Often referred to as ultraviolet (UV) light, UV radiation is a type of electromagnetic radiation naturally generated by the sun with a higher frequency and lower wavelength than visible light. UV radiation comes naturally from the sun, but it can also be created by artificial sources.
Ultraviolet radiation comes naturally from the sun. While UVA and UVB wavelengths are able to reach the Earth, UVC rays are completely stopped by the atmosphere.
Considered a natural disinfectant, UV light is divided into three bands. UVC, which is UV light with the shortest wavelength is fully absorbed by the Earth’s atmosphere and does normally not reach the Earth’s surface. A great part of UVB radiation is also absorbed. The UV radiation reaching the Earth’s surface is largely composed of UVA with a small UVB component. Perhaps you recognize the terms UVA and UVB from the sunscreen lotion you can buy.
UVC light effectively destroys all kinds of germs.
UV radiation has effectively been used for decades to reduce the spread of bacteria, such as tuberculosis. UVC light is the most effective of all germicidal light. It kills germs by damaging their DNA. If the DNA sequence is not correct, the microorganism cannot reproduce and multiply. UVC light destroys all microorganisms, including drug resistant bacteria.
Just like the sunbeam, UV disinfection works by line of sight, meaning any area the light doesn’t reach will not be disinfected. In addition, UV light cannot pass through glass or plastic. Dirt or grease on the surface of an object can also reduce the effectiveness of UV radiation.
The terms “disinfection” and “sterilization” are sometimes, and unfortunately, used interchangeably. However, they mean different things. Sterilization is an extreme physical or chemical process that eliminates all forms of microbial life, including all bacterial spores. Hospitals use sterilization on surgical tools. Disinfection reduces the number of microbes so that is no longer harmful, but some bacterial spores remain. Thus, UV radiation does not provide sterilization. Have this in mind when seeing UVC products claiming to sterilize. It is simply not true.
Historically, mercury lamps have been the only option for disinfection. A more recent technology is UVC LEDs. UVC LEDs are relatively long lived and don’t contain any toxic materials, but they are less efficient than mercury lamps. Most of the energy created by LEDs is turned into heat, which needs to be transported away. Otherwise, as the LED light warms up, its light output decreases.
PureFize® is a unique UVC technology based on field emission, which in many ways is similar to how an old TV works, only in a nano environment. Field emission is release of electrons from the surface of a material due to the presence of an electric field. The electrons strike the inside of a lamp glass coated with light powder and a very thin conductive layer, creating light. The properties of the light, such as wavelength, are controlled by the light powder. PureFize minimizes the heating that often occurs in other technologies when increasing power to compensate for poor energy efficiency.
Here’s where you can find PureFize.
For more information about UV radiation and PureFize, see our section with frequently asked questions.