Evaluation of extremely low-frequency magnetic field (ELF) at Tehran City in 2012

The power transmission lines are the emission source of extremely low frequency (ELF) electromagnetic fields that are considered to have an adverse impact on human health. Therefore the aim of this study was to evaluate the amount of magnetic flux with extremely low frequencies (ELF) around high voltage power transmission lines in the western areas of Tehran in 2012. In this study the magnetic flux density was measured around three lines of high voltage electricity transmission (63، 230 and 400 kV). The employed device for magnetic flux measurement was Triple axis TES 1394 tester. The measurements were taken according to IEEE standard procedures (Std 644-1994) in four distance (0، 5، 10 and 20 m). The results showed that the amount of the minimum، mean and maximum of magnetic flux density were 0. 14،1. 43 ±1. 25 and 11. 51µT respectively. The flux density was lower than the standard international commission on ionizing radiation protection in all cases. Discussion and The average level of magnetic flux density was about 1. 25% of the exposure limit ICNIRP standard (100 µT) around the three lines. Also the magnetic flux density rate decreases with increasing distance from the line and decreasing flow.