How many days can an N95 mask be worn repeatedly?

When using disposable masks, you must pay attention to timely replacement. Generally, it is recommended to replace them every 4 hours. The timely replacement of masks can achieve better prevention effects.

N95 masks can filter more than 95% of the particulate matter in the air. They are a type of mask with a higher level of protection. How long it can be used depends on different environments.

1. Generally, it can be used for about 3 days

Some researchers have conducted related studies on the protection efficiency and wearing time of KN95 masks. The results showed that: N95 mask was worn for 2 days, the filtration efficiency remained above 95%, and the respiratory resistance did not change much. After 3 days, the filtration efficiency dropped to 94.7%. It can be seen that in the absence of an epidemic, N95 masks can be used for about 3 days.

2. During special periods such as epidemics, it is recommended to 4-6 hours, and the longest time is 8 hours

If you go out for a long time and enter densely populated places or epidemic areas, it is easier to come into contact with bacteria and viruses. It is recommended to change it every 4-6 hours; if you just walk in the community and do not go far away, the N95 mask can be worn multiple times. Just change one a day.

3. In the following situations, the mask should be replaced immediately

① During the epidemic, or in a crowded place, if the N95 mask is sneezing or coughing from the other side, it is contaminated and needs to be replaced in time;

② Discard the mask when it comes in contact with blood or droplets;

③ If the mask is damaged or the breathing resistance increases, it should be replaced in time.