接觸高危人群應該戴N95，除非呼吸不暢。一個N95相當於8個30%阻擋率的普通口罩。

來源: 周老大於 2022-01-31 08:10:37 [博客] [舊帖] [給我悄悄話] 本文已被閱讀：次

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