This TIR addresses how to determine the water needs for reprocessing a particular device and how to generate the water to meet those requirements. Subjects include a) guidelines for selecting the water quality necessary for the reprocessing of categories of medical devices; b) water treatment equipment; c) water distribution and storage; d) quality control procedures for monitoring water quality; e) strategies for bacterial control; f) environmental considerations; and g) personnel considerations. The TIR also provides definitions of terms, a bibliography, and informative annexes.