UVGI or otherwise known as Ultraviolet germicidal irradiation is a method that uses UV-C (short-wavelength ultraviolet) light to inactivate or kill microorganisms. This method disrupts their DNA by destroying the nucleic acids. It renders them unable to manage cellular functions. 

A microorganism is a single-celled animal that is a mediator for infectious diseases. In the 19th century, the influence that UV light purification has on these creatures was discovered by scientists. 

Hospitals have been using UVGI to inactivate TB for quite some time. Recent studies have been done by the National Institute for Occupational Safety and Health to create even better ways to render TB inactive in more than just hospital settings. Places such as homeless shelters, prisons, and more will likely be seeing an increase in help from UV light purification. TB can remain in the air for a long period of time due to how light it is. Because this microorganism is so easily airborne, the use of the UVGI has dramatically reduced the risks in medical facilities. The CDC and the NIOSH are, even now, formulating ideas for even better UV lights and systems for the health of everyone. 

Historical Facts 

It was as early as 1845 when it was discovered that microorganisms responded to light. In 1877, Blunt and Downes exposed test tubes to sunlight that contained Pasteur's solution. When they did this, they realized that the sunlight prevented the growth of the microorganisms. This was the accidental discovery of UVGI. Upon realization that the sunlight could prevent the growth of these organisms, Blunt and Downes then proceeded to record exposure times with other microorganisms by increasing and decreasing exposure times with each one. They then discovered that with increased exposure time, the test tubes remained free of bacteria for up to several months. After this discovery, the two went a step further and began to demonstrate how sunlight can neutralize bacteria depending on the duration, wavelength and intensity of the exposure. They went on to show that the shorter wavelength of the solar spectrum was the most effective in the deactivation of bacteria. That is to say, they studied the wavelengths of UV light purification to determine what forms of UV light would be needed to destroy specific microorganisms. The two scientists are considered to have had the most influence in the process of photo-biology. 

The early experiments lead to more in-depth studies. The inactivation of certain organisms depends on the dose of the radiation that the organism receives. The inactivation of the organisms also depends upon the wavelength of the radiation. This began the devoted investigation to find the wavelengths needed for specific inactivation of targeted bacteria. From these initial findings, other scientists began their own research into this field. It is conclusive that UVGI is an effective disinfection method and has been used for this purpose for decades.

Material from Vida Shield