How many hours should a disposable medical use mask be replaced after being worn continuously?

How many hours should a disposable medical use mask be replaced after being worn continuously?
Replace after 4 hours.
Ordinary medical surgical masks can resist the chance of virus infection, but disposable medical use mask is generally disposable, it is recommended to wear
No more than 4 hours, if a mask is worn repeatedly, in this case, the mask will be contaminated with some dust, bacteria, moisture and saliva
If the fluid cannot be changed frequently, these residual bacteria and viruses will not only fail to protect, but may also have adverse effects.
If it's just ordinary people, take it with you when you go out, then in this case, you can appropriately extend the replacement time, but generally the second
It is also necessary to replace the new mask every day, and the mask should be replaced in time in the following situations:
1. The air quality is bad, and the places you go to are crowded, such as supermarkets, markets, cinemas, playgrounds, and the viruses contained in the air are more
It is more likely to be infected, and the mask is not recommended to be reused.
2. If the mouth is polluted, such as sputum, secretions, and dust on it, it will not be able to prevent the virus.
Disposable medical use mask should be replaced in time and must not be reused.