Có nên đeo khẩu trang trong suốt buổi lễ không?

Mask wearing is down to your own personal Risk Assessments. It is recommended to be worn when creating a lot of dust. The blue disposable versions are ineffective though. I would recommend an N95 or N99 or an FFP2 or FFP3. These can be reusable with good care and are far more efficient at preventing dust inhalation.