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EXPOSURE TO EXTREMELY LOW FREQUENCY ELECTROMAGNETIC FIELDS DURING LESSONS IN SECONDARY SCHOOLS
Wasana Silangam1, Witaya Yoosook1, Pornpimol Kongtip1
1Department of Occupational Health and Safety, Faculty of Public Health, Mahidol University, Bangkok, Thailand.
Abstract:
Schools are a significant location where children are exposed to electromagnetic fields (EMFs), which may cause adverse health effects. This cross-sectional study aimed to examine exposure levels to extremely low frequency magnetic fields (ELF-MFs) with a range of 5 Hz-32 kHz, and ELF-electric fields (ELF-EFs) with a range of 5 Hz-2 kHz in secondary schools in Bangkok, Thailand. This study was conducted in 60 classrooms from three schools during class hours. Spot measurements were taken with a Narda EFA 300 field analyzer to evaluate exposure levels. This study showed that ELF-EMF exposure levels are lower than ICNIRP guidelines, while 21.67% of classrooms had a magnetic field strength above 0.2 μT, and the main sources of ELF-EMFs were electrical equipment and electrical wiring. Future studies should measure ELF-EMF levels in other areas and evaluate the effects of long term exposure to ELF-EMFs on children's health.
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