For some people, the SAR (Specific Absorption Rate) value of a mobile phone is quite a big deal. It measures the amount of radio frequency (RF) energy absorbed by the body when using the handset. The figure is measured in Watts per kilogram (W/kg) and the higher the value the more radiation is absorbed.
Each country has a maximum limit, for example in the United States the maximum SAR value is 1.6 W/kg, whilst in Europe it is 2.0 W/kg. These levels can differ depending on how each entity tests it, but thankfully Sony Xperia Z owners will not have to worry about it. Sony Mobile France confirmed that the SAR value for the Xperia Z is 0.55 watts per kilogram. Of course, if you are worried about these risks, always take precautions such as using a hands-free option.
Pour mettre fin aux rumeurs, le DAS du Xperia Z est bien de 0.55 W/Kg.
— Sony Xperia FR (@SonyXperiaFR) February 4, 2013