The influence of children's weight on the absorption of electromagnetic fields

Higher specific absorption rate (SAR) values have been found in children when exposed to RF sources. It is worth noting that mass densities of each of the tissues is always used as of that of an adult person, despite the evident difference of tissue dielectric values due to the difference of water contents in each development stage. Some researchers have reported that children may exhibit higher SAR values than the guideline levels in certain exposure conditions. Therefore, this study is conducted to find out the reason why it is the case. Numerical assessment in two child models, namely Eartha and NORMAN, has been performed when exposing to a plane wave of vertical polarization from front to back. The comparison with the muscle equivalent models has revealed that the low body weight in child models results in relatively high SAR. It is shown that around 35-40% increase in the body weight in the heterogeneous models would reduce the whole body averaged SAR values approximately by 30% and 16-19 % at 900MHz and 1900MHz, respectively.