This document is applicable to iron (III) chloride (a), iron (III) chloride hexahydrate (b), iron (III) chloride solution (c) used for treatment of water intended for human consumption. It describes the characteristics and specifies the requirements and the corresponding analytical methods for iron (III) chlorides (a), (b) and (c) (analytical methods are given in Annex B) and gives information for their use in water treatment.