Details of using the mask
Here are some details to keep in mind when wearing a disposable mask. 4 to 8 hours to replace a time, many friends repeated use of disposable protective masks, or a wear is a whole day, in fact, the end of the mask contact with the air has a lot of dust. Not the thicker the better, masks are used to block dust and prevent respiratory infections, but not the thicker the better, as long as there is a good shielding effect. Do not wear a mask when sneezing, coughing; less or no need for brightly colored masks, brightly colored or printed masks mostly have synthetic ingredients, easily irritate the nasal cavity and bronchial tubes, so choose colorless, odorless, breathable cotton masks. S ource: https://www.unisourcesgroup.com/news/32.html