Electromagnetic radiation in the frequency range 300-2450 MHz.
Non-ionising electro-magnetic radiations in the frequency range of 30—300,000 megahertz. They are emitted from electronic devices, such as heaters, some domestic ovens, television receivers, radar units and diathermy units. Those using them industrially are advised to protect their eyes, as there is some evidence that prolonged exposure may induce cataract.
That portion of the radio wave spectrum between a wavelength of 1 mm and 30 cm.