What should I pay attention to for medical masks?

Medical masks should try to avoid repeated use

     In winter, many people who go out wear masks to keep warm and block the dust in the air. Yesterday, during the reporter's visit, some people wearing masks were still uncomfortable. Doctors recommend medical masks.

     Wearing ordinary masks in haze weather cannot block harmful particles in the air, so you can buy medical masks in pharmacies and replace them frequently, otherwise they will be more dirty than smog.