Comparison of safety distances based on the electromagnetic field and based on the SAR for occupational exposure of a 900-MHz base station antenna

A comparison between the safety distances of a base station antenna using electromagnetic field and the specific absorption rate (SAR) assessment is made. The input power in the antenna is determined such that the electromagnetic fields and the SAR equal the reference levels and the basic restrictions, respectively, at a certain distance. Up to about 10 W the localized SAR delivers the largest safety distances when the electric field averaged in a volume is considered. This means that from 10 W and up the SAR does not need to be determined to obtain the largest safety distances. Safety distances based on the SAR will be smaller than those obtained from the electromagnetic fields when the maximum field value in a plane is considered.