prEN 196-17

• Abstract:

  This document describes two equivalent test methods for determining the glass content in Granulated blast furnace Slag (GBS) as constituent for common cement as defined on EN 197-1.; Method A - Method of determining the glass content of GBS by X-ray diffraction.; Method B - Method of determining the glass content of GBS by polarized optical microscopy.; The glass content (or glassy/amorphous phase) in GBS is the fraction of the material that lacks a crystalline structure, having solidified rapidly from the melt in the form of amorphous glass.; It is usually expressed as a percentage (wt%) of the total slag.; In the absence of a product standard or a specification in the product standard, the constituent is tested at the fineness of the intended use.; Furthermore, these test methods are used in manufacturing control of cement constituents for assessing their conformity to the limit indicated in EN 197-1.

• Status: Not Published
• Publication Date: 28-Jun-2028
• ICS: 91.100.10 - Cement. Gypsum. Lime. Mortar
• Technical Committee: CEN/TC 51 - Cement and building limes
• Drafting Committee: CEN/TC 51/WG 15 - Revision of methods of testing cement
• Current Stage: 4020 - Submission to enquiry - Enquiry
• Start Date: 06-Aug-2026
• Due Date: 11-Feb-2027
• Completion Date: 06-Aug-2026
• Ref Project: oSIST prEN 196-17:2026 - Method of testing cement - Part 17: Determination glass content of granulated blast furnace slag as constituent for common cement

Overview

prEN 196-17 is a European draft standard from CEN that defines methods for testing cement, specifically focusing on determining the glass content in Granulated Blast Furnace Slag (GBS) when used as a constituent in common cement, as outlined in EN 197-1. The glass content refers to the amorphous, non-crystalline fraction of GBS, which directly influences cement properties such as reactivity and durability. This standard describes two equivalent laboratory test methods for determining glass content: Method A (X-ray diffraction) and Method B (polarized optical microscopy). These methods support manufacturers, laboratories, and quality control processes to assure conformity with specified limits and regulatory requirements.

Key Topics

• Glass Content in GBS: Quantifies the amorphous phase of GBS, critical for assessing cement performance.
• Method A – X-ray Diffraction (XRD):
  • Utilizes X-ray analysis and Rietveld refinement to determine the ratio of glassy to crystalline phases.
  • Employs direct and indirect quantification methods, including internal and external standards.
  • Highly suitable for labs equipped with XRD instrumentation and trained operators.
• Method B – Polarized Optical Microscopy:
  • Identifies glassy phases based on optical properties under polarized light.
  • Requires sample preparation and skilled microscopic examination.
  • Effective for direct visual assessment and counting of glassy versus crystalline grains.
• Sample Preparation and Testing:
  • Emphasizes careful preparation to avoid altering glass content by excessive grinding.
  • Mandates drying and sieving processes to ensure accurate and representative results.

Applications

• Quality Control of Cement Production: Both methods are integral to manufacturing control, supporting the verification of GBS glass content against specification limits in EN 197-1 for common cements.
• Conformity Assessment: The procedures enable cement producers and laboratories to ensure regulatory compliance and consistent product quality.
• Material Characterization: Accurate determination of glass content helps predict cement hydration behavior and ensures the desired performance in construction applications.
• Research and Development: The methods provide reliable tools for the characterization of raw materials and optimizing cement blends.
• Standardization and Certification: Supports independent third-party testing, documentation, and certification in line with European and national standards.

Related Standards

• EN 197-1: Common cement - Performance assessment and declaration; defines requirements for cement composition, including GBS content.
• EN 196-7: Methods of taking and preparing samples of cement; details sampling protocols relevant for both glass content determination methods.
• EN 196-2, EN 196-6, EN 196-11: Methods relating to the chemical analysis, fineness, and heat of hydration of cement.
• EN 13925 (parts 1-3): Principles, procedures, and instrumentation for X-ray diffraction analysis of materials.
• ISO 565, ISO 3310-1: Technical requirements and specifications for test sieves, used in sample preparation for microscopy.
• ISO 9277: Reference method for the determination of specific surface area by gas adsorption.

Practical Value

By following prEN 196-17, laboratories and producers gain:

• Reliable, repeatable methods to determine GBS glass content in cement
• Confidence in product conformity to EN 197-1 and other regulatory requirements
• Tools to optimize cement formulations for performance, ensuring the desired reactivity and mechanical properties
• Support for third-party verification and market acceptance through standardized, CEN-recognized procedures

This standard fosters consistency, traceability, and comparative analysis in the European cement industry, promoting quality and reliability in construction materials.

SLOVENSKI STANDARD
01-oktober-2026
Metoda preskušanja cementa - 17. del: Določanje vsebnosti stekla v granulirani
plavžni žlindri kot sestavini za običajni cement
Method of testing cement - Part 17: Determination glass content of granulated blast
furnace slag as constituent for common cement
Prüfverfahren für Zement - Teil 17: Bestimmung des Glasgehalts von Hüttensand als
Bestandteil von Normalzement
Méthode d'essai des ciments - Partie 17: Détermination de la teneur en verre du laitier
granulé de haut-fourneau comme constituant d'un ciment courant
Ta slovenski standard je istoveten z: prEN 196-17
ICS:
91.100.10 Cement. Mavec. Apno. Malta Cement. Gypsum. Lime.
Mortar
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

DRAFT
EUROPEAN STANDARD
NORME EUROPÉENNE
EUROPÄISCHE NORM
August 2026
ICS 91.100.10
English Version
Method of testing cement - Part 17: Determination glass
content of granulated blast furnace slag as constituent for
common cement
Prüfverfahren für Zement - Teil 17: Bestimmung des
Glasgehalts von Hüttensand als Bestandteil von
Normalzement
This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee
CEN/TC 51.
If this draft becomes a European Standard, 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.

This draft European Standard was established by CEN 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.
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.

Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without
notice and shall not be referred to as a European Standard.

EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2026 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 196-17:2026 E
worldwide for CEN national Members.

Contents Page
European foreword . 3
1 Scope . 4
2 Normative references . 4
3 Terms and definitions . 4
4 General requirements for testing . 4
4.1 Number of tests . 4
4.2 Repeatability and reproducibility . 5
4.2.1 Repeatability . 5
4.2.2 Reproducibility . 5
4.3 Expression of masses, volumes, factors and results . 5
5 Principle of test methods (A and B) . 5
6 Procedures. 5
6.1 Preparation of a GBS sample . 5
6.2 Method of determining the moisture content of GBS . 6
6.2.1 Principle . 6
6.2.2 Apparatus . 6
6.2.3 Procedure. 6
6.2.4 Calculation . 6
6.2.5 Report . 6
6.3 Method A, X-ray diffraction . 6
6.3.1 Principle . 6
6.3.2 Apparatus . 7
6.3.3 Sample preparation . 8
6.3.4 Procedure. 8
6.3.5 Data processing . 9
6.3.6 Report .10
6.4 Method B, Polarized optical microscopy .10
6.4.1 Principle .10
6.4.2 Apparatus and materials .11
6.4.3 Sample preparation .11
6.4.4 Procedure.12
6.4.5 Report .13
7 Precision .13
7.1 Method A, X-ray diffraction .13
7.1.1 Repeatability and reproducibility .13
7.2 Method B, Polarized optical microscopy .13
7.2.1 Repeatability and reproducibility .13
Bibliography .14

European foreword
This document (prEN 196-17:2026) has been prepared by Technical Committee CEN/TC 51 “Cement and
building limes”, the secretariat of which is held by NBN.
This document is currently submitted to the CEN Enquiry.
1 Scope
This document describes two equivalent test methods for determining the glass content in Granulated
blast furnace Slag (GBS) as constituent for common cement as defined on EN 197-1.
Method A – Method of determining the glass content of GBS by X-ray diffraction.
Method B – Method of determining the glass content of GBS by polarized optical microscopy.
The glass content (or glassy/amorphous phase) in GBS is the fraction of the material that lacks a
crystalline structure, having solidified rapidly from the melt in the form of amorphous glass.
It is usually expressed as a percentage (wt%) of the total slag.
In the absence of a product standard or a specification in the product standard, the constituent is tested
at the fineness of the intended use.
Furthermore, these test methods are used in manufacturing control of cement constituents for assessing
their conformity to the limit indicated in EN 197-1.
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.
EN 197-1, Cement — Part 1: Common cement — Performance assessment and declaration
EN 196-7, Methods of testing cement — Part 7: Methods of taking and preparing samples of cement
3 Terms and definitions
For the purposes of this document, the terms and definitions given in EN 197-1 and EN 196-7, and the
following 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/
4 General requirements for testing
4.1 Number of tests
For each determination, one or more tests shall be carried out in which the number of measurements to
be taken shall be as specified in the relevant clause of this document (see 6.3 and 6.4).
Where the analysis is one of a series subject to statistical control, the determination of each property by
a single test shall be the minimum required.
Where the analysis is not part of a series subject to statistical control, the number of tests for
determination of each property shall be two.
4.2 Repeatability and reproducibility
4.2.1 Repeatability
Precision under repeatability conditions where independent test results are obtained with the same
method on identical test items (material) in the same laboratory by the same operator using the same
equipment within short intervals of time.
4.2.2 Reproducibility
Precision under reproducibility conditions where test results are obtained with the same method on
identical test items (material) in different laboratories with different operators using different
equipment.
4.3 Expression of masses, volumes, factors and results
Express masses in grams to the nearest 0,001 g.
Express the results, where a single test result has been obtained, to one decimal for method A (6.3) and
for method B (6.4).
Express the results, where two test results have been obtained, as the mean of the results, to one percent.
If the two test results differ by more than twice the standard deviation of repeatability, repeat the test
and take the mean of the two closest test results.
The results of all individual tests shall be recorded.
5 Principle of test methods (A and B)
This document describes two test methods used to the determination of glass content of Granulated
Blast-furnace Slag (GBS).
Method A – Method of determining the glass content of GBS by X-ray diffraction.
Method B – Method of determining the glass content of GBS by polarized optical microscopy.
The results of these test methods can be used to determining the content of glass of GBS.
There is no requirement to preferentially use of Method A and Method B for a given purpose, both
methods are considered equivalent. In many instances the choice is based on the user’s determination of
available equipment.
6 Procedures
6.1 Preparation of a GBS sample
Before the analysis (method A and method B), treat the laboratory sample, taken in accordance with
EN 196-7, as follows to obtain a homogeneous test sample.
If the GBS that has been sampled is a powder, take approximately 100 g of the laboratory sample by
means of a sample divider or by quartering.
If the GBS that has been sampled is not a powder, quartering and size reduction operations are carried
out to obtain representative 100 g in powder with a particle size inferior to 200 µm.
NOTE The size reduction operation can be carried out carefully to avoid any extended fine grinding that can
generate a pollution or a partial amorphisation and then modify the actual glass content.
Before testing the ground GBS, method A (6.3) and method B (6.4), the sample shall be dry at (105 ± 5)
°C for 24 h after the determination of the moisture content of GBS according to 6.2.
Transfer the sample to a clean dry container with an airtight closure and shake vigorously to mix it
thoroughly.
6.2 Method of determining the moisture content of GBS
6.2.1 Principle
The moisture content of the GBS is determined by drying a sample in an oven until constant mass is
achieved.
6.2.2 Apparatus
6.2.2.1 Balance, capable of weighing to an accuracy of ± 0,000 5 g.
6.2.2.2 Shallow glass container, of about 20 g capacity
6.2.2.3 Electric oven, with natural ventilation controlled at (105 ± 5) °C
6.2.2.4 Desiccator, containing a dried desiccant salt like magnesium perchlorate or equivalent
6.2.3 Procedure
Weigh to the nearest 0,001 g, (10 ± 0.050) g of ground GBS into the shallow glass container (6.2.2.2),
which has previously been dried and weighed. Place the container in the electric oven (6.2.2.3) at
(105 ± 5) °C. Heat it for 1 h.
Remove the shallow glass container and allow it to cool in the desiccator (6.2.2.4) to room temperature
and weigh it. Repeat the heating and cooling cycle until constant mass is achieved, i.e. when the difference
between two successive weighings is less than 0,005 g.
6.2.4 Calculation
Calculate the moisture content, C, of the sample as a percentage, to the nearest 0.1 %, from the following
equation:
MM−
( )
C ×100
M
where:
M1 is the mass of initial sample (in g).
M2 is the mass of dried sample (in g).
6.2.5 Report
Report the moisture content as a percentage of the dry mass to the nearest 0,1 %.
6.3 Method A, X-ray diffraction
6.3.1 Principle
X-ray diffraction is a process by which the atoms of a crystalline material interact with radiation in the X-
ray range, generating coherent scattering of the radiation. The diffraction angle depends on the crystal
structure of the material, and the diffraction intensity can be correlated with the amount of material
within the sample.
NOTE Cf. EN 13925-1 and EN 13925-2 for more details.
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prEN 196-
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