{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,11,4]],"date-time":"2026-11-04T03:45:46Z","timestamp":1793763946132,"version":"4.6.1"},"reference-count":21,"publisher":"Wiley","license":[{"start":{"date-parts":[[2026,7,24]],"date-time":"2026-07-24T00:00:00Z","timestamp":1784851200000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"},{"start":{"date-parts":[[2026,7,24]],"date-time":"2026-07-24T00:00:00Z","timestamp":1784851200000},"content-version":"tdm","delay-in-days":0,"URL":"http:\/\/doi.wiley.com\/10.1002\/tdm_license_1.1"}],"content-domain":{"domain":["onlinelibrary.wiley.com"],"crossmark-restriction":true},"short-container-title":["Photochem &amp;amp; Photobiology"],"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>\n                    The purpose of this study is to examine irradiation conditions of 222\u2009nm Far\u2010UVC that do not cause ocular discomfort to participants, considering both the irradiation intensity (ODF\u2010IT; ocular\u2010discomfort\u2010free irradiance threshold) and irradiation dose (ODF\u2010DT; ocular\u2010discomfort\u2010free dose threshold). A prospective, single\u2010blind interventional study was conducted with 36\u2009healthy adults exposed to 222\u2009nm Far\u2010UVC under five different irradiation conditions varying in intensity and total dose, along with a visible\u2010light control condition. The irradiation device, placed under the TV monitor, delivered 222\u2009nm Far\u2010UVC or visible light to participants viewing the video. Ocular discomforts were recorded at multiple time points up to 24\u2009h. Ophthalmic examinations\u2014including slit lamp assessment, corneal fluorescein staining, and corneal endothelial cell density\u2014were performed before and after irradiation. No adverse changes were observed in spherical equivalent refractive error, or corneal endothelial cell density under any condition. Corneal fluorescein staining occurred in some cases but showed no consistent correlation with ocular discomfort. Discomfort was significantly associated with radiant exposure dose, video viewing time and time after video viewing. The ODF\u2010IT and ODF\u2010DT values of 222\u2009nm Far\u2010UVC determined by the present study were around \u22641.0\u2009\u03bcW\/cm\n                    <jats:sup>2<\/jats:sup>\n                    and approximately 5.5\u2009mJ\/cm\n                    <jats:sup>2<\/jats:sup>\n                    respectively.\n                  <\/jats:p>","DOI":"10.1111\/php.70137","type":"journal-article","created":{"date-parts":[[2026,7,24]],"date-time":"2026-07-24T12:39:24Z","timestamp":1784896764000},"update-policy":"https:\/\/doi.org\/10.1002\/crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Human ocular\u2010discomfort\u2010free thresholds for 222\u2009nm Far\u2010\n                    <scp>UVC<\/scp>\n                    irradiation: A prospective interventional study"],"prefix":"10.1111","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3324-6678","authenticated-orcid":false,"given":"Sachiko","family":"Kaidzu","sequence":"first","affiliation":[{"name":"Department of Ophthalmology Shimane University Faculty of Medicine  Izumo Shimane Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kazunobu","family":"Sugihara","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology Shimane University Faculty of Medicine  Izumo Shimane Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6512-7203","authenticated-orcid":false,"given":"Masaki","family":"Tanito","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology Shimane University Faculty of Medicine  Izumo Shimane Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"311","published-online":{"date-parts":[[2026,7,24]]},"reference":[{"key":"e_1_2_8_2_1","doi-asserted-by":"crossref","first-page":"483","DOI":"10.1667\/RR0010CC.1","article-title":"Germicidal efficacy and mammalian skin safety of 222\u2010nm UV light","volume":"187","author":"Buonanno M","year":"2017","journal-title":"Radiat Res"},{"key":"e_1_2_8_3_1","doi-asserted-by":"crossref","first-page":"2752","DOI":"10.1038\/s41598-018-21058-w","article-title":"Far\u2010UVC light: a new tool to control the spread of airborne\u2010mediated microbial diseases","volume":"8","author":"Welch D","year":"2018","journal-title":"Sci Rep"},{"key":"e_1_2_8_4_1","doi-asserted-by":"crossref","first-page":"10285","DOI":"10.1038\/s41598-020-67211-2","article-title":"Far\u2010UVC light (222 nm) efficiently and safely inactivates airborne human coronaviruses","volume":"10","author":"Buonanno M","year":"2020","journal-title":"Sci 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One"},{"key":"e_1_2_8_8_1","doi-asserted-by":"crossref","first-page":"611","DOI":"10.1080\/10715762.2019.1603378","article-title":"Evaluation of acute corneal damage induced by 222\u2010nm and 254\u2010nm ultraviolet light in Sprague\u2010Dawley rats","volume":"53","author":"Kaidzu S","year":"2019","journal-title":"Free Radic Res"},{"key":"e_1_2_8_9_1","doi-asserted-by":"crossref","first-page":"853","DOI":"10.1111\/php.13269","article-title":"Long\u2010term effects of 222\u2010nm ultraviolet radiation C sterilizing lamps on mice susceptible to ultraviolet radiation","volume":"96","author":"Yamano N","year":"2020","journal-title":"Photochem Photobiol"},{"key":"e_1_2_8_10_1","doi-asserted-by":"crossref","first-page":"505","DOI":"10.1111\/php.13419","article-title":"Re\u2010evaluation of rat corneal damage by short\u2010wavelength UV revealed extremely less hazardous property of far\u2010UV\u2010C(\u2020)","volume":"97","author":"Kaidzu S","year":"2021","journal-title":"Photochem Photobiol"},{"key":"e_1_2_8_11_1","doi-asserted-by":"crossref","first-page":"1142","DOI":"10.1111\/php.13750","article-title":"Safety evaluation of far\u2010UV\u2010C irradiation to epithelial basal cells in the corneal limbus","volume":"99","author":"Kaidzu S","year":"2023","journal-title":"Photochem Photobiol"},{"key":"e_1_2_8_12_1","doi-asserted-by":"crossref","first-page":"24052","DOI":"10.1038\/s41598-025-09241-2","article-title":"Corneal safety assessment of germicidal far UV\u2010C radiation","volume":"15","author":"Zamudio D\u00edaz DF","year":"2025","journal-title":"Sci Rep"},{"key":"e_1_2_8_13_1","doi-asserted-by":"crossref","first-page":"695","DOI":"10.1001\/archopht.1961.01840020697016","article-title":"Cell turnover in the adult human eye","volume":"65","author":"Hanna C","year":"1961","journal-title":"Arch Ophthalmol"},{"key":"e_1_2_8_14_1","first-page":"1442","article-title":"The X, Y, Z hypothesis of corneal epithelial maintenance","volume":"24","author":"Thoft 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