This International Standard specifies requirements for appliances for household and similar purposes to prevent the backsiphonage of non-potable water into the water mains. It also specifies requirements for hose-sets used for connecting such appliances to the water mains that supply water at a pressure not exceeding 1 MPa. NOTE 1 Examples of similar purposes are the installation of appliances in canteens, restaurants, launderettes and communal flats. NOTE 2 This standard does not apply to - appliances used for dry cleaning; - appliances for medical purposes; - appliances intended for industrial purposes; - water heaters that are an integral part of the water supply system; - water coolers that are an integral part of the water supply system. NOTE 3 The connection of the appliance to the water mains may be temporary or permanent. NOTE 4 When reference is made to the water mains, water supplied from a cistern or similar system is also included. NOTE 5 Many countries have requirements concerning the prevention of contamination of potable water as a result of contact with unsuitable materials upstream of a backflow prevention device.