An important part of the air purification system, a UV bulb destroys germs and bacteria.UV reduces the growth of odour-causing microbes on the surface of the air purifier filter.Microscopic airborne organisms get trapped in air filters, which could multiply if left untreated.When bacteria, viruses, and protozoa are exposed to the germicidal wavelengths of UV light, they are rendered incapable of reproducing and infecting.Indicator light on the air purifier glows red when it’s time to replace the bulb.