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Do Large Ears Have an Advantage in Preventing Airborne Transmission?
Komiya Kosaku1, Kazufumi Hiramatsu1, Jun-Ichi Kadota1
1Respiratory Medicine and Infectious Diseases, Oita University Faculty of Medicine, Yufu, JPN.
Abstract:
Although double masking provides better protection against COVID-19 than single masking, the exact number of masks needed to achieve the most significant protection has not been determined to date. The present study investigated the changes in leakage with the use of surgical masks in a healthy person in terms of the number of masks. When the number of masks reached the upper limit that could be worn on the ears, large plastic ear attachments were used for each ear. The leakage rate related to the use of a single mask was approximately 50%, and with two masks, it was significantly reduced to approximately 30%. However, the leakage rate increased to approximately 45% with the use of three and four masks. When more than four masks were worn, the rate gradually decreased. Conversely, the rate for three-seven masks was not significantly lower than that for two masks. Although individuals with large ears might be able to wear more than five masks, the use of more than two masks would not be significantly better than the use of two masks.
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