Ultraviolet purification is a proven technology (EPA approved) that can protect your family from waterborne disease-causing microorganisms, such as bacteria, viruses, algae, and fungi. Ultraviolet (UV) disinfection works by delivering concentrated amounts of UV light energy to the reproductive mechanism of the microbe, effectively killing it. As water passes through the UV chamber, it instantly disinfects it. The only homeowner maintenance is to replace the bulb once per year.