{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,29]],"date-time":"2026-09-29T10:55:34Z","timestamp":1790679334807,"version":"4.1.0"},"reference-count":46,"publisher":"MDPI AG","issue":"17","license":[{"start":{"date-parts":[[2022,9,3]],"date-time":"2022-09-03T00:00:00Z","timestamp":1662163200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"European Union","award":["CE1226"],"award-info":[{"award-number":["CE1226"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJERPH"],"abstract":"<jats:p>Reducing children\u2019s exposure to air pollutants should be considered a primary goal, especially for the most vulnerable subjects. The goal of this study was to test the effectiveness of applying a protocol in the event of alert days, i.e., days with forecasted PM10 levels above the EU limit value (50 \u00b5g\/m3). The test was conducted, before the onset of SARS-CoV-2 restrictions, in a classroom of a primary school in Parma (Italy)\u2014a highly polluted area in Northern Italy. The protocol included indications for the frequency of opening windows and doors, as well as the activation of an air purifier. Teachers and students were asked to apply the protocol only in the event of alert days, while no indications were provided for non-alert days. A monitoring system measuring PM1, PM2.5, PM10, CO2, and NO2 was deployed in the classroom. Measurements of the same parameters were also performed outdoors near the school. The application of the protocol reduced the indoor\/outdoor (I\/O) ratio for all toxic pollutants. The reduction was also remarkable for PM10\u2014the most critical air quality parameter in the study area (1.5 and 1.1 for non-alert and alert days, respectively). Indoor concentrations of PM10\u2014especially during non-alert days\u2014were often higher than outdoors, showing a major contribution from resuspension due to the movement of people and personal cloud. The protocol did not cause any increase in indoor CO2 levels. Our findings showed that the application of a ventilation protocol together with the contribution of an air purifier may represent an effective way to reduce children\u2019s exposure to air pollution during severe air pollution episodes. Considering the onset of COVID-19 and the airborne transmission of pathogens, this protocol now has more meaningful implications for children\u2019s welfare, and can be integrated with protocols designed as measures against the spread of SARS-CoV-2.<\/jats:p>","DOI":"10.3390\/ijerph191711019","type":"journal-article","created":{"date-parts":[[2022,9,6]],"date-time":"2022-09-06T05:17:23Z","timestamp":1662441443000},"page":"11019","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Effectiveness of a Protocol to Reduce Children\u2019s Exposure to Particulate Matter and NO2 in Schools during Alert Days"],"prefix":"10.3390","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7452-9765","authenticated-orcid":false,"given":"Stefano","family":"Zauli-Sajani","sequence":"first","affiliation":[{"name":"Regional Agency for Prevention Environment and Energy of Emilia-Romagna (Arpae), 40139 Bologna, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0260-9007","authenticated-orcid":false,"given":"Stefano","family":"Marchesi","sequence":"additional","affiliation":[{"name":"Regional Agency for Prevention Environment and Energy of Emilia-Romagna (Arpae), 40139 Bologna, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Giuseppe","family":"Boselli","sequence":"additional","affiliation":[{"name":"Regional Agency for Prevention Environment and Energy of Emilia-Romagna (Arpae), 40139 Bologna, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Elisa","family":"Broglia","sequence":"additional","affiliation":[{"name":"Municipality of Parma, 43121 Parma, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alessandro","family":"Angella","sequence":"additional","affiliation":[{"name":"Municipality of Parma, 43121 Parma, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8745-9564","authenticated-orcid":false,"given":"Elena","family":"Maestri","sequence":"additional","affiliation":[{"name":"Consorzio Interuniversitario Nazionale per le Scienze Ambientali (CINSA), Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, 43124 Parma, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nelson","family":"Marmiroli","sequence":"additional","affiliation":[{"name":"Consorzio Interuniversitario Nazionale per le Scienze Ambientali (CINSA), Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, 43124 Parma, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Annamaria","family":"Colacci","sequence":"additional","affiliation":[{"name":"Regional Agency for Prevention Environment and Energy of Emilia-Romagna (Arpae), 40139 Bologna, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,9,3]]},"reference":[{"key":"ref_1","unstructured":"European Environmental Agency (2019). 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