The function of UV filters are to destroy many harmful particles for our lungs. Many microorganisms which are normally found in the air and which we are unable to see with the naked eye are eliminated.
Remember that UV is just an acronym that stands for Ultra Violet.
Consequently, the UV purifier is a purifier that emits radiation in the Ultraviolet spectrum.
The figure shows the spectrum of light, including UV radiations. These are invisible to the human eye, which only perceives rays in a certain wave range (400 to 780nM).

UV rays are invisible to the human eye and have the property of being shorter in wavelength than visible light (100 to 400 nM).
UV rays are divided into:
UV-A: these ultraviolet rays are best known because they cause the most damage to the skin.
UV-B: these are the rays that give the skin the so-called tan, the healthy tanned complexion we all aspire to in the summer months.
UV-C: these rays are harmless to humans, but harmful to most microorganisms and viruses in the air and cause allergies and breathing disorders. UV-C destroys the DNA and RNA of microorganisms, leaving them harmless to human health. This is why they are also called UVGI rays or germicidal violet radiation.

UV radiation, emitted by the sun, if properly dosed in intensity and wavelength, can be used in many applications in our daily lives.
When applied to LED lamps, UV technology can be very useful in various sectors, and is used differently depending on intensity and wavelength (UV-A, UV-B, UV-C). In particular, it can be very effective in reducing the amount of bacteria, the virulence of harmful organisms and the presence of pathogens, as well as in the breakdown of volatile organic compounds (VOC), thus reducing odours in general.