接触高危人群应该戴N95，除非呼吸不畅。一个N95相当于8个30%阻挡率的普通口罩。

来源: 周老大于 2022-01-31 08:10:37 [博客] [旧帖] [给我悄悄话] 本文已被阅读：次

WENXUECITY.COM does not represent or guarantee the truthfulness, accuracy, or reliability of any of communications posted by other users.