UV lights reduce the amount of microbes, viruses, germs, and bacteria throughout your home. Since the 1900s, UV light has been used to prevent the spread of diseases. In 1903, Niels Finsen was awarded the Nobel Prize for Medicine for using UV against lupus vulgaris, tuberculosis of the skin. Using UV lights to treat water dates back to 1916 and is commonly used today to treat drinking water, wastewater, and indoor air.