prEN 12904

• Abstract:

  This document is applicable to silica sand and silica gravel used for treatment of water intended for human consumption. It describes the characteristics of silica sand and silica gravel and specifies the requirements and the corresponding test methods for silica sand and silica gravel. It gives information on their use in water treatment.

• Status: Not Published
• Publication Date: 09-Dec-2027
• ICS: 71.100.80 - Chemicals for purification of water
• Technical Committee: CEN/TC 164 - Water supply
• Drafting Committee: CEN/TC 164/WG 9 - Drinking water treatment
• Current Stage: 4020 - Submission to enquiry - Enquiry
• Start Date: 08-Oct-2026
• Due Date: 27-Aug-2026
• Completion Date: 08-Oct-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 12904:2026 - Products used for treatment of water intended for human consumption - Silica sand and silica gravel

• Revises: EN 12904:2005 - Products used for treatment of water intended for human consumption - Silica sand and silica gravel
• Effective Date: 29-Jun-2022

prEN 12904 is a CEN draft European standard for silica sand and silica gravel used to treat water intended for human consumption. It specifies how these materials are described, what physical and chemical requirements they shall meet, how they are tested, and what information accompanies delivery for water-treatment use.

What does prEN 12904 specify?

prEN 12904 applies to silica sand and silica gravel used in treatment of water intended for human consumption. It covers product description, physical properties, chemical properties, test methods, and information on use in water treatment.

The document is organized into eight clauses plus one informative annex:

• Clause 1 - scope
• Clause 2 - normative references
• Clause 3 - terms, definitions and symbols
• Clause 4 - description and identification
• Clause 5 - physical properties
• Clause 6 - chemical properties
• Clause 7 - test methods
• Clause 8 - labelling, transportation and storage
• Annex A - general information on silica sand and silica gravel

Annex A supports the technical clauses with background information on origin, typical properties, use, hydraulic behavior, handling, and emergency actions.

What are the key requirements of prEN 12904?

prEN 12904 focuses on the characteristics that matter for filter performance, product consistency, and safe handling in drinking-water treatment. The most important requirements are in Clauses 4 to 8.

Product identity and form

prEN 12904 identifies the product as silica, silicon dioxide (SiO2), with the common names silica sand and silica gravel. The material is supplied in different particle size ranges, so buyers and users need to specify the grade that matches the filter design.

Physical properties

prEN 12904 describes the material as a granular product that may be grey/white, yellow, or multicoloured, and it shall be generally homogeneous and free from visible extraneous matter. Clause 5 also sets particle size distribution expectations and bulk density ranges for loose and packed material. In practice, this matters because particle size and density influence filtration rate, bed depth, head loss, and washing behavior.

Clause 5 allows particle size to be described either by effective size, uniformity coefficient, and minimum size, or by particle size range with permitted oversize and undersize fractions. The permitted fractions depend on the application, with different expectations for multi-media filters, single media filters, and support layers. That means the user has to match the supplier’s size declaration to the intended filter duty.

Chemical purity

prEN 12904 sets minimum purity requirements and limits for impurities commonly present in the product. Clause 6 gives composition limits for SiO2 and acid-soluble material, and it requires notification when other impurities, by-products, or additives are present in significant quantities. For users, this means the product must be selected with awareness of raw water quality, dosage, and any extra constituents that may affect treatment.

Sampling and test methods

prEN 12904 requires sampling at the production site for conformity assessment, because transport and handling can change the sample. Clause 7 refers to EN 12902 for laboratory sample preparation and for the test methods for particle size distribution, bulk density, silica content, and acid-soluble material. This keeps acceptance testing tied to the point of manufacture rather than to a possibly altered delivery sample.

Delivery, marking, and storage

prEN 12904 allows delivery in bags, big bags, or bulk, but the means of delivery shall not have been used previously for another product unless cleaned and prepared. Clause 8 also requires marking with the product name, trade name, grade, type, net mass, supplier or manufacturer details, and a statement of conformity to EN 12904. Storage is covered as dry and clean conditions with protection from direct sunlight and UV radiation.

What terms does prEN 12904 define?

prEN 12904 uses the terms and symbols from EN 12901, and the following key terms are central to the document:

• Silica sand - a silica-based granular material used as a filter or support medium in water treatment.
• Silica gravel - a coarser silica-based granular material used in the same treatment applications.
• Effective size - a particle-size descriptor used to characterize the media for filtration behavior.
• Uniformity coefficient - a measure used with particle size distribution to describe how even the grading is.
• Bulk density loose - the density of the material in an untamped, free-flowing state.
• Bulk density packed - the density after packing, used to characterize how the material settles in storage or application.
• Acid-soluble material - the soluble fraction used as an indicator of impurities in the product.
• SiO2 - silicon dioxide, the chemical identity of the silica material.

Who uses prEN 12904?

prEN 12904 is used by manufacturers and suppliers of silica sand and silica gravel, water-treatment engineers, and laboratories testing filter media. It is also relevant to buyers, quality managers, and operators of open or closed, single or multi-media filters, including slow sand filtration systems. In practice, they use it to specify a product, verify conformity, label deliveries, and assess whether the media suits a drinking-water treatment application.

What changed in prEN 12904 from the previous edition?

prEN 12904 will supersede EN 12904:2005. The foreword states two significant technical changes: an update to the reference to the EU Directive on drinking water, and an update to the Regulation on classification, labelling and packaging of substances and mixtures, including REACH.

Which standards are used with prEN 12904?

prEN 12904 relies on two normative references:

• EN 12901 - provides the terms, definitions, and symbols used throughout the document.
• EN 12902 - provides the methods of test and the procedures used for sampling and analysis.

These references are important because prEN 12904 uses EN 12902 for laboratory preparation and measurement, and EN 12901 for the terminology framework.

What does the prEN 12904 document contain?

prEN 12904 contains a product description, physical and chemical property requirements, test methods, and delivery and storage instructions. Clause 5 and Clause 6 are the main technical requirement clauses, while Clause 7 defines how to sample and analyze the product for conformity assessment. Clause 8 gives practical requirements for packaging, marking, transport status, and storage conditions.

Annex A adds background material that helps users interpret the standard in practice. It includes the product’s origin and manufacturing process, typical chemical composition in Table A.1, example particle size ranges in Table A.2, hydraulic characteristics, safe handling advice, and first-aid and spill guidance.

SLOVENSKI STANDARD
01-december-2026
Proizvodi, ki se uporabljajo za pripravo pitne vode - Kremenov pesek in kremenov
prod
Products used for treatment of water intended for human consumption - Silica sand and
silica gravel
Produkte zur Aufbereitung von Wasser für den menschlichen Gebrauch - Quarzsand und
Quarzkies
Produits utilisés pour le traitement de l'eau destinée à la consommation humaine - Sable
et gravier de quartz
Ta slovenski standard je istoveten z: prEN 12904
ICS:
13.060.20 Pitna voda Drinking water
71.100.80 Kemikalije za čiščenje vode Chemicals for purification of
water
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

DRAFT
EUROPEAN STANDARD
NORME EUROPÉENNE
EUROPÄISCHE NORM
October 2026
ICS Will supersede EN 12904:2005
English Version
Products used for treatment of water intended for human
consumption - Silica sand and silica gravel
Produits utilisés pour le traitement de l'eau destinée à Produkte zur Aufbereitung von Wasser für den
la consommation humaine - Sable et gravier de quartz menschlichen Gebrauch - Quarzsand und Quarzkies
This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee
CEN/TC 164.
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 12904:2026 E
worldwide for CEN national Members.

Contents Page
European foreword . 3
Introduction . 4
1 Scope . 5
2 Normative references . 5
3 Terms, definitions and symbols . 5
4 Description . 5
4.1 Identification . 5
4.1.1 Chemical name(s) . 5
4.1.2 Synonym or common names . 5
4.2 Commercial forms . 5
5 Physical properties . 5
5.1 Appearance . 5
5.2 Particle size distribution . 6
5.3 Density . 6
5.3.1 Bulk density loose . 6
5.3.2 Bulk density packed . 6
6 Chemical properties . 6
7 Test methods . 7
7.1 Sampling . 7
7.2 Analysis . 7
7.2.1 Particle size distribution . 7
7.2.2 Bulk density loose . 7
7.2.3 Bulk density packed . 7
7.2.4 Content of silica . 7
7.2.5 Acid-soluble material . 7
8 Labelling, transportation and storage. 8
8.1 Means of delivery . 8
8.2 Risk and safety labelling . 8
8.3 Transportation regulations and labelling . 8
8.4 Marking . 8
8.5 Storage — Long term chemical stability . 8
Annex A (informative) General information on silica sand and silica gravel . 9
Bibliography . 13

European foreword
This document (prEN 12904:2026) has been prepared by Technical Committee CEN/TC 164 “Water
supply”, the secretariat of which is held by AFNOR.
This document is currently submitted to the CEN Enquiry.
This document will supersede EN 12904:2005.
a) Update the reference to EU Directive in order to take account of the last Directive in force (see [1]).
b) Update the Regulation of the European Parliament and of the Council of 16 December 2008 on
classification, labelling and packaging of substances and mixtures, amending and repealing
Directives 67/548/EEC and 1999/45/EC, and amending Regulation (EC) No 1907/2006 (REACH).
This document has been prepared under a standardization request addressed to CEN by the European
Commission. The Standing Committee of the EFTA States subsequently approves these requests for its
Member States.
Introduction
In respect of potential adverse effects on the quality of water intended for human consumption, caused
by the product covered by this document:
a) This document provides no information as to whether the product may be used without restriction
in any of the Member States of the EU or EFTA;
b) It should be noted that, while awaiting the adoption of verifiable European criteria, existing national
regulations concerning the use and/or the characteristics of this product remain in force.
NOTE Conformity with the document does not confer or imply acceptance or approval of the product in any
of the Member States of the EU or EFTA. The use of the product covered by this document is subject to regulation
or control by National Authorities.
1 Scope
This document is applicable to silica sand and silica gravel used for treatment of water intended for
human consumption. It describes the characteristics of silica sand and silica gravel and specifies the
requirements and the corresponding test methods for silica sand and silica gravel. It gives information
on their use in water treatment.
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 12901, Products used for treatment of water intended for human consumption - Inorganic supporting
and filtering materials - Definitions
EN 12902, Products used for treatment of water intended for human consumption - Inorganic supporting
and filtering materials - Methods of test
3 Terms, definitions and symbols
For the purpose of this document, the terms, definitions and symbols given in EN 12901 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 Description
4.1 Identification
4.1.1 Chemical name(s)
Silica, silicon dioxide (SiO ).
4.1.2 Synonym or common names
Silica sand and silica gravel.
4.2 Commercial forms
Silica sand and silica gravel according to this documen
...