Effective volume of rebreathed air during breathing with facepieces increases with protection class and decreases with ambient airflow

• Helen Ngo,

  Roles Data curation, Formal analysis, Investigation, Writing – original draft

  Affiliation Faculty of Medicine, Department of Anesthesiology and Critical Care, Medical Center-University of Freiburg, University of Freiburg, Freiburg, Germany

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• Johannes Spaeth,

  Roles Conceptualization, Methodology, Writing – review & editing

  Affiliation Faculty of Medicine, Department of Anesthesiology and Critical Care, Medical Center-University of Freiburg, University of Freiburg, Freiburg, Germany

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• Stefan Schumann

  Roles Conceptualization, Formal analysis, Methodology, Visualization, Writing – original draft

  * E-mail: stefan.schumann@uniklinik-freiburg.de

  Affiliation Faculty of Medicine, Department of Anesthesiology and Critical Care, Medical Center-University of Freiburg, University of Freiburg, Freiburg, Germany

  https://orcid.org/0000-0003-0773-7489

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