UV light is as diverse as the various colors of the visible spectrum. Yet, when we think about UV light, we tend to forget this, and just categorize it as a range of wavelength associated with its usefulness in fluorescence, curing or disinfection effects. Frankly, it is every important to distinguish between various types of UV energy, as each type has very different properties.
UV energy should first and foremost be verified by the wavelength. The wavelength can determines the type of UV light energy. UV-A ranges from 315NM to 400NM, while UV-C includes wavelength from 100-280NM. UV-B is 280 to 351NM.
UV lights are not visible to human eye. So you can not visually see the difference between these types of UV. However some light sources can be visually distinguished, like, red or blue light. So it is more important that you know the detailed light source for your particular application.
Most UV-A lamps are used either fluorescence or curing application, with a wavelength of 365NM. Fluorescence is a phenomenon where material or minerals convert UV-A energy to a visible wavelength. UV lamps that are used for fluorescence application are called blacklights, as the lights appear dark, but upon shining them on various objects, they emit various visible colors.
The most common wavelength for UV-A fluorescence are 365NM and 395NM. Generally, both 365 and 395NM can create fluorescence effects, but 365NM will provide a cleaner UV effect with less visible light output, while 395NM will have a small visible a small visible violet component.
Unlike the UV-A, UV-C occupy a much lower wavelength range of 100NM to 280NM. UV-C is always used as an effective way to deal with viruses, bacteria and molds. UV-C is an effective germicidal wavelength. UV-C is unique in its ability to perform germicidal function because of the wavelength susceptibility of virus.
Different wavelength can be used for different application. In the industrial application, the UV-A is mainly used for NDT, Lab/lifescience, forensics, UV curing and so on. UV-C due to its features, it is mainly used in the medical application. When we learn more about the UV, we can seek more applications build widely usage for the UV light.