In the face of COVID-19, wearing masks has become the most important protective measure. KN95 masks have the highest protective effect among many masks. KN95 masks should be worn when entering and exiting areas with medium and high risks to achieve maximum protection. Yourself. Everyone knows that there are five layers of KN95 masks. Because there are two more layers of fabric than disposable masks, and the side of the mask is designed to fit the face completely, the KN95 masks will be boring to wear, and the breathability is relatively poor. Some people will choose KN95 masks with breathing valves.
However, during the period of normalization of prevention and control, it is not recommended to wear a respirator with a breathing valve, because a respirator with a breathing valve produces a one-way protective effect. If a sick person wears this kind of mask, the people around him are at risk of contracting the disease.