Abstract: Method and apparatus for a continuous or intermittent supply of ozonated fluid, particularly water, from a closed loop system for sanitation, consumption, and other purposes. A preferred embodiment of the apparatus aspect of the invention comprises an ozone generator, an ozone entraining system, and a closed loop water circuit. The closed loop circuit permits continuous recirculation and ozonation of fluid not drawn from the system for use. Optionally the apparatus provides for the removal of an arbitrary fraction of ozonized or ozonated water to any arbitrary service application, such as food- or medical-equipment sterilization, with simultaneous addition of makeup water to maintain a relatively constant mass balance in the overall system, so that ozonized water is continuously available. Unused water is stored indefinitely in a reservior. Further options include venting of off gases and destruction of any ozone gas fraction thereof.