SIST EN ISO 20568-2:2017
(Main)Plastics - Fluoropolymer dispersions and moulding and extrusion materials - Part 2: Preparation of test specimens and determination of properties (ISO 20568-2:2017)
Plastics - Fluoropolymer dispersions and moulding and extrusion materials - Part 2: Preparation of test specimens and determination of properties (ISO 20568-2:2017)
This document describes the preparation of test specimens and provides test methods to define
characteristics of thermoplastic fluoropolymer resins. Results from the testing can be used as the basis
for designation, material specifications or both.
Kunststoffe - Fluorpolymerdispersionen, Formmassen und Extrusionsmaterialien - Teil 2: Herstellung von Probekörpern und Bestimmung von Eigenschaften (ISO 20568-2:2017)
Dieses Dokument beschreibt die Herstellung von Probekörpern und bietet Prüfverfahren zum Festlegen von Merkmalen von thermoplastischen Fluorpolymerharzen. Die Prüfergebnisse können als Grundlage für die Bezeichnung und Materialspezifikationen oder für beides dienen.
Plastiques - Polymères fluorés: dispersions et matériaux pour moulage et extrusion - Partie 2 : Préparation des éprouvettes et détermination des propriétés (ISO 20568-2:2017)
ISO 20568-2:2017 décrit la préparation des éprouvettes et indique les méthodes d'essai à utiliser pour définir les caractéristiques des résines thermoplastiques de polymères fluorés. Les résultats d'essai peuvent être utilisés comme base pour la désignation et/ou la spécification de la matière.
Polimerni materiali - Disperzije in materiali za oblikovanje in ekstrudiranje na osnovi fluoropolimerov - 2. del: Priprava preskušancev in določanje lastnosti (ISO 20568-2:2017)
Ta dokument opisuje pripravo preskušancev in določa preskusne metode za določanje
lastnosti plastomernih fluoropolimernih smol. Rezultati preskušanja se lahko uporabijo kot podlaga za označevanje, specifikacije materialov ali oboje.
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
SIST EN ISO 20568-2:2017
01-september-2017
1DGRPHãþD
SIST EN ISO 12086-2:2006
SIST EN ISO 12086-2:2006/AC:2009
3ROLPHUQLPDWHULDOL'LVSHU]LMHLQPDWHULDOL]DREOLNRYDQMHLQHNVWUXGLUDQMHQD
RVQRYLIOXRURSROLPHURYGHO 3ULSUDYDSUHVNXãDQFHYLQGRORþDQMHODVWQRVWL ,62
Plastics - Fluoropolymer dispersions and moulding and extrusion materials - Part 2:
Preparation of test specimens and determination of properties (ISO 20568-2:2017)
Kunststoffe - Fluorpolymerdispersionen, Formmassen und Extrusionsmaterialien - Teil 2:
Herstellung von Probekörpern und Bestimmung von Eigenschaften (ISO 20568-2:2017)
Plastiques - Polymères fluorés: dispersions et matériaux pour moulage et extrusion -
Partie 2 : Préparation des éprouvettes et détermination des propriétés (ISO 20568-
2:2017)
Ta slovenski standard je istoveten z: EN ISO 20568-2:2017
ICS:
83.080.20 Plastomeri Thermoplastic materials
SIST EN ISO 20568-2:2017 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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SIST EN ISO 20568-2:2017
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SIST EN ISO 20568-2:2017
EN ISO 20568-2
EUROPEAN STANDARD
NORME EUROPÉENNE
June 2017
EUROPÄISCHE NORM
ICS 83.080.20 Supersedes EN ISO 12086-2:2006
English Version
Plastics - Fluoropolymer dispersions and moulding and
extrusion materials - Part 2: Preparation of test specimens
and determination of properties (ISO 20568-2:2017)
Plastiques - Polymères fluorés: dispersions et Kunststoffe - Fluorpolymerdispersionen, Formmassen
matériaux pour moulage et extrusion - Partie 2: und Extrusionsmaterialien - Teil 2: Herstellung von
Préparation des éprouvettes et détermination des Probekörpern und Bestimmung von Eigenschaften
propriétés (ISO 20568-2:2017) (ISO 20568-2:2017)
This European Standard was approved by CEN on 29 April 2017.
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, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,
Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, 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: Avenue Marnix 17, B-1000 Brussels
© 2017 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 20568-2:2017 E
worldwide for CEN national Members.
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SIST EN ISO 20568-2:2017
EN ISO 20568-2:2017 (E)
Contents Page
European foreword . 3
2
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SIST EN ISO 20568-2:2017
EN ISO 20568-2:2017 (E)
European foreword
This document (EN ISO 20568-2:2017) has been prepared by Technical Committee ISO/TC 61 "Plastics"
in collaboration with Technical Committee CEN/TC 249 “Plastics” the secretariat of which is held by
NBN.
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 December 2017 and conflicting national standards
shall be withdrawn at the latest by December 2017.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent
rights.
This document supersedes EN ISO 12086-2:2006.
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, Former Yugoslav Republic of Macedonia,
France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta,
Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey and the United Kingdom.
Endorsement notice
The text of ISO 20568-2:2017 has been approved by CEN as EN ISO 20568-2:2017 without any
modification.
3
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SIST EN ISO 20568-2:2017
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SIST EN ISO 20568-2:2017
INTERNATIONAL ISO
STANDARD 20568-2
First edition
2017-05
Plastics — Fluoropolymer dispersions
and moulding and extrusion
materials —
Part 2:
Preparation of test specimens and
determination of properties
Plastiques — Polymères fluorés: dispersions et matériaux pour
moulage et extrusion —
Partie 2: Préparation des éprouvettes et détermination des propriétés
Reference number
ISO 20568-2:2017(E)
©
ISO 2017
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SIST EN ISO 20568-2:2017
ISO 20568-2:2017(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2017, 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
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Tel. +41 22 749 01 11
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copyright@iso.org
www.iso.org
ii © ISO 2017 – All rights reserved
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SIST EN ISO 20568-2:2017
ISO 20568-2:2017(E)
Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 2
4 Preparation of test specimens . 2
5 Conditioning and test conditions . 2
6 Determination of properties . 2
7 Testing of PTFE . 2
7.1 Testing of polytetrafluoroethylene (PTFE) granular moulding and ram extrusion
materials, and for PTFE resin produced from coagulation of dispersion . 2
7.1.1 Standard specific gravity (SSG) . 2
7.1.2 Bulk density . 4
7.1.3 Particle size and size distribution . 8
7.2 Testing of polytetrafluoroethylene (PTFE) dispersion .15
7.2.1 Preparation of test samples .15
7.2.2 Percentage PTFE and surfactant in aqueous dispersion .15
8 Testing of melt processable fluoropolymers .16
8.1 Testing of CPT, ECTFE, EFEP, ETFE, FEP, PFA, PVDF, PVF, VDF/CTFE, VDF/HFP,
VDF/TFE, VDF/TFE/HFP .16
8.1.1 Melting-peak temperature .16
8.1.2 Melt mass-flow rate (MFR) .16
8.2 Testing of PCTFE .18
8.2.1 Zero-strength time .18
8.3 Testing of TFE/PDD .18
8.3.1 Glass transition temperature .18
8.4 Testing of melt processable fluoropolymers dispersion .19
Bibliography .20
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SIST EN ISO 20568-2:2017
ISO 20568-2:2017(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www .iso .org/ directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see http:// 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: w w w . i s o .org/ iso/ foreword .html.
This document was prepared by Technical Committee ISO/TC 61, Plastics, Subcommittee SC 9,
Thermoplastic materials.
This first edition of ISO 20568-2 cancels and replaces ISO 12086-2:2006, which has been technically
revised.
A list of all parts in the ISO 20568 series can be found on the ISO website.
iv © ISO 2017 – All rights reserved
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SIST EN ISO 20568-2:2017
INTERNATIONAL STANDARD ISO 20568-2:2017(E)
Plastics — Fluoropolymer dispersions and moulding and
extrusion materials —
Part 2:
Preparation of test specimens and determination of
properties
SAFETY STATEMENT — Persons using this document should be familiar with normal laboratory
practice, if applicable. This document does not purport to address all of the safety concerns, if
any, associated with its use. It is the responsibility of the user to establish appropriate safety
and health practices and to ensure compliance with any regulatory requirements. The warnings
in 7.1.1.4 and 7.1.3.1 point out specific hazards.
1 Scope
This document describes the preparation of test specimens and provides test methods to define
characteristics of thermoplastic fluoropolymer resins. Results from the testing can be used as the basis
for designation, material specifications or both.
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 291, Plastics — Standard atmospheres for conditioning and testing
ISO 472, Plastics — Vocabulary
ISO 565, Test sieves — Metal wire cloth, perforated metal plate and electroformed sheet — Nominal sizes
of openings.
ISO 1133-1:2011, Plastics — Determination of the melt mass-flow rate (MFR) and melt volume-flow rate
(MVR) of thermoplastics — Part 1: Standard method
ISO 11357-2, Plastics — Differential scanning calorimetry (DSC) — Part 2: Determination of glass transition
temperature and glass transition step height
ISO 11357-3, Plastics — Differential scanning calorimetry (DSC) — Part 3: Determination of temperature
and enthalpy of melting and crystallization
ASTM D1430, Standard Classification System for Polychlorotrifluoroethylene (PCTFE) Plastics
ASTM D4591, Standard Test Method for Determining Temperatures and Heats of Transitions of
Fluoropolymers by Differential Scanning Calorimetry
ASTM D4894, Standard Specification for Polytetrafluoroethylene (PTFE) Granular Molding and Ram
Extrusion Materials
ASTM D4895, Standard Specification for Polytetrafluoroethylene (PTFE) Resin Produced From Dispersion
ASTM E11, Standard Specification for Woven Wire Test Sieve Cloth and Test Sieves
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SIST EN ISO 20568-2:2017
ISO 20568-2:2017(E)
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 472 apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— IEC Electropedia: available at http:// www .electropedia .org/
— ISO Online browsing platform: available at http:// www .iso .org/ obp
4 Preparation of test specimens
Where applicable, ISO standards shall be followed for the preparation of test specimens. In some instances,
special procedures are required that are described either in the general discussion or in the method.
5 Conditioning and test conditions
For determinations of specific gravity, condition the moulded test specimens in atmosphere 23 of
ISO 291 for a period of at least 4 h prior to testing. The other determinations require no conditioning.
Conduct tests at a laboratory temperature of 23 °C ± 2 °C for determining specific gravity.
A minimum temperature of 22 °C should preferably be maintained with PTFE due to its first-order
transition just below 22 °C that affects properties determined at slightly lower temperatures. This
effect of temperature is especially important during the determination of density/specific gravity.
6 Determination of properties
Properties required for designation or specification, or both, shall be determined in accordance with
the international or national standards listed in Clause 2 or the procedures given in this document.
7 Testing of PTFE
7.1 Testing of polytetrafluoroethylene (PTFE) granular moulding and ram extrusion
materials, and for PTFE resin produced from coagulation of dispersion
7.1.1 Standard specific gravity (SSG)
7.1.1.1 Use the PTFE powder as received.
7.1.1.2 A cylindrical preforming mould is used to prepare the preforms prior to sintering. The mould
is a tube 28,6 mm in internal diameter by at least 76,2 mm deep, with a removable bottom insert
and a piston. Clearance between the piston and wall of the mould shall be sufficient to ensure escape
of entrapped air during compression. Place flat aluminium foil discs, normally 0,13 mm thick and
28,6 mm in diameter, on each side of the resin. The test resin shall be near ambient temperature prior
to preforming. For maximum precision, the weighing and performing operations shall be carried out
in a constant-temperature room at 23 °C ± 1 °C. The method shall not be run below 22 °C due to the
“room temperature” crystalline transition of PTFE which may lead to cracks in sintered specimens and
differences in specimen density. ASTM D4895 provides additional details.
7.1.1.3 Weigh out 12,0 g ± 0,1 g of resin and place it in the preforming mould. Screen non-free-flowing
resins through a 2,00 mm (No. 10) sieve. Compacted resins can be broken up by hand-shaking cold resin
in a half-filled sealed glass container. To do this, first condition the resin in the sealed glass container in a
freezer or dry-ice chest. After shaking to break up resin lumps, allow the sealed container to equilibrate
to near ambient temperature. Then screen and weigh the 12,0 g ± 0,1 g test sample. Insert the mould in
2 © ISO 2017 – All rights reserved
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SIST EN ISO 20568-2:2017
ISO 20568-2:2017(E)
a suitable hydraulic press and apply pressure gradually (see Note) until the desired pressure is attained.
The pressure shall be 34,5 MPa for PTFE granular moulding and ram extrusion materials, and 14 MPa for
PTFE resin produced from coagulation of dispersion. Hold the pressure on the preform for 2 min. Release
the pressure and remove the preform from the mould. A wax pencil may be used at this time to write an
identification marking on the preform.
NOTE As a guide, increasing the pressure at a rate of 3,5 MPa/min is suggested until the desired maximum
is attained.
7.1.1.4 Place the sintering oven in a laboratory hood (or equip it with an adequate exhaust system)
and sinter the preforms in accordance with the schedule in Table 1.
WARNING — PTFE resin can evolve small quantities of gaseous products when heated above
260 °C. Some of these gases are harmful. Consequently, exhaust ventilation must be used
whenever the resins are heated above this temperature.
Table 1 — Sintering conditions for preparing SSG specimens
Initial temperature 290
Rate of heating, °C/h 120 ± 10
Hold temperature, °C 380 ± 6
Hold time, min
+2
for SSG specimens
30
0
Cooling rate to 294 °C, °C/h 60 ± 5
Second hold temperature, °C 294 ± 6
+0,5
Second hold time, min
24
0
Time to room temperature, min > 30
Improved precision in the test values for standard specific gravity has been obtained with the use
of an upright cylindrical oven and an aluminium sintering rack. The cylindrical oven has an inside
diameter of 140 mm and a depth of 203 mm, plus additional depth to accommodate a 50,8 mm cover,
and is equipped with adequate band heaters and controls to accomplish the sintering of specimens in
accordance with Table 1. The rack, as shown in Figure 1, allows preforms to be placed symmetrically
in the centre region of the oven. Place six preforms on each of the middle oven rack shelves. (If six or
less preforms are to be sintered, place them on the middle rack, filling in with “dummy” specimens as
needed.) Place dummy specimens on the top and bottom shelves. Space the specimens evenly in a circle
on each shelf, with none of them touching. An oven load shall be no less than 18 pieces, including the
additional dummy pieces. (Dummies are defined as normal 12 g specimens that have previously been
through the sintering cycle. Dummies shall be used only for an additional two or three thermal cycles,
due to eventual loss of thermal stability and physical form.) Consult ASTM D4894 or ASTM D4895 for
additional details.
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SIST EN ISO 20568-2:2017
ISO 20568-2:2017(E)
Dimensions in millimetres
Key
1 support rods, diam. 6,35 mm (four required)
2 shelves, made of type 3003-H14 20 GA aluminium (five required)
NOTE Aluminium plates tack-welded to rods.
Figure 1 — Rack for sintering oven
7.1.2 Bulk density
Bulk density gives an indication of how a resin can perform during the filling of processing equipment.
PTFE resins tend to compact during shipment and storage and, even though the material may be broken
up by screening or some other means, original “as produced” results may not be duplicated. Because of
this tendency to pack under small amounts of compression or shear, the procedure given in 7.1.2.2 shall
be used to measure this property. This procedure can also be found in ASTM D4894 and ASTM D4895.
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SIST EN ISO 20568-2:2017
ISO 20568-2:2017(E)
7.1.2.1 Apparatus
7.1.2.1.1 Funnel, as shown in Figure 2.
7.1.2.1.2 Feeder, with a wire screen having 2,38 mm openings placed over approximately the top two-
1)
thirds of the trough. The funnel shall be mounted permanently in the feeder outlet .
2)
7.1.2.1.3 Controller .
7.1.2.1.4 Volumetric cup and cup stand, as shown in Figure 3. The top and bottom of both cup and
stand shall be flat and parallel to within 0,05 mm. The inside bottom corner of the cup shall be square, as
shown in the figure, and the bottom of the hole in the cup stand shall be square with the centreline and
with the top surface of the stand. All sharp external corners shall be removed from the cup stand.
The volumetric cup shall be calibrated initially to 250 ml by filling it with distilled water, placing a
planar glass plate on top, drying the outside of the cup, and weighing. The net mass shall be 250 g ± 0,5 g.
7.1.2.1.5 Levelling device, as shown in Figure 4, affixed permanently on the work table and adjusted
so that the sawtooth edge of the leveller blade passes within 0,8 mm of the top of the volumetric cup.
7.1.2.1.6 Work surface, for holding the volumetric cup and leveller. It shall be essentially free from
vibration. The feeder, therefore, shall be mounted on an adjoining table or wall bracket.
7.1.2.1.7 Balance, having an extended beam, and with a capacity of 500 g and a sensitivity of 0,1 g or
equivalent.
7.1.2.2 Procedure
Place the clean, dry volumetric cup on the extended beam of the balance and adjust the tare to zero.
Select about 500 ml of the resin to be tested and place it on the feeder screen. Put the cup in the cup
stand and place the assembly such that the distance of free fall from the feeder outlet to the top rim of
the cup is 38,1 mm ± 3,2 mm. Increased fall causes packing in the cup and higher bulk-density values.
Set the controller so that the cup is filled in 20 s to 30 s. Pour the sample on to the vibrating screen and
fill the cup so that the resin forms a mound and overflows. Let the resin settle for about 15 s and then
gently push the cup and its stand beneath the leveller. Exercise care to avoid agitation of the resin and
cup before levelling. Weigh the resin to the nearest 0,1 g.
7.1.2.3 Expression of results
Calculate the bulk density, in grams per litre, as follows:
Mass of resin in cup × 4 = Bulk density
1) A laboratory-sized vibrating feeder has been found satisfactory for this purpose. Originally used was
a “Vibra-Flow” feeder, Type F-T01A, with trough, which may still be available. This information is given for the
convenience of users of this document and does not constitute an endorsement by ISO of this product. Equivalent
products may be used if they can be shown to lead to the same results.
2) A suitable controller for the feeder should be used. Originally used was a “Syntron” controller, Type CSCRBI,
which may still be available. This information is given for the convenience of users of this document and does not
constitute an endorsement by ISO of this product. Equivalent products may be used if they can be shown to lead to
the same results.
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SIST EN ISO 20568-2:2017
ISO 20568-2:2017(E)
Dimensions in millimetres
Key
1 weld
2 two support gussets, approx. 13 mm × 13 mm × 1,6 mm thick, located in positions shown
3 bend
4 straightening vanes (locate two partitions as shown)
a
Depth of partitions.
NOTE Funnel material: type 304 stainless steel, 16 gauge (1,6 mm thickness).
Figure 2 — Details of funnel used for determination of bulk density
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SIST EN ISO 20568-2:2017
ISO 20568-2:2017(E)
Dimensions in millimetres
a) Volumetric cup b) Cup stand
(Material: type 304 stainless seamless tubing) (Material: 17 S-T aluminium or equivalent)
a
Weld all round and grind smooth.
Figure 3 — Volumetric cup and cup stand for determination of bulk density
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SIST EN ISO 20568-2:2017
ISO 20568-2:2017(E)
Dimensions in millimetres
Key
1 cup stand
2 cup
3 210 mm × 53 mm × 6 mm type 304 stainless-steel plate (or strap-welded across top for rigidity)
4 leveller blade (e.g. Atkins saw blade No. 614-P), sawtooth edge, six teeth per 25 mm, 1,6 mm deep
5 use shimstock or washers to take up clearance in 2,4 mm wide gap between the angle and saw blade
6 6 mm diam. × 19 mm long brass rivet (two required) plus 2,4 mm diam. × 19 mm long brass cotter pin (two
required) for mounting saw blade firmly in position (drill hole through angle and blade to 0,12 mm clearance
with diameter of cotter pin)
7 25 mm × 25 mm × 3 mm type 304 stainless-steel angles (four required — two each end)
8 51 mm × 51 mm × 3 mm stainless-steel gussets (four required — two each end)
9 type 304 stainless-steel plate
a
Gap left between angles for mounting saw blade.
Figure 4 — Leveller stand for determination of bulk density
7.1.3 Particle size and size distribution
The wet and dry-sieve procedures of 7.1.3.1 and 7.1.3.2 are widely used with PTFE. The resistance-
variation test procedure in 7.1.3.3 (the Coulter principle) is often used with PTFE fine-cut suspension
powders. The light-scattering procedures in 7.1.3.4 are becoming more widely used. The use of
automatic or other instruments that have been shown to provide equivalent results is an acceptable
alternative.
7.1.3.1 Wet-sieve analysis
WARNING — Perchloroethylene is under investigation by government agencies and industry for
its carcinogenic effects. Establish protective measures in accordance with applicable health and
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SIST EN ISO 20568-2:2017
ISO 20568-2:2017(E)
safety requirements to prevent skin contact and provide ventilation of vapours. The supplier’s
SDS sheet should be consulted for more information about required safety measures.
7.1.3.1.1 Apparatus and materials
7.1.3.1.1.1 Balance, capable of weighing to ± 0,1 g.
7.1.3.1.1.2 Standard sieves, 203 mm diameter, conforming to ISO 565. It is suggested that the
following sieve openings (sieve numbers) be used: 1,4 mm (No. 14), 1 mm (No. 18), 710 µm (No. 25),
500 µm (No. 35), 355 µm (No. 45), 250 µm (No. 60) and 180 µm (No. 80). The equivalent sieve numbers,
given for information, are those defined in ASTM E11. Other sieve configurations may be used provided
they give equivalent results. It is desirable to use a set of sieves that have openings that are uniformly
related on a logarithmic scale.
7.1.3.1.1.3 Ventilate
...
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