Frequency Selective EMF Measurements and Exposure Assessment in Indoor Office Environments

The results of an extensive radio-frequency electromagnetic field (RF-EMF) measurement campaign in indoor office locations are presented. Frequency selective EMF recordings have been carried out in different corporate buildings between 75 and 3000 MHz. Exposure levels for the general public are extracted, assessed and compared with the national and international limits. The results from the entire building dataset reveal that the total electric field varies between 0.29 and 0.75 V/m (0.24-1.90 mW/m
²
in terms of total power density), whereas the mean Total Exposure Ratio (TER) is on the order of $(3.35 \pm 1.41)\cdot 10^{-4}$. In all cases the exposure levels in indoor environments abide by the legislated limits. Furthermore, the exposure values are found to be strongly related with the floor level, increasing linearly. This tendency is attributed to the diffraction and penetration propagation mechanisms. Finally, broadcast and cellular emissions account for more than 57% of the total radiated levels, especially at higher floors, where they reach up to 80%.