{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,6]],"date-time":"2026-03-06T02:12:46Z","timestamp":1772763166839,"version":"3.50.1"},"reference-count":29,"publisher":"MDPI AG","issue":"14","license":[{"start":{"date-parts":[[2021,7,6]],"date-time":"2021-07-06T00:00:00Z","timestamp":1625529600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"The HSBC 150th Anniversary Charity Programme and Special Fund Project for Science and Technology Innovation Strategy of Guangdong Province","award":["2019B121205004"],"award-info":[{"award-number":["2019B121205004"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Sensor technology has enabled the development of portable low-cost monitoring kits that might supplement many applications in conventional monitoring stations. Despite the sensitivity of electrochemical gas sensors to environmental change, they are increasingly important in monitoring polluted microenvironments. The performance of a compact diffusion-based Personal Exposure Kit (PEK) was assessed for real-time gaseous pollutant measurement (CO, O3, and NO2) under typical environmental conditions encountered in the subtropical city of Hong Kong. A dynamic baseline tracking method and a range of calibration protocols to address system performance were explored under practical scenarios to assess the performance of the PEK in reducing the impact of rapid changes in the ambient environment in personal exposure assessment applications. The results show that the accuracy and stability of the ppb level gas measurement is enhanced even in heterogeneous environments, thus avoiding the need for data post-processing with mathematical algorithms, such as multi-linear regression. This establishes the potential for use in personal exposure monitoring, which has been difficult in the past, and for reporting more accurate and reliable data in real-time to support personal exposure assessment and portable air quality monitoring applications.<\/jats:p>","DOI":"10.3390\/s21144637","type":"journal-article","created":{"date-parts":[[2021,7,6]],"date-time":"2021-07-06T11:36:44Z","timestamp":1625571404000},"page":"4637","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":18,"title":["Reducing the Influence of Environmental Factors on Performance of a Diffusion-Based Personal Exposure Kit"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2858-3327","authenticated-orcid":false,"given":"Huixin","family":"Zong","sequence":"first","affiliation":[{"name":"Division of Environment and Sustainability, The Hong Kong University of Science and Technology, Hong Kong, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2233-8761","authenticated-orcid":false,"given":"Peter","family":"Brimblecombe","sequence":"additional","affiliation":[{"name":"Department of Marine Environment and Engineering, National Sun Yat-sen University, Kaohsiung 80424, Taiwan"}]},{"given":"Li","family":"Sun","sequence":"additional","affiliation":[{"name":"Division of Environment and Sustainability, The Hong Kong University of Science and Technology, Hong Kong, China"}]},{"given":"Peng","family":"Wei","sequence":"additional","affiliation":[{"name":"Division of Environment and Sustainability, The Hong Kong University of Science and Technology, Hong Kong, China"}]},{"given":"Kin-Fai","family":"Ho","sequence":"additional","affiliation":[{"name":"JC School of Public Health and Primary Care, The Chinese University of Hong Kong, Hong Kong, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0587-1748","authenticated-orcid":false,"given":"Qingli","family":"Zhang","sequence":"additional","affiliation":[{"name":"Key Laboratory of Public Health Safety, Ministry of Education, Fudan University, Shanghai 200433, China"},{"name":"Department of Environmental Health, School of Public Health, Fudan University, Shanghai 200032, China"}]},{"given":"Jing","family":"Cai","sequence":"additional","affiliation":[{"name":"Key Laboratory of Public Health Safety, Ministry of Education, Fudan University, Shanghai 200433, China"},{"name":"Department of Environmental Health, School of Public Health, Fudan University, Shanghai 200032, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1871-8999","authenticated-orcid":false,"given":"Haidong","family":"Kan","sequence":"additional","affiliation":[{"name":"Key Laboratory of Public Health Safety, Ministry of Education, Fudan University, Shanghai 200433, China"},{"name":"Department of Environmental Health, School of Public Health, Fudan University, Shanghai 200032, China"}]},{"given":"Mengyuan","family":"Chu","sequence":"additional","affiliation":[{"name":"Division of Environment and Sustainability, The Hong Kong University of Science and Technology, Hong Kong, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1337-965X","authenticated-orcid":false,"given":"Wenwei","family":"Che","sequence":"additional","affiliation":[{"name":"Division of Environment and Sustainability, The Hong Kong University of Science and Technology, Hong Kong, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3802-828X","authenticated-orcid":false,"given":"Alexis Kai-Hon","family":"Lau","sequence":"additional","affiliation":[{"name":"Division of Environment and Sustainability, The Hong Kong University of Science and Technology, Hong Kong, China"}]},{"given":"Zhi","family":"Ning","sequence":"additional","affiliation":[{"name":"Division of Environment and Sustainability, The Hong Kong University of Science and Technology, Hong Kong, China"}]}],"member":"1968","published-online":{"date-parts":[[2021,7,6]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"997","DOI":"10.1016\/S0890-6955(02)00040-8","article-title":"A summary of methods applied to tool condition monitoring in drilling","volume":"42","author":"Jantunen","year":"2002","journal-title":"Int. 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