AAQ Malaysia offers commercial and residential UV light air purifiers. The Airsopure product line users a specific 253.7 nm wavelength UV-C lamp to ensure a maximal germicidal effect without generating any negative by-products like Ozone.
UV-A is the least harmful and most commonly found type of UV light, because it has the least energy. UV-A light is often called black light, and is used for its relative harmlessness and its ability to cause fluorescent materials to emit visible light – thus appearing to glow in the dark. Most phototherapy and tanning booths use UV-A lamps.
UV-B is typically the most destructive from of UV light, because it has enough energy to damage biologic tissues, yet not quite enough to be completely absorbed by the atmosphere. UV-B is known to cause skin cancer. Since most of the extraterrestrial UV-B light is blocked by the atmosphere, a small change in the ozone layer could dramatically increase the danger of skin cancer.
Short wavelength UV-C is almost completely absorbed in air within a few hundred meters. When UV-C photons collide with oxygen atoms, the energy exchange causes the formation of ozone. UV-C is almost never observed in nature, since it is absorbed so quickly. Germicidal UV-C lamps are often used to purify air and water, because of their ability to kill bacteria.