The spectrum of the electromagnetic radiation covers very wide frequency range from static fields up to the gama rays. Because of so different frequencies interaction with human and possible health risks are different. Human body interacts very different already when exposed to static or low frequency fields and electromagnetic fields emitted by the mobile phones (900 MHz - 2100 MHz).

Electromagnetic fields, which do not have enough energy to ionize the atoms or molecuels, are called non-ionizing radiation. In the frequency range of non-ionizing radiation, static electric and magnetic fields belong as well as RF (Radio Frequency), MIcrowave, Teraherz, Infrared, Visible and Ultraviolet radiation. Electromagnetic fields with higher frequencies are able to ionize the atoms or molecules.