An air filter is designed to collect particulates from the air (i.e. dust and dirt). Airborne contaminants, such as viruses, bacteria, mold, chemical agents, and VOCs pass through even a high efficiency filter, like sand through a tennis racket. UV air purification systems are designed to destroy the DNA structure of microorganisms through sterilization, as well as change the molecular structure of contaminants through photo-oxidation destroying both biological and chemical contaminants, including odors.