Ultraviolet (UV) light at wavelengths 250-270 nanometers has the ability to scramble DNA in living cells preventing them from reproducing and often stopping other cellular functions. It does not form potential unhealthy disinfection by-products (DBP) as halogen disinfections often do in the presence of organic compounds. However, being a light wave that travels in straight lines, pathogens can hide in the shadow of solid particles in the water stream. Orival filters remove those particles exposing pathogens to the disinfecting UV rays.