The feeling for this subject was stimulated by the intensive use of mobile phones and the presence of powerful radio and television transmitters. It was realized, however, that sources of electromagnetic fields are many and recently has realized that it's not just the radio transmitters that emit potentially harmful fields for people.
The verification of conformity with the requirements of human exposure is now conducted by applying different methods depending on the characteristics of the source of electromagnetic field and its position than people. To be carried out properly it requires knowledgeable and experienced staff in this field.
There are then specific assessment methods for equipment used near your ear like mobile phones, those close to the body including laptops, and those found on a table or on the wall or on the floor such as WiFi routers and appliances.
All mobile devices that are used in the proximity of the head or body in order to be placed on the market must be tested to demonstrate their conformity with these SAR standards. The SAR is defined as the amount of EM energy absorbed by the human body per unit mass and is measured in W/Kg.