Whether, and if so how dangerous, the radiation from a smartphone actually is when making a call has not yet been conclusively clarified. As a precautionary measure, however, there are limit values that manufacturers must adhere to. Because one thing is certain: mobile communications use high-frequency electromagnetic fields, some of the energy of which is absorbed by the head when making a call.
This is called the specific absorption rate (SAR), which is measured in watts per kilogram. The limit for smartphones is 2 watts per kilogram.
The value is set very high for modern smartphones, and there is no smartphone in the entire CHIP test environment that reaches this limit, even if some smartphones come very close to this SAR value. The Motorola Edge, for example, is 1.79 W/kg, the ZTE Axon 11 5G is 1.60 W/kg and the Google Pixel 4a is still 1.37 W/kg.
No smartphone is critical, so there is no need to worry. However, if you use your smartphone to make a lot of calls and want to be absolutely sure that you are getting as little radiation as possible, you will find 15 tested smartphones from the CHIP best list with the lowest SAR values in the following list.