Radiation protection limit values come from the “Guidelines for limiting exposure to time-varying electric, magnetic, and electromagnetic fields (up to 300 GHz)”, published by the ICNIRP in 1998. They are based on the thermal effect (the warming of body tissue). For instance, body temperature can rise when electromagnetic radiation is absorbed by the body and converted into heat energy. Valid limits depend on the radiation intensity that warms an inanimate body by 1°C within 30 minutes. It is because natural mechanisms that regulate this can’t function properly beyond this temperature. Mobile phones, for example, mustn’t exceed a value of two watts per kilogram (SAR values); otherwise a thermal effect sets in. As long as the limits are followed, there is no health risk, according to the ICNIRP. This, however, doesn’t take into account long-term effects and the much greater physiological sensitivity of a child’s head. More importantly, the ICNIRP guidelines which have been in existence for 20 years have not been updated to meet the ever-changing technology.