The magnetic field right next to the Cefaly is below 0,2µT (i.e. 2mG). This value is negligible compared to the field generated by an electric shaver (typically between 15 and 1500µT when measured at 3cm) or by an hair dryer (typically between 6 and 2000µT).
Neurostimulation has been used for more than 20 years with devices that are implanted in the head and which work constantly for several years. The only problems encountered with implantable neurostimulators relate to the surgical procedure involved to implant them, and never to the neurostimulation technique itself. This is why this technique is regarded as exceptionally safe. Cefaly’s great breakthrough is to allow this technique of neurostimulation to be used in an external and gentle manner.