But according to the FCC, comparing SAR values between phones can be misleading. The listed SAR value is based only on the phone operating at its highest power, not on what users would typically be exposed to with normal phone use. The actual SAR value during use varies based on a number of factors, so it’s possible that a phone with a lower listed SAR value might actually expose a person to more RF energy than one with a higher listed SAR value in some cases.
Many respected scientists join them. “We found no evidence of an increased risk of brain tumors or any other form of cancer” from cell-phone radiation, says John Boice Jr., Sc.D., president of the National Council on Radiation Protection & Measurements and a professor of medicine at the Vanderbilt University School of Medicine in Nashville, Tenn. “The worry should instead be in talking or texting with your cell phone while driving.”
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.