{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,18]],"date-time":"2026-08-18T04:45:26Z","timestamp":1787028326277,"version":"build-2736575974"},"reference-count":64,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2021,5,4]],"date-time":"2021-05-04T00:00:00Z","timestamp":1620086400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"European Regional Development Fund","award":["T-3036, 2013"],"award-info":[{"award-number":["T-3036, 2013"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJERPH"],"abstract":"<jats:p>Aimed at preventing heat strain, health problems, and absenteeism among workers with physically demanding occupations, a continuous, accurate, non-invasive measuring system may help such workers monitor their body (core) temperature. The aim of this study is to evaluate the accuracy and explore the usability of the wearable non-invasive Cosinuss\u00b0 \u00b0Temp thermometer. Ear canal temperature was monitored in 49 workers in real-life working conditions. After individual correction, the results of the laboratory and field study revealed high correlations compared to ear canal infrared thermometry for hospital use. After performance of the real-life working tasks, this correlation was found to be moderate. It was also observed that the ambient environmental outdoor conditions and personal protective clothing influenced the accuracy and resulted in unrealistic ear canal temperature outliers. It was found that the Cosinuss\u00b0 \u00b0Temp thermometer did not result in significant interference during work. Therefore, it was concluded that, without a correction factor, the Cosinuss\u00b0 \u00b0Temp thermometer is inaccurate. Nevertheless, with a correction factor, the reliability of this wearable ear canal thermometer was confirmed at rest, but not in outdoor working conditions or while wearing a helmet or hearing protection equipment.<\/jats:p>","DOI":"10.3390\/ijerph18094896","type":"journal-article","created":{"date-parts":[[2021,5,5]],"date-time":"2021-05-05T11:06:01Z","timestamp":1620212761000},"page":"4896","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":20,"title":["Evaluation of a Wearable Non-Invasive Thermometer for Monitoring Ear Canal Temperature during Physically Demanding (Outdoor) Work"],"prefix":"10.3390","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6489-6967","authenticated-orcid":false,"given":"Charlotte Christina","family":"Roossien","sequence":"first","affiliation":[{"name":"Department of Rehabilitation, University of Groningen, University Medical Center Groningen, Medicine, 9713 GZ Groningen, The Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Audy Paul","family":"Hodselmans","sequence":"additional","affiliation":[{"name":"Center for Applied Research and Innovation in Health Care and in Nursing, Hanze University of Applied Sciences, 9747 AS Groningen, The Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ronald","family":"Heus","sequence":"additional","affiliation":[{"name":"Institute for Safety (IFV), Knowledge Center Occupational Safety, 6816 RW Arnhem, The Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Michiel Felix","family":"Reneman","sequence":"additional","affiliation":[{"name":"Department of Rehabilitation, University of Groningen, University Medical Center Groningen, Medicine, 9713 GZ Groningen, The Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3533-2446","authenticated-orcid":false,"given":"Gijsbertus Jacob","family":"Verkerke","sequence":"additional","affiliation":[{"name":"Department of Rehabilitation, University of Groningen, University Medical Center Groningen, Medicine, 9713 GZ Groningen, The Netherlands"},{"name":"Department of Biomedical Engineering, University of Twente, 7522 NB Enschede, The Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,5,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"359","DOI":"10.1007\/s00484-017-1352-y","article-title":"Occupational heat stress assessment and protective strategies in the context of climate change","volume":"62","author":"Gao","year":"2018","journal-title":"Int. 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