oSIST prEN 196-5:2026

• Abstract:

  In this document, the pozzolanicity of a cement is assessed by comparing the concentration of calcium ion, expressed as calcium oxide, present in the aqueous solution in contact with the hydrated cement, after a fixed period of time, with the quantity of calcium ion capable of saturating a solution of the same alkalinity.

• Status: Not Published
• Public Enquiry End Date: 19-Nov-2026
• ICS: 91.100.10 - Cement. Gypsum. Lime. Mortar
• Technical Committee: CAA - Mineral binders and masonry
• Current Stage: 4020 - Public enquire (PE) (Adopted Project)
• Start Date: 05-Oct-2026
• Due Date: 22-Feb-2027
• Directive: 305/2011 - Regulation (eu) No 305/2011 of the European Parliament and of the Council of 9 march 2011 laying down harmonised conditions for the marketing of construction products and repealing council directive 89/106/eec
• Ref Project: prEN 196-5 - Methods of testing cement - Part 5: Pozzolanicity test for pozzolanic cement

• Revises: SIST EN 196-5:2011 - Methods of testing cement - Part 5: Pozzolanicity test for pozzolanic cement
• Effective Date: 24-Jun-2026

oSIST prEN 196-5:2026 is the Slovenian publication of the CEN draft European Standard prEN 196-5, issued by SIST. It specifies the reference method for measuring the pozzolanicity of pozzolanic cements by comparing the calcium ion concentration in solution, expressed as calcium oxide, with the saturation concentration at the same alkalinity. The method is used in cement laboratories that test pozzolanic cements according to EN 197-1.

What does oSIST prEN 196-5:2026 specify?

oSIST prEN 196-5:2026 specifies a laboratory test for pozzolanicity and says where it applies and where it does not. It is presented as the reference procedure, so it is the method to use when a formal assessment is needed.

The document applies to pozzolanic cements according to EN 197-1. It does not apply to Portland pozzolana cements or to pozzolanas.

The document is organized into clauses covering scope, normative references, principle, general testing requirements, sample preparation, reagents, apparatus, solution standardization, procedure, results, reporting, and a bibliography. In practice, that structure takes the reader from sampling through measurement to the final pass/fail statement.

What are the key requirements of oSIST prEN 196-5:2026?

The core requirement in oSIST prEN 196-5:2026 is to compare the calcium ion level in the filtered solution, expressed as calcium oxide, with the saturation level for the same alkalinity. A cement passes when the measured calcium level is below the saturation curve. That matters because the result is not a general chemical analysis - it is a direct yes/no assessment of pozzolanicity.

Sample preparation and test conditions

Clause 6 requires a homogeneous test sample prepared from the laboratory sample taken according to EN 196-7. The sample is sieved, retained material is ground to pass the sieve, and the material is mixed quickly in an airtight container. In practice, this limits moisture exchange and carbonation, both of which can distort the result.

Clause 10 sets the test conditions: 20.00 g of cement is mixed with 100 ml of freshly decarbonized water in a sealed polyethylene container and stored at 40 °C. The solution is filtered after 8 d or 15 d. If the cement already passes at 8 d, the test does not need to continue to 15 d.

Reagents, apparatus and standardization

Clauses 7 to 9 require analytical-quality reagents, specific indicators, a standardized EDTA solution, and a standardized 0.1 mol/l hydrochloric acid solution. The pH is adjusted to 12.5 before the calcium titration. This standardization step matters because the final calcium and alkalinity values depend on titrant strength, not just on the sample.

Clause 9 allows photometric or visual end-point determination for the EDTA titration. The draft introduces Calconcarbonic acid indicator as a visual option. That gives laboratories a practical alternative when photometric equipment is not used.

Calculation, precision and reporting

Clause 11 requires the hydroxyl ion concentration and calcium ion concentration to be calculated and reported to the nearest 0.1 mmol/l. If two results differ too much, the test is repeated and the two closest results are used. Clause 11 also gives repeatability and reproducibility data, which helps users judge whether their results are consistent between runs and between laboratories.

Clause 12 requires the report to state whether the cement satisfies or does not satisfy the test for pozzolanicity according to EN 196-5. That is the form most users need for quality control, conformity work, or supplier documentation.

What changed in oSIST prEN 196-5:2026 from the previous edition?

oSIST prEN 196-5:2026 supersedes EN 196-5:2011. The foreword states these technical changes:

• redefinition of the introduction
• introduction of the Calconcarbonic acid indicator
• modification of the EDTA standardization paragraph, including a visual end-point option
• modification of the storage and filtration paragraph
• modification of the calcium result repeatability data

Which standards are used with oSIST prEN 196-5:2026?

• EN 196-7 - gives the sampling and sample preparation method for the laboratory sample.
• EN ISO 385 - specifies the burettes used in the titration work.
• EN ISO 835 - specifies the graduated pipettes used in the procedure.
• EN 197-1 - identifies the pozzolanic cements to which this method applies.

What does the oSIST prEN 196-5:2026 document contain?

The document contains the full testing workflow: sample preparation, reagent preparation, apparatus lists, solution standardization, the storage and filtration step, alkalinity titration, calcium titration, and the final pass/fail assessment. It also includes Figure 1, which is the decision diagram for assessing pozzolanicity, and the calculation steps needed to convert titration volumes into hydroxyl ion and calcium ion concentrations.

It is written for laboratory use, so it is practical rather than theoretical. The main tasks it supports are routine testing, conformity checking, and dispute testing for pozzolanic cements.

SLOVENSKI STANDARD
01-november-2026
Metode preskušanja cementa - 5. del: Preskus pucolanske aktivnosti za
pucolanske cemente
Methods of testing cement - Part 5: Pozzolanicity test for pozzolanic cement
Prüfverfahren für Zement - Teil 5: Prüfung der Puzzolanität von Puzzolanzementen
Méthodes d'essais des ciments - Partie 5: Essai de pouzzolanicité des ciments
pouzzolaniques
Ta slovenski standard je istoveten z: prEN 196-5
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
September 2026
ICS 91.100.10 Will supersede EN 196-5:2011
English Version
Methods of testing cement - Part 5: Pozzolanicity test for
pozzolanic cement
Méthodes d'essais des ciments - Partie 5: Essai de Prüfverfahren für Zement - Teil 5: Prüfung der
pouzzolanicité des ciments pouzzolaniques Puzzolanität von Puzzolanzementen
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 196-5:2026 E
worldwide for CEN national Members.

Contents Page
European foreword . 3
Introduction . 4
1 Scope . 5
2 Normative references . 5
3 Terms and definitions . 5
4 Principle . 5
5 General requirements for testing . 5
5.1 Number of tests . 5
5.2 Repeatability and reproducibility. 6
5.3 Expression of masses, volumes and factors . 6
5.4 Determination of constant mass . 6
6 Preparation of a test sample of cement . 6
7 Reagents . 6
7.1 General . 6
8 Apparatus . 7
9 Standardization of solutions . 8
9.1 Standardization of the EDTA solution . 8
9.2 Standardization of the 0,1 mol/l solution of hydrochloric acid . 9
10 Procedure . 9
10.1 Storage and filtration . 9
10.2 Determination of the hydroxyl ion concentration . 10
10.3 Determination of the calcium oxide concentration . 10
11 Results . 11
11.1 Calculation and expression of results . 11
11.2 Assessment of pozzolanicity . 11
11.3 Repeatability and reproducibility. 12
12 Reporting of results . 12
Bibliography . 13

European foreword
This document (prEN 196-5:2026) 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.
This document will supersede EN 196-5:2011.
EN 196-5:2011:
— redefinition of the introduction
— introduction of indicator: Calconcarbonic acid indicator
— modification of paragraph 8.1: Standardization of the EDTA solution b) Visual determination
of the end point
— modification of paragraph 9.1: Storage and filtration
— modification of paragraph 10.3: data of repeatability.
Introduction
In this document, the pozzolanicity of a cement is assessed by comparing the concentration of
calcium ion, expressed as calcium oxide, present in the aqueous solution in contact with the
hydrated cement, after a fixed period of time, with the quantity of calcium ion capable of
saturating a solution of the same alkalinity.
1 Scope
This document specifies the method of measuring the pozzolanicity of pozzolanic cements
according to EN 197-1. This document does not apply to Portland pozzolana cements or to
pozzolanas.
This method constitutes the reference procedure.
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.
EN 196-7, Methods of testing cement — Methods for sampling and sample preparation of common
cement and its constituents
EN ISO 385, Laboratory glassware — Burettes
EN ISO 835, Laboratory glassware — Graduated pipettes
3 Terms and definitions
No terms and definitions are listed in this document.
4 Principle
The pozzolanicity is assessed by comparing the concentration of calcium ion, expressed as
calcium oxide, present in the aqueous solution in contact with the hydrated cement, after a fixed
period of time, with the quantity of calcium ion capable of saturating a solution of the same
alkalinity. The cement is considered to satisfy the test, i.e. gives a positive result, if the
concentration of calcium ion in the solution is lower than the saturation concentration.
NOTE Experiment has shown that a mixture of 20 g of cement and 100 ml of water at 40 °C achieves
equilibrium after a period of between 8 d and 15 d. If the cement satisfies the test at 8 d (see 11.2) it is not
necessary to continue to 15 d.
5 General requirements for testing
5.1 Number of tests
Where the determination is one of a series subject to statistical control, determination by a single
test shall be the minimum required.
Where the determination is not part of a series subject to statistical control, the number of tests
shall be two (see also 11.1)
In the case of dispute, the number of tests shall be two.
5.2 Repeatability and reproducibility
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.
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.
Repeatability and reproducibility in this document are expressed as repeatability standard
deviation(s) and reproducibility standard deviation(s).
5.3 Expression of masses, volumes and factors
Express masses in grams to the nearest 0,000 1 g and volumes from the burette in millilitres to
the nearest 0,05 ml. Express the factors of solutions, given by the mean of three determinations,
to three decimal places.
5.4 Determination of constant mass
Determine constant mass by drying for successive periods at the stated temperature, or making
successive 15 min ignitions, followed each time by cooling and then weighing. Constant mass is
reached when the difference between two successive weightings is less than 0,000 5 g.
6 Preparation of a test sample of cement
Before starting the determinations, treat the laboratory sample, taken in accordance with
EN 196-7, as follows to obtain a homogenous test sample.
Take approximately 100 g of the sample using a sample divider or by quartering. Sieve this
portion on a 150 µm or 125 µm sieve until the residue remains constant. Grind the retained
material so that it completely passes the 150 µm or 125 µm sieve. Transfer the sample to a clean
dry container with an airtight closure and shake vigorously to mix it thoroughly
Carry out all operations as quickly as possible to ensure that the sample is exposed to ambient air
only for the minimum time
7 Reagents
7.1 General
Use only reagents of analytical quality. References to water mean distilled or de-ionized water
having an electrical conductivity ≤ 0,5 mS/m. The quantities of reagents listed are to indicate
concentrations; actual quantities to be prepared shall be adjusted according to the amounts
required. Attention to tolerances when weighing.
Unless otherwise stated (%) means percent by mass.
3 3
7.1.1 Concentrated hydrochloric acid (HCl), (ρ = 1,18 g/cm to 1,19 g/cm ).
7.1.2 Dilute hydrochloric acid, about 0,1 mol/l, prepared by adding 8,5 ml of concentrated
hydrochloric acid (7.1.1), measured using the 50 ml burette (8.8), to a 1 l volumetric flask (8.10)
containing about 500 ml
...