to find the minimum distance the federal government recommends that your cell phone must be away from your body. Keeping it closer than the designated distance can result in a violation of the FCC Exposure Limit. Exceeding FCC levels is proven to result in burns, sterility and brain damage. Learn more about fine print instructions and see all the FCC warnings here.
The energy of electromagnetic radiation is determined by its frequency; ionizing radiation is high frequency, and therefore high energy, whereas non-ionizing radiation is low frequency, and therefore low energy. The NCI fact sheet Electromagnetic Fields and Cancer lists sources of radiofrequency radiation. More information about ionizing radiation can be found on the Radiation page.