T he magnetic field produced by electrical wiring, electrical systems and other equipments connected to the production, transmission, distribution and use of electricity, is called alternate magnetic field since it is the product of alternate current (such as domestic current) that varies sinusoidally over time.
The frequency of a magnetic field specifies the number of oscillations per second and the unit used to measure it is Hertz (Hz).
A low frequency magnetic field ranges between 0 Hz and 100 kHz.
On the other hand, an extremely low frequency (E.L.F.) magnetic field ranges between 0 Hz and 10 kHz.