A human being can globally be considered as a whole set of electric processes in interaction with biochemical mechanisms. Furthermore, one is opened to one's environment and always interacts with it. By means of interactions with our electric and biochemical processes, the electromagnetic fields can interact, for the better or the worst, with our health.

We mainly refer to radio frequencies and hyper frequencies. These kinds of fields generate an absorption of energy entailing thermal effects by rise of the temperature of tissues. The energy accumulation is measured by the flow of specific absorption or DAS .

The DAS (whole or part of the body) strongly depends on the distance between the origin of the energy and the body. For a few devices, especially mobile phones, the exposure of the human body can take place in "close field". The origin of the energy is in touch with a part of the body. The exposure in "close field" can entail a high local DAS .

Studies revealed an increase of 2°C of the temperature of the brain only after 3 minutes of communication. In practice, the value of the DAS is assessed from the parameters of the incidental field (frequency , intensity, polarization, close or distant field), from the characteristics of the exposed body (size, geometry, position with regard to the incidental field, dielectric properties of the tissues) – that’s why it’s difficult to extrapolate to a man the results of the animal experiments, the effects of the ground and the other reflective objects near the exposed body.

Although there aren’t any confirmed studies, we can suppose that computer screens , of course at a short distance, expose the user to comparable electromagnetic fields, even higher than the ones emitted by mobile phones.

The indirect interactions or currents of contact result from the contact of the body with an object being in a different electric potential, whether it is the body or the object which is loaded by the electromagnetic field. They depend on the frequency of the field, on the dimension of the object, on the size of the subject and on the contact area.

Discharges can even occur when a person and a conductive object exposed to an intense field get closer.
Fields can interact with a medical device carried or implanted in the body and disrupt its functioning.