{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,28]],"date-time":"2026-09-28T12:00:48Z","timestamp":1790596848707,"version":"4.1.0"},"reference-count":24,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,9,28]],"date-time":"2026-09-28T00:00:00Z","timestamp":1790553600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100007210","name":"Varian Medical Systems","doi-asserted-by":"publisher","id":[{"id":"10.13039\/100007210","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Oncol."],"abstract":"<jats:p>The use of ultra-high dose rate (UHDR) radiation for radiotherapy could potentially improve outcomes for cancer patients by increasing healthy tissue sparing, known as the FLASH effect. As UHDR use expands in FLASH research and clinical translation, reassessing existing radiation safety programs is essential to determine whether UHDR beams introduce any new radiation safety requirements. This manuscript outlines the lessons learnt through investigations performed by members of the Varian FLASH forward consortium radiation protection working group. The information contained within is the consensus of the working group, as agreed, through discussions and reports during the monthly meetings. The paper brings together multi-institutional radiation protection experience from five Varian ProBeam type facilities engaged in preclinical and clinical proton FLASH research. Three main aspects of radiation protection are considered: shielding, activation, and accident scenarios. Lessons learned from the collective experience gained are presented to benefit those embarking on new proton FLASH research programs.<\/jats:p>","DOI":"10.3389\/fonc.2026.1862653","type":"journal-article","created":{"date-parts":[[2026,9,28]],"date-time":"2026-09-28T11:25:25Z","timestamp":1790594725000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Radiation protection considerations for\u00a0ultra-high dose rate proton beam FLASH research: consensus from multi-institutional experience"],"prefix":"10.3389","volume":"16","author":[{"given":"Michael J.","family":"Taylor","sequence":"first","affiliation":[{"name":"Division of Cancer Sciences, University of Manchester and the Christie NHS Foundation Trust","place":["Manchester, United Kingdom"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Christopher","family":"Bayer","sequence":"additional","affiliation":[{"name":"Varian, A Siemens Healthineers Company","place":["Palo Alto, CA, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gerard","family":"Paquet","sequence":"additional","affiliation":[{"name":"Varian, A Siemens Healthineers Company","place":["Palo Alto, CA, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nilendu","family":"Gupta","sequence":"additional","affiliation":[{"name":"Department of Radiation Oncology, The Ohio State University","place":["Columbus, OH, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Michael A.","family":"Lamba","sequence":"additional","affiliation":[{"name":"Department of Radiation Oncology, University of Cincinnati College of Medicine, Cincinnati Children\u2019s Hospital Medical Center","place":["Cincinnati, OH, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Haibo","family":"Lin","sequence":"additional","affiliation":[{"name":"Medical Physics and Dosimetry, New York Proton Center","place":["New York, NY, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sina","family":"Mossahebi","sequence":"additional","affiliation":[{"name":"Department of Radiation Oncology, University of Maryland School of Medicine","place":["Baltimore, MD, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yannick","family":"Poirier","sequence":"additional","affiliation":[{"name":"Department of Radiation Oncology, University of Maryland School of Medicine","place":["Baltimore, MD, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zhiyan","family":"Xiao","sequence":"additional","affiliation":[{"name":"Department of Radiation Oncology, University of Cincinnati College of Medicine, Cincinnati Children\u2019s Hospital Medical Center","place":["Cincinnati, OH, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Francis","family":"Yu","sequence":"additional","affiliation":[{"name":"Medical Physics and Dosimetry, New York Proton Center","place":["New York, NY, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Daniel R.","family":"Owen","sequence":"additional","affiliation":[{"name":"Varian, A Siemens Healthineers Company","place":["Palo Alto, CA, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Richard A.","family":"Amos","sequence":"additional","affiliation":[{"name":"Department of Medical Physics and Biomedical Engineering, University College London","place":["London, United Kingdom"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wendy L.","family":"Smith","sequence":"additional","affiliation":[{"name":"Varian, A Siemens Healthineers Company","place":["Palo Alto, CA, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,9,28]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","DOI":"10.1016\/j.ijrobp.2022.05.038","article-title":"Normal tissue sparing by FLASH as a function of single-fraction dose: A quantitative analysis","volume":"114","author":"B\u00f6hlen","year":"2022","journal-title":"Int J Radiat Oncol Biol Phys"},{"key":"B2","doi-asserted-by":"publisher","DOI":"10.1667\/rade-24-00117.1","article-title":"What's in a proton FLASH beam? 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