 With new advances in detergents, lower water temperatures (50–55 °C / 122–131 °F) are needed to prevent premature decay of the enzymes used to eat the grease and other build-ups on the dishes.In the US, residential dishwashers can be certified to a NSF International testing protocol which confirms the cleaning and sanitation performance of the unit.The heat inside the dishwasher dries the contents after the final hot rinse; the final rinse adds a small amount of rinse-aid to the hot water, as this improves drying significantly by reducing the inherent surface tension of the water.