prEN 196-5

• 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
• Publication Date: 21-Aug-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: 03-Sep-2026
• Due Date: 11-May-2027
• Completion Date: 03-Sep-2026
• 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: oSIST prEN 196-5:2026 - Methods of testing cement - Part 5: Pozzolanicity test for pozzolanic cement

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

prEN 196-5 is a CEN draft European Standard for testing the pozzolanicity of pozzolanic cement. It specifies a reference laboratory method that compares calcium ion, expressed as calcium oxide, in solution with the calcium concentration needed to saturate a solution of the same alkalinity.

The document is for laboratories, manufacturers, and quality teams that need a common pass/fail test for pozzolanic cement according to EN 197-1.

What does prEN 196-5 specify?

prEN 196-5 specifies the method for measuring the pozzolanicity of pozzolanic cements according to EN 197-1. It is the reference procedure for this test and it does not apply to Portland pozzolana cements or to pozzolanas.

The document is organized into clauses 1 to 12, covering scope, references, terms, principle, test rules, sample preparation, reagents, apparatus, solution standardization, procedure, results, and reporting.

What are the key requirements of prEN 196-5?

Test basis and acceptance

Clause 4 states that pozzolanicity is judged by comparing the calcium ion concentration in the aqueous phase after a fixed time with the saturation concentration at the same alkalinity. A cement passes when the measured calcium concentration is below the saturation curve, so the result is a laboratory comparison rather than a direct strength or composition test.

Clause 4 also notes that a 20 g cement and 100 ml water mixture at 40 °C typically reaches equilibrium between 8 d and 15 d. If the cement already passes at 8 d, the test does not need to continue to 15 d.

Sampling, test count, and precision handling

Clause 5 sets the minimum number of tests. One test is enough when the determination is part of a statistically controlled series, but two tests are required otherwise and also in case of dispute. This matters because it sets when a single result is acceptable and when averaging is required.

Clause 5 also defines repeatability and reproducibility for this document, and it gives the reporting precision for masses, volumes, and solution factors. Clause 11 later uses repeatability to decide when two results are too far apart and the test must be repeated.

Sample preparation, reagents, and apparatus

Clause 6 requires a homogeneous cement test sample prepared from the laboratory sample taken according to EN 196-7. The sample is sieved, any retained material is ground to pass the sieve, and the prepared sample is stored airtight and handled quickly to limit exposure to ambient air.

Clauses 7 and 8 set the reagent quality and apparatus needed for the method. The procedure uses analytical-grade reagents, low-conductivity water, a thermostatically controlled enclosure at 40 ± 1 °C, a pH meter, a balance, burettes, pipettes, and an absorbance measuring setup at 520 nm or 620 nm for one of the end-point options.

Solution standardization and measurement steps

Clause 9 standardizes the EDTA (ethylenediaminetetra-acetic acid) solution using calcium carbonate, and standardizes the 0.1 mol/l hydrochloric acid solution using sodium carbonate. The EDTA end point may be found photometrically or visually, and this affects how the titration is read in practice.

Clause 10 describes the core test: the cement is stored with freshly decarbonized water in a sealed polyethylene container, kept at 40 °C, then filtered after 8 d or 15 d. The filtrate is titrated first for hydroxyl ion concentration and then for calcium oxide concentration, so the laboratory gets the two values needed for the final assessment.

Result calculation and reporting

Clause 11 requires results to be calculated and expressed to the nearest 0.1 mmol/l. The measured point is plotted against the saturation curve in Figure 1, and the cement passes when the point lies below that curve.

Clause 12 requires all individual results to be recorded and the final report to state whether the cement satisfies or does not satisfy the test for pozzolanicity according to EN 196-5.

What terms does prEN 196-5 use?

• Pozzolanicity - the property assessed by comparing dissolved calcium in the test solution with the calcium level needed for saturation at the same alkalinity.
• Pozzolanic cement - the cement product category covered by the method, as identified in EN 197-1.
• Hydroxyl ion - the alkalinity value measured in the filtrate and used together with calcium oxide in the final plot.
• Calcium ion expressed as calcium oxide - the calcium result format used throughout the method for comparison and reporting.
• Repeatability - agreement of results obtained under the same laboratory conditions with the same method, operator, equipment, and short time interval.
• Reproducibility - agreement of results obtained in different laboratories with different operators and equipment.
• EDTA - the titrant used to determine calcium in the filtrate after the solution has been adjusted to the required pH.

Who uses prEN 196-5?

prEN 196-5 is used by cement testing laboratories, cement producers, and quality control staff who need to verify pozzolanicity against a common reference method. It is also relevant to conformity assessment and dispute testing, because the standard sets the test count, precision handling, and reporting format.

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

prEN 196-5:2026 will supersede EN 196-5:2011. The significant technical changes stated for this draft are:

• redefinition of the introduction
• introduction of the Calconcarbonic acid indicator
• modification of the EDTA standardization section to include visual determination of the end point
• modification of the storage and filtration section
• modification of the repeatability data in the calcium determination section

Which standards are used with prEN 196-5?

Standard	What it contributes
EN 196-7	Sampling and sample preparation of common cement and its constituents
EN ISO 385	Requirements for burettes used in the titrations
EN ISO 835	Requirements for graduated pipettes used in the procedure
EN 197-1	The cement classification used to identify the pozzolanic cements covered by this method

What does the prEN 196-5 document contain?

The document contains the test principle, laboratory preparation steps, reagent recipes, apparatus requirements, and two solution-standardization procedures. It also includes the storage, filtration, titration, calculation, and pass/fail assessment steps needed to carry out the test.

It provides a saturation curve in Figure 1 for judging the result, plus formulas for solution factors and for calculating hydroxyl ion and calcium oxide concentrations. The reporting clause tells the user what to record and how to state the final conclusion.

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
...