{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,8]],"date-time":"2026-09-08T00:49:45Z","timestamp":1788828585968,"version":"build-2803163510"},"reference-count":36,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2025,3,21]],"date-time":"2025-03-21T00:00:00Z","timestamp":1742515200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"European Union Committee","award":["2023-1-IT02-KA220-HED-000162181"],"award-info":[{"award-number":["2023-1-IT02-KA220-HED-000162181"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This study investigates indoor air quality (IAQ) and thermal comfort in Italian university classrooms, considering seasonal variations. Poor IAQ can impair students\u2019 cognitive performance and well-being, making ventilation strategies crucial. The aim is to assess CO2 levels, temperature, and humidity, analyzing their interactions across seasons. A monitoring protocol was applied in three classrooms using NDIR sensors and a microclimate assessment system. Sensors were placed strategically to capture representative data in 20 days in spring and autumn. Results indicate that CO2 levels peaked at 2324.2 ppm in autumn, significantly exceeding the 1000 ppm threshold, whereas spring levels remained below 953.4 ppm. Relative humidity ranged from 32.7% to 55.6%, with higher values in autumn. Temperatures varied from 19.1 \u00b0C to 27.5 \u00b0C, with warmer conditions in spring. Strong positive correlations (always greater than 0.70) between CO2 and humidity suggest inadequate air exchange reduces IAQ, potentially affecting cognitive performance. This research provides valuable insights for improving student well-being through better air quality management. This research provides valuable insights for optimizing classroom environments, supporting cognitive performance, and improving student well-being through better air quality management.<\/jats:p>","DOI":"10.3390\/s25071970","type":"journal-article","created":{"date-parts":[[2025,3,21]],"date-time":"2025-03-21T11:06:48Z","timestamp":1742555208000},"page":"1970","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Measuring CO2 Concentration and Thermal Comfort in Italian University Classrooms: A Seasonal Analysis"],"prefix":"10.3390","volume":"25","author":[{"given":"Alessia","family":"Fedele","sequence":"first","affiliation":[{"name":"Department of Economics, Engineering, Society and Business Organization, University of Tuscia, 01100 Viterbo, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5330-6076","authenticated-orcid":false,"given":"Andrea","family":"Colantoni","sequence":"additional","affiliation":[{"name":"Department of Agriculture and Forest Sciences, University of Tuscia, 01100 Viterbo, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7277-1125","authenticated-orcid":false,"given":"Giuseppe","family":"Calabr\u00f2","sequence":"additional","affiliation":[{"name":"Department of Economics, Engineering, Society and Business Organization, University of Tuscia, 01100 Viterbo, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mauro","family":"Scungio","sequence":"additional","affiliation":[{"name":"Department of Economics, Engineering, Society and Business Organization, University of Tuscia, 01100 Viterbo, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0006-7013","authenticated-orcid":false,"given":"Stefano","family":"Rossi","sequence":"additional","affiliation":[{"name":"Department of Economics, Engineering, Society and Business Organization, University of Tuscia, 01100 Viterbo, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8997-7605","authenticated-orcid":false,"given":"Juri","family":"Taborri","sequence":"additional","affiliation":[{"name":"Department of Economics, Engineering, Society and Business Organization, University of Tuscia, 01100 Viterbo, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,3,21]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"110436","DOI":"10.1016\/j.rser.2020.110436","article-title":"Measuring the Right Factors: A Review of Variables and Models for Thermal Comfort and Indoor Air Quality","volume":"135","author":"Ma","year":"2021","journal-title":"Renew. 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