UV itself can be subdivided into near UV (380-200 nm wavelength) and extreme or vacuum UV (200-10 nm). When considering the effects of UV radiation on human health and the environment, the range of UV wavelengths is often subdivided into UV-A (380-315 nm) [also called Long Wave or "blacklight"], UV-B (315-280 nm) [also called Medium Wave], and UV-C (280-10 nm) [also called Short Wave or "germicidal"]. Unshielded exposure of the skin or eyes to mercury arc lamps that do not have a conversion phosphor is quite dangerous.
   The offered phosphors convert the ultraviolet radiation of mercury discharge of UV-C range (253,7 nm) into longer wavelength range UV-A. Such converted UV-light is applicable in medicine for phototherapy of skin diseases (in particular, psoriasis), in cosmetics for artificial sunburn, in photocopy equipments, for photopolymerization, UV-hardening, metal defectoscopy, for cheking up banknotes, for creating decorative-advertising effects in illumination and many other purposes.