طب کار (Apr 2017)
Measurement of train’s driver occupational exposure to static magnetic field
Abstract
Introduction: One of the pollutants that is developing in human life day by day is Magnetic field. In modern urban transport systems, diesel motors have been replaced with electric motors, working with alternating and direct currents, and leading to occupational exposure of drivers with magnetic fields. This study aimed to determine the urban trainchr('39')s drivers exposure with static magnetic fields and compare it with national occupational exposure limits. Methods: In order to measure the trainchr('39')s drivers exposured with static magnetic field, several samples were selected from urban AC and DC and AC intercity trains, in the 1,2,4, and 5 lines of Tehran, Iran. After determination of the sampling location, static magnetic field was measured by three axes magnetic field meter (HI-3550), according to the standard IEEE std C95.3.1 and previous studies. In order to analyze the data, SPSS software (ver. 20) was used. Results: The maximum exposure of drivers was in DC trains- line 2- (0.52 mT), meanwhile, average exposure of AC trains driver (0.095 mT) was higher than DC trains driver (0.081 mT). The average magnetic flux density between different lines has not have significant differences. The highest levels of time-weighted average exposure were related to line 1 AC train drivers (0.06 mT). Conclusion: Exposure of train’s drivers was 10 time higher than background level, indicating a significant exposure in this job. However, in none of the assessment situation, the whole body exposure of train’s drivers was not exceeded from National Occupational Exposure Level (TWA= 0.2 and ceiling= 2 T). Of course, it does not imply that this level of exposure is completely safe, because different studies have reported health problems even at lower values of the magnetic field.
