|
Recently, there are many reports about potential healthhazards affected by low frequency electromagnetic fields (LF-EMF) emitted (or radiated) from the AC 60Hz power line and the monitors (LF includes ELF and VLF). Health hazards by LF-EMF are called "LF-EMF Biological Effects". Many EMF standards have been established. Therefore, most of these standards list only electric field intensity(E) and magnetic flux density (B) but ignore factors such as time-domain waveforms and frequency-spectrums of EMF.The monitors emit repetitious pulse EMF (RP-EMF). In the thesis we discuss the devices including fluorescent lamps, monitors, TVs, the switching power supply, and the coil for generating pure sine wave. Then we observe the effects of the sprout rate, the growing speed, and the growing length probability distribution of the plants exposed in EMF emitted from these devices. By Using LF spectrum analyzer and oscilloscope, we analyze RP-EMF spectrums and compare with the background spectrum. Finally, we can get the rising level of the magnitude of EMF in different frequency bands and compare with the growing results of the plants to verify that repetitious pulse EMF could be more harmful than non-pulse EMF.
|