This European Standard is applicable to silver nitrate and silver sulfate for the preservation of water intended for human consumption in intermittent applications in water supply plants, including their pipeline networks (small-size plants); water for the preparation of foodstuffs; and other water which is stored in packaged form or kept in enclosed systems (for example, water supply systems in land, water and airborne vehicles). The purpose of adding silver salts is to prevent the detrimental proliferation of micro-organisms in water during storage or in enclosed supply systems. This European Standard describes the characteristics of silver salts and specifies the requirements for silver salts and gives reference to the analytical methods. It gives information on their use in water treatment. It also determines the rules relating to safe handling and use of silver salts (see Annex B).