The sonic shower is a technology used by Federation citizens for personal grooming. The system uses sonic vibrations to dissolve dirt, removing it from the skin in the process. Many consider taking a sonic shower to be a relaxing experience1, and Dax thought it could make people feel better.2Earth ships of the 2150s used water-based cleaning systems3, but sonic showers were in use aboard Federation Starships by the 2271.4 Federation sonic shower systems used an acoustic inverter; if this malfunctioned the effect on the user was considered to be unpleasant.5
Humans of the 2370s regarded sonic showers as almost a basic necessity, to the point where Quark considered that the removal of showers and other such comforts over a prolonged period would make most Humans become "as nasty and violent as the most bloodthirsty Klingon".6
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