Analysis of critical situations in the evaluation of human exposure to magnetic fields with complex waveforms.

The paper analyses some critical situations in the assessment of the compliance with the human exposure limits to the low-frequency magnetic fields. The study is focused on non-sinusoidal and transient waveforms in the frequency range from 8 Hz to 65 kHz. It is carried out by combining measurements and numerical evaluations, starting from actual magnetic flux density behaviours. The results show that inconsistent indications of compliance with the exposure limits may arise not only because of the evaluation method adopted, but also as a result of the used time or frequency windows in relation to the investigated magnetic field waveform.