Emissions from the Sun include visible light, heat and ultraviolet (UV) radiation. Just as
visible light consists of different colours that become apparent in a rainbow, the UV
radiation spectrum is divided into three regions called UV-A, UV-B and UV-C. Among
these, UV-C is found to be the most effective disinfectant against most microorganisms. It
is the spectrum of electromagnetic radiation between 200nm to 280 nm.