SIST EN 1717:2025
(Main)Protection against pollution of water intended for human consumption in potable water installations and general requirements for devices to prevent pollution by backflow
Protection against pollution of water intended for human consumption in potable water installations and general requirements for devices to prevent pollution by backflow
This document specifies an analysing methodology for protecting potable water in potable water installations within and outside buildings but within premises from the risk of pollution by backflow of non-potable water and gives recommendations on the design, risk analysis, backflow prevention devices and their installation methods (see Figure 1 and Figure 2).
This methodology is also intended to be used outside premises for all water systems connected to a potable water distribution system up to and including the point of use (see Figure 3).
The product standards for the specific backflow prevention devices or arrangements are intended to be used in conjunction with this document. For the development of new devices or systems, this document is intended to be used as a reference to establish the necessary level of backflow protection.
Schutz des Trinkwassers vor Verunreinigungen in Trinkwasser-Installationen und allgemeine Anforderungen an Sicherungseinrichtungen zur Verhütung von Trinkwasserverunreinigungen durch Rückfließen
Dieses Dokument legt eine Analysemethodik fest, um Trinkwasser in Trinkwasserinstallationen innerhalb von Gebäuden und außerhalb von Gebäuden, aber innerhalb von Grundstücken vor dem Risiko von Verunreinigungen durch das Rückfließen von Nichttrinkwasser zu schützen, und es gibt Empfehlungen zur Konstruktion, zur Risikoanalyse, zu Sicherungseinrichtungen gegen Rückfließen und zu deren Einbauverfahren (siehe Bild 1 und Bild 2).
Diese Methodik ist auch zur Anwendung außerhalb von Grundstücken bei allen Installationen gedacht, die mit einem Trinkwasser-Verteilungssystem verbunden sind, bis einschließlich der Entnahmestelle (siehe Bild 3).
Es ist vorgesehen, die Produktnormen für die jeweiligen Armaturen oder Vorrichtungen zur Verhinderung des Rückfließens zusammen mit diesem Dokument zu verwenden. Bei der Entwicklung neuer Einrichtungen oder Systeme ist dieses Dokument dazu vorgesehen, als Referenz für die Ermittlung des erforderlichen Niveaus der Absicherung gegen Rückfließen zu dienen.
Protection contre la pollution de l’eau destinée à la consommation humaine dans les installations d’eau potable et exigences générales applicables aux dispositifs de protection contre la pollution par retour
Le présent document spécifie une méthode d’analyse pour la protection de l’eau potable dans des installations d’eau potable à l’intérieur et à l’extérieur des bâtiments, mais aussi dans les locaux, contre le risque de pollution par retour de l’eau non potable. Il donne également des recommandations sur la conception, l’analyse des risques, les dispositifs de protection contre les retours et leurs méthodes d’installation (voir Figures 1 et 2).
Cette méthode est également destinée à être utilisée en dehors des locaux, dans tous les réseaux d’eau raccordés à un réseau de distribution d’eau potable jusqu’au point d’utilisation inclus (voir Figure 3).
Les normes de produits concernant les dispositifs ou les systèmes de protection contre les retours spécifiques sont destinées à être utilisées conjointement avec le présent document. Pour le développement de nouveaux dispositifs ou systèmes, le présent document est destiné à être utilisé comme référence pour établir le niveau de protection sanitaire nécessaire.
Varovanje pitne vode pred onesnaževanjem v napeljavah za pitno vodo in splošne zahteve za varovala za preprečitev onesnaževanja pitne vode zaradi povratnega toka
General Information
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Standards Content (Sample)
SLOVENSKI STANDARD
01-oktober-2025
Varovanje pitne vode pred onesnaževanjem v napeljavah za pitno vodo in splošne
zahteve za varovala za preprečitev onesnaževanja pitne vode zaradi povratnega
toka
Protection against pollution of water intended for human consumption in potable water
installations and general requirements for devices to prevent pollution by backflow
Schutz des Trinkwassers vor Verunreinigungen in Trinkwasser-Installationen und
allgemeine Anforderungen an Sicherungseinrichtungen zur Verhütung von
Trinkwasserverunreinigungen durch Rückfließen
Protection contre la pollution de l’eau destinée à la consommation humaine dans les
installations d’eau potable et exigences générales applicables aux dispositifs de
protection contre la pollution par retour
Ta slovenski standard je istoveten z: EN 1717:2025
ICS:
13.060.20 Pitna voda Drinking water
91.140.60 Sistemi za oskrbo z vodo Water supply systems
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
EN 1717
EUROPEAN STANDARD
NORME EUROPÉENNE
August 2025
EUROPÄISCHE NORM
ICS 13.060.20; 23.060.01; 91.140.60 Supersedes EN 1717:2000
English Version
Protection against pollution of water intended for human
consumption in potable water installations and general
requirements for devices to prevent pollution by backflow
Protection contre la pollution de l'eau destinée à la Schutz des Trinkwassers vor Verunreinigungen in
consommation humaine dans les installations d'eau Trinkwasser-Installationen und allgemeine
potable et exigences générales applicables aux Anforderungen an Sicherungseinrichtungen zur
dispositifs de protection contre la pollution par retour Verhütung von Trinkwasserverunreinigungen durch
Rückfließen
This European Standard was approved by CEN on 5 June 2025.
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. Up-to-date lists and bibliographical references
concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN
member.
This European Standard exists 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.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2025 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 1717:2025 E
worldwide for CEN national Members.
Contents Page
European foreword . 4
Introduction . 5
1 Scope . 6
2 Normative references . 7
3 Terms and definitions . 8
4 Pollution of potable water: general observations . 11
4.1 General. 11
4.2 Backflow of non-potable water . 11
4.3 Cross-connection . 11
4.4 External influences . 11
4.5 Materials . 11
4.6 Stagnation . 12
4.7 Inadequate or improper maintenance . 12
5 Analysis method of the pollution risks and choice of protection . 12
5.1 General remarks . 12
5.2 Determination of fluid categories . 12
5.2.1 General. 12
5.2.2 Category 1 . 12
5.2.3 Category 2 . 12
5.2.4 Category 3 . 13
5.2.5 Category 4 . 13
5.2.6 Category 5 . 13
5.2.7 Mixture of fluids . 13
5.3 Determination of the installation characteristics . 13
5.3.1 General. 13
5.3.2 Pressure . 13
5.3.3 Connections . 14
5.3.4 Risk attenuation . 14
5.4 Separation by single or double walls . 14
5.4.1 General. 14
5.4.2 Rules . 14
5.4.3 Leakage test on double-wall-separation . 15
5.5 Air break to drain . 15
5.6 Installation matrix . 15
5.7 Protection units . 16
5.7.1 Generalities . 16
5.7.2 Functional requirements for protection units against pollution . 16
5.7.3 Description and installation requirements of the protection units . 17
5.8 Matrix of the protection units appropriate to fluid categories . 17
5.9 Summary of analysis method . 18
6 Protection of equipment installed at the draw-off point (Point-of-Use systems) . 19
6.1 General. 19
6.2 Special provisions for domestic Point-of-Use systems . 19
7 Protection at the connection point to the public potable water system . 20
8 Air break to drain . 20
8.1 General . 20
8.2 Minimum requirements . 21
8.3 Calculation of air inlets or overflow openings . 22
Annex A (normative) Reference list of the protection units . 23
Annex B (informative) Guide table for determining the fluid category from which protection
is required . 55
Annex C (informative) Example for the selection of protection devices for the domestic and
non-domestic use . 57
C.1 Example — Care lift bath. 57
C.2 Example — Utilization of rain water . 58
C.3 Example — Detergent dosing system . 59
C.4 Example — Filling station for heating systems . 61
C.5 Example — Animal drinking trough . 62
C.6 Example — Flushing compressor for sewages systems . 63
C.7 Example — Tank filling for vehicles with water tanks . 64
Bibliography . 66
European foreword
This document (EN 1717:2025) has been prepared by Technical Committee CEN/TC 164 “Water supply”,
the secretariat of which is held by AFNOR.
This European Standard shall be given the status of a national standard, either by publication of an
identical text or by endorsement, at the latest by February 2026, and conflicting national standards shall
be withdrawn at the latest by February 2026.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
This document supersedes EN 1717:2000.
This document includes the following significant technical changes with respect to EN 1717:2000:
— the Scope has been made more precise, extended and revised;
— terms and definitions have been amended;
— all Figures have been updated and re-drawn;
— Table 2 has been updated;
— Clause “Air break to drain” has been revised;
— Annex A and Annex B have been completely revised;
— Annex C has been revised and provides application examples.
Any feedback and questions on this document should be directed to the users’ national standards body.
A complete listing of these bodies can be found on the CEN website.
According to the CEN-CENELEC Internal Regulations, the national standards organisations of the
following countries are bound to implement this European Standard: 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 the United
Kingdom.
Introduction
In respect of potential adverse effects on the quality of water intended for human consumption, caused
by the products covered by this document, it provides no information as to whether the products may be
used without restriction in any of the Member state of the EU or EFTA;
NOTE While awaiting the adoption of verifiable European criteria, attention is also drawn to national
regulations that can apply.
The UK Matrix of the protection units appropriate to fluid categories (Table 2) and the determination of
fluid categories (5.2
...
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