This document is applicable to polyaluminium hydroxide silicate sulfate used for treatment of water intended for human consumption. It describes the characteristics of polyaluminium hydroxide silicate sulfate and specifies the requirements for polyaluminium hydroxide silicate sulfate and refers to the corresponding analytical methods. It gives information on its use in water treatment. It also determines the rules to safe handling and use of polyaluminium hydroxide silicate sulfate (see annex B).