{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,5]],"date-time":"2026-10-05T08:57:35Z","timestamp":1791190655602,"version":"4.1.0"},"reference-count":31,"publisher":"MDPI AG","issue":"15","license":[{"start":{"date-parts":[[2020,7,22]],"date-time":"2020-07-22T00:00:00Z","timestamp":1595376000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"the National Research Foundation of Korea (NRF) funded by the Ministry of Education","award":["2018R1D1A1B07051103"],"award-info":[{"award-number":["2018R1D1A1B07051103"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJERPH"],"abstract":"<jats:p>Schools are an important place for children\u2019s exposure to electromagnetic fields, which may cause adverse health effects. To better understand environmental extremely low-frequency magnetic fields (ELF-MFs) exposure among elementary school students, we measured numeric values of ELF-MFs in five classrooms at four schools during digital learning class hours. The measurement of ELF-MFs was taken with an EMDEX II field analyzer. Specifically, we examined the level of exposure to ELF-MFs for each student\u2019s seating position in the classroom. The results showed that ELF-MFs exposure levels were lower than those in the International Commission on Non-Ionizing Radiation Protection guidelines; however, there were significant differences in the level of magnetic field exposure at each school and at each student\u2019s seat. The exposure to ELF-MFs at students\u2019 seat positions was mostly caused by electrical appliances, electronic wiring, and distribution boxes, but the exposure level decreased as the distance increased. Therefore, it is important to design safe and appropriate environments for digital learning in schools, such as proper seating arrangements, to avoid ELF-MFs exposure to students as much as possible. Future studies should measure ELF-MFs levels in other areas and investigate the effects of exposure to ELF-MFs during school hours on children\u2019s health.<\/jats:p>","DOI":"10.3390\/ijerph17155284","type":"journal-article","created":{"date-parts":[[2020,7,23]],"date-time":"2020-07-23T10:14:06Z","timestamp":1595499246000},"page":"5284","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":12,"title":["Extremely Low-Frequency Magnetic Fields Exposure Measurement during Lessons in Elementary Schools"],"prefix":"10.3390","volume":"17","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-8538-0476","authenticated-orcid":false,"given":"JinKyung","family":"Park","sequence":"first","affiliation":[{"name":"College of Nursing, Korea University, Seoul 02841, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2510-9112","authenticated-orcid":false,"given":"EunHye","family":"Jeong","sequence":"additional","affiliation":[{"name":"College of Nursing, Korea University, Seoul 02841, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"GyeongAe","family":"Seomun","sequence":"additional","affiliation":[{"name":"College of Nursing, Korea University, Seoul 02841, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2020,7,22]]},"reference":[{"key":"ref_1","unstructured":"World Health Organization (2007). 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