{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,10]],"date-time":"2026-10-10T16:03:00Z","timestamp":1791648180352,"version":"4.3.4"},"reference-count":56,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2023,2,1]],"date-time":"2023-02-01T00:00:00Z","timestamp":1675209600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003565","name":"Ministry of Land, Infrastructure and Transport","doi-asserted-by":"publisher","award":["225MIP-A156381-03"],"award-info":[{"award-number":["225MIP-A156381-03"]}],"id":[{"id":"10.13039\/501100003565","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003565","name":"Ministry of Land, Infrastructure and Transport","doi-asserted-by":"publisher","award":["2016R1A6A1A03012812"],"award-info":[{"award-number":["2016R1A6A1A03012812"]}],"id":[{"id":"10.13039\/501100003565","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003725","name":"National Research Foundation of Korea","doi-asserted-by":"publisher","award":["225MIP-A156381-03"],"award-info":[{"award-number":["225MIP-A156381-03"]}],"id":[{"id":"10.13039\/501100003725","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003725","name":"National Research Foundation of Korea","doi-asserted-by":"publisher","award":["2016R1A6A1A03012812"],"award-info":[{"award-number":["2016R1A6A1A03012812"]}],"id":[{"id":"10.13039\/501100003725","id-type":"DOI","asserted-by":"publisher"}]},{"name":"the Basic Science Research Program through the National Research Foundation of Korea (NRF)","award":["225MIP-A156381-03"],"award-info":[{"award-number":["225MIP-A156381-03"]}]},{"name":"the Basic Science Research Program through the National Research Foundation of Korea (NRF)","award":["2016R1A6A1A03012812"],"award-info":[{"award-number":["2016R1A6A1A03012812"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Occupational health and safety hazards associated with confined places are mainly caused by exposure to toxic gases and oxygen deficiency. Lack of awareness, inappropriate monitoring, and improper evacuation methods can lead to worker fatalities. Although previous studies have attempted to develop systems to solve this issue, limited research is available on their application in confined places. In this study, a real-time helmet-mounted system was developed to monitor major toxic gases (methane (CH4), hydrogen sulfide (H2S), ammonia (NH3), and carbon monoxide (CO)), oxygen, temperature, and humidity. Workers outside and inside confined spaces receive alerts every second to immediately initiate the rescue operation in the event of a hazard. The test results of a confined environment (wastewater treatment unit) highlighted that concentrations of CH4 and H2S were predominant (13 ppm). Compared to normal atmosphere, CH4 concentration was 122- and 130-fold higher in the landfill and digestion tanks, respectively, while H2S was 36- and 19-fold higher in the primary and secondary clarifiers, respectively. The oxygen content (18.2%) and humidity (33%) were below the minimum required limits. This study will benefit future research to target appropriate toxic gas monitoring and alert workers by studying the existing issues and associated factors in confined places.<\/jats:p>","DOI":"10.3390\/s23031590","type":"journal-article","created":{"date-parts":[[2023,2,1]],"date-time":"2023-02-01T05:04:48Z","timestamp":1675227888000},"page":"1590","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":33,"title":["Helmet-Mounted Real-Time Toxic Gas Monitoring and Prevention System for Workers in Confined Places"],"prefix":"10.3390","volume":"23","author":[{"given":"Janani Priyanka Perumpally","family":"Rajakumar","sequence":"first","affiliation":[{"name":"ICT Integrated Safety Ocean Smart Cities Engineering Department, Dong-A University, S12-401, 550 Bungil 37, Nakdong-Daero, Saha-Gu, Busan 49315, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1270-6310","authenticated-orcid":false,"given":"Jae-ho","family":"Choi","sequence":"additional","affiliation":[{"name":"ICT Integrated Safety Ocean Smart Cities Engineering Department, Dong-A University, S12-401, 550 Bungil 37, Nakdong-Daero, Saha-Gu, Busan 49315, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,2,1]]},"reference":[{"key":"ref_1","unstructured":"(2023, January 20). 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