Cereals, pulses and by-products - Determination of ash yield by incineration (ISO 2171:2023)

This document specifies a method for determining the ash yield by cereals, pulses and their milled products intended for human consumption. The source materials and products covered are:
a)    grains of cereals;
b)    flours and semolinas;
c)     other milling products (bran and high bran content products, shorts);
d)    mixed cereal flours (mixes);
e)    cereal by-products other than c) (such as wheat gluten, maize grits, broken rice kernels);
f)     pulses and their by-products (flour).
This document does not apply to starches and starch derivatives (see ISO 3593), to products intended for animal feeding stuffs (see ISO 5984) or to seeds.

Getreide, Hülsenfrüchte und Nebenprodukte - Bestimmung des Aschegehalts durch Verbrennung (ISO 2171:2023)

Dieses Dokument legt ein Verfahren zur Bestimmung des Aschegehalts von Getreide, Hülsenfrüchten und deren Mahlerzeugnissen fest, die für die menschliche Ernährung vorgesehen sind. Zu diesen Ausgangsstoffen und Erzeugnissen gehören:
a)   Getreidekörner;
b)   Mehle und Grieße;
c)   sonstige Mahlerzeugnisse (Kleie und Produkte mit hohem Kleienanteil, feine Kleie);
d)   gemischte Getreidemehle (Mehlmischungen);
e)   andere Getreide-Nebenprodukte als c) (wie z. B. Weizengluten, Maisgrütze, Bruchreiskörner);
f)   Hülsenfrüchte und deren Nebenprodukte (Mehl).
Dieses Dokument ist nicht anwendbar für Stärke und Stärkederivate (siehe ISO 3593), Produkte, die zur Tierfütterung vorgesehen sind (siehe ISO 5984) oder für Samen.

Céréales, légumineuses et produits dérivés - Détermination du taux de cendres par incinération (ISO 2171:2023)

Le présent document spécifie une méthode de détermination du taux de cendres dans les céréales, les légumineuses et leurs produits de mouture destinés à l’alimentation humaine. Les matériaux et produits sources sont:
a)     les graines de céréales;
b)    les farines et les semoules;
c)     les autres produits de mouture (sons et produits à forte teneur en son, remoulages);
d)    les farines de céréales composées;
e)     les produits dérivés des céréales autres que c) (tels que le gluten de blé, le gruau de maïs, les brisures de riz);
f)      les légumineuses et leurs produits dérivés (farine).
Le présent document ne s’applique ni aux amidons et produits dérivés des amidons (voir l’ISO 3593), ni aux produits destinés à l’alimentation animale (voir l’ISO 5984) ni aux semences.

Žita, stročnice in stranski proizvodi - Določevanje deleža pepela po sežigu (ISO 2171:2023)

Ta dokument določa metodo za določanje pridobljene količine pepela za žita, stročnice in njihove mlete proizvode, namenjene za prehrano ljudi. Zajeti so naslednji izvorni materiali in proizvodi:
a)    žitno zrnje;
b)    moke in zdrobi;
c)     drugi mlevski izdelki (otrobi in izdelki z visoko vsebnostjo otrobov, stranski produkti);
d)    mešane žitne moke (mešanice);
e)    stranski proizvodi žit, ki niso c) (npr. pšenični gluten, koruzni zdrob, zdrobljena riževa zrna);
f)     stročnice in njihovi stranski proizvodi (moka).
Ta dokument se ne uporablja za škrob in škrobove derivate (glej standard ISO 3593), izdelke, namenjene za živalsko krmo (glej standard ISO 5984), ali semena.

General Information

Status
Published
Publication Date
07-Mar-2023
Current Stage
6060 - Definitive text made available (DAV) - Publishing
Start Date
08-Mar-2023
Completion Date
08-Mar-2023

Relations

Buy Standard

Standard
EN ISO 2171:2023
English language
19 pages
sale 10% off
Preview
sale 10% off
Preview
e-Library read for
1 day
Draft
prEN ISO 2171:2020
English language
15 pages
sale 10% off
Preview
sale 10% off
Preview
e-Library read for
1 day

Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN ISO 2171:2023
01-maj-2023
Žita, stročnice in stranski proizvodi - Določevanje deleža pepela po sežigu (ISO
2171:2023)
Cereals, pulses and by-products - Determination of ash yield by incineration (ISO
2171:2023)
Getreide, Hülsenfrüchte und Nebenprodukte - Bestimmung des Aschegehalts durch
Verbrennung (ISO 2171:2023)
Céréales, légumineuses et produits dérivés - Détermination du taux de cendres par
incinération (ISO 2171:2023)
Ta slovenski standard je istoveten z: EN ISO 2171:2023
ICS:
67.060 Žita, stročnice in proizvodi iz Cereals, pulses and derived
njih products
SIST EN ISO 2171:2023 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

---------------------- Page: 1 ----------------------
SIST EN ISO 2171:2023

---------------------- Page: 2 ----------------------
SIST EN ISO 2171:2023


EN ISO 2171
EUROPEAN STANDARD

NORME EUROPÉENNE

March 2023
EUROPÄISCHE NORM
ICS 67.060 Supersedes EN ISO 2171:2010
English Version

Cereals, pulses and by-products - Determination of ash
yield by incineration (ISO 2171:2023)
Céréales, légumineuses et produits dérivés - Getreide, Hülsenfrüchte und Nebenprodukte -
Détermination du taux de cendres par incinération Bestimmung des Aschegehalts durch Verbrennung (ISO
(ISO 2171:2023) 2171:2023)
This European Standard was approved by CEN on 24 February 2023.

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, Türkiye 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
© 2023 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 2171:2023 E
worldwide for CEN national Members.

---------------------- Page: 3 ----------------------
SIST EN ISO 2171:2023
EN ISO 2171:2023 (E)
Contents Page
European foreword . 3

2

---------------------- Page: 4 ----------------------
SIST EN ISO 2171:2023
EN ISO 2171:2023 (E)
European foreword
This document (EN ISO 2171:2023) has been prepared by Technical Committee ISO/TC 34 "Food
products" in collaboration with Technical Committee CEN/TC 338 “Cereal and cereal products” the
secretariat of which is held by AFNOR.
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 2023, and conflicting national standards
shall be withdrawn at the latest by September 2023.
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 2171:2010.
Any feedback and questions on this document should be directed to the users’ national standards
body/national committee. A complete listing of these bodies can be found on the CEN website.
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, Türkiye and the
United Kingdom.
Endorsement notice
The text of ISO 2171:2023 has been approved by CEN as EN ISO 2171:2023 without any modification.

3

---------------------- Page: 5 ----------------------
SIST EN ISO 2171:2023

---------------------- Page: 6 ----------------------
SIST EN ISO 2171:2023
INTERNATIONAL ISO
STANDARD 2171
Fifth edition
2023-02
Cereals, pulses and by-products —
Determination of ash yield by
incineration
Céréales, légumineuses et produits dérivés — Détermination du taux
de cendres par incinération
Reference number
ISO 2171:2023(E)
© ISO 2023

---------------------- Page: 7 ----------------------
SIST EN ISO 2171:2023
ISO 2171:2023(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2023
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
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: +41 22 749 01 11
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii
  © ISO 2023 – All rights reserved

---------------------- Page: 8 ----------------------
SIST EN ISO 2171:2023
ISO 2171:2023(E)
Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Principle . 2
5 Reagents . 2
6 Apparatus . 2
7 Sampling . 3
8 Preparation of the test sample. 3
9 Procedure .3
9.1 Incineration temperatures . 3
9.2 Determination of the moisture content . 3
9.3 Preparation of the ashing dishes . 4
9.4 Preparation of the test portion . 4
9.5 Pre-ashing . 4
9.6 Ashing . 4
9.7 Number of determinations . 5
10 Expression of results . 5
11 Precision . 5
11.1 Interlaboratory tests . 5
11.2 Repeatability, r. 5
11.3 Reproducibility, R . 6
11.4 Critical difference . 6
11.4.1 Comparison of two groups of measurements in one laboratory . 6
11.4.2 Comparison of two groups of measurements in two laboratories . 6
11.5 Uncertainty, U . 6
12 Test report . 7
Annex A (informative) Results of interlaboratory tests . 8
Annex B (informative) Practical application of repeatability and reproducibility limits .11
Bibliography .12
iii
© ISO 2023 – All rights reserved

---------------------- Page: 9 ----------------------
SIST EN ISO 2171:2023
ISO 2171:2023(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 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 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/foreword.html.
This document was prepared by Technical Committee ISO/TC 34, Food products, Subcommittee SC 4,
Cereals and pulses, in collaboration with the European Committee for Standardization (CEN) Technical
Committee CEN/TC 338, Cereal and cereal products, in accordance with the Agreement on technical
cooperation between ISO and CEN (Vienna Agreement).
This fifth edition cancels and replaces the fourth edition (ISO 2171:2007), which has been technically
revised. The main changes are as follows:
— the Scope has been updated;
— silica gel has been added as a desiccant (5.2);
— the use of platinum dishes and a temperature of incineration of 900 °C for the flour analysis has
replaced a choice of a temperature between 900 °C and 550 °C (see Table 1);
— the interlaboratory critical difference (C ) has been updated in 11.4.2.
D,R
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.
iv
  © ISO 2023 – All rights reserved

---------------------- Page: 10 ----------------------
SIST EN ISO 2171:2023
INTERNATIONAL STANDARD ISO 2171:2023(E)
Cereals, pulses and by-products — Determination of ash
yield by incineration
1 Scope
This document specifies a method for determining the ash yield by cereals, pulses and their milled
products intended for human consumption. The source materials and products covered are:
a) grains of cereals;
b) flours and semolinas;
c) other milling products (bran and high bran content products, shorts);
d) mixed cereal flours (mixes);
e) cereal by-products other than c) (such as wheat gluten, maize grits, broken rice kernels);
f) pulses and their by-products (flour).
This document does not apply to starches and starch derivatives (see ISO 3593), to products intended
for animal feeding stuffs (see ISO 5984) or to seeds.
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 712, Cereals and cereal products — Determination of moisture content — Reference method
ISO 6540, Maize — Determination of moisture content (on milled grains and on whole grains)
ISO 24557, Pulses — Determination of moisture content — Air-oven method
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1
ash
incombustible residue obtained after incineration
Note 1 to entry: This is according to the method given in this document.
3.2
critical difference
difference between two averaged values obtained from two test results under repeatability conditions
1
© ISO 2023 – All rights reserved

---------------------- Page: 11 ----------------------
SIST EN ISO 2171:2023
ISO 2171:2023(E)
4 Principle
A test portion is incinerated until combustion of organic matter is complete, then the residue obtained is
weighed. The residue obtained is flaky after incineration at (550 ± 10) °C and vitrified after incineration
at (900 ± 25) °C.
In general, products containing salts (e.g. sodium chloride, pyrophosphate) shall be incinerated at
(550 ± 10) °C.
5 Reagents
Unless stated otherwise, use only reagents of recogni
...

SLOVENSKI STANDARD
oSIST prEN ISO 2171:2020
01-oktober-2020
Žita, stročnice in stranski proizvodi - Določanje izkoristka pepela po sežiganju
(ISO/DIS 2171:2020)
Cereals, pulses and by-products - Determination of ash yield by incineration (ISO/DIS
2171:2020)
Getreide, Hülsenfrüchte und Nebenprodukte - Bestimmung des Aschegehalts durch
Verbrennung (ISO/DIS 2171:2020)
Céréales, légumineuses et produits dérivés - Dosage du taux de cendres par
incinération (ISO/DIS 2171:2020)
Ta slovenski standard je istoveten z: prEN ISO 2171
ICS:
67.060 Žita, stročnice in proizvodi iz Cereals, pulses and derived
njih products
oSIST prEN ISO 2171:2020 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

---------------------- Page: 1 ----------------------
oSIST prEN ISO 2171:2020

---------------------- Page: 2 ----------------------
oSIST prEN ISO 2171:2020
DRAFT INTERNATIONAL STANDARD
ISO/DIS 2171
ISO/TC 34/SC 4 Secretariat: SAC
Voting begins on: Voting terminates on:
2020-07-27 2020-10-19
Cereals, pulses and by-products — Determination of ash
yield by incineration
Céréales, légumineuses et produits dérivés — Dosage du taux de cendres par incinération
ICS: 67.060
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 2171:2020(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 2020

---------------------- Page: 3 ----------------------
oSIST prEN ISO 2171:2020
ISO/DIS 2171:2020(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
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: +41 22 749 01 11
Fax: +41 22 749 09 47
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii © ISO 2020 – All rights reserved

---------------------- Page: 4 ----------------------
oSIST prEN ISO 2171:2020
ISO/DIS 2171:2020(E)

Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Principle . 1
5 Reagents . 2
6 Apparatus . 2
7 Sampling . 2
8 Preparation of the test sample . 3
9 Procedure. 3
9.1 Determination of the moisture content . 3
9.2 Preparation of the ashing dishes . 3
9.3 Preparation of the test portion . 3
9.4 Pre-ashing . 4
9.5 Ashing . 4
9.6 Number of determinations . 4
10 Expression of results . 4
11 Precision . 5
11.1 Interlaboratory tests . 5
11.2 Repeatability (r) . 5
11.3 Reproducibility (R) . 5
11.4 Critical difference. 6
11.4.1 Comparison of two groups of measurements in one laboratory . 6
11.4.2 Comparison of two groups of measurements in two laboratories . 6
11.5 Uncertainty (U) . 6
12 Test report . 6
Annex A (informative) Results of interlaboratory tests. 8
Annex B (informative) Practical application of repeatability and reproducibility limits .10
Bibliography .11
© ISO 2020 – All rights reserved iii

---------------------- Page: 5 ----------------------
oSIST prEN ISO 2171:2020
ISO/DIS 2171:2020(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/ 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/ Food products, Subcommittee SC 4, Cereals and pulses.
This fifth edition cancels and replaces the fourth edition (ISO 2171:2007), which has been technically
revised. The main changes in the ISO 2171, determination of ash yield by incineration are, the use of
platinum dishes and a temperature of incineration of 900 °C for the flour analysis instead of a choice
between  900°C and 550°C (cf. tableau 1) and all the normative references were updated.
iv © ISO 2020 – All rights reserved

---------------------- Page: 6 ----------------------
oSIST prEN ISO 2171:2020
DRAFT INTERNATIONAL STANDARD ISO/DIS 2171:2020(E)
Cereals, pulses and by-products — Determination of ash
yield by incineration
1 Scope
This International Standard specifies a method for determining the ash yielded by cereals, pulses and
their milled products intended for human consumption. The source materials and products covered are:
a) grains of cereals;
b) flours and semolinas;
c) milled products (bran and high bran content products, shorts);
d) mixed cereal flours (mixes);
e) cereal by-products other than milled products;
f) pulses and their by-products.
This International Standard is not applicable to starches and starch derivatives (see ISO 3593), to
products intended for animal feeding stuffs (see ISO 5984), or to seeds.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated
references, only the cited edition applies. For undated references, the latest edition of the referenced
document (including any amendments) applies.
ISO 712, Cereals and cereal products — Determination of moisture content — Reference method
ISO 6540, Maize — Determination of moisture content (on milled grains and on whole grains)
ISO 24557, Pulses — Determination of moisture content — Air-oven method
ISO 12099, Animal feeding stuffs, cereals and milled cereal products — Guidelines for the application of
near infrared spectrometry
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
ash
incombustible residue obtained after incineration according to the method given in this International
Standard
4 Principle
A test portion is incinerated until combustion of organic matter is complete, then the residue obtained
is weighed. The residue obtained is flaky after incineration at (550 °C ± 10°C) and vitrified after
incineration at (900 °C ± 25°C).
In general, products containing salts (e.g. sodium chloride, pyrophosphate) shall be incinerated at
(550 ± 10) °C.
© ISO 2020 – All rights reserved 1

---------------------- Page: 7 ----------------------
oSIST prEN ISO 2171:2020
ISO/DIS 2171:2020(E)

5 Reagents
Unless stated otherwise, use only reagents of recognized analytical quality and distilled or
demineralized water or water of equivalent purity.
5.1 Hydrochloric acid, aqueous solution or ready-to-use solution of one part by volume of HCl (35 %
volume fraction) and one part by volume of water.
5.2 Purified diphosphorus pentoxide (P O ).
4 10
5.3 Ethanol.
6 Apparatus
6.1 Grinding mill, easy to clean and having as little dead space as possible, and ensuring rapid,
uniform grinding.
6.2 Ashing dish, of capacity not less than 20 ml, rectangular or round shape, flat-bottomed and having
2
a surface area of not less than 12 cm . Suitable materials for the ashing dish which do not deteriorate
under test conditions at the temperature of operation are:
a) at 900 °C — platinum rhodium;
b) at 550 °C — quartz or silica.
In both cases, the material used shall allow compliance with the precision values.
The dishes shall be cleaned by complete immersion for at least 1 h in aqueous hydrochloric acid (5.1),
then rinsed with running water and then with distilled water.
After rinsing, the quartz or silica dishes shall be dried in an oven (6.7) at a temperature and for a period
sufficient to eliminate water.
6.3 Electrically heated muffle furnace, provided with a refractory coating, with a control system,
capable of reaching and maintaining the temperatures of (900 ± 25) °C or at (550 ± 10) °C.
It is recommended to check the thermal geography of the oven by filling it with capsules containing a
control sample in order to determine its degree of possible filling.
When the combustion is done inside the furnace, case of the ashing at 550°C by rise of the temperature,
it is recommended to carry out a sweeping of the chimney of the oven, which clogs more quickly.
6.4 Vacuum desiccator, equipped with a perforated aluminium or porcelain plate, and diphosphorus
pentoxide (5.2) as drying agent.
6.5 Analytic
...

Questions, Comments and Discussion

Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.