【正文】 n a nonpotable system in which the pressure exceeds the pressure in the potable water system. Page 8 EN 1717:2020 169。 ? special uses relating to similar consumers where products are used with low concentrations and presenting no danger for human health (for example authorized water conditioning, air conditioning)。 BSI 012020 Licensed Copy: Institute Of Technology Tallaght, Institute of Technology, Tue May 08 10:39:47 GMT+00:00 2007, Uncontrolled Copy, (c) BSI Foreword This European Standard 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of an identical text or by endorsement, at the latest by month of May 2020, and conflicting national standards shall be withdrawn at the latest by May 2020. According to the CEN/CENELEC Internal Regulations, the national standards anizations of the following countries are bound to implement this European Standard: Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and the United Kingdom. Annex A of this European Standard is normative, the Annexes B and C are informative. Introduction In respect of potential adverse effects on the quality of water intended for human consumption, caused by the products covered by this standard: 1) this standard provides no information as to whether the products may be used without restriction in any of the Member state of the EU or EFTA。 I S C H ES KOM I T E E F 220。ckflie223。r ieurs et exigences g233。ISCHE NORM EN 1717 November 2020 ICS 。, or by using the 170。 present to the responsible European mittee any enquiries on the interpretation, or proposals for change, and keep the UK interests informed。| | | | | | | | | 1717:2020 | Licensed Copy: Institute Of Technology Tallaght, Institute of Technology, Tue May 08 10:39:47 GMT+00:00 2007, Uncontrolled Copy, (c) BSI BRITISH STANDARD Protection against pollution of potable water in water installations and general requirements of devices to prevent pollution by backflow The European Standard EN 1717:2020 has the status of a British Standard ICS 。 208。International Standards Correspondence Index186。ENNE EUROP196。seaux int233。tung von Trinkwasserverunreinigungen durch R252。E N D E NOR M A L I S A T I ON EUR O P 196。 BSI 012020 Licensed Copy: Institute Of Technology Tallaght, Institute of Technology, Tue May 08 10:39:47 GMT+00:00 2007, Uncontrolled Copy, (c) BSI Contents Page Foreword............................................................................................................................ 3 Introduction ....................................................................................................................... 3 1 Scope ...................................................................................................................... 4 2 Normative references............................................................................................. 4 3 Terms and definitions ............................................................................................ 4 4 Pollution of potable water: general observations ............................................... 6 Backflow of used water.......................................................................................... 6 Connection.............................................................................................................. 6 External influences ................................................................................................ 7 Materials.................................................................................................................. 7 Stagnation ............................................................................................................... 7 Harm caused by inadequate or improper maintenance ...................................... 7 5 Analysis method of the risks at the point of use and choice of protection ...... 7 General remarks ..................................................................................................... 7 Determination of fluid categories which are or could be in contact with potable water .......................................................................................................... 8 Determination of the installation characteristics ................................................ 9 Separation by single or double walls ................................................................... 9 Air break to drain...................................................................................................10 Installation matrix..................................................................................................10 Protection units .....................................................................................................10 Matrix of the protection units appropriate to fluid categories...........................12 6 Point of use protection for equipment at the drawoff point for domestic uses .....................................................................................................................