oSIST prEN ISO 15012-3:2016

Health and safety in welding and allied processes - Requirements, testing and marking of equipment for air filtration - Part 3: Determination of the capture efficiency of on-torch welding fume extraction devices (ISO/DIS 15012-3:2016)

This part of ISO 15012 defines a laboratory method for measuring the welding fume capture efficiency of ongun extraction systems. It is applicable to integrated on-gun systems and to systems where a discrete extraction system is attached to the welding torch close to the arc area. The methodology is suitable for use with all continuous wire welding processes, all material types and all welding parameters.
The method can be used to evaluate the effects of variables such as extraction flow rate, extract nozzle position, shielding gas flow rate, welding geometry, welding torch angle, fume emission rate etc. on capture efficiency but can also be used, with specific test conditions, to determine capture efficiency.

Arbeits- und Gesundheitsschutz beim Schweißen und bei verwandten Verfahren - Anforderungen, Prüfung und Kennzeichnung von Luftreinigungssystemen - Teil 3: Bestimmung des Erfassungsgrades von brennerintegrierten Absaugeinrichtungen für Schweißrauch (ISO/DIS 15012-3:2016)

Dieser Teil von ISO 15012 legt ein Laborverfahren zur Bestimmung des Erfassungsgrades von brennerinte-grierten Absaugeinrichtungen für Schweißrauch fest. Er ist anwendbar auf brennerintegrierte Systeme und Systeme, bei denen eine eigenständige Absauganlage am Schweißbrenner nahe des Lichtbogen-Bereiches angebracht ist. Das Verfahren eignet sich für den Einsatz bei allen kontinuierlichen Drahtschweißverfahren, allen Materialtypen und allen Schweißparametern.
Das Verfahren kann angewendet werden, um die Auswirkungen von Variablen wie Extraktionsdurchflussrate, Brennerposition, Schutzgasdurchfluss, Schweißgeometrie, Schweißbrennerwinkel, Abluftemissionsrate usw. auf Erfassungsgrades zu bestimmen.

Hygiène et sécurité en soudage et techniques connexes - Exigences, essais et marquage des équipements de filtration d'air - Partie 3: Détermination de l'efficacité de captage des systèmes d'extraction des fumées de soudage par torche aspirante (ISO/DIS 15012-3:2016)

Varnost in zdravje pri varjenju in sorodnih postopkih - Zahteve, preskušanje in označevanje opreme za filtriranje zraka - 3. del: Ugotavljanje učinkovitosti zajema pri napravah za ekstrakcijo (odsesavanje) varilnega dima (ISO/DIS 15012-3:2016)

General Information

• Status: Not Published
• Public Enquiry End Date: 24-Oct-2016
• ICS: 13.040.40 - Stationary source emissions
• ICS: 13.100 - Occupational safety. Industrial hygiene
• ICS: 25.160.10 - Welding processes
• Technical Committee: VAR - Welding
• Current Stage: 98 - Abandoned project (Adopted Project)
• Start Date: 11-Apr-2017
• Due Date: 16-Apr-2017
• Completion Date: 11-Apr-2017
• Ref Project: prEN ISO 15012-3 - Health and safety in welding and allied processes - Requirements, testing and marking of equipment for air filtration - Part 3: Determination of the capture efficiency of on-torch welding fume extraction devices (ISO/DIS 15012-3:2016)

Relations

• Revised: SIST EN ISO 21904-3:2018 - Health and safety in welding and allied processes - Requirements, testing and marking of equipment for air filtration - Part 3: Determination of the capture efficiency of on-torch welding fume extraction devices (ISO 21904-3:2018)
• Effective Date: 01-Oct-2018

Standards Content (Sample)

SLOVENSKI STANDARD
oSIST prEN ISO 15012-3:2016
01-oktober-2016
9DUQRVWLQ]GUDYMHSULYDUMHQMXLQVRURGQLKSRVWRSNLK=DKWHYHSUHVNXãDQMHLQ
R]QDþHYDQMHRSUHPH]DILOWULUDQMHGHO8JRWDYOMDQMHXþLQNRYLWRVWL]DMHPDSUL
QDSUDYDK]DHNVWUDNFLMRRGVHVDYDQMHYDULOQHJDGLPD,62',6
Health and safety in welding and allied processes - Requirements, testing and marking of
equipment for air filtration - Part 3: Determination of the capture efficiency of on-torch
welding fume extraction devices (ISO/DIS 15012-3:2016)
Arbeits- und Gesundheitsschutz beim Schweißen und bei verwandten Verfahren -
Anforderungen, Prüfung und Kennzeichnung von Luftreinigungssystemen - Teil 3:
Bestimmung des Erfassungsgrades von brennerintegrierten Absaugeinrichtungen für
Schweißrauch (ISO/DIS 15012-3:2016)
Hygiène et sécurité en soudage et techniques connexes - Exigences, essais et
marquage des équipements de filtration d'air - Partie 3: Détermination de l'efficacité de
captage des systèmes d'extraction des fumées de soudage par torche aspirante
(ISO/DIS 15012-3:2016)
Ta slovenski standard je istoveten z: prEN ISO 15012-3
ICS:
13.040.40 (PLVLMHQHSUHPLþQLKYLURY Stationary source emissions
13.100 Varnost pri delu. Industrijska Occupational safety.
higiena Industrial hygiene
25.160.10 Varilni postopki in varjenje Welding processes
oSIST prEN ISO 15012-3:2016 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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oSIST prEN ISO 15012-3:2016
DRAFT INTERNATIONAL STANDARD
ISO/DIS 15012-3
ISO/TC 44/SC 9 Secretariat: BSI
Voting begins on: Voting terminates on:
2016-08-02  2016-10-24
Health and safety in welding and allied processes —
Requirements, testing and marking of equipment for air
filtration —
Part 3:
Determination of the capture efficiency of on-gun welding
fume extraction devices
Hygiène et sécurité en soudage et techniques connexes — Exigences, essais et marquage des équipements
de filtration d’’air —
Partie 3: Détermination de l’efficacité de la prise des appareils d’extraction des fumées de soudage
ICS: 25.160.30
THIS DOCUMENT IS A DRAFT CIRCULATED
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 15012-3:2016(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 2016

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ISO/DIS 15012-3:2016(E)

COPYRIGHT PROTECTED DOCUMENT
© ISO 2016, Published in Switzerland
All rights reserved. Unless otherwise specified, 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
Ch. de Blandonnet 8 • CP 401
CH-1214 Vernier, Geneva, Switzerland
Tel. [phone]
Fax [phone]
[e-mail]
www.iso.org
ii © ISO 2016 – All rights reserved

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Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3  Terms and definitions . 1
4 Principle . 2
5 Test equipment and materials . 2
5.1 General requirement . 2
5.2 Test chamber . 2
5.3 Isokinetic samplers . 2
5.4 Total fume and isokinetic filters. 2
5.5 Extraction fan . 2
5.6 On-torch extraction unit . 3
5.7 Equipment for measuring welding current, welding voltage, wire feed speed and
arcing time . 3
5.8 Equipment for direct-reading of fume concentration . 3
5.9 Equipment for measuring the mass of fume collected . 3
5.10 Equipment for measuring shielding gas volume flow rate . 3
5.11 Device for automatic welding . 3
5.12 Device for measuring contact tip to workpiece distance (CTWD) . 3
5.13 Device for measuring static pressure . 4
5.14 Device for measuring the mass flow rate . 4
5.15 Materials . 4
6 Test procedure . 4
6.1 Preliminary tests . 4
6.1.1 Setting the shielding gas flow rate . 4
6.1.2 Measuring the flow rates and determination of leakage . 4
6.2 Setting up the test equipment . 5
6.3 Capture efficiency tests . 6
6.3.1 General. 6
6.3.2 Test procedure . 6
6.3.3 Calculation of the results . 7
7  Test parameters for generating comparable test report capture efficiency data .8
8  Test report . 9
Annex A (informative) Examples of test chambers .10
Annex B (informative) Equipment notes .12
Annex C (informative) Trial tests .14
Annex D (normative) Test procedures.16
Annex E (informative) Data processing for test method 3 .17
Annex F (normative) Test parameters form to be filled .19
Annex G (informative) Suggested parameters for testing .20
Annex H (informative) Information about the necessity to measure leakage .21
Bibliography .22
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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 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.
The committee responsible for this document is ISO/44/SC 9.
A list of all parts in the ISO 15012- series can be found on the ISO website.
iv © ISO 2016 – All rights reserved

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Introduction
Welding generates fumes and gases which, if inhaled, can be harmful to human health. Therefore,
control of the fume and gases must be exercised to minimise worker exposure.
The most effective method of welding fume control is local exhaust ventilation (LEV) which captures
the fumes at source before they enter the general environment and the breathing zone of workers.
One form of LEV used in welding is on-torch extraction in which the extraction system is either an
integral part of the welding torch or is attached to it close to the arc area. Anecdotal evidence within
the fabrication industry suggested that it is impossible to capture fume efficiently whilst maintaining
[[4]]
weld metal integrity but research (see bibliography ) has shown this not to be the case, certainly as
far as weld metal porosity is concerned.
This part of EN 15012 prescribes a method for measuring the capture efficiency of on-torch extraction
systems. The procedure only prescribes a methodology, leaving selection of the test parameters to the
user, so that the effect of different variables may be evaluated.
It has been presumed in the drafting of this standard that the executions of its provisions and the
interpretation of the results obtained are entrusted to appropriately qualified and experienced people.
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oSIST prEN ISO 15012-3:2016
DRAFT INTERNATIONAL STANDARD  ISO/DIS 15012-3:2016(E)
Health and safety in welding and allied processes —
Requirements, testing and marking of equipment for air
filtration —
Part 3:
Determination of the capture efficiency of on-gun welding
fume extraction devices
1 Scope
This part of ISO 15012 defines a laboratory method for measuring the welding fume capture efficiency
of on-torch extraction systems. It is applicable to integrated on-torch systems and to systems where
a discrete extraction system is attached to the welding torch close to the arc area. The methodology
is suitable for use with all continuous wire welding processes, all material types and all welding
parameters.
The method can be used to evaluate the effects of variables such as extraction flow rate, extract nozzle
position, shielding gas flow rate, welding geometry, welding torch angle, fume emission rate etc. on
capture efficiency.
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 15767, Workplace atmospheres — Controlling and characterizing uncertainty in weighing collected
aerosols
ISO/IEC Guide 98, Uncertainty of measurement — All parts
3  Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
test chamber
semi-enclosed extracted chamber in which welding fume capture efficiency testing is performed
3.2
isokinetic sampler
device for collecting aerosol samples at the same velocity as the air being sampled
3.3
test chamber sampling duct
duct between the test chamber and an extraction fan in which all the fume generated can be collected
or sampled isokinetically
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3.4
emission rate
mass of the particles emitted by the welding fume source per unit time
Note 1 to entry: Emission rate is expressed in mg/s.
4 Principle
Automatic welding is performed using the on-torch extraction torch under test, on a test piece, inside
a continuously extracted test chamber. Testing is carried out using identical welding parameters with
and without the on-torch extraction activated. The ratio of measurements in the test chamber sampling
duct is used to calculate the capture efficiency of the on-torch extraction torch.
Three methods of measuring the fume can be used. Two methods employ gravimetric measurement.
The first method measures the total fume generated whilst second method employs isokinetic sampling
in the test chamber sampling duct. The third method employs a direct reading measuring technique in
the test chamber sampling duct.
5 Test equipment and materials
5.1  General requirement
The test setup shall enable containment of the fume generated in the arc area within the test chamber
whilst ensuring the air velocity in the welding area below the torch does not exceed 0,2 m/s without
welding and with the on-torch extraction off. See also B.1.
NOTE It is possible that not all of the fume generated by spatter production will be contained within the test
chamber.
5.2  Test chamber
A continuously extracted chamber of sufficient dimensions to enclose the welding operation. Either the
chamber shall be constructed of materials that will withstand close proximity to the heat and spatter
generated by the welding or the chamber shall be designed so that the materials used are sufficiently
distant from the arc to avoid problems arising from heat and spatter generation. See Figures A.1 and A.2.
Compliance with the requirements of clause 5.1 shall be verified.
5.3  Isokinetic samplers
The sample flow rate shall be such that the velocity through the sample inlet is the same as the
surrounding air velocity. This ensures that the particle size distribution is unaffected by the sampling
process and therefore the sample represents the particles present in the sampling duct. See also C.3.
5.4  Total fume and isokinetic filters
Filters, manufactured from glass or quartz fibre, with particle retention properties down to
approximately 1 µm to 2 µm. The filters shall not tear or perforate during testing (see B.3) and shall not
be so friable that fibres can be lost from the filters during handling.
Filters shall be treated according to the procedures defined in ISO 15767.
5.5  Extraction fan
The extraction fan for the sampling chamber shall be capable of maintaining a constant flow rate
(± 2 %) in the test chamber sampling duct during testing when using during testing with iso-kinetic
sampling or direct reading equipment.
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The air flow generated by the fan shall be capable of retaining the entire fume generated within the test
chamber.
5.6  On-torch extraction unit
The on-torch extraction unit shall be capable of maintaining a constant flow rate (± 2 %) in the on-torch
extraction line during testing.
5.7  Equipment for measuring welding current, welding voltage, wire feed speed and
arcing time
Equipment capable of measuring the current, voltage, wire feed speed and the arcing time within
± 1% . Electronic integrating equipment with frequent sampling intervals and a logging capability is
recommended. See also Annex D.
In the absence of such equipment, current may be measured using a shunt or a Hall Effect probe
connected to a moving coil meter. Voltage may be measured using a moving coil meter. Wire feed speed
may be determined by measuring the length of wire exiting the welding torch in a measured time. The
calibration of the equipment shall be traceable to national standards.
5.8  Equipment for direct-reading of fume concentration
The equipment shall have a reading that is directly proportional to the concentration with a maximum
linearity error of 5% over the expected concentration range.
NOTE Equipment suitable for direct-reading of fume concentration is described for example in
CEN/TR 16013.
5.9  Equipment for measuring the mass of fume collected
A balance, capable of measuring the mass of isokinetic sample filters and isokinetic sample filters plus
fume with an accuracy of ± 0,01 mg or better.
A balance, capable of measuring the mass of total fume collection filters and total fume collection filters
plus fume with an accuracy of ± 1 mg or better.
The balance calibrations shall be traceable to national standards.
5.10 Equipment for measuring shielding gas volume flow rate
Equipment calibrated for the shielding gas in use, capable of measuring the volume flow rate to within
± 5% or better. See B.4.
The calibration of the equipment shall be traceable to national standards.
5.11 Device for automatic welding
A device that permits the capture efficiency test to be performed under automated conditions, capable
of advancing the test piece under a stationary welding torch at an appropriate rate (welding speed). It
shall be possible to secure the test piece to the device, such that it cannot bow during welding.
5.12 Device for measuring contact tip to workpiece distance (CTWD)
A gauge, made by machining a metal block to a thickness equivalent to the required CTWD to within
± 5% or better, or a metal wedge with distance markings at appropriate points.
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5.13 Device for measuring static pressure
A device capable of measuring static air pressure in the on-torch extraction line with an uncertainty of
measurement not exceeding ± 1% of the reading, traceable to national standards. See B.8.
5.14 Device for measuring the mass flow rate
A device for measuring the mass flow rate to an accuracy of ± 5 % or better, traceable to national
standards (e.g. according to EN ISO 5167). See B.9.
5.15 Materials
The same batch of filler wire and test pieces shall be used for each test series.
Test pieces, of a material and dimensions that are suitable for the capture efficiency test to be carried
out, that allow a weld of sufficient length to be continuously deposited. See B.6.
6 Test procedure
6.1  Preliminary tests
6.1.1  Setting the shielding gas flow rate
Set the shielding gas flow rate using the equipment described in 5.10.
6.1.2  Measuring the flow rates and determination of leakage
Measure the mass flow rate at two points shown in Figure 1, without welding, by using appropriate
devices and calculate the air volume flow rate. See also B.7 and Annex H.
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Key
1 device to permit mass flow rate measurement at extraction inlet on the connector of the torch
2
measurement point of the mass flow rate at the connector Q
mconnector
3 connection between the torch and the extraction system
4 on-torch extraction torch
5 device to permit mass flow rate measurement at extraction inlet on the torch (see B.9)
6
measurement point of the mass flow rate at the nozzle Q
m nozzle
7 sealing
8 airflow
Figure 1 — - Points for measuring the flow rate
QQ−
mconnector m nozzle
The leakage ratio is
Q
mconnector
From mass flow rates ( Q and Q ), the volume flow rates (Q and Q ) are
m nozzle mconnector v nozzle vconnector
calculated with the theoretical conditions of temperature and pressure of 20 °C and 101 325 Pa
(1 013,25 hPa):
Q
m
Q =
v
ρ
3
where ρ is the air density at 20 °C = 1,204 kg/m .
6.2  Setting up the test equipment
Set up the test equipment as shown in Figure 2, in an interference-free environment (see B.10).
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Key
1 Method 1 (total mass measurement), according to Table 1
2 Method 2 (isokinetic sampling with a weighed filter), according to Table 1
3 Method 3 (direct reading in the duct or after isokinetic sampling), according to Table 1
4 flowrate measurement
5 static pressure measurement
6 total fume filter
7 welding unit
8 sample filter
9 direct reading instrument
Figure 2 — - Setup for the different measurement methods
6.3  Capture efficiency tests
6.3.1  General
Before starting the capture efficiency test, make sure that all welding conditions and flow rates are set
to the desired values by performing trial tests. Guidance on performing trial tests is given in Annex C.
6.3.2  Test procedure
The steps for carrying out the three different test methods are given in Table 1. For the setup for the
different measurement methods see Figure 2.
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Table 1 — Test procedure
Step num-
Method 1 Method 2 Method 3
ber
1 Switch on the on-torch extraction unit.
Measure and record the static pressure at the entry to the extraction system on the welding
2
torch. See B.9.
Measure and record the air flow rate at the entry to the extraction system on the welding torch.
3
See B.9.
Install a pre-weighed filter in the appropriate position, see Position the probe in the appro-
4
Figure 2. priate position, see Figure 2.
Renew or reposition the test piece so that the next weld will be on unused material.
Check that the CTWD is correct, see Annex D.
5
Position the test piece under the torch ready to commence welding. Switch on the extraction fan
to the test chamber (5.2). Check and adjust the flow rate if necessary.
Switch on the pump for the
Start to record the concentra-
6 isokinetic sampler. Check and
tion signal.
adjust the flow rate if necessary.
Start the device for automatic welding. Wait for the initial pulse of shielding gas to disappear and
a stable shielding gas flow rate is obtained.
Commence welding and begin timing.
7
Stop welding after the required arcing time (see 6.3.3) and record the time.
Leave the extraction fan on until the fume generated has been cleared from the test chamber (at
least 60 s)
Switch off the pump to the Stop recording the concentra-
8
isokinetic sampler. tion signal.
9 Switch off the on-torch extraction unit and the extraction fan.
10 Remove the filter and reweigh it after appropriate conditioning
11 Repeat steps 4 to 10, i.e. with the on-torch extraction off.
Repeat steps 1 to 11 four times, i.e. five tests with the on-torch extraction on and five tests with
12
the on-torch extraction off.
6.3.3  Calculation of the results
The steps for carrying out the three different test methods are given in Table 2.
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Table 2 — Calculation of test results
Step
num- Method 1 Method 2 Method 3
ber
Calculate X according to numerical equation 1: Calculate X according to numerical
i i
equation 2:
m
i
   X = (1)
i τ +60s
1,i
τ
i ct()dt
∫
τ
0,i
Where
   X = (2)
i
τ
i
m is the mass collected on the filter,
1 Where
τ is the arcing time, and
c is the concentration,
i is the test number.
τ is the arcing time, and
i is the test number.
Note: For further information see Annex E.
If any individual result within the series with the on-torch extraction off differs from the respective
mean by more than ± 15 %, carry out checks to ensure that all equipment is functioning correctly and
repeat the entire procedure.
||XX−
i
   < 01, 5 (3)
2
X
where
5
1
   XX= Σ() (4)
i
i=1
5
Calculate the capture efficiency according to formula 5.
X on
η =−1 (5)
X
off
Where
3
X = average X with the on-torch extraction on.
on
i
-torch extraction off.
X off = average X with the on
i
Estimate the uncertainty of the measurements in accordance with the ISO Guide 98.
7  Test parameters for generating comparable test report capture efficiency data
The tests shall be carried out with the parameters given in Table 3. The values given in Table 3 are
based on typical we
...