CEN/TC 104

Date: 2026-02-19

prEN 18314:2026

Secretariat: SN

Natural pozzolana and natural activated pozzolanic material — Definitions, specifications, and conformity criteria

Einführendes Element — Haupt-Element — Ergänzendes Element

Élément introductif — Élément central — Élément complémentaire

CCMC will prepare and attach the official title page.

Contents Page

European foreword 3

Introduction 4

1 Scope 5

2 Normative references 5

3 Terms and definitions 5

4 Specifications 8

4.1 General 8

4.2 Chemical requirements 8

4.2.1 Chemical composition 8

4.2.2 Clay content 8

4.2.3 Chloride 8

4.2.4 Sulphate 8

4.2.5 Alkali 8

4.2.6 Total organic carbon 8

4.2.7 Additives 8

4.3 Physical requirements 9

4.3.1 Fineness 9

4.3.2 Soundness 9

4.3.3 Particle density 9

4.3.4 Moisture 9

4.3.5 Water requirement 9

4.3.6 Reactivity 9

4.3.7 Requirements when combined with the test cement 9

4.4 Other requirements 10

4.4.1 Durability requirements 10

4.4.2 Release of dangerous substances and emission of radioactivity 10

4.4.3 Information to be supplied upon request 10

5 Standard designation 10

6 Packaging and labelling 11

7 Sampling 11

8 Conformity criteria 11

8.1 General requirements 11

8.2 Statistical conformity criteria 12

8.2.1 General 12

8.2.2 Inspection by variables 13

8.2.3 Inspection by attributes 14

8.3 Single result conformity criteria 14

Annex A (informative) Assessment and Verification of Conformity 16

Annex B (informative) Attestation of conformity 24

Annex C (informative) Evaluation of the representativeness and the accuracy of the 28-day activity index test results 25

Bibliography 27

European foreword

This document (prEN 18314:2026) has been prepared by Technical Committee CEN/TC 104 “Concrete and related products”, the secretariat of which is held by SN.

This document is currently submitted to the CEN Enquiry.

Introduction

Natural pozzolana and natural activated pozzolanic materials are typically siliceous or silico-aluminous materials with pozzolanic properties; examples include materials of volcanic origin, diatomite earths, calcined clays or shales. The use of natural pozzolanic materials in concrete production in some European countries, based on national experience and tradition is a current trend.

If natural pozzolanic materials are out of the scope of this document, their suitability for use as additions in concrete according to EN 206:2013+A2:2021 can also be established from national standards or provisions or European Technical Approvals (ETA) valid in the place of use of the concrete and which refer specifically to the use of the addition in concrete conforming to EN 206:2013+A2:2021.

When using natural pozzolanic materials conforming to this document, it can be noted that, apart from the pozzolanic effect of the product, certain properties of fresh and hardened concrete can be affected. Where relevant, such effects need to be considered in concrete mix design.

This document specifies requirements for chemical and physical properties of natural pozzolana and natural activated pozzolanic material for use as addition to concrete, and for use in mortar and grouts.

It also specifies requirements for conformity criteria.

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 196‑1, Methods of testing cement — Part 1: Determination of strength

EN 196‑2, Methods of testing cement — Part 2: Chemical analysis of cement

EN 196‑3, Methods of testing cement — Part 3: Determination of setting times and soundness

EN 196‑6, Methods of testing cement — Part 6: Determination of fineness

EN 196‑7, Methods of testing cement — Part 7: Methods of taking and preparing samples of cement

EN 196‑12, Methods of testing cement — Part 12: Reactivity of cement constituents - Heat of hydration and bound water content methods

EN 197‑1, Cement — Part 1: Composition, specifications and conformity criteria for common cements

EN 451‑2, Method of testing fly ash — Part 2: Determination of fineness by wet sieving

EN 933‑9, Tests for geometrical properties of aggregates — Part 9: Assessment of fines - Methylene blue test

EN 933‑10, Tests for geometrical properties of aggregates — Part 10: Assessment of fines - Grading of filler aggregates (air jet sieving)

EN 1097‑5, Tests for mechanical and physical properties of aggregates — Part 5: Determination of the water content by drying in a ventilated oven

EN 13639, Determination of total organic carbon in limestone

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

pozzolanic properties

propensity of a material to react with calcium hydroxide (Ca(OH)₂) and water at ambient temperature to form calcium silicate and calcium aluminate hydrates with cementitious properties that enable to obtain or enhance specific concrete properties

3.2

addition

finely divided inorganic constituent used in concrete in order to improve certain properties or to achieve special properties

[SOURCE: FprEN 206‑1:2025, definition 3.2.1]

3.3

natural pozzolana

material of natural origin mainly comprised of silicate and aluminosilicate compounds that, when finely ground, presents pozzolanic properties (3.1)

Note 1 to entry: The term “natural pozzolana” is used to differentiate from industrial pozzolana such as fly ash or silica fume whose properties and performance requirements are set by other standards.

3.4

natural activated pozzolanic material

natural pozzolanic material activated by a specific treatment (thermal, chemical and/or mechanical) intended to obtain pozzolanic properties (3.1) of the material

Note 1 to entry: Chemical activation does not include alkali activated binders like geopolymers.

3.5

autocontrol

continuous statistical quality control of the natural pozzolana and natural activated pozzolanic material based on the testing of samples taken by the producer or their agent at point(s) of release from the producing facility

3.6

control period

period of production and/or dispatch identified for the evaluation of the autocontrol test results

3.7

characteristic value

value of the required property outside of which lies a specified percentage, the percentile Pk, of all the values of the population

3.8

single result limit value

limit value of a chemical or physical property which – for any single test result – in the case of an upper limit is not to be exceeded or in the case of a lower limit is, as a minimum, to be reached

3.9

allowable probability of acceptance Consumer’s Risk (CR)

for a given sampling plan, the allowed probability of acceptance of natural pozzolana and natural activated pozzolanic material with a characteristic value outside the specified minimum or maximum values

3.10

sampling plan

specific plan which states the (statistical) sample size(s) to be used, the percentile P_k, and the allowable probability of acceptance CR

3.11

spot sample

sample taken at the same time and from one and the same place, relating to the intended tests which can be obtained by combining one or more immediately consecutive increments

3.12

certificate of conformity of the factory production control

document issued under the rules of the scheme for the Assessment and Verification of Conformity indicating that adequate confidence is provided that factory production control is in conformity with the relevant product specification standard

3.13

factory

facility used by a manufacturer for the production of a natural pozzolana and natural activated pozzolanic material using equipment which is suitable for continuous mass production of a natural pozzolana and natural activated pozzolanic material

Note 1 to entry: In particular, equipment for adequate grinding and/or selection and the necessary silo capacity for the storage and dispatch of each natural pozzolana and natural activated pozzolanic material produced.

Note 2 to entry: This equipment and the production control applied allow the control of production with sufficient accuracy to ensure that the requirements of this document are met.

3.14

new factory

factory for which the conformity of the factory production control has not been certified using this document

3.15

existing factory

factory for which the conformity of the factory production control has already been certified using this document

3.16

factory production control

documented, permanent and internal control of production in a factory

3.17

initial period

immediate period starting after the first issuing of the certificate of conformity of the factory production control for natural pozzolana and natural activated pozzolanic material and at the latest from the first dispatching of natural pozzolana and natural activated pozzolanic material

3.18

certification body

third-party conformity assessment body operating certification schemes

3.19

works’ quality documentation

documentation that provides information on the factory production control which is applied by a manufacturer at a particular factory to ensure constancy of performance of the natural pozzolana and natural activated pozzolanic material

Natural pozzolana and natural activated pozzolanic material may be processed by any combination of selection, blending, homogenization, drying, and grinding depending on their state of production or deliveries.

Natural pozzolana and natural activated pozzolanic material may be supplied nominally dry or as a suspension in water.

The content of silicon dioxide (SiO₂), calcium oxide (CaO), magnesium oxide (MgO), aluminium oxide (Al₂O₃) and iron oxide (Fe₂O₃), shall be determined in accordance with EN 196‑2. The contents expressed in % by mass shall be declared, where specified.

The clay content shall be determined by the methylene blue test in accordance with EN 933‑9. The contents expressed in g/kg shall be declared, where specified.

The chloride (Cl^—) content shall be determined in accordance with EN 196‑2 and should not exceed 0,10 % by mass. Values exceeding 0,10 % by mass shall be declared.

The sulphate (SO₃) content shall be determined in accordance with EN 196‑2 and should not exceed 3,0 % by mass. Values exceeding 3,0 % by mass shall be declared.

The total content of alkalis (Na₂Oeq) shall be determined in accordance with EN 196‑2. Maximum values shall be declared.

The total organic carbon content shall be determined in accordance with EN 13639.

The total organic carbon content expressed by mass of pozzolana shall be declared.

NOTE The determination of total organic content, together with other parameters like moisture content, gives a much better characterization of constituents influencing the material’s performance. The loss on ignition of natural pozzolana and natural activated pozzolanic materials summarizes the mass loss from different kind of constituents which are ignited during the test. However, it is not possible to make a distinction between those constituents and the assessment in which way they can affect the performance of the material.

The total quantity of additives such as grinding agents and rheology agents shall not exceed 1,0 % by mass of pozzolana.

These additives shall not promote corrosion of the reinforcement or impair the properties of the concrete or mortar made from the natural pozzolana or natural activated pozzolanic material.

The fineness of pozzolana shall be expressed as the mass proportion in percent of pozzolana retained when sieved on a 200 µm mesh sieve and on a 45 μm mesh sieve. The residue on the 200 µm sieve shall not exceed 5 % by mass.

The fineness shall be determined by wet sieving in accordance with EN 451‑2, or by air jet sieving in accordance with EN 933‑10 and the results shall be declared.

Other sieves may be provided on request such as 63 µm mesh sieve instead of a 45 µm mesh sieve.

The soundness shall be determined on 25 % natural pozzolana plus 75 % test cement (both by mass) in accordance with EN 196‑3 and shall not be greater than 10 mm.

The particle density shall be determined in accordance with EN 196‑6, and it shall be declared.

Where the natural pozzolana or natural activated pozzolanic material is supplied nominally dry the moisture content shall be determined in accordance with EN 1097‑5 and declared in percentage by mass.

Where the natural pozzolana or natural activated pozzolanic material is supplied in a suspension, the dry mass content of the suspension shall not deviate from the value declared by more than ± 2 % by mass of the material when determined by drying a representative sample of at least 5 g of suspension in a well-ventilated oven at (105 ± 5) °C to constant mass. Constant mass is achieved when the difference between successive weight determinations during drying at (105 ± 5) °C, not less than least 1 h apart, is less than 0,2 %.

The water requirement shall be determined on 25 % pozzolana plus 75 % test cement (both by mass) in accordance with EN 196‑3. The determined value shall be declared.

Either heat of hydration or bound water content shall be determined in accordance with EN 196‑12 and shall be measured at 7 days.

Either heat of hydration or bound water content shall be used and declared to assess the reactivity.

The heat of hydration shall be at least 90 J/g of pozzolana.

The bound water content shall be at least 3.5 % by mass of dry paste.

Test cement

The test cement shall conform to EN 197‑1 and be CEM I with strength class 42,5 or higher. It shall also be characterized by its fineness, tricalcium aluminate, and alkali contents as follows:

— fineness (Blaine): 300 m²/kg - 460 m²/kg;

— tricalcium aluminate: 6 %–12 % by mass;

— alkalis (Na₂O_eq): 0,5 – 1,2 % by mass.

Initial setting time

The initial setting time shall be determined on 25 % natural pozzolana plus 75 % test cement (both by mass) in accordance with EN 196‑3 and shall not be more than twice as long as that of the test cement specified in Clause 4.3.7.1, on its own.

Activity index

The activity index shall be expressed as the ratio (in percent) of the compressive strength of the combination (by mass) of 25 % of pozzolana with 75 % of test cement, to the compressive strength of the test cement on its own. The compressive strengths shall be determined in accordance with EN 196‑1 and the water: combination ratio and the water: cement ratio shall both be 0,50.

Preparation of standard mortar bars and determination of the compressive strength shall be carried out in accordance with EN 196‑1.

The activity index at 28 days and 90 days shall not be less than 75 % and 85 % of the strength of the test cement, respectively. In the case, the activity index at 28 days exceeds 90 %, the testing at 90 days is not necessary.

The mortar containing pozzolana may be mixed with an amount of superplasticizer (as seen in EN 934‑2) so that the mortar has a consistency equivalent to the reference mortar when tested by the flow table method, as seen in EN 413‑2. The type of superplasticizer and its amount by mass of cement shall be declared.

Natural pozzolana and natural activated pozzolanic material conforming to this document is deemed to satisfy the durability requirements for concrete.

NOTE Requirements for concrete durability can be found in the concrete standard series EN 206 and national regulations.

Additional information for the release of dangerous substances and emission of radioactivity may be supplied upon request where specified.

NOTE Requirements can be found in transposed European legislation and national laws, regulations and administrative provisions.

Additional information may be supplied upon request where specified.

Natural pozzolana and natural activated pozzolanic material shall be designated according to the type of material:

EXAMPLE 1 Natural pozzolana is designated by

Natural pozzolana EN XXXXX

EXAMPLE 2 Natural activated pozzolanic material is designated by

Natural activated pozzolanic material EN XXXX

Natural pozzolana and natural activated pozzolanic material may be delivered in suitable packages or by means of suitable bulk-delivery transportation systems. The following information shall be marked on the packages or in the case of bulk delivery, on the documents:

— number of this document;

— standard designation of the product;

— name or identification mark of the factory where the natural pozzolana and natural activated pozzolanic material was manufactured;

— where appropriate, additional identification to distinguish between different natural pozzolana and natural activated pozzolanic material produced in the same factory;

— if declared, the characteristics given in 4.2.1 and 4.2.2.

Spot samples, equally distributed over the manufacturing period, shall be taken at the point of release into packages or a system for bulk-delivery transportation or, alternatively, directly from bulk-delivery transportation systems or packages, using the equipment and principles described in EN 196‑7.

For the purpose of carrying out all the analyses and tests needed to show conformity or non-conformity to the requirements set out in Clause 4, a representative laboratory sample of natural pozzolana or natural activated pozzolanic material of at least 1 kg is required. This sample shall be obtained by subdividing, such as quartering, a spot sample of at least 5 kg.

The conformity of natural pozzolana and natural activated pozzolanic material covered by this document shall be demonstrated by:

— Factory production control;

— Assessment of the performance of the natural pozzolana and natural activated pozzolanic material;

— Autocontrol testing of samples;

— Audit testing of samples taken at the factory;

— Initial inspection of the manufacturing plant and of factory production control;

— Continuing surveillance, assessment and evaluation of factory production.

NOTE Additional information about assessment and conformity are given in Annex A, Annex B and Annex C.

Conformity of natural pozzolana and natural activated pozzolanic material to this document shall be continually evaluated on the basis of testing of spot samples.

The properties, test methods and the minimum testing frequencies for the autocontrol testing are specified in Table 1.

Table 1 — Properties, test methods and minimum testing frequencies for the autocontrol testing by the manufacturer or their agent and the statistical assessment procedure

Conformity shall be formulated in terms of a statistical criterion based on:

a) the required characteristic values for chemical and physical properties as specified in Clause 4;

b) a percentile P_k of 10 % on which the required characteristic value is based;

c) an allowable probability of acceptance CR of 5 %.

Conformity to the requirements in this document shall be verified either by variables or by attributes, as described in 8.2.2 and 8.2.3 and as specified in Table 1.

A minimum of ten samples shall be used for assessing the conformity and shall represent a period of not more than twelve months and not less than one month.

For this inspection, the test results are assumed to be normally distributed. Conformity is verified when Formulae (1) or (2), as relevant, are satisfied:

(1)

or

(2)

where

is the arithmetic mean of the totality of the autocontrol test results in the control period;

s is the standard deviation of the totality of the autocontrol test results in the control period;

k_A is the acceptability constant;

L is the specified lower limit given in Clause 4;

U is the specified upper limit given in Clause 4.

The acceptability constant k_A depends on the percentile P_k on which the characteristic value is based, on the allowable probability of acceptance CR and on the number n of the test results. Values of k_A are listed in Table 2.

Table 2 — Acceptability constant k_A (P_k = 10 %) at CR = 5 %

The number c_D of test results below or above the characteristic value shall be counted and compared with an acceptable number c_A, calculated from the number n of autocontrol test results and the percentile P_k as specified in Table 3.

Conformity is verified if Formula (3) is satisfied:

(3)

The value of c_A depends on the percentile P_k on which the characteristic value is based, on the allowable probability of acceptance CR and on a number n of the test results. Values of c_A are listed in Table 3.

Table 3 — Values of c_A (P_k = 10 %) at CR = 5 %

In addition to the statistical conformity criteria, conformity of test results to the requirements of this document requires that it shall be verified that each test result remains within the single result limit values specified in Table 4.

Table 4 — Limit values for single results

1. 
   (informative)
   
   Assessment and Verification of Conformity
   1. General

This annex sets outs details of a scheme for conformity assessment and verification of natural pozzolana and natural activated pozzolanic materials. This scheme is similar to those adopted for other cementitious materials. The annex provides technical rules for the factory production control, further testing of samples taken at the manufacturing plant (autocontrol testing) and the assessment of the performance of the natural pozzolana and natural activated pozzolanic material, initial inspection of the manufacturing plant and of the factory production control and audit testing of samples. It also provides rules for actions to be followed in the event of non-conformity.

• 1. Factory production control
     1. General requirements
        1. Concept

Factory production control means the permanent internal control of natural pozzolana and natural activated pozzolanic material production and consists of internal quality control (see A.2.2) completed by autocontrol testing of samples of natural pozzolana and natural activated pozzolanic material taken at the point of release (see A.4).

NOTE 1 The requirements of this Annex as regards factory production control apply to factories.

NOTE 2 The requirements of this Annex regarding factory production control take into account the clauses of EN ISO 9001 which are relevant to the production, process control and testing of natural pozzolana and natural activated pozzolanic material.

• • • 1. Works’ quality documentation

The manufacturer's documentation and procedures for factory production control shall be described in a Works' quality documentation, which shall adequately describe, among other things for each factory:

a) the quality aims and the organisational structure, responsibilities and powers of the management with regard to product quality and the means to monitor the achievement of the required product quality and the effective operation of the internal quality control (see A.2.1.3 and A.2.2);

b) the manufacturing and quality control techniques, processes and systematic actions that will be used (see A.2.2.1);

c) the inspections and tests that will be carried out before, during and after manufacture, and the frequency with which they will be carried out (see A.2.2.2).

The Works’ quality documentation shall include an adequate system of documentation (see A.2.1.4)

The Works' quality documentation shall address and document the procedures operated to ensure that the manufactured natural pozzolana and natural activated pozzolanic material conforms to the performance(s) declared in accordance with this document. The documentation may reference associated documents which provide further details of the autocontrol testing of samples and the internal quality control. For the purpose of this scheme, the term Works' quality documentation shall be considered to include these associated documents.

In the case of an existing quality management system according to EN ISO 9001, the corresponding quality documentation may also be applied for certification of conformity of the factory production control if it meets all requirements of this annex which are relevant to the factory production control of natural pozzolana and natural activated pozzolanic material.

• • • 1. Quality management system
         1. Quality policy statement

The Works’ quality documentation shall include a statement by management defining its quality policy, objectives and commitments to the attainment of product quality.

• • • • 1. Quality manager

A quality manager shall be appointed who, irrespective of other responsibilities, shall have defined and adequate authority and responsibility for ensuring that the requirements of this annex for the Assessment and Verification of Conformity are implemented and maintained.

• • • • 1. Internal audits and management review

In order to ensure the continuing suitability and effectiveness of the Works’ quality documentation to meet the requirements of this annex:

a) internal audits covering the scope of A.2;

b) a management review of the functioning and the results of the factory production control, taking into account records of the internal audits shall be performed at least once a year.

• • • • 1. Training

The Works' quality documentation shall describe the measures taken to ensure that all the personnel involved in operations that can affect internal quality control and product quality have appropriate experience or training. Appropriate records shall be retained.

• • • 1. System of documentation
         1. Document control

All documents and data related to factory production control and to this scheme for the Assessment and Verification of Conformity shall be controlled.

This control shall ensure that the appropriate issues of all documents are available at essential locations, that obsolete documents are withdrawn and that changes or modifications to any document are effectively introduced.

A system shall be established to identify the current version of documents in order to prevent the use of non-applicable documents.

• • • • 1. Quality records

Records shall be retained to provide evidence of factory production control for at least the period required.

• • 1. Internal quality control
       1. Process control
          1. General

The Works' quality documentation shall describe the parameters for process planning, process control and testing, inspection, corrective action, verification, dispatch and the associated records for each factory.

• • • • 1. Control of off-specification production or non-conformity

The Works' quality documentation shall contain procedures for the review and adjustment of the factory production control in case of off-specification production or non-conformity.

The actions taken in the event of non-conformity shall be recorded in a report subject to inspection during the management review.

• • • 1. Measuring and testing
         1. Inspection, measuring and test equipment

The equipment for in-process inspection and testing shall be regularly checked and calibrated in accordance with the procedures and frequencies laid down in the Works' quality documentation.

• • • • 1. Inspection and test status

Procedures for the inspection and test status through the stages of manufacture shall be detailed in the quality documentation. These shall include procedures for the control of off-specification intermediate materials.

• • • 1. Handling, storage, packaging and delivery

The Works' quality documentation shall describe the precautions taken for the protection of the quality of the natural pozzolana and natural activated pozzolanic material while under the responsibility of the manufacturer for the factory. Delivery documentation shall allow traceability to the producing works

• 1. Assessment of the performance of the natural pozzolana and natural activated pozzolanic material

The assessment of the performance of the natural pozzolana and natural activated pozzolanic material shall be based on the evaluation of test results during the initial period, i.e. autocontrol test results and the audit-test results obtained from the first sample and from further samples taken during the initial period.

The duration of the initial period shall be, as a rule, three months.

Sampling and testing shall be carried out as specified in Clause 8.

• 1. Autocontrol testing of samples
     1. Sampling and testing

A system of autocontrol testing shall be operated to demonstrate conformity of the natural pozzolana and natural activated pozzolanic material in accordance with Clause 8. The characteristics to be tested, the testing methods, the minimum frequency of autocontrol testing and the conformity criteria including the statistical evaluation of the autocontrol testing results shall be in accordance with Clause 8.

For natural pozzolana and natural activated pozzolanic material not being dispatched continuously, the frequency of testing and the point of sampling shall be as specified in the Works’ quality documentation. All test data shall be documented.

• • 1. Corrective action

In the event of natural pozzolana or natural activated pozzolanic material yielding a test result not conforming to the single result threshold value conformity criteria specified in Clause 8, the affected quantity shall immediately be determined, appropriate action shall be taken to prevent the dispatch of this quantity, and the affected customer shall be informed if such natural pozzolana and natural activated pozzolanic material has been released.

In addition, the causes of such non-conformity shall immediately be determined, corrective actions shall be taken, and a review of all relevant factory production control procedures shall be undertaken. All such actions and findings shall be appropriately recorded in a report subject to inspection during the management review.

In the event of non-conforming natural pozzolana and natural activated pozzolanic material, the minimum frequency of autocontrol testing of non-conforming characteristics shall be doubled until they conform with the standard, unless it can be demonstrated that adequate measures were taken from the time of the initial occurrence of the non-conformity until its resolution.

• • 1. Measuring and test equipment for autocontrol testing

The equipment used for autocontrol testing shall be regularly checked and calibrated in accordance with procedures and frequencies laid down in the Works' quality documentation. These procedures can include comparison of test results by proficiency testing.

• • 1. Quality records

Records of the autocontrol test results and appropriate records on test equipment shall be retained for at least the period required

• 1. Tasks for the purpose of certification
     1. Initial inspection of the manufacturing plant and of factory production control
        1. Inspection of a new factory

In the case of a new factory, an initial inspection of the factory and of factory production control shall be made, based on information on the factory production control and the equipment to be used to produce and test the natural pozzolana and natural activated pozzolanic material. The inspection shall, amongst other things, verify that the:

a) Works’ quality documentation complies with the requirements of A.2.1.2;

b) equipment used to produce and test the natural pozzolana and natural activated pozzolanic material meet the criteria in A.5.1.3 and A.5.1.4.

• • • 1. Inspection of an existing factory

In case of any significant changes concerning the factory production control and the equipment it shall be decided, based on the importance of the changes to the Works' quality documentation, whether a particular inspection is necessary. In this case any new equipment which has caused a change in the Works' quality documentation which is relevant to the factory production control of natural pozzolana and natural activated pozzolanic material, shall be inspected to verify that it meets the relevant criteria in A.5.1.3 and A.5.1.4.

• • • 1. Criteria for the assessment of the production equipment

The inspection shall assess the suitability of the production equipment in relation to the Works’ quality documentation and in relation to providing the ability to meet the quality targets and control limits. The following criteria shall be considered:

a) The constituents shall be protected against contamination within the factory

b) Equipment shall be provided which is suitable for continuous mass production of natural pozzolana and natural activated pozzolanic material, in particular for adequate grinding and/or selection allowing control of production with sufficient accuracy.

c) Each certified natural pozzolana and natural activated pozzolanic material shall be stored in one or more separate silos, protected to prevent contamination and deterioration. The silos may include or take the form of fully enclosed separated air-tight subdivisions. Silos and/or discharge points shall be clearly marked with an indication of the natural pozzolana or natural activated pozzolanic material and additional identification required.

d) Points where natural pozzolana and natural activated pozzolanic material is released from the factory shall allow samples to be taken in accordance with the methods in EN 196‑7.

• • • 1. Criteria for the assessment of laboratories

The laboratory responsible for carrying out the tests required for internal quality control shall have at least the procedures and the equipment needed to carry out the relevant tests indicated or referred to in the Works' quality documentation (see also A.2.2.2). The laboratory responsible for carrying out autocontrol testing shall have at least the equipment needed to carry out tests for the properties listed in the present document using the test methods indicated (see A.4.3). The laboratories shall be inspected and the ability of the laboratories to provide results within a time and in a manner suitable for the manufacturer’s factory production control shall be verified.

• • 1. Continuing surveillance, assessment and evaluation of factory production control
       1. Inspection of the factory and the factory production control

Inspection shall include checking that any change in the Works’ quality documentation, which is relevant to the factory production control of natural pozzolana and natural activated pozzolanic material, has been reported within one month of its implementation. Inspection shall verify that the factory production control complies with the requirements of A.2 and has been carried out to the Works’ quality documentation. All documents being part of the Works’ quality documentation are subject to the inspection. The inspections of the factory and factory production control shall normally be carried out once a year, and the manufacturer shall be informed in advance when an inspection is to be made. Inspection of depots shall normally be carried out at least every three years. If a natural pozzolana and natural activated pozzolanic material plant operates more than three depots, the frequency of inspections of the depots may be reduced by mutual agreement.

• • • 1. Evaluation of the results of autocontrol testing of samples

Continuing surveillance, assessment and evaluation of the factory production control includes evaluation of the test results of the manufacturer’s autocontrol testing by the third party to check conformity to the statistical conformity criteria and single result threshold values given in the present document.

The number of evaluations of the results of autocontrol testing of samples shall be at least two per year. The timing of the evaluation should be decided in advance.

The length of the control period for evaluation of the autocontrol test results shall be as specified in Clause 8, or equal to the initial period (see 8.1) in the case of a newly certified natural pozzolana and natural activated pozzolanic material. Each evaluation shall be made on the test results obtained on all autocontrol samples of a given natural pozzolana and natural activated pozzolanic material, without selection, taken during the control period preceding the date of the evaluation or during the initial period as the case may be.

The evaluation of the test results should exclude any test result accepted as an outlier, e.g. in the case of identified sampling and testing errors. In the case of managed step changes in product characteristics or in the case of limited production of dispatching runs during the control period, the corresponding data sets may be evaluated separately.

The evaluations may normally be carried out by correspondence and each evaluation shall lead, for the characteristics examined, to a single conclusion in respect of the set of test results as a whole.

It shall be taken into account whether all necessary corrective actions and measures to prevent non-conforming natural pozzolana and natural activated pozzolanic material from delivery have been taken.

• • 1. Audit testing of samples taken at the factory/depot
       1. Sampling

Spot samples shall be taken at the point(s) of release of natural pozzolana and natural activated pozzolanic material from the factory and depots supplied with natural pozzolana and natural activated pozzolanic material by the factory. These are taken principally in order to provide a check on the accuracy of the manufacturer's test results.

The samples taken for audit-testing may be part of the autocontrol testing of samples according to A.4.

The number of samples taken shall be at least six per year for each natural pozzolana and natural activated pozzolanic material dispatched continuously. When a natural pozzolana and natural activated pozzolanic material is not dispatched continuously, this frequency and the point of sampling may be altered by mutual agreement.

The six samples shall be taken as proportional as possible following the actual dispatch of the natural pozzolana and natural activated pozzolanic material, e.g. two samples from bags and four samples from silos.

For audit-testing of natural pozzolana and natural activated pozzolanic material dispatched in a depot, at least every three years one sample of each such natural pozzolana and natural activated pozzolanic material shall be taken at the depot. If a natural pozzolana and natural activated pozzolanic material plant operates more than three depots, the number of samples for audit-testing to be taken at the depots may be reduced by mutual agreement.

The first sample of a natural pozzolana and natural activated pozzolanic material to be certified is used for the assessment of the performance of the natural pozzolana and natural activated pozzolanic material.

The number of samples to be taken during the initial period shall be at least one per month.

• • • 1. Testing

The mechanical, physical and chemical essential characteristics specified for testing in the clause entitled “Assessment and verification of Conformity” in this document shall be determined according to the indicated test methods.

Each sample taken shall be homogenized and divided into three sub-samples. The methods used to take and prepare samples shall be in accordance with EN 196‑7. One sub-sample shall be retained by the manufacturer for testing and one shall be packed, sealed, clearly labelled and forwarded to the laboratory responsible for audit-testing. The third sub-sample shall be sealed and retained by the manufacturer for a minimum period of three months. It is intended for use if:

a) one of the first two sub-samples is lost, deteriorates or becomes contaminated;

b) further testing is needed in the event of a dispute.

The first two sub-samples are intended for testing at the manufacturer laboratory and at the laboratory responsible for audit-testing, respectively, for the required characteristics as listed in this document, using the test methods indicated in that standard.

• • • 1. Evaluation of test results

The results obtained shall be evaluated. The procedures specified in Annex C shall be used for the evaluation of the representativeness and accuracy of the 28-day and 90-day activity index test results.

The results obtained consist of single values with an uncertainty associated. For evaluation, only the obtained test result shall be considered without taking into account the associated uncertainty of measurement, as this is implicitly covered by the Assessment and Verification of Conformity procedures.

• • 1. Reports

Following each evaluation, inspection and assessment, a confidential report shall be prepared and shall be sent to the manufacturer.

• • 1. Actions to be taken in the event of non-conformity
       1. Following inspection of the factory production control and evaluation of the results of autocontrol testing

The reports made following the assessment of the factory production control (see A.5.2.1) and the evaluation of the results of the autocontrol testing (see A.5.2.2) shall form the basis for any decisions/actions and shall be considered on a case-by-case basis.

In the event of non-compliances of the factory production control, appropriate decisions/actions shall be taken to ensure that the factory production control is correctly applied. Cancellation of the certificates may be considered in the event of a continuing non-conformity of the factory production control.

• • • 1. Following evaluation of the results of the audit-testing

If comparisons carried out of 28-day and 90-day activity index according to C.3 show deviations indicating sampling or testing errors, the reasons shall be identified. Any differences in characteristics which could lead to non-conformity should be identified and appropriate action should be taken. It shall be established whether appropriate actions have been taken to correct for these deviations and any further actions required shall be specified including, if necessary, correction of all relevant results.

If the results of the audit-testing include a test result outside the specified characteristic value, the results of the autocontrol testing shall be evaluated over an appropriate period. If the autocontrol testing is found to be satisfactory no further action is necessary. If the autocontrol testing confirms the findings of the audit-testing, necessary actions shall be taken.

• 1. Procedure for the certification of conformity of the product

When a manufacturer applies for certification of conformity of a natural pozzolana or natural activated pozzolanic material an initial inspection of the factory and the factory product control (if required) (see A.5.1) shall be arranged.

Given that the inspection (if any) indicates that the requirements of A.5.1 and that the results of the testing of the first sample taken during the initial period meet the Assessment and Verification of Conformity criteria of this document, a certificate of conformity of the product shall be issued.

If this evaluation is satisfactory, the certificate remains valid unless cancelled (or withdrawn as a result of actions taken in the event of non-conformity (see A.5.5). However, the period of validity of a certificate of performance might be limited.

In the event that a manufacturer permanently ceases production of a certified natural pozzolana or natural activated pozzolanic material, the relevant certificate of conformity of the product shall be cancelled. A manufacturer shall be deemed to have permanently ceased production of a natural pozzolana or natural activated pozzolanic material when a period of twelve months has elapsed since the date of the last autocontrol sample.

1. 
   (informative)
   
   Attestation of conformity

For the attestation of conformity of natural pozzolana or natural activated pozzolanic material covered by this document the procedure specified in Clause A.6 shall apply. When compliance with the conditions of this document is achieved, a certificate of conformity should be issued. The certificate shall include:

— name, address and identification number of the certification body;

— standard designation of the natural pozzolana or natural activated pozzolanic material;

— name and address of the manufacturer and place of production;

— provisions to which the product conforms;

— conditions of validity of the certificate, where applicable;

— the number of the certificate;

— name of, and position held by, the person empowered to sign the certificate.

1. 
   (informative)
   
   Evaluation of the representativeness and the accuracy of the 28-day activity index test results
   1. General

This annex describes the procedures that shall be used to evaluate the representativeness and the accuracy of the 28-day activity index test results. The evaluation shall preferably be made in connection with the routine yearly inspection.

• 1. Sets of results considered

The evaluation procedure assesses the following three sets of test results:

The number of results in each of the sets B and C are at least six. They should be equally distributed throughout the period under consideration.

• 1. Evaluation procedure
     1. Introduction

The evaluation procedure includes two parts, as described in C.3.3 and C.3.4.

• • 1. Symbols

The symbols used in C.3.3 and C.3.4 are given in Table 5.

• • 1. Evaluation of whether set A and set B belong to the same population (sampling error check)

a) Where |M_A - M_B| ≤ 4 %, the two sets of results may be considered to belong to the same population

b) Where |M_A - M_B| > 4 %

— if |M_A - M_B| ≤ 2,58 × S_A / (N_B)^1/2

— the two sets of results are considered to belong to the same population,

— if | M_A - M_B | > 2,58 × S_A / (N_B)^1/2

— the reason shall be identified by the manufacturer (in this case the two sets of test results can be considered to belong to different populations with a confidence level of 99 % as described in ISO 2854:1976).

• • 1. Comparison between set B and set C in order to check the accuracy of the autocontrol testing (testing error check)

Two conditions should be satisfied:

a) S_D ≤ 7 %

b) |M_B - M_C| ≤ 8 %

If either of these conditions are not satisfied, the reason shall be identified.

Table C.1 — Symbols

Bibliography

EN 206:2013+A2:2021, Concrete — Specification, performance, production and conformity

EN 413‑2, Masonry cement — Part 2: Test methods

EN 934‑2, Admixtures for concrete, mortar and grout — Part 2: Concrete admixtures — Definitions, requirements, conformity, marking and labelling

ISO 2854:1976, Statistical interpretation of data — Techniques of estimation and tests relating to means and variances

ISO 9001, Quality management systems — Requirements