SIST EN ISO 21904-1:2020
(Main)Health and safety in welding and allied processes - Equipment for capture and separation of welding fume - Part 1: General requirements (ISO 21904-1:2020)
Health and safety in welding and allied processes - Equipment for capture and separation of welding fume - Part 1: General requirements (ISO 21904-1:2020)
ISO 21904-1 defines the general requirements for ventilation equipment used to capture and separate fumes generated by welding and allied processes, e.g. arc welding and thermal cutting.This document also specifies the test data to be marked on the capture devices.It applies to the design and manufacture of parts of the equipment including hoods for welding, ducting, filter units, air movers, systems that inform of unsafe operation and workplace practices to ensure safe working with regard to exposure.Significant hazards are listed in Clause 4. It does not cover electrical, mechanical and pneumatic hazards.This document is applicable to:- local exhaust ventilation systems (LEV) excluding draught tables;- mobile and stationary equipment;- separation equipment used for welding and allied processes;This document is not applicable to:- general ventilation, air make up or air movement systems;- air conditioning systems;- grinding dust.This document applies to systems designed and manufactured after its publication.
Arbeits- und Gesundheitsschutz beim Schweißen und bei verwandten Verfahren - Einrichtungen zum Erfassen und Abscheiden von Schweißrauch - Teil 1: Allgemeine Anforderungen (ISO 21904-1:2020)
Dieses Dokument legt die allgemeinen Anforderungen an Lüftungsanlagen zur Erfassung und Abscheidung der beim Schweißen und bei verwandten Prozessen, z. B. Lichtbogenschweißen und Brennschneiden, erzeugten Rauchemissionen fest.
Dieses Dokument legt auch die Prüfdaten fest, die auf den Erfassungseinrichtungen anzubringen sind.
Es gilt für die Konstruktion und Herstellung von Teilen der Anlage, einschließlich Schweißrauchabzugshauben, Lüftungskanäle, Filtereinheiten, Luftbewegungs¬einrichtungen und Warnsysteme zur Anzeige eines nicht sicheren Betriebs und eines gefährlichen Arbeitsplatzes, um ein sicheres Arbeiten bezüglich der Emissionsexposition sicherzustellen.
In Abschnitt 4 sind wesentliche Gefährdungen aufgelistet. Er behandelt keine elektrischen, mechanischen und pneumatischen Gefährdungen.
Dieses Dokument gilt für:
- örtliche Absaugungssysteme (LEV), außer abgesaugte Schweißtische;
- bewegliche und stationäre Anlagen;
- Abscheideeinrichtungen für Schweißen und verwandte Prozesse.
Dieses Dokument gilt nicht für:
- allgemeine lüftungstechnische Anlagen, Luftaufbereiter oder Luftbewegungssysteme;
- Klimaanlagen;
- Schleifstaub.
Dieses Dokument gilt für Systeme, die nach Veröffentlichung dieser Norm konstruiert und hergestellt wurden.
ANMERKUNG Spezifische Sicherheitsanforderungen für Maschinen zum thermischen Trennen werden in ISO 17916 festgelegt.
Hygiène et sécurité en soudage et techniques connexes - Equipements de captage et de filtration des fumées - Partie 1: Exigences générales (ISO 21904-1:2020)
Le présent document définit les exigences générales relatives à l'équipement de ventilation servant pour le captage et la filtration de fumées produites par le soudage et les techniques connexes par exemple, le soudage à l'arc et le procédé de coupage thermique.
Le présent document spécifie également les données d'essai qui doivent être marquées sur les dispositifs de captage.
Il s'applique à la conception et à la fabrication des pièces de l'équipement, notamment les bouches d'aspiration pour le soudage, les conduits, les unités de filtration, les dispositifs d'entraînement de l'air et les systèmes qui signalent un fonctionnement dangereux, et aux pratiques sur le lieu de travail visant à assurer un travail en toute sécurité en matière d'exposition.
Les phénomènes dangereux significatifs sont énumérés dans l'Article 4. Le présent document ne traite pas des phénomènes dangereux électriques, mécaniques et pneumatiques.
Le présent document est applicable:
— aux systèmes de ventilation par extraction localisée (LEV), à l'exclusion des tables aspirantes;
— aux équipements mobiles et fixes;
— équipement de filtration utilisé pour le soudage et les techniques connexes;
Le présent document ne s'applique pas:
— aux systèmes de ventilation générale, d'air d'appoint ou de déplacement d'air;
— aux systèmes de conditionnement d'air;
— à la poussière de meulage.
Le présent document est applicable aux systèmes fabriqués après sa date de publication.
NOTE Les spécifications de sécurité spécifiques pour les machines de coupage thermique sont définies dans la norme ISO 17916.
Zdravje in varnost pri varjenju in sorodnih postopkih - Oprema za zajem in ločevanje varilnega dima - 1. del: Splošne zahteve (ISO 21904-1:2020)
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
SIST EN ISO 21904-1:2020
01-maj-2020
Nadomešča:
SIST EN ISO 15012-4:2016
Zdravje in varnost pri varjenju in sorodnih postopkih - Oprema za zajem in
ločevanje varilnega dima - 1. del: Splošne zahteve (ISO 21904-1:2020)
Health and safety in welding and allied processes - Equipment for capture and
separation of welding fume - Part 1: General requirements (ISO 21904-1:2020)
Arbeits- und Gesundheitsschutz beim Schweißen und bei verwandten Verfahren -
Einrichtungen zum Erfassen und Abscheiden von Schweißrauch - Teil 1: Allgemeine
Anforderungen (ISO 21904-1:2020)
Hygiène et sécurité en soudage et techniques connexes - Equipements de captage et de
filtration des fumées - Partie 1: Exigences générales (ISO 21904-1:2020)
Ta slovenski standard je istoveten z: EN ISO 21904-1:2020
ICS:
13.040.40 Emisije nepremičnih virov Stationary source emissions
13.100 Varnost pri delu. Industrijska Occupational safety.
higiena Industrial hygiene
25.160.30 Varilna oprema Welding equipment
SIST EN ISO 21904-1:2020 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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SIST EN ISO 21904-1:2020
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SIST EN ISO 21904-1:2020
EN ISO 21904-1
EUROPEAN STANDARD
NORME EUROPÉENNE
March 2020
EUROPÄISCHE NORM
ICS 25.160.01; 13.100 Supersedes EN ISO 15012-4:2016
English Version
Health and safety in welding and allied processes -
Equipment for capture and separation of welding fume -
Part 1: General requirements (ISO 21904-1:2020)
Hygiène et sécurité en soudage et techniques connexes Arbeits- und Gesundheitsschutz beim Schweißen und
- Equipements de captage et de filtration des fumées - bei verwandten Verfahren - Einrichtungen zum
Partie 1: Exigences générales (ISO 21904-1:2020) Erfassen und Abscheiden von Schweißrauch - Teil 1:
Allgemeine Anforderungen (ISO 21904-1:2020)
This European Standard was approved by CEN on 31 January 2020.
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, Turkey 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
© 2020 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 21904-1:2020 E
worldwide for CEN national Members.
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SIST EN ISO 21904-1:2020
EN ISO 21904-1:2020 (E)
Contents Page
European foreword . 3
Annex ZA (informative) Relationship between this European Standard and the Essential
Requirements of EU Directive 2006/42/EC aimed to be covered . 4
2
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SIST EN ISO 21904-1:2020
EN ISO 21904-1:2020 (E)
European foreword
This document (EN ISO 21904-1:2020) has been prepared by Technical Committee ISO/TC 44 "Welding
and allied processes" in collaboration with Technical Committee CEN/TC 121 “Welding and allied
processes” 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 September 2020, and conflicting national standards
shall be withdrawn at the latest by September 2020.
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.
This document supersedes EN ISO 15012-4:2016.
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 the relationship with EU Directive(s) see informative Annex ZA, which is an integral part of this
document.
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, Turkey and the
United Kingdom.
Endorsement notice
The text of ISO 21904-1:2020 has been approved by CEN as EN ISO 21904-1:2020 without any
modification.
3
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SIST EN ISO 21904-1:2020
EN ISO 21904-1:2020 (E)
Annex ZA
(informative)
Relationship between this European Standard and the Essential
Requirements of EU Directive 2006/42/EC aimed to be covered
This European Standard has been prepared under a Commission’s standardization request M/396
(Machinery) to provide one voluntary means of conforming to essential requirements of 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).
Once this standard is cited in the Official Journal of the European Union under that Directive,
compliance with the normative clauses of this standard given in Table ZA.1 confers, within the limits of
the scope of this standard, a presumption of conformity with the corresponding essential requirements
of that EU Directive 2006/42/EC, and associated EFTA regulations.
Table ZA.1 — Correspondence between this European Standard and EU Directive 2006/42/EC
Essential Requirements of EU Clause(s)/subclause(s) Remarks/Notes
Directive 2006/42/EC
of this EN
1.5.13 5.1, 5.2, 5.3, 5.4, 6, 7
WARNING 1 — Presumption of conformity stays valid only as long as a reference to this European
Standard is maintained in the list published in the Official Journal of the European Union. Users of this
standard should consult frequently the latest list published in the Official Journal of the European
Union.
WARNING 2 — Other Union legislation may be applicable to the product(s) falling within the scope of
this standard.
4
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SIST EN ISO 21904-1:2020
INTERNATIONAL ISO
STANDARD 21904-1
First edition
2020-02
Health and safety in welding and allied
processes — Equipment for capture
and separation of welding fume —
Part 1:
General requirements
Hygiène et sécurité en soudage et techniques connexes —
Equipements de captage et de filtration des fumées —
Partie 1: Exigences générales
Reference number
ISO 21904-1:2020(E)
©
ISO 2020
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SIST EN ISO 21904-1:2020
ISO 21904-1:2020(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2020
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
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Fax: +41 22 749 09 47
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii © ISO 2020 – All rights reserved
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SIST EN ISO 21904-1:2020
ISO 21904-1:2020(E)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 2
4 Significant hazards . 4
5 Requirements and verifications . 4
5.1 General . 4
5.2 Extraction devices . 7
5.3 Ducting properties .13
5.4 Filters, related components and handling .15
6 Instructions for use .19
6.1 General .19
6.2 Extraction devices .19
6.2.1 Captor hoods and nozzles .19
6.2.2 On-torch extraction systems .20
7 Marking .20
7.1 General marking .20
7.2 Marking of separation efficiency .21
7.3 Marking of captor hoods and nozzles .21
7.4 Marking of on-torch extraction systems .21
Annex A (informative) Malfunctions and determination of minimum airflow .23
Annex B (normative) Label for welding fume separation equipment .24
Bibliography .25
© ISO 2020 – All rights reserved iii
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SIST EN ISO 21904-1:2020
ISO 21904-1:2020(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/d irectives).
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/p atents).
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/f oreword. html.
This document was prepared by Technical Committee ISO/TC 44, Welding and allied processes,
Subcommittee SC 9, Health and safety.
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.
Official interpretations of ISO/TC 44 documents, where they exist, are available from this page:
https://committee. iso. org/sites/ tc 44/ home/interpretation . html.
A list of all parts in the ISO 21904 series can be found on the ISO website.
This first edition cancels and replaces ISO 15012-4.
iv © ISO 2020 – All rights reserved
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SIST EN ISO 21904-1:2020
ISO 21904-1:2020(E)
Introduction
Welding and allied processes generate fumes and gases which, if inhaled, can be harmful to human
health. Therefore, control of the fumes and gases generated is to be exercised to minimize worker
exposure.
The most effective method of control is to capture the fumes and gases close to their source before they
enter a worker’s breathing zone or the general workplace environment.
Ventilation equipment used to capture the fumes and gases is to be fit for purpose because inefficient
capture can result in high exposure and can be detrimental to workers’ health. Therefore, it is important
that it adheres to defined manufacturing, materials and design requirements and gives warning of
malfunction.
This document is a type-C standard as stated in ISO 12100.
This document is of relevance, in particular, for the following stakeholder groups representing the
market players with regard to machinery safety:
— machine manufacturers (small, medium and large enterprises);
— health and safety bodies (regulators, accident prevention organisations, market surveillance etc.);
Others can be affected by the level of machinery safety achieved with the means of the document by the
above-mentioned stakeholder groups:
— machine users/employers (small, medium and large enterprises);
— machine users/employees (e.g. trade unions, organizations for people with special needs);
— service providers, e. g. for maintenance (small, medium and large enterprises);
— consumers (in case of machinery intended for use by consumers).
The above-mentioned stakeholder groups have been given the possibility to participate at the drafting
process of this document.
In addition, this document is intended for standardization bodies elaborating type-C standards.
The requirements of this document can be supplemented or modified by a type-C standard.
For machines which are covered by the scope of a type-C standard and which have been designed and
built according to the requirements of that standard, the requirements of that type-C standard take
precedence.
© ISO 2020 – All rights reserved v
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SIST EN ISO 21904-1:2020
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SIST EN ISO 21904-1:2020
INTERNATIONAL STANDARD ISO 21904-1:2020(E)
Health and safety in welding and allied processes —
Equipment for capture and separation of welding fume —
Part 1:
General requirements
1 Scope
This document defines the general requirements for ventilation equipment used to capture and
separate fumes generated by welding and allied processes, e.g. arc welding and thermal cutting.
This document also specifies the test data to be marked on the capture devices.
It applies to the design and manufacture of parts of the equipment including hoods for welding, ducting,
filter units, air movers, systems that inform of unsafe operation and workplace practices to ensure safe
working with regard to exposure.
Significant hazards are listed in Clause 4. It does not cover electrical, mechanical and pneumatic
hazards.
This document is applicable to:
— local exhaust ventilation systems (LEV) excluding draught tables;
— mobile and stationary equipment;
— separation equipment used for welding and allied processes;
This document is not applicable to:
— general ventilation, air make up or air movement systems;
— air conditioning systems;
— grinding dust.
This document applies to systems designed and manufactured after its publication.
NOTE Specific safety requirements for thermal cutting machines are defined in ISO 17916.
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 12100:2010, Safety of machinery — General principles for design — Risk assessment and risk reduction
ISO 13849-1:2015, Safety of machinery — Safety-related parts of control systems — Part 1: General
principles for design
ISO 21904-2:2020, Health and safety in welding and allied processes — Equipment for capture and
separation of welding fume — Part 2: Requirements for testing and marking of separation efficiency
© ISO 2020 – All rights reserved 1
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SIST EN ISO 21904-1:2020
ISO 21904-1:2020(E)
ISO 21904-4:2020, Health and safety in welding and allied processes — Requirements, testing and marking
of equipment for air filtration — Part 4: Determination of the minimum air volume flow rate of captor
hoods and nozzles
IEC 60204-1:2005, Safety of machinery — Electrical equipment of machines — Part 1: General requirements
IEC 60335-2-69:2012, Household and similar electrical appliances — Safety — Part 2-69: Particular
requirements for wet and dry vacuum cleaners, including power brush, for commercial use
IEC 60695-2-12:2010+A1: 2014, Fire hazard testing — Part 2-12: Glowing/hot-wire based test methods —
Glow-wire flammability index (GWFI) test method for materials
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 12100:2010 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
welding fume separation equipment
air filtration equipment, the purpose of which is to separate particles generated by welding and allied
processes from workplace atmosphere
Note 1 to entry: Some separation equipment is designed to also remove gases generated by welding, but the
ISO 21904 series does not address the efficiency of gas separation.
3.2
filter cleaning system
system designed to clean the filter of welding fume separation equipment (3.1) in order to restore the air
flow rate through the filter when it is reduced by an accumulation of welding fume (3.13) particles
3.3
on-line filter cleaning system
filter cleaning system, either automatically or manually initiated, operating while welding fume
separation equipment (3.1) is running
3.4
off-line filter cleaning system
filter cleaning system, either automatically or manually initiated, operating after the air mover of the
filtration equipment is switched off
3.5
separation efficiency by mass
ratio of the mass of particles retained by welding fume separation equipment (3.1) to the mass of particles
entering the equipment during a given period
Note 1 to entry: General information on test methods for determination of separation efficiency is described in
EN 1093-6 and EN 1093-7.
3.6
local exhaust ventilation
LEV
use of extraction to remove contaminated air at or near to its source
2 © ISO 2020 – All rights reserved
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SIST EN ISO 21904-1:2020
ISO 21904-1:2020(E)
3.7
filter protector
device normally positioned at the intake of the welding fume separation equipment (3.1), used to
minimize the possibility of damaging impacts of sparks or large particles on filter media
Note 1 to entry: Filter media can also be protected against sparks and large particles by the internal design of the
welding fume separation equipment.
Note 2 to entry: Examples of filter protectors are cyclones, spin separators, baffles or sieves. A filter protector
may be designed to also protect against flame damage.
3.8
on-torch extraction device
on-gun extraction device
equipment, integrated or attached, on torch used for capturing welding fume (3.13), when connected to
an extraction source
Note 1 to entry: Due to the state of the art, on-torch extraction devices for TIG welding are not covered by this
definition.
Note 2 to entry: For an overview of the different extraction devices, see Figure 1.
Dimensions in metres
Key
3 3
1 on-torch extraction (3.8), 50 m /h to 100 m /h, 5 kPa to 18 kPa
3 3
2 high vacuum extraction (3.9), 100 m /h to 150 m /h, 5 kPa to 10 kPa
3 3
3 low vacuum extraction (3.9), 700 m /h to 1500 m /h, 800 Pa to 2 000 Pa
Figure 1 — Overview of extraction devices and common air volume flow rates and pressure
3.9
captor hood
captor nozzle
equipment, movable or static, used for capturing welding fume (3.13), when connected to an
extraction source
Note 1 to entry: For an overview of the different extraction devices, see Figure 1.
3.10
receiving hood
canopy
equipment, movable or static, normally positioned above a hot process, where the contaminated air is
propelled into it by process-induced air movement
© ISO 2020 – All rights reserved 3
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SIST EN ISO 21904-1:2020
ISO 21904-1:2020(E)
3.11
enclosure
chamber
fully or partially enclosed space where the process takes place, designed to contain and prevent the
escape of hazardous substances into the workshop air
3.12
suction equipment
unit with air mover and with or without a filter
3.13
welding fume
airborne particles typically with diameter smaller than 1 µm generated by welding and allied processes
3.14
minimum air volume flow rate
air volume flow rate required for acceptable capture of welding fume (3.13)
Note 1 to entry: The minimum air volume flow rate depends on the type and the geometric dimensions of the
capture device and the test positions selected to demonstrate the extent of the capture zone (see 7.3).
3.15
suction field
volume around a capture device, in which the air velocity required to capture welding fume (3.13) is
exceeded
4 Significant hazards
Exposure to welding fumes and gases generated by welding and allied processes can be detrimental to
health. Control of exposure can usually be achieved using ventilation equipment but any failure of this
equipment, such as poor design and the use of parts made of unsuitable materials, can result in reduced
extraction efficiency and hence over exposure and ill health.
Common health effects include respiratory disease, but exposure to carcinogenic substances during the
welding can occur and shall be considered.
The requirements of the ventilation equipment are dependent on the level of control necessary.
5 Requirements and verifications
5.1 General
The general requirements and corresponding verifications are given in Table 1.
4 © ISO 2020 – All rights reserved
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SIST EN ISO 21904-1:2020
ISO 21904-1:2020(E)
© ISO 2020 – All rights reserved 5
Table 1 — General requirements and verifications
Requirement Verification
1.1 Requirements for all Machinery shall comply with the safety requirements and/or protective/
equipment risk reduction measures in Clause 5. In addition, the machine shall be
designed according to the principles of ISO 12100:2010 for relevant but not
significant hazards which are not dealt with by this document.
All parts and materials used in the manufacture of welding fume ventila- Verification shall be performed by examining the
tion equipment shall withstand the conditions (thermal, mechanical, UV ra- manufacturer’s datasheets, the instruction manual,
diation) present in the environment in which they are intended to be used. and by referring to the manufacturer's long-term
experience with respective devices.
Equipment used for capturing of welding fume shall be fitted with indi- Conformity shall be checked by visual and/or audible
cators and control units showing correct operation or malfunction of the inspection.
device, as malfunctions can cause hazardous operation conditions for the
user. Malfunction of equipment shall be indicated by a clear visual or acous-
tic warning signal. Two types of malfunctions are possible and are shown in
Annex A together with their most common causes.
Visual warning signals shall work with a pulse frequency between 2 Hz and
0,2 Hz, emitting yellow or yellow-orange light. Visible warning signals shall
be installed inside or nearby the working area of welders in order to be
recognized when the light is on.
NOTE EN 842 provides additional guidance for visual danger signals. This
document can also be part of national legislation.
If an acoustic warning device is installed, it shall work within an audio-fre-
quency between 500 Hz and 3 000 Hz and have a pulse time between 0,5 s
and 5 s. The A-weighted sound pressure level shall be between 8 dB and
20 dB higher than the 1 m-surface sound pressure level of the welding fume
separation equipment.
Signals/indicators for normal operation
— For LEV: Proper operation of a LEV shall be indicated by a control lamp
emitting green light.
— For dampers on devices for capturing: Capture equipment fitted with
a manual shut off damper, the handle shall be aligned with the damper
position. For automatic dampers, the position shall be indicated clearly
visible to the user as open or closed.
Warning signals for malfunction Conformity shall be checked by simulating a malfunc-
tion in order to test the function of the warning signal.
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SIST EN ISO 21904-1:2020
ISO 21904-1:2020(E)
6 © ISO 2020 – All rights reserved
Table 1 (continued)
Requirement Verification
— Separation equipment shall be fitted with a device that indicates that
the filter needs service (either cleaning or replacement). When any
malfunction exists, the control lamp shall not emit green light and the
warning signals shall be active.
NOTE There is currently no reliable system for monitoring the filter efficiency.
It is there
...
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Health and safety in welding and allied processes - Equipment for capture and
separation of welding fume - Part 1: General requirements (ISO/DIS 21904-1:2019)
Arbeits- und Gesundheitsschutz beim Schweißen und bei verwandten Verfahren -
Einrichtungen zum Erfassen und Abscheiden von Schweißrauch - Teil 1: Allgemeine
Anforderungen (ISO/DIS 21904-1:2019)
Hygiène et sécurité en soudage et techniques connexes - Exigences, essais et
marquage des équipements de filtration d'air - Partie 1: Exigences générales (ISO/DIS
21904-1:2019)
Ta slovenski standard je istoveten z: prEN ISO 21904-1
ICS:
13.040.40 (PLVLMHQHSUHPLþQLKYLURY Stationary source emissions
13.100 Varnost pri delu. Industrijska Occupational safety.
higiena Industrial hygiene
25.160.30 Varilna oprema Welding equipment
oSIST prEN ISO 21904-1:2019 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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oSIST prEN ISO 21904-1:2019
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oSIST prEN ISO 21904-1:2019
DRAFT INTERNATIONAL STANDARD
ISO/DIS 21904-1
ISO/TC 44/SC 9 Secretariat: BSI
Voting begins on: Voting terminates on:
2019-01-29 2019-04-23
Health and safety in welding and allied processes —
Equipment for capture and separation of welding fume —
Part 1:
General requirements
Hygiène et sécurité en soudage et techniques connexes — Exigences, essais et marquage des équipements
de filtration d'air —
Partie 1: Exigences générales
ICS: 13.100; 25.160.01
THIS DOCUMENT IS A DRAFT CIRCULATED
This document is circulated as received from the committee secretariat.
FOR COMMENT AND APPROVAL. IT IS
THEREFORE SUBJECT TO CHANGE AND MAY
NOT BE REFERRED TO AS AN INTERNATIONAL
STANDARD UNTIL PUBLISHED AS SUCH.
IN ADDITION TO THEIR EVALUATION AS
ISO/CEN PARALLEL PROCESSING
BEING ACCEPTABLE FOR INDUSTRIAL,
TECHNOLOGICAL, COMMERCIAL AND
USER PURPOSES, DRAFT INTERNATIONAL
STANDARDS MAY ON OCCASION HAVE TO
BE CONSIDERED IN THE LIGHT OF THEIR
POTENTIAL TO BECOME STANDARDS TO
WHICH REFERENCE MAY BE MADE IN
Reference number
NATIONAL REGULATIONS.
ISO/DIS 21904-1:2019(E)
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. ISO 2019
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ISO/DIS 21904-1:2019(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2019
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
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ii © ISO 2019 – All rights reserved
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Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 2
4 Significant hazards . 4
5 Requirements and verifications . 4
5.1 General . 4
5.2 Extraction devices . 7
5.3 Ducting properties .13
5.4 Filters , related components and handling .15
6 Instructions for use .18
6.1 General .18
6.2 Extraction devices .18
6.2.1 Captor hoods and nozzles .18
6.2.2 On-torch extraction systems .19
7 Marking .19
7.1 General marking .19
7.2 Marking of separation efficiency .19
7.3 Marking of captor hoods and nozzles .19
7.4 Marking of on-torch extraction systems .20
Annex A (informative) Malfunctions and determination of minimum airflow .21
Annex B (normative) Label for welding fume separation equipment .22
Annex ZA (informative) Relationship between this European Standard and the Essential
Requirements of EU Directive 2006/42/EC aimed to be covered .23
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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 on 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 the following
URL: www .iso .org/iso/foreword .html.
This document was prepared by Technical Committee ISO/TC 44, Welding and allied processes,
Subcommittee SC 9, Health and safety.
A list of all parts in the ISO 21904-series can be found on the ISO website.
Requests for official interpretations of any aspect of this document should be directed to the Secretariat
of ISO/TC 44/SC 9 via your national standards body. A complete listing of these bodies can be found at
www .iso .org.
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Introduction
Welding and allied processes generate fumes and gases which, if inhaled, can be harmful to human
health. Therefore, control of the fumes and gases generated is to be exercised to minimize worker
exposure.
The most effective method of control is to capture the fumes and gases close to their source before they
enter a worker’s breathing zone or the general workplace environment.
Ventilation equipment used to capture the fumes and gases is to be fit for purpose because inefficient
capture could result in high exposure and can be detrimental to workers’ health. It is important
therefore that it adheres to defined manufacturing, materials and design requirements and gives
warning of malfunction.
This part of ISO 21904 defines the general requirements that are necessary for ventilation equipment
to maintain exposure to fumes at acceptable levels.
This part of ISO 21904 is a type-B standard as stated in ISO 12100.
This part of ISO 21904 is of relevance, in particular, for the following stakeholder groups representing
the market players with regard to machinery safety:
— machine manufacturers (small, medium and large enterprises);
— health and safety bodies (regulators, accident prevention organizations, market surveillance, etc.).
Others can be affected by the level of machinery safety achieved with the means of this part of ISO 21904
by the above-mentioned stakeholder groups:
— machine users/employers (small, medium and large enterprises);
— machine users/employees (e.g. trade unions, organizations for people with special needs);
— service providers, e.g. for maintenance (small, medium and large enterprises);
— consumers (in case of machinery intended for use by consumers).
The above-mentioned stakeholder groups have been given the possibility to participate at the drafting
process of this part of ISO 21904.
In addition, this part of ISO 21904 is intended for standardization bodies elaborating type-C standards.
The requirements of this part of ISO 21904 can be supplemented or modified by a type-C standard.
For machines which are covered by the scope of a type-C standard and which have been designed and
built according to the requirements of that standard, the requirements of that type-C standard take
precedence.
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DRAFT INTERNATIONAL STANDARD ISO/DIS 21904-1:2019(E)
Health and safety in welding and allied processes —
Equipment for capture and separation of welding fume —
Part 1:
General requirements
1 Scope
This part of ISO 21904 defines the general requirements for ventilation equipment used to capture
and separate fumes generated by welding and allied processes e.g. arc welding and thermal cutting. It
applies to the design and manufacture of parts of the equipment including hoods for welding, ducting,
filter units, air movers, systems that inform of unsafe operation and workplace practices to ensure safe
working with regard to exposure.
Significant hazards are listed in Clause 4. It does not cover electrical, mechanical and pneumatic
hazards.
This part of ISO 21904 is applicable to the following:
— local exhaust ventilation systems (LEV) excluding draught tables;
— mobile and stationary equipment;
— separation equipment used for welding and allied processes;
This part of ISO 21904 is not applicable to the following:
— general ventilation, air make up or air movement systems;
— air conditioning systems;
— grinding dust.
This part of ISO 21904 also specifies the test data to be marked on the capture devices.
This part of ISO 21904 applies to systems designed and manufactured after its publication.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and are
indispensable for its application. For dated references, only the edition cited applies. For undated
references, the latest edition of the referenced document (including any amendments) applies.
ISO 12100:2010, Safety of machinery — General principles for design — Risk assessment and risk reduction
ISO 21904-2:2013, Health and safety in welding and allied processes — Equipment for capture and
separation of welding fume — Part 2: Requirements for testing and marking of separation efficiency
ISO 21904-4, Health and safety in welding and allied processes — Requirements, testing and marking of
equipment for air filtration — Part 4: Determination of the minimum air volume flow rate of captor hoods
and nozzles
IEC 60204-1:2005, Safety of machinery — Electrical equipment of machines — Part 1: General requirements
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IEC 60335-2-69, Household and similar electrical appliances — Safety — Part 2-69: Particular requirements
for wet and dry vacuum cleaners, including power brush, for commercial use
IEC 60695-2-12, Fire hazard testing — Part 2-12: Glowing/hot-wire based test methods — Glow-wire
flammability index (GWFI) test method for materials
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 12100 and ISO/TR 25901-2
and the following apply.
3.1
welding fume separation equipment
air filtration equipment, the purpose of which is to separate particles generated by welding and allied
processes from workplace atmosphere
Note 1 to entry: Some separation equipment is designed to also remove gases generated by welding, but this
series of standards does not address the efficiency of gas separation.
3.2
filter cleaning system
system designed to clean the filter of welding fume separation equipment in order to restore the air
flow rate through the filter when it is reduced by an accumulation of welding fume particles
3.3
on-line filter cleaning system
filter cleaning system operating while welding fume separation equipment is working
3.4
off-line filter cleaning system
filter cleaning system operating after the air mover of the filtration equipment is switched off
3.5
separation efficiency by mass
ratio of the mass of particles retained by welding fume separation equipment to the mass of particles
entering the equipment during a given period
Note 1 to entry: General information on test methods for determination of separation efficiency is described in
EN 1093-6 and EN 1093-7.
3.6
emission rate
mass of the particles emitted by the welding fume source per time
Note 1 to entry: Emission rate is expressed in milligrams per second.
3.7
local exhaust ventilation
LEV
use of extraction to remove contaminated air at or near to its source
3.8
filter protector
device normally positioned at the intake of the welding fume separation equipment, used to minimize
the possibility of damaging impacts of sparks or large particles on filter media
Note 1 to entry: Filter media can also be protected against sparks and large particles by the internal design of the
welding fume separation equipment.
Note 2 to entry: Examples of filter protectors are cyclones, spin separators, baffles or sieves. A filter protector
may be designed to also protect against flame damage.
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3.9 extraction device
3.9.1
on-torch extraction device
on-gun extraction device
equipment, integrated or attached, on torch used for capturing welding fume, when connected to an
extraction source
3.9.2
captor hood
captor nozzle
equipment, movable or static, used for capturing welding fume, when connected to an extraction source
3.9.3
receiving hood
canopy
equipment, movable or static, normally positioned above a hot process, where the contaminated air is
propelled into it by process-induced air movement
3.9.4
enclosure
chamber
fully or partially enclosed space where the process takes place, designed to contain and prevent the
escape of hazardous substances into the workshop air
Dimensions in meters
Key
3 3
1 low vacuum extraction, 700 m /h to 1000 m /h, 800 Pa to 2000 Pa
3 3
2 high vacuum extraction, 100 m /h to 150 m /h, 5 kPa to 10 kPa
3 3
3 on-gun extraction, 50 m /h to 100 m /h, 10 kPa to 18 kPa
Figure 1
3.10
suction equipment
unit with air mover and with or without a filter
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3.11
fume
airborne particles typically with diameter smaller than 1µm generated by thermal processes
3.12
minimum air volume flow rate
air volume flow rate required for acceptable capture of fume
Note 1 to entry: The minimum air volume flow rate depends on the type and the geometric dimensions of the
capture device and the test positions selected to demonstrate the extent of the capture zone (see 7.3).
3.13
suction field
the volume around a capture device, in which the air velocity required to capture welding fume is
exceeded
4 Significant hazards
Exposure to fumes and gases generated by welding and allied processes can be detrimental to health.
Control of exposure can usually be achieved using ventilation equipment but any failure of this
equipment, such as poor design and the use of parts made of unsuitable materials, can result in reduced
extraction efficiency and hence over exposure and ill health.
Common health effects include respiratory disease, but exposure to carcinogenic substances during the
welding of alloyed materials can occur and shall be considered.
The requirements of the ventilation equipment are dependent on the level of control necessary.
5 Requirements and verifications
5.1 General
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Requirement Verification
1.1 Machinery shall comply with the safety requirements and/or protective/risk
reduction measures in Clause 5. In addition, the machine shall be designed
R e qu i r em en t s f o r a l l
according to the principles of ISO 12100 for relevant but not significant hazards
equipment
which are not dealt with by this part of ISO 21904.
All parts and materials used in the manufacture of fume ventilation equipment Verification shall be performed by examining the
shall withstand the conditions (thermal, mechanical, UV radiation) present manufacturer’s datasheets, the instruction manual, and
in the environment in which they are intended to be used. by referring to the manufacturer's long-term experience
with respective devices.
Equipment used for capturing of fume shall be fitted with indicators and control Conformity shall be checked by visual and/or audible
units showing correct operation or malfunction of the device, as malfunctions inspection.
can cause hazardous operation conditions for the user. Malfunction of equipment
shall be indicated by a clear visual or acoustic warning signal. Two types of
malfunctions are possible and are shown in Annex A together with their most
common causes.
Visual warning signals shall work with a pulse frequency between 2 Hz
and 0,2 Hz, emitting yellow or yellow-orange light. Visible warning signals
shall be installed inside or nearby the working area of welders in order to be
recognized when the light is on.
NOTE EN 842 provides additional guidance for visual danger signals. This
standard might also be part of national legislation.
If an acoustic warning device is installed, it shall work within an audio-
frequency between 500 Hz and 3 000 Hz and have a pulse time between
0,5 s and 5 s. The A-weighted sound pressure level shall be between 8 dB and
20 dB higher than the 1 m-surface sound pressure level of the welding fume
separation equipment.
Signals/indicators for normal operation
— For LEV:
Proper operation of a LEV shall be indicated by a control lamp emitting green light.
— For dampers on devices for capturing:
Capture equipment fitted with a manual shut off damper, the handle shall be
aligned with the damper position. For automatic dampers, the position shall
be indicated clearly visible to the user as open or closed.
Warning signals for malfunction Conformity shall be checked by simulating a malfunction
in order to test the function of the warning signal.
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[Table title] (continued)
Requirement Verification
— Separation equipment shall be fitted with a device that indicates that
the filter needs service (manual or automatic cleaning or replacement). When
any malfunction exists, the control lamp shall not emit green light and the
warning signals shall be active.
1.2 Carcinogenic substances require checking of airflow rate in the extraction Conformity shall be checked by simulating a malfunction
duct at each individual work place. in order to test the function of the warning signal.
Additional requirements for
equipment used for separation NOTE The airflow rate is measured indirectly, usually by measuring the
of carcinogenic substances duct pressure.
Warning signal for malfunction
— if the airflow rate in the extraction duct is insufficient, it shall be
indicated by a clear visual or acoustic warning signal.
1.3 Non-metallic parts (especially hoods, hoses and ducting properties) shall be Verification shall be performed by examining compliance
made of materials of low flammability. with the following:
Flammability
a) For hoods and hoses: GWEPT: 550 according to
IEC 60695-2-12 (glow-wire test temperature of 550 °C)
For ducting properties: GWEPT: 960 according to
IEC 60695-2- 12 (glow-wire test temperature of 960 °C)
NOTE The use of materials of higher flammability can
result in damage to the hose leading to reduced airflow at
the extraction point and hence poor extraction efficiency.
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5.2 Extraction devices
The requirements and corresponding verifications are given in Table 1.
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Table 1 — Requirements and verifications for extraction devices
Requirement Verification
1 Extraction Devices to be used close to the welding fume source (distance up to 0,4 m)
1.1 — The extraction device integrated to the torch shall be able to induce a sufficient Verification shall be performed by measuring the air
velocity, see Table below. These induced velocities shall be obtained with a limited flow rate and depression according to ISO 21904-4.
On-torch extraction
depression at the connector.
devices
Current [A] v [m/s] Needed depression at connector ∆p [kPa]
induced c
≤ 200 ≥ 0,25
≤ 18
> 200 ≥ 0,35
— The manufacturer of the torch shall use the results of the test according to EN
ISO 21904-4 to specify the air flow rate and the depression at the connector to achieve
the required induced velocity.
— In order to guarantee the efficiency on field, the design of the torch should not
allow operation if parts ensuring the capture are not assembled e.g. the nozzle (this
provision wants to prevent the dismantling of parts which the welder does not deem
necessary).
1.2 Captor hoods The extension of the suction field shall be determined in a measurement plane according Verification shall be performed by measuring the suction
and nozzles ISO 21904-4. field according to ISO 21904-4.
extraction devices
The suction field has to have an extension of at least 1,5 times the diameter of the attached Unsufficient performance of the hood can be compensated
duct in one direction and at least one duct diameter in the orthogonal direction. by increasing the volume flow rate. The size of the suction
field shall be verfied by performing a new measurement
with the new flow rate.
The necessary flow rate has to be assured by the manufacturer.
The manufacturer of a hood or nozzle shall use the results of the tests according to EN
ISO 21904-4 to specify and mark the device with the minimum air volume flow rate
required to achieve an air velocity of 0,3 m/s in the measurement plane, the distance of
the measurement plane from the entry plane and the position of the measurement points
selected to demonstrate the extent of the capture zone of the device. The measurement
points shall be identified by their (x, y)-co-ordinates projected from the entry plane.
NOTE A hood or nozzle is expected to achieve effective capture of welding fume if it is
operated with an air volume flow rate greater than or equal to the determined minimum
air volume flow rate and, in addition, if it is positioned at a distance less than or equal
to the distance between the measurement plane and the entry plane of the device.
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Table 1 (continued)
Requirement Verification
1.2.1 Extraction It shall be possible (see Figure 2) to move a flexible arm in any direction using a force Verification that the arm is easily movable shall be
devices with not exceeding 60 N at the handhold of the hood: achieved by measurement of forces and that it retains
flexible arms its position by visual inspection.
a) with the arm at 70 % of its maximum range;
b) at a point c, 1 300 mm ± 100 mm above ground level;
c) in the directions shown in Figure 1, over a range that is 10 % of the maximum
range. The movement in the Z-direction may follow an arc with radius a.
NOTE 1 If flexible arms do not fulfil the requirements, risk of incorrect use or non-use
will increase because of ergonomic reasons.
NOTE 2 The handhold is the point on the hood intended to be touched for movement.
The arm shall retain their position over the entire operating range after the force has
been removed.
1.2.2 Extraction No specific requirements
devices with fixed
arms
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Table 1 (continued)
Requirement Verification
Key
a
a
a 70 % of the maximum range
b
b Starting point of movement
c Point of force measurement
Figure 2 — Example for a moving force test setup
2 Extraction Devices to be used in the vicinity of the fume source (distance up to 1,5 m)
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Table 1 (continued)
Requirement Verification
Key
3 3
1 extraction hood, 2000 m /h to 4000 m /h, 100 Pa to 400 Pa
Figure 3
2.1 An air volume flow rate sufficient to remove all the fumes received shall be employed. Verification that no fume escapes
...
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