While UVGI is an excellent surface disinfectant, it does not penetrate surfaces and cannot disinfect soiled surfaces. The inability of the UV radiant energy to reach shadowed recesses of surfaces or to penetrate coverings like dust and other matter may negatively affect disinfection. For these reasons, UVGI is typically used as a supplemental control measure for disinfection. A 2005 published study concluded that UVGI lamps could have some effect on the spread of infectious respiratory diseases, but there was inadequate evidence to support recommending its wide use. The CDC recognizes that UVGI has several potential applications but also has limitations and possible safety issues.[9,10,11]
 Lee T, Jordan NN, Sanchez JL, Gaydos JC. Selected nonvaccine interventions to prevent infectious acute respiratory disease. Am J Prev Med. 2005;28(3):305-16.
 Sehulster L, Chinn RYW. Guidelines for environmental infection control in healthcare facilities – Recommendations of the Centers for Disease Control and the Healthcare Infection Control Practices Advisory Committee (HICPAC). 2003;52(RR10):1-42.
 Jensen PA, Lambert LA, Lademarco MF, Ridzon R. 2005. Guidelines for preventing the transmission of Mycobacterium tuberculosis in health-care settings, 2005. Morbid Mortal Weekly Rep. 2005;54(RR17):1-141.
 Centers for Disease Control and Prevention; and National Institute for Occupational Safety and Health. Environmental Control for Tuberculosis: Basic Upper-Room Ultraviolet Germicidal Irradiation Guidelines for Healthcare Settings. Washington, DC: Department of Health and Human Services; 2009.