{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,16]],"date-time":"2026-07-16T03:37:01Z","timestamp":1784173021677,"version":"3.55.0"},"reference-count":38,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2025,9,3]],"date-time":"2025-09-03T00:00:00Z","timestamp":1756857600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Panasonic Co., Ltd."}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Microorganisms"],"abstract":"<jats:p>Airborne and surface-residing microorganisms in indoor environments pose potential risks for infectious disease transmission. To address this issue, we developed a composite device combining a generator of vaporized free chlorine components with a fine particle removal filter. Field tests were conducted in occupied university classrooms to evaluate the device\u2019s efficacy in reducing airborne bacterial loads. Airborne bacteria were sampled under three operational conditions [Electrolyzed (+)\/Filter (+), Electrolyzed (\u2212)\/Filter (+), and Electrolyzed (\u2212)\/Filter (\u2212)]. Significant reductions in bacterial counts were observed in the Electrolyzed (+)\/Filter (+) condition, with a residual rate of 14.5% after 2.25 h (p = 0.00001). Additionally, surface contact tests demonstrated that vaporized free chlorine components, primarily consisting of hypochlorous acid (HOCl), reduced viable counts of E. coli, P. aeruginosa, and S. aureus by 59.0\u201399.7% even at a distance of 8.0 m. The concentrations of vaporized free chlorine components during operation remained within safe exposure limits (0\u201319 ppb), consistent with the effective range reported in prior literature (10\u201350 ppb). Computational fluid dynamics simulations confirmed the diffusion of vaporized free chlorine components throughout the room, including distant sampling points. These findings suggest the combined use of a vaporized free chlorine generator and a particulate filter effectively reduces microbial contamination in indoor environments, providing a promising approach for infection control in residential and public settings.<\/jats:p>","DOI":"10.3390\/microorganisms13092053","type":"journal-article","created":{"date-parts":[[2025,9,3]],"date-time":"2025-09-03T15:15:57Z","timestamp":1756912557000},"page":"2053","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Control of Airborne and Surface Microorganisms in Real Indoor Environments Using an Integrated System of Vaporized Free Chlorine Components and Filtration"],"prefix":"10.3390","volume":"13","author":[{"given":"Saki","family":"Kawahata","sequence":"first","affiliation":[{"name":"Panasonic Ecology Systems Co., Ltd., Kasugai 486-8522, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mayumi","family":"Kondo","sequence":"additional","affiliation":[{"name":"Department of Clinical Engineering, Faculty of Medical Science and Technology, Gunma Paz University, Takasaki 370-0006, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Atsushi","family":"Yamada","sequence":"additional","affiliation":[{"name":"Panasonic Ecology Systems Co., Ltd., Kasugai 486-8522, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Naoya","family":"Shimazaki","sequence":"additional","affiliation":[{"name":"Department of Clinical Engineering, Faculty of Medical Science and Technology, Gunma Paz University, Takasaki 370-0006, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Makoto","family":"Saito","sequence":"additional","affiliation":[{"name":"Department of Clinical Engineering, Faculty of Medical Science and Technology, Gunma Paz University, Takasaki 370-0006, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Takayoshi","family":"Takano","sequence":"additional","affiliation":[{"name":"Panasonic Ecology Systems Co., Ltd., Kasugai 486-8522, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tetsuyoshi","family":"Yamada","sequence":"additional","affiliation":[{"name":"Panasonic Ecology Systems Co., Ltd., Kasugai 486-8522, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yoshinobu","family":"Shimayama","sequence":"additional","affiliation":[{"name":"Panasonic Ecology Systems Co., Ltd., Kasugai 486-8522, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shunsuke","family":"Matsuoka","sequence":"additional","affiliation":[{"name":"Panasonic Ecology Systems Co., Ltd., Kasugai 486-8522, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hirokazu","family":"Kimura","sequence":"additional","affiliation":[{"name":"Department of Clinical Engineering, Faculty of Medical Science and Technology, Gunma Paz University, Takasaki 370-0006, Japan"},{"name":"Advanced Medical Science Research Center\/Research Facility Administration Office, Gunma Paz University Research Institute, Takasaki 370-0006, Japan"},{"name":"Department of Health Science, Gunma Paz University Graduate School of Health Science, Takasaki 370-0006, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,9,3]]},"reference":[{"key":"ref_1","first-page":"141","article-title":"Distribution Survey of Floating Bacteria in General Environments by Air Sampler","volume":"34","author":"Matsuki","year":"2019","journal-title":"Jpn. 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Control"}],"container-title":["Microorganisms"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2076-2607\/13\/9\/2053\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,9]],"date-time":"2025-10-09T18:39:00Z","timestamp":1760035140000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2076-2607\/13\/9\/2053"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,9,3]]},"references-count":38,"journal-issue":{"issue":"9","published-online":{"date-parts":[[2025,9]]}},"alternative-id":["microorganisms13092053"],"URL":"https:\/\/doi.org\/10.3390\/microorganisms13092053","relation":{},"ISSN":["2076-2607"],"issn-type":[{"value":"2076-2607","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,9,3]]}}}