{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,10]],"date-time":"2026-09-10T17:40:43Z","timestamp":1789062043480,"version":"build-2803163510"},"reference-count":46,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2025,3,29]],"date-time":"2025-03-29T00:00:00Z","timestamp":1743206400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100004837","name":"Spanish Ministry of Science and Innovation","doi-asserted-by":"publisher","award":["PID2022-136627NB-I00 (MCIN\/AEI\/10.13039\/501100011033\/FEDER, UE)"],"award-info":[{"award-number":["PID2022-136627NB-I00 (MCIN\/AEI\/10.13039\/501100011033\/FEDER, UE)"]}],"id":[{"id":"10.13039\/501100004837","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Gobernment of Navarra","award":["PID2022-136627NB-I00 (MCIN\/AEI\/10.13039\/501100011033\/FEDER, UE)"],"award-info":[{"award-number":["PID2022-136627NB-I00 (MCIN\/AEI\/10.13039\/501100011033\/FEDER, UE)"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This paper comprehensively investigates the performance of various strategies for predicting CO2 levels in school classrooms over different time horizons by using data collected through IoT devices. We gathered Indoor Air Quality (IAQ) data from fifteen schools in Navarra, Spain between 10 January and 3 April 2022, with measurements taken at 10-min intervals. Three prediction strategies divided into seven models were trained on the data and compared using statistical tests. The study confirms that simple methodologies are effective for short-term predictions, while Machine Learning (ML)-based models perform better over longer prediction horizons. Furthermore, this study demonstrates the feasibility of using low-cost devices combined with ML models for forecasting, which can help to improve IAQ in sensitive environments such as schools.<\/jats:p>","DOI":"10.3390\/s25072173","type":"journal-article","created":{"date-parts":[[2025,3,31]],"date-time":"2025-03-31T02:50:16Z","timestamp":1743389416000},"page":"2173","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["A Comparative Study of CO2 Forecasting Strategies in School Classrooms: A Step Toward Improving Indoor Air Quality"],"prefix":"10.3390","volume":"25","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2409-0106","authenticated-orcid":false,"given":"Peio","family":"Garcia-Pinilla","sequence":"first","affiliation":[{"name":"Institute of Smart Cities (ISC), Public University of Navarra (UPNA), Campus de Arrosadia, 31006 Pamplona, Spain"},{"name":"inBiot Monitoring, P\u00baSantxiki, 2 LB5, 31192 Mutilva Alta, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4087-586X","authenticated-orcid":false,"given":"Aranzazu","family":"Jurio","sequence":"additional","affiliation":[{"name":"Institute of Smart Cities (ISC), Public University of Navarra (UPNA), Campus de Arrosadia, 31006 Pamplona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5845-887X","authenticated-orcid":false,"given":"Daniel","family":"Paternain","sequence":"additional","affiliation":[{"name":"Institute of Smart Cities (ISC), Public University of Navarra (UPNA), Campus de Arrosadia, 31006 Pamplona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,3,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"427","DOI":"10.1038\/sj.jea.7500244","article-title":"It\u2019s about time: A comparison of Canadian and American time\u2013activity patterns","volume":"12","author":"Leech","year":"2002","journal-title":"J. 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