Measurement of magnetic fields radiated by 31.5 kV underground transmission line and exposure assessment

The need for electrical energy is increasing day by day with the increasing population, developing industry and technology. Due to this increasing need, the safe and uninterrupted transmission and distribution of the generated energy is just as important as generation of electrical energy. Especially in areas where residential areas are dense, underground energy cables are used to ensure that the transmission and distribution of energy is safer than overhead lines and aesthetically. Underground energy cables, like other transmission and distribution elements, create electromagnetic fields around them. Electromagnetic fields that living things are exposed increase with the increasing need for energy, and together with this, the possible negative effects of electromagnetic fields on living things come to the fore. Necessary precautions should be taken to ensure that the exposed electromagnetic fields do not exceed the limit values. In this study; Electromagnetic fields created by underground energy cables used in electricity transmission and distribution have been examined, and the literature on the effects of electromagnetic fields on health has been reviewed. International standards regarding exposure to electromagnetic fields and the legislation in force in Turkey were researched and comparisons were made. The site where the high voltage three-phase underground power cable is located, where electricity is distributed, was selected for an exemplary exposure assessment. Magnetic flux densities were measured by broadband and frequency selective methods, covering the 45-2000 Hz frequency band, in the center of the power transmission line and its immediate surroundings. The measurements were even repeated at different horizontal distances and at different heights. Considering all the measurement results, it was observed that the field level was 2.89 µT and below. According to the limit values determined by ICNIRP, the highest exposure rate was determined as 2.31% and the results were obtained below the limits. When the 0.2 µT level, which was determined as risky in some epidemiological studies, is taken as reference, it was concluded that this level was exceeded at many measurement points.