Ant Manor’s answer on January 29th: In which case do I need to replace the disposable medical mask in time? The answer is that the mask is obviously wet. If you answer correctly, hurry up and get 180g of chicken feed per day!
Experts suggest that disposable medical masks are generally recommended to be used for 4 to 6 hours. If worn continuously for more than 4 hours in densely populated places, it is recommended to replace the mask once. When the mask becomes damp or contaminated with moisture, its protective ability will decrease and it needs to be replaced in time.