When do you need to change your mask
1. The mask is contaminated with foreign objects such as blood stains or droplets.
2. The user feels that the respiratory resistance becomes greater.
3. The mask is damaged.
4. Dust-proof filter cotton. When the mask is in close contact with the user's face, when the user feels that the breathing resistance is high, it means that the filter cotton is full of dust particles, and a new mask should be replaced.
5. Anti-virus filter box, under the condition that the mask and the user's face are in close contact, when the user smells the poison, it should be replaced with a new one.
6. Ordinary mask wearing: activated carbon mask can generally be used for 2 days, n95 can be used for a week. If the mask has not been worn for a long time after cleaning, it is better to wear it again.