(EMEA) Water for the preparation of medicines for parenteral administration when water is used as a vehicle (water for injection in bulk) and for dissolving or diluting substances or preparations for parenteral administration before use (sterilized water for injection). Control of the chemical purity of WFI presents few major problems. The critical issue is that of ensuring consistent microbiological quality with respect to removal of bacteria and bacterial endotoxins. Distillation has a long history of reliable performance and can be validated as a unit operation, hence it currently remains the only official method for WFI.WFI in bulk is obtained from water that complies with the regulation on water intended for human consumption laid down by the competent authority, or from purified water, by distillation in an apparatus of which the parts in contact with the water are of neutral glass, quartz or suitable metal and which is fitted with an effective device to prevent the entrainment of droplets. The correct maintenance of the apparatus is essential. During production and storage, appropriate measures are taken to ensure that the total viable aerobic count is adequately controlled and monitored.WFI complies with the tests for Purified water with additional requirements for bacterial endotoxins [not more than (nmt) 0.25 IU endotoxins per ml], conductivity and Total Organic Carbon.