 Typically a rinse-aid, a chemical to reduce surface tension of the water, is used to reduce water spots from hard water or other reasons.In addition to domestic units, industrial dishwashers are available for use in commercial establishments such as hotels and restaurants, where many dishes must be cleaned.Washing is conducted with temperatures of and sanitation is achieved by either the use of a booster heater that will provide an "final rinse" temperature or through the use of a chemical sanitizer.