Disinfection of Airborne Organisms by Ultraviolet-C Radiation and Sunlight

The intentional or accidental release of bioaerosols and resulting infection by the inhalation route of large populations is a major concern for both public health and national security reasons. Various methods can be employed to disinfect and/or remove bioaerosols in public settings; however, the use of untraviolet (UV) radiation is proven to be an effective and inexpensive approach to inactivate airborne microorganisms. Sunlight is relied upon to disinfect outdoor air while strategically placed UV-C light is used in indoor settings. This chapter provides an overview on disinfection of airborne microorganisms due to UV-C radiation or to sunlight exposure, and the effectiveness of UV light on aerosolized organisms. This chapter also discusses the biological aerosol generation techniques and UV-C exposure methodology used at US Army Edgewood Chemical Biological Center (ECBC) as an example for researchers to compare to their own experimental conditions and as guidance to those newer to the field. Understanding the mechanisms of UV-based disinfection will assist in predicting disease spread and the role of natural sunlight and of artificial UV-C light on reducing the concentration of infectious agents suspended in aerosols.