Purified water is used in the pharmaceutical industry. Water of this grade is widely used as a raw material, ingredient, and solvent in the processing, formulation, and manufacture of pharmaceutical products, active pharmaceutical ingredients (APIs) and intermediates, compendial articles, and analytical reagents.

The microbiological content of the water is of importance and the water must be regularly monitored and tested to show that it remains within microbiological control.

Safety: Purified water is water that has been mechanically filtered or processed to remove impurities and make it suitable for use.