SIST EN ISO 24234:2005
(Main)Dentistry - Mercury and alloys for dental amalgam (ISO 24234:2004)
Dentistry - Mercury and alloys for dental amalgam (ISO 24234:2004)
This International Standard specifies the requirements and test methods for alloys and for mercury suitable for the preparation of dental amalgam, together with the requirements and test methods for that amalgam and the requirements for packaging and marking. It is applicable to alloys supplied in the form of either a powder in bulk, or a powder compressed to form a tablet, or a powder in predosed capsules. It is applicable to dental mercury supplied either in bulk quantities, or in predosed sachets, or in predosed capsules. This International Standard does not exclude the supply of alloy or mercury separately. This International Standard is not applicable to alloys intended for use with liquid metals that are not mercury, nor is it applicable to liquid metal alloys.
Zahnheilkunde - Quecksilber und Legierungen für zahnärztliche Amalgame (ISO 24234:2004)
Diese Internationale Norm legt Anforderungen an und Prüfverfahren für Legierungen und für Quecksilber, die zur Herstellung von zahnärztlichem Amalgam geeignet sind, zusammen mit den Anforderungen und Prüfverfahren für dieses Amalgam sowie die Anforderungen an die Verpackung und Kennzeichnung fest.
Sie gilt für Legierungen, die als loses Pulver, als Pulver, das in Tablettenform gepresst wurde, oder als Pulver in vordosierten Kapseln geliefert werden.
Sie gilt für dentales Quecksilber, das in losen Mengen oder in vordosierten Kapseln geliefert wird.
Diese Internationale Norm schließt Legierungen oder Quecksilber, die getrennt geliefert werden, nicht aus.
Diese Internationale Norm gilt nicht für Legierungen, die für die Verwendung mit flüssigen Metallen, die kein Quecksilber sind, vorgesehen sind, und gilt auch nicht für flüssige Metalllegierungen.
Art dentaire - Mercure et alliages pour amalgame dentaire (ISO 24234:2004)
L'ISO 24234:2004 spécifie les exigences et les méthodes d'essai applicables aux alliages et au mercure utilisés dans la préparation des amalgames dentaires, les exigences et les méthodes d'essai de l'amalgame lui-même et les exigences d'emballage et de marquage correspondantes.
Elle est applicable aux alliages livrés sous forme de poudre en vrac, de poudre compressée en tablettes ou de poudre en capsules prédosées.
Elle est applicable au mercure à usage dentaire livré en vrac, en sachets prédosés ou en capsules prédosées.
L'ISO 24234:2004 n'exclut pas la fourniture d'alliage ou de mercure séparément.
L'ISO 24234:2004 n'est pas applicable aux alliages destinés à l'usage avec des métaux liquides autres que le mercure ni aux alliages métalliques liquides.
Zobozdravstvo - Živo srebro in zlitine za zobni amalgam (ISO 24234:2004)
Ta mednarodni standard določa zahteve in preskusne metode za zlitine in živo srebro, primerne za pripravo zobnega amalgama, skupaj z zahtevami in preskusnimi metodami za ta amalgam ter zahtevami za pakiranje in označevanje. Velja za zlitine, ki se dobavljajo v obliki praška v razsutem stanju, praška, stisnjenega v tableto, ali praška v predodmerjenih kapsulah. Velja za živo srebro za zobozdravstvo, ki se dobavlja v razsutem stanju, v predodmerjenih vrečkah ali predodmerjenih kapsulah. Ta mednarodni standard ne izključuje ločene dobave zlitine in živega srebra. Ta mednarodni standard ne velja za zlitine, ki se uporabljajo s tekočimi kovinami, ki niso živo srebro, in ne velja za tekoče kovinske zlitine.
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
SIST EN ISO 24234:2005
01-marec-2005
1DGRPHãþD
SIST EN 21560:2000
Zobozdravstvo - Živo srebro in zlitine za zobni amalgam (ISO 24234:2004)
Dentistry - Mercury and alloys for dental amalgam (ISO 24234:2004)
Zahnheilkunde - Quecksilber und Legierungen für zahnärztliche Amalgame (ISO
24234:2004)
Art dentaire - Mercure et alliages pour amalgame dentaire (ISO 24234:2004)
Ta slovenski standard je istoveten z: EN ISO 24234:2004
ICS:
11.060.10 =RERWHKQLþQLPDWHULDOL Dental materials
SIST EN ISO 24234:2005 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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SIST EN ISO 24234:2005
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SIST EN ISO 24234:2005
EUROPEAN STANDARD
EN ISO 24234
NORME EUROPÉENNE
EUROPÄISCHE NORM
October 2004
ICS 11.060.10 Supersedes EN 21560:1991
English version
Dentistry - Mercury and alloys for dental amalgam (ISO
24234:2004)
Art dentaire - Mercure et alliages pour amalgame dentaire Zahnheilkunde - Quecksilber und Legierungen für
(ISO 24234:2004) zahnärztliche Amalgame (ISO 24234:2004)
This European Standard was approved by CEN on 16 August 2004.
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 Central Secretariat 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 Central Secretariat has the same status as the official
versions.
CEN members are the national standards bodies of Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France,
Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia,
Slovenia, Spain, Sweden, Switzerland and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: rue de Stassart, 36 B-1050 Brussels
© 2004 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 24234:2004: E
worldwide for CEN national Members.
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SIST EN ISO 24234:2005
EN ISO 24234:2004 (E)
Foreword
This document (EN ISO 24234:2004) has been prepared by Technical Committee ISO/TC 106
"Dentistry" in collaboration with Technical Committee CEN/TC 55 "Dentistry", 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 April 2005, and conflicting national
standards shall be withdrawn at the latest by April 2005.
This document supersedes EN 21560:1991.
According to the CEN/CENELEC Internal Regulations, the national standards organizations of
the following countries are bound to implement this European Standard: Austria, Belgium,
Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary,
Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland,
Portugal, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.
Endorsement notice
The text of ISO 24234:2004 has been approved by CEN as EN ISO 24234:2004 without any
modifications.
2
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SIST EN ISO 24234:2005
INTERNATIONAL ISO
STANDARD 24234
First edition
2004-10-15
Dentistry — Mercury and alloys for dental
amalgam
Art dentaire — Mercure et alliages pour amalgame dentaire
Reference number
ISO 24234:2004(E)
©
ISO 2004
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SIST EN ISO 24234:2005
ISO 24234:2004(E)
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ii © ISO 2004 – All rights reserved
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SIST EN ISO 24234:2005
ISO 24234:2004(E)
Contents Page
Foreword. iv
Introduction . v
1 Scope. 1
2 Normative references . 1
3 Terms and definitions. 2
4 Requirements . 3
4.1 General. 3
4.2 Chemical composition of the alloy. 3
4.3 Biocompatibility . 4
4.4 Foreign material and large particles in the alloy powder . 4
4.5 Contamination of the mercury by oil, water and foreign material . 4
4.6 Purity of mercury — Free pouring. 4
4.7 Variability of preproportioned masses . 4
4.8 Properties of the amalgam. 5
4.9 Appearance of the mixed amalgam before setting. 5
5 Sampling . 6
6 Test methods. 6
6.1 Chemical composition of the alloy. 6
6.2 Foreign material and large particles in the alloy powder . 6
6.3 Contamination of the mercury by oil, water or foreign material . 7
6.4 Free-pouring of mercury . 8
6.5 Determination of the variability of preproportioned masses . 8
6.6 Preparation of test specimens to determine compliance with the requirements for creep,
dimensional change and compressive strength . 9
6.7 Determination of creep. 14
6.8 Determination of dimensional change during hardening. 14
6.9 Determination of compressive strength.15
6.10 Appearance of the mixed amalgam before setting. 15
7 Marking, labelling and packaging . 16
7.1 Packaging . 16
7.2 Marking. 16
7.3 Manufacturer’s instructions. 17
Annex A (normative) Determination of immersion corrosion for dental amalgam . 19
Annex B (normative) Potentiostatic determination of corrosion for dental amalgam . 24
Bibliography . 28
Table 1 — Requirements for chemical composition of the alloy . 4
Table 2 — Properties of amalgam . 5
Table 3 — Schedule for the preparation of test specimens .13
Table B.1 — Potential settings for different reference electrodes and temperatures of
the reference electrodes. 27
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SIST EN ISO 24234:2005
ISO 24234:2004(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.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International Standards
adopted by the technical committees are circulated to the member bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the member bodies casting a vote.
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.
ISO 24234 was prepared by Technical Committee ISO/TC 106, Dentistry, Subcommittee SC 1, Filling and
restorative materials.
This International Standard cancels and replaces ISO 1559:1995, ISO 1559:1995/Cor.1:1997 and
ISO 1560:1985.
A number of technical revisions have been made as improvements or as a consequence of combining the
International Standards that have been replaced.
The scope of this International Standard applies to alloys for dental amalgam and dental mercury,
whether provided individually or together.
The clause permitting a deviation in the composition of alloys for amalgam has been removed.
Guidance on biocompatibility assessment has been introduced.
A limit on the presence of large alloy particles has been introduced.
The requirement for loss of mercury from predosed capsules has been removed, since it is a requirement
in ISO 13897.
The values for the requirements on creep, dimensional change and compressive strength at 1 h have
been revised.
The criterion for compliance with the compressive strength requirements has been revised.
Provisions for packaging and marking have been revised.
Markings required for mercury safety warnings and precautions have been revised to conform to
ISO requirements and the United Nations Globally Harmonized System of Classification and Labelling of
Chemicals (GHS). They are no longer dependent upon national or regional requirements.
Procedures for corrosion testing have been added as normative annexes.
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SIST EN ISO 24234:2005
ISO 24234:2004(E)
Introduction
Dental amalgam alloy and mercury are the essential and only components of dental amalgam restorative
material. This International Standard combines the requirements and the test methods for the alloy with those
for the mercury in a single standard, of which this is the first edition. Formerly, these were contained in two
separate standards.
Specific qualitative and quantitative requirements for freedom from biological hazard are not included in this
International Standard, but it is recommended that, in assessing possible biological hazards, reference be
made to ISO 10993-1 and ISO 7405.
To enhance the safety of dentists and support staff, it would have been preferred to limit the scope solely to
the use of predosed capsules of alloy and mercury. It is, however, recognised and accepted that both
amalgam alloy and mercury are supplied in bulk form in some parts of the world where, for economic reasons,
this is necessary for the provision of dental treatment. Therefore requirements for these products are included
in this International Standard. Safety precautions relating to marking, labelling and packaging have been
strengthened in this revision.
Inclusion of a requirement for corrosion resistance was considered, using the procedures for corrosion testing
given in ISO/TS 17576. However it was decided that the data available were insufficient to justify a corrosion
requirement in this International Standard, and as a consequence the test methods alone are given, as
normative annexes. A requirement for the corrosion resistance will be set and incorporated at the earliest
possible date.
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SIST EN ISO 24234:2005
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SIST EN ISO 24234:2005
INTERNATIONAL STANDARD ISO 24234:2004(E)
Dentistry — Mercury and alloys for dental amalgam
WARNING — The use of this International Standard may involve hazardous materials, operations and
equipment. This International Standard does not purport to address all of the safety problems
associated with its use. It is the responsibility of the user of this International Standard to establish
appropriate safety and health practices and to determine the applicability or regulatory limitations
prior to use.
1 Scope
This International Standard specifies the requirements and test methods for alloys and for mercury suitable for
the preparation of dental amalgam, together with the requirements and test methods for that amalgam and the
requirements for packaging and marking.
It is applicable to alloys supplied in the form of either a powder in bulk, or a powder compressed to form a
tablet, or a powder in predosed capsules.
It is applicable to dental mercury supplied either in bulk quantities, or in predosed sachets, or in predosed
capsules.
This International Standard does not exclude the supply of alloy or mercury separately.
This International Standard is not applicable to alloys intended for use with liquid metals that are not mercury,
nor is it applicable to liquid metal alloys.
2 Normative references
The following referenced documents are indispensable for the application 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 286-2, ISO system of limits and fits — Part 2: Table of standard tolerance grades and limit deviations for
holes and shafts
ISO 3310-1, Test sieves — Technical requirements for testing — Part 1: Test sieves of metal wire cloth
ISO 3585, Borosilicate glass 3.3 — Properties
ISO 3696:1987, Water for analytical laboratory use — Specification and test methods
ISO 3864-2, Graphical symbols — Safety colours and safety signs — Part 2: Design principles for product
safety labels
ISO 4793:1980, Laboratory sintered (fritted) filters — Porosity grading, classification and designation
ISO 6344-1:1998, Coated abrasives — Grain size analysis — Part 1: Grain size distribution test
ISO 7488, Dental amalgamators
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SIST EN ISO 24234:2005
ISO 24234:2004(E)
ISO 8282, Dental equipment — Mercury and alloy mixers and dispensers
ISO 13565-2, Geometrical Product Specifications (GPS) — Surface texture: Profile method; Surfaces having
stratified functional properties — Part 2: Height characterization using the linear material ratio curve
ISO 13897, Dentistry — Amalgam capsules
Globally Harmonized System of Classification and Labelling of Chemicals (GHS). United Nations, New York
and Geneva, 2003, ISBN 92-1-116840-6
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
alloy for dental amalgam
alloy in fine particles, composed mainly of silver, tin and copper, which when mixed with mercury produces a
dental amalgam
3.2
predosed capsule
capsule, as-supplied, containing measured amounts of alloy powder and mercury for dental amalgam,
separated in such a way that premature combination is prevented
NOTE The separating barrier is broken immediately prior to mixing or breaks during mixing, allowing the alloy and
mercury to come into contact.
3.3
amalgam alloy tablet
quantity of dental amalgam alloy powder that has been compressed to form a single entity for the purpose of
providing a predosed quantity of the alloy.
NOTE During mixing, the tablet is intended to break apart, forming a fine powder.
3.4
tailing
phenomenon which occurs when mercury that contains impurities moves over a clean surface, tending to
leave behind a portion of the liquid, forming an elongated tail as if it were sticking to that surface
3.5
primary container
container or package that is in direct contact with the material
3.6
dental mercury sachet
measured quantity of dental mercury supplied in a sachet that is suitable for a reusable mixing capsule
NOTE The sachet is broken immediately prior to mixing, or breaks during mixing, allowing the mercury to come into
contact with the alloy
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SIST EN ISO 24234:2005
ISO 24234:2004(E)
4 Requirements
4.1 General
4.1.1 If the alloy is supplied as a powder in bulk, the product shall comply with
requirements 4.2, 4.3, 4.4, 4.8, 4.9, and
packaging requirement 7.1, and
marking requirements 7.2.1 a) to f), h) to j) and 7.3.
4.1.2 If the alloy is supplied as tablets, the product shall comply with
requirements 4.2, 4.3, 4.4, 4.7, 4.8, 4.9, and
packaging requirement 7.1, and
marking requirements 7.2.1 a) to f), h) to j) and 7.3.
4.1.3 If the alloy and the dental mercury are supplied together in predosed capsules, the product shall
comply with
all requirements.
4.1.4 If the dental mercury is supplied as mercury in bulk, the product shall comply with
requirements 4.3, 4.5, 4.6, and
packaging requirement, 7.1 and
marking requirements 7.2.1 a) to d), f) and g), 7.2.2 and 7.3.2.
4.1.5 If the dental mercury is supplied in dental mercury sachets, the product shall comply with
requirements 4.3, 4.5, 4.6 and 4.7, and
packaging requirement 7.1, and
marking requirements 7.2.1 a) to d), f) and g), 7.2.2 and 7.3.2.
4.2 Chemical composition of the alloy
The manufacturer shall declare every element that is present in a concentration greater than or equal to 0,1 %
(mass fraction). All alloying elements in concentrations greater than 0,5 % (mass fraction) shall be given by
name, with values rounded to the nearest percentage (mass fraction). Alloying elements that are present in
concentrations between 0,1 % and 0,5 % (mass fraction) shall be named without a percentage value.
Test in accordance with 6.1.
The chemical composition shall comply with Table 1.
The total concentration of other elements shall not exceed 0,1 % (mass fraction).
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SIST EN ISO 24234:2005
ISO 24234:2004(E)
Table 1 — Requirements for chemical composition of the alloy
Mass fraction
Element
%
silver W 40
tin u 32
copper u 30
indium u 5
palladium u 1
platinum u 1
zinc u 2
mercury u 3
4.3 Biocompatibility
See the Introduction for guidance on biocompatibility.
4.4 Foreign material and large particles in the alloy powder
When tested in accordance with 6.2, no more than five particles of foreign material shall be found on the sieve.
The mass of alloy particles that remain on the sieve shall not exceed 0,1 % (mass fraction) of the sample used
for this test.
4.5 Contamination of the mercury by oil, water and foreign material
When the procedure in 6.3.1 and 6.3.2 is followed, the dental mercury shall be visibly free from contamination
by oil, water or foreign material and shall have a bright mirror-like surface that does not form a scum in air
within the specified period.
If the dental mercury is supplied in bulk form and does not have a bright mirror-like surface, then the
procedures in 6.3.3 and 6.3.4 shall be carried out. After this procedure has been completed, the dental
mercury shall have a bright, mirror-like surface that does not form a scum in air within the specified period.
4.6 Purity of mercury — Free pouring
When tested according to the procedure in 6.4, the mercury shall pour freely and completely without tailing.
Small droplets not coalesced with the bulk after shaking shall not be construed as evidence of non-compliance
with this subclause.
4.7 Variability of preproportioned masses
4.7.1 For products supplied as predosed capsules
The coefficients of variation of the masses of the dental alloy and the dental mercury in the capsules shall not
exceed 1,5 %, when tested in accordance with 6.5.1.
The arithmetic means of the masses of both alloy and mercury shall be within ± 2,0 % (mass fraction) of the
manufacturer’s stated masses, when tested in accordance with 6.5.1.
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SIST EN ISO 24234:2005
ISO 24234:2004(E)
4.7.2 For products supplied as tablets
The coefficient of variation of the mass of the dental alloy tablets shall not exceed 1,5 %, when tested in
accordance with 6.5.2.
The arithmetic mean of the mass of the alloy tablet shall be within ± 2,0 % (mass fraction) of the
manufacturer’s stated mass, when tested in accordance with 6.5.2.
4.7.3 For products supplied as dental mercury sachets
The coefficient of variation of the mass of the dental mercury in the sachet shall not exceed 1,5 %, when
tested in accordance with 6.5.3.
The arithmetic mean of the mass of the dental mercury in the sachet shall be within ± 2,0 % (mass fraction) of
the manufacturer’s stated mass, when tested in accordance with 6.5.3.
4.8 Properties of the amalgam
4.8.1 General
When tested in accordance with 6.7 to 6.9, the material shall comply with the requirements given in Table 2.
Table 2 — Properties of amalgam
Maximum Permitted dimensional Minimum compressive strength Minimum compressive strength
creep change during hardening at 1 h at 24 h
% % MPa MPa
2,0 –0,10 to +0,20 80 300
4.8.2 Creep
When tested in accordance with 6.7, either three out of three, or four out of five specimens shall meet the
requirement in Table 2.
4.8.3 Dimensional changes during hardening
When tested in accordance with 6.8, at least four out of five specimens shall meet the requirement in Table 2.
4.8.4 Compressive strength at 1 h
When tested in accordance with 6.9, at least four out of five specimens, or eight out of ten specimens shall
meet the requirement in Table 2.
4.8.5 Compressive strength at 24 h
When tested in accordance with 6.9, at least four out of five specimens, or eight out of ten specimens shall
meet the requirement in Table 2.
4.9 Appearance of the mixed amalgam before setting
When the alloy and mercury are mixed according to the manufacturer’s instructions and tested in accordance
with 6.10, it shall form a coherent plastic mass, with a shiny surface.
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SIST EN ISO 24234:2005
ISO 24234:2004(E)
5 Sampling
At least 50 g of alloy of the same lot in packages produced for retail shall be procured.
At least 50 g of mercury of the same lot in packages produced for retail shall be procured.
6 Test methods
6.1 Chemical composition of the alloy
Use a recognized, instrumented analytical procedure that has adequate sensitivity to determine the
composition of the alloy for the elements declared by the manufacturer in compliance with 4.2. Inductively
coupled plasma spectroscopy (ICP) is a suitable example.
For other elements that are detected at levels greater than 0,01 % (mass fraction), but are not alloying
elements, sum their masses and report the sum as the “mass fraction of other elements”.
6.2 Foreign material and large particles in the alloy powder
For alloy supplied as a powder in bulk, weigh a (10,0 ± 0,1) g sample to an accuracy of ± 0,001 g and record
(m ).
s
For alloy supplied in predosed capsules, select and open a sufficient number of capsules to obtain a
(10,0 ± 0,1) g sample of alloy. Weigh this sample to an accuracy of 0,001 g and record (m ).
s
For alloy supplied as tablets, place a tablet in a reusable capsule that complies with ISO 13897. Break the
tablet in the capsule to its constituent powder particles using a mechanical amalgamator that complies with
ISO 7488, set at the machine setting and at one-half the time recommended by the alloy manufacturer for
mixing the alloy and dental mercury in accordance with 7.3.1. If the manufacturer’s recommendations include
any other action to break-up the tablet (e.g. use of a pestle), incorporate this at the appropriate point. Repeat
this using a sufficient number of tablets to obtain (10,0 ± 0,1) g of powder. Weigh this sample to an accuracy
of 0,001 g and record (m ).
s
Place the powder sample on a sieve of mesh size 150 µm and diameter 76 mm. The sieve shall conform to
ISO 3310-1. Hold the sieve assembly (consisting of collecting pan, sieve and cover) in one hand and tap it
gently against the other hand at a rate of approximately twice a second for 120 s. Inspect the sieve at a
magnification of × 10 for any remaining foreign material and alloy particles. Record the number of foreign
material particles.
Remove any foreign material and then transfer the remaining alloy particles to a balance. Weigh to an
accuracy of 0,001 g and record (m ). Calculate the percentage (mass fraction) of alloy that occurs in particles
r
that have a size greater than 150 µm, as follows:
m
r
×=100 w (%) (1)
m
s
where
m is the mass of alloy particles remaining on the sieve;
r
m is the mass of the powder sample;
s
w is the percentage (mass fraction) of alloy particles greater than 150 µm in diameter.
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SIST EN ISO 24234:2005
ISO 24234:2004(E)
6.3 Contamination of the mercury by oil, water or foreign material
6.3.1 Preparation of the sample
6.3.1.1 Dental mercury supplied in bulk form
Take a clean small flask made of borosilicate or similar glass (100 ml is a suitable capacity). Rinse with water
(in accordance with ISO 3696:1987, grade 2) then with 3 m
...
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