The specific use time of a kn95 disposable face mask    needs to be determined according to the situation after wearing it. Generally, it can be used for 4 to 6 hours, and no more than eight hours at most.

Do not use the mask for too long, and do not use it repeatedly, otherwise the respiratory impedance will drop significantly. At present, for the prevention of new coronavirus, KN95 masks are recommended to be used for no more than eight hours, and can generally be used for 4 to 6 hours. Once the mask is contaminated by the patient's blood, respiratory secretions, and other body fluids, it needs to be replaced in time.

The use of KN95 masks must be determined according to the personal situation and environment. Once discomfort such as difficulty in breathing occurs, it is necessary to go to a place with fewer people and fresh air in time. If there is obvious discomfort, please seek medical treatment in time to avoid delay in treatment.

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