SAR stands for Specific Absorption Rate and is used by the FCC to measure radio frequency absorption by the body from cell phones.
According to the FCC, “SAR provides a straightforward means for measuring the RF exposure characteristics of cell phones to ensure that they are within the safety guidelines set by the FCC.”
Researchers place the phone against a model of the human head to measure the Specific Absorption Rate of a cell phone. The idea is to put it in a realistic “talk position” that mimics how a real user would interact with the phone. Then, they take the measurement at the location where there is the highest absorption rate. Oftentimes, this is when the head is as close to the phone’s internal antenna as possible.
The FCC’s limit for public exposure to this type of radiofrequency is 1.6 watts per kilogram. Due to Samsung’s innovative antenna system, their mobile phones tend to have the lowest SAR levels; the Samsung Galaxy S10e, for example, has a SAR level of only 0.34 W/kg. Brands like Alcatel, Huawei, and Apple produce phones with higher SAR levels. The Huawei Ascend Mate 7 has a rating of 1.54.