Assessment of the environmental electromagnetic field by time series of continuous measurements

Continuous measurements of the electromagnetic field strength reveal variations that are not observed in the 6' average period stipulated in CENELEC ENV 50166-2. Several examples are presented here of prolonged measurements at different places and conditions, using a wide band E field meter. Taking each record as a time series, its power spectra were analyzed by means of wavelets. This showed the existence of several cycles, mainly of 24 hours. These oscillations shows that people are normally exposed to a low level field of amplitude modulated by an extremely low frequency, of which the effects are unknown