It has been known since 1920 that Ultra-Violet Light (UVc) in the “C” spectrum (220 to 280 nanometers) has a germicidal effect on all micro-organisms including moulds and bacteria. The germicidal effect of UVc works by deactivating the DNA of the organism which stops it from multiplying. UVc has been used in many applications since 1920, such as water purification