Ultraviolet light has just the right amount of energy to break organic molecular bonds. As micro-organisms pass by the UV rays radiated from the ultraviolet lamp, this bond breakage translates into cellular or genetic damage for micro-organisms, such as germs, viruses, bacteria, fungi (like molds), etc. This results in the destruction of micro-organisms.

The Centers of Disease Control (CDC) recommends the use of ultraviolet light with simultaneous use of HEPA air filters.  They suggests UV lights should be used in buildings for indoor air quality purposes, and states that may be the final line of defense against those diseases that have developed resistance to drugs, such as tuberculosis and others. 

 A study by Air & Waste Management Association found the combination of a HEPA air filter and germicidal UV lamp reduced bacteria by 80% in a 3072 cubic foot chamber.