – Stationary gas detector . 17
4.3.6 Hose lines and couplings . 18
4.3.7 Labelling . 18
4.3.8 Inspection and testing . 18
4.3.9 Condensate drains . 19
4.3.10 Purge points . 19
4.3.11 Safety devices to prevent gas back flow and flashback . 19
4.3.12 Pressure fluctuations . 20
4.3.13 Bypass . 20
4.3.14 Disconnection of prescribed safety devices . 20
4.3.15 Mandatory safety devices . 20
4.3.16 Industrial thermo-processing equipment . 21
4.3.17 Valve monitoring system . 22
4.3.18 Gas pressure regulator . 22
4.3.19 Pressure and flow monitors . 22
4.3.20 Filters/strainers . 23
4.3.21 Exhaust gas system . 23
4.3.22 Ignition system . 23
4.3.23 Individual manual shut-off valves for gas welding equipment . 24
4.3.24 Supply of pre-mixed fuel gas/air mixtures to the gas welding equipment . 24
4.3.25 Gas welding equipment . 24
4.3.26 Startup and ignition . 25
4.3.27 Safety time . 26
4.3.28 Flame failure . 27
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4.3.29 Burner power control unit . 27
4.3.30 Flame monitoring . 27
5 Requirements to the design of electrical and electronic equipment for control and
protective systems . 28
6 Checking of safety requirements and/or measures . 29
7 User information . 31
7.1 Labelling . 31
7.2 Operating instructions . 32
7.2.1 General . 32
7.3 Description of the IThE . 32
7.4 Checking procedure . 33
7.5 Commissioning . 33
7.6 Shutdown procedure . 33
7.7 Maintenance procedure . 33
7.8 Documentation . 33
Annex A (normative) List of hazards (provisional) . 34
Annex B (informative) Typical examples of industrial thermoprocessing equipment, gas welding
equipment . 37
B.1 Classification . 37
Annex C (informative) Typical examples of piping diagrams . 38
Annex ZA (informative) Relationship between this European Standard and the essential
requirements of EU Directive 2006/42/EC aimed to be covered . 42
Annex ZB (informative) Relationship between this European Standard and the essential
requirements of EU Directive 2014/68/EU [2014 OJ L 189] (PED) aimed to be covered . 43
Bibliography . 44


3

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European foreword
This document (prEN 17942:2023) has been prepared by Technical Committee CEN/TC 121 “Welding
and allied processes”, the secretariat of which is held by DIN.
This document is currently submitted to the CEN Enquiry.
This document has been prepared under a Standardization Request given to CEN by the European
Commission and the European Free Trade Association, and supports essential requirements of EU
Directive(s) / Regulation(s).
For relationship with EU Directive(s) / Regulation(s), see informative Annexes ZA and ZB, which are
integral parts of this document.
4

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oSIST prEN 17942:2023
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Introduction
This document is a type-C standard, as defined in EN ISO 12100:2010.
The machinery affected and the extent to which hazards, hazardous situations and events are recorded
is referenced in the scope of application of this document.
If, in this type-C standard, provisions other than those in type-A or B standards are specified, the
provisions of the type-C standard apply to machinery designed and built in accordance with the
provisions of this type-C standard.
This document assumes that the equipment does not generate a potentially explosive atmosphere and is
located in an area with normal ventilation.
Even in the case of compliance with European product standards, e.g. EN 267, EN 12952-8, EN 12953-7
or EN 676, it is possible that the minimum safety requirements for IThE are not met. This document is
intended to be applied to Industrial Thermoprocessing Equipment with open firing oxy-fuel gas welding
equipment.
Thermoprocessing equipment (IThE) generally comprises the following components:
• gas distribution system, beginning in the direction of flow with the manually isolation main shut-off
valve at the inlet of the thermoprocessing equipment;
• burner, burner assembly and ignition system, open firing;
• safety control system (protective system).
5

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1 Scope
This document, together with EN 746-1:1997+A1:2009, EN 746-2:2010 and ISO 13577-4:2014, specifies
the safety requirements for industrial thermoprocessing equipment “Open firing oxy-fuel gas welding
equipment”, as well as the relevant gas distribution and protective systems. (Industrial thermoprocessing
equipment is referred below as “IThE”).
This document applies to IThE supplied with fuel gases.
This document covers the significant hazards, hazardous situations and events listed in Annex A for oxy-
fuel IThE, associated gas supply systems and protective systems on the basis that they are used as
intended and under the conditions specified by the manufacturer.
This document applies to:
• gas distribution system, beginning in the direction of flow with the manually isolation main shut-off
valve at the inlet of the thermoprocessing equipment;
• burner, burner assembly and ignition devices, open firing;
• safety control system (protective system).
This document is applicable to all types of combustion of fuel gases with atmospheric air, compressed air
or oxygen.
This document also includes necessary requirements for user information.
This document does not apply to manual burners, systems for flame spraying and micro soldering
torches.
This document does not apply to systems for welding, cutting and associated processes using plasma and
laser technology. This document does not cover the hazards arising as a result of the release of flammable
substances from the products processed in the IThE.
This document is not applicable to electrical wiring and heavy-current wiring connected upstream of the
IThE control cabinet/control panel/protective system.
Noise and optical radiation can cause significant hazards when using gas welding equipment. These are
not covered in this document.
This document is not applicable to oxy-fuel IThE, associated gas supply systems and protective systems
manufactured before the date of publication of this document in the Official Journal of the EU.
6

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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.
CEN/TR 13259:2013, Gas welding equipment — Industrial manual and machine blowpipes for flame
heating, flame brazing and allied processes
DIN 32509:2009-04, Hand-operated shut-off valves for welding, cutting and allied processes — Type of
construction, safety requirements, tests
EN 88-1:2011+A1:2016, Pressure regulators and associated safety devices for gas appliances — Part 1:
Pressure regulators for inlet pressures up to and including 50 kPa
EN 88-2:2007, Pressure regulators and associated safety devices for gas appliances — Part 2: Pressure
regulators for inlet pressures above 500 mbar up to and including 5 bar
EN 88-3:2022, Safety and control devices for gas burners and gas burning appliances — Part 3: Pressure
and/or flow rate regulators for inlet pressures up to and including 500 kPa, electronic types
EN 125:2010+A1:2015, Flame supervision devices for gas burning appliances — Thermoelectric flame
supervision devices
EN 161:2011+A3:2013, Automatic shut-off valves for gas burners and gas appliances
EN 298:2012, Automatic burner control systems for burners and appliances burning gaseous or liquid fuels
EN 331:2015, Manually operated ball valves and closed bottom taper plug valves for gas installations for
buildings
EN 334:2019, Gas pressure regulators for inlet pressure up to 10 MPa (100 bar)
EN 437:2021, Test gases — Test pressures — Appliance categories
EN 560:2018, Gas welding equipment — Hose connections for equipment for welding, cutting and allied
processes
EN 561:2002, Gas welding equipment — Quick-action coupling with shut-off valves for welding, cutting and
allied processes
EN 746-1:1997+A1:2009, Industrial thermoprocessing equipment — Part 1: Common safety requirements
for industrial thermoprocessing equipment
EN 746-2:2010, Industrial thermoprocessing equipment — Part 2: Safety requirements for combustion and
fuel handling systems
EN 1256:2006, Gas welding equipment — Specification for hose assemblies for equipment for welding,
cutting and allied processes
EN 1643:2014, Safety and control devices for gas burners and gas burning appliances — Valve proving
systems for automatic shut-off valves
EN 1854:2010, Pressure sensing devices for gas burners and gas burning appliances
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EN 60079-29-1:2016, Explosive atmospheres — Part 29-1: Gas detectors — Performance requirements of
detectors for flammable gases (IEC 60079-29-1:2016, modified)
EN 60204-1:2018, Safety of machinery — Electrical equipment of machines — Part 1: General
requirements (IEC 60204-1:2016, modified)
1
EN 61439-3:2012, Low-voltage switchgear and controlgear assemblies — Part 3: Distribution boards
intended to be operated by ordinary persons (DBO) (IEC 61439-3:2012)
EN 61439-4:2013, Low-voltage switchgear and controlgear assemblies — Part 4: Particular requirements
for assemblies for construction sites (ACS) (IEC 61439-4:2012)
EN 61439-5:2015, Low-voltage switchgear and controlgear assemblies — Part 5: Assemblies for power
distribution in public networks (IEC 61439-5:2014 + Cor.:2015)
EN 61439-6:2012, Low-voltage switchgear and controlgear assemblies — Part 6: Busbar trunking systems
(busways) (IEC 61439-6:2012)
EN 61508-1:2010, Functional safety of electrical/electronic/programmable electronic safety-related
systems — Part 1: General requirements (IEC 61508-1:2010)
EN 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 61508-2:2010)
EN 61508-3:2010, Functional safety of electrical/electronic/programmable electronic safety-related
systems — Part 3: Software requirements (IEC 61508-3:2010)
EN 61508-4:2010, Functional safety of electrical/electronic/programmable electronic safety-related
systems — Part 4: Definitions and abbreviations (IEC 61508-4:2010)
EN 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 61508-5:2010)
EN 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 61508-6:2010)
EN 61508-7:2010, Functional safety of electrical/electronic/programmable electronic safety-related
systems — Part 7: Overview of techniques and measures (IEC 61508-7:2010)
2
EN 61511-1:2017, Functional safety — Safety instrumented systems for the process industry sector —
Part 1: Framework, definitions, system, hardware and application programming Requirements
(IEC 61511-1:2016)
EN 61511-2:2017, Functional safety — Safety instrumented systems for the process industry sector —
Part 2: Guidelines for the application of IEC 61511-1 (IEC 61511-2:2016)
EN 61511-3:2017, Functional safety — Safety instrumented systems for the process industry sector —
Part 3: Guidance for the determination of the required safety integrity levels (IEC 61511-3:2016)

1
Document impacted by AC:2019.
2
Document impacted by A1:2017.
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3
EN 62061:2005, Safety of machinery — Functional safety of safety-related electrical, electronic and
programmable electronic control systems (IEC 62061:2005)
EN IEC 61439-1:2021, Low-voltage switchgear and controlgear assemblies — Part 1: General rules
(IEC 61439-1:2020)
EN IEC 61439-2:2021, Low-voltage switchgear and controlgear assemblies — Part 2: Power switchgear
and controlgear assemblies (IEC 61439-2:2020)
EN IEC/IEEE 82079-1:2020, Preparation of information for use (instructions for use) of products — Part 1:
Principles and general requirements (IEC/IEEE 82079-1:2019)
4
EN ISO 2503:2009, Gas welding equipment — Pressure regulators and pressure regulators with flow-
metering devices for gas cylinders used in welding, cutting and allied processes up to 300 bar (30 MPa)
(ISO 2503:2009)
EN ISO 3821:2019, Gas welding equipment — Rubber hoses for welding, cutting and allied processes
(ISO 3821:2019)
5
EN ISO 4126-1:2013, Safety devices for protection against excessive pressure — Part 1: Safety valves
(ISO 4126-1:2013)
EN ISO 5171:2019, Gas welding equipment — Pressure gauges used in welding, cutting and allied processes
(ISO 5171)
6
EN ISO 5172:2006, Gas welding equipment — Blowpipes for gas welding, heating and cutting —
Specifications and tests (ISO 5172:2006)
EN ISO 5175-1:2017, Gas welding equipment — Safety devices — Part 1: Devices incorporating a flame
(flashback) arrestor (ISO 5175-1:2017)
EN ISO 5175-2:2017, Gas welding equipment — Safety devices — Part 2: Devices not incorporating a flame
(flashback) arrestor (ISO 5175-2:2017, Corrected version 2019-01)
7
EN ISO 7291:2010, Gas welding equipment — Pressure regulators for manifold systems used in welding,
cutting and allied processes up to 30 MPa (300 bar) (ISO 7291:2010)
EN ISO 9012:2011, Gas welding equipment — Air-aspirated hand blowpipes — Specifications and tests
(ISO 9012:2008)
EN ISO 9090:2019, Gas tightness of equipment for gas welding and allied processes (ISO 9090:2019)
8
EN ISO 9539:2010, Gas welding equipment — Materials for equipment used in gas welding, cutting and
allied processes (ISO 9539:2010)
EN ISO 9606-1:2017, Qualification testing of welders — Fusion welding — Part 1: Steels (ISO 9606-1:2012
including Cor 1:2012 and Cor 2:2013)

3
Document impacted by Cor.:2010, A1:2013 and A2:2015.
4
Document impacted by A1:2015.
5
Document impacted by A1:2016.
6
Document impacted by A1:2012 and A2:2015.
7
Document impacted by A1:2015.
8
Document impacted by A1:2013.
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EN ISO 11114-1:2020, Gas cylinders — Compatibility of cylinder and valve materials with gas contents —
Part 1: Metallic materials (ISO 11114-1:2020)
EN ISO 11114-2:2021, Gas cylinders — Compatibility of cylinder and valve materials with gas contents —
Part 2: Non-metallic materials (ISO 11114-2:2021)
EN ISO 12100:2010, Safety of machinery — General principles for design — Risk assessment and risk
reduction (ISO 12100:2010)
EN ISO 13585:2012, Brazing — Qualification test of brazers and brazing operators (ISO 13585:2012)
EN ISO 13849-1:2015, Sicherheit von Maschinen — Sicherheitsbezogene Teile von Steuerungen — Teil 1:
Allgemeine Gestaltungsleitsätze (ISO 13849-1:2015)
EN ISO 13849-2:2012, Safety of machinery — Safety-related parts of control systems — Part 2: Validation
(ISO 13849-2:2012)
EN ISO 14114:2018, Gas welding equipment — Acetylene manifold systems for welding, cutting and allied
processes — General requirements (ISO 14114:2017)
EN ISO 14731:2019, Welding coordination — Tasks and responsibilities (ISO 14731:2019)
EN ISO 15296:2018, Gas welding equipment — Vocabulary (ISO 15296:2017)
ISO 13574:2015, Industrial furnaces and associated processing equipment — Vocabulary
ISO 13577-4:2014, Industrial furnace and associated processing equipment — Safety — Part 4: Protective
systems
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3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 13574:2015,
EN ISO 15296:2018, EN 746-1:1997+A1:2009, EN 746-2:2010, CEN/TR 13259:2013 and the following
apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
• ISO Online browsing platform: available at https://www.iso.org/obp
• IEC Electropedia: available at http://www.electropedia.org/
3.1
open firing oxy-fuel gas welding equipment
equipment in accordance with EN ISO 5172:2006, EN ISO 9012:2011 or CEN/TR 13259:2013 for heating
and processing materials or workpieces via open firing burning using a fuel gas/oxygen mixture or fuel
gas/air mixture
Note 1 to entry: The addition of “open firing” is dropped in the following part of the document.
3.2
automated industrial thermoprocessing equipment
IThE
IThE where all thermal, mechanical and control-related processes can be controlled via PLC, NC or CNC
Note 1 to entry: The entire process is self-monitoring. The thermal power of the IThE can be controlled
automatically or manually. Otherwise, the IThE includes the majority of gas distribution systems, gas welding
equipment, ignition devices and safety-related control systems listed in the scope of application
3.3
gas warning device
device that uses sensors to detect and indicate the presence of a fuel gas/air mixture and initiates a safety
shutdown at or before 25 % of the lower explosion limit (LEL)
3.4
air/fuel gas ratio; oxygen/fuel gas ratio
ratio of the masses/flow rates of combustion air/oxygen and fuel gas
3.5
safety shut-down
establishing of a safe state of the IThE in the shortest possible time without compromising the safety of
the IThE or the environment
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4 Safety requirements, measures and ascertaining compliance
4.1 General
EN 746-1:1997+A1:2009 provides the general safety requirements common to automated industrial
thermoprocessing equipme
...