What mask should I wear in foggy weather?

In foggy days, many people wear masks to go out. Experts also stressed that citizens should wear masks when traveling. However, there are a variety of mask products on the market now, which inevitably makes us feel dazzled. We can't help asking: what mask should I wear in foggy days?

Wearing a mask is very particular. Masks sold in the market are generally divided into rectangular and cup-shaped ones. When using a rectangular mask, the metal wire on the mask should be pressed on the bridge of the nose, and then the whole mask should be unfolded along the bridge of the nose to play a role. Children can wear a rectangular surgical mask because it has no fixed shape. If it is well tied, it can be glued to the child's face. A cup-shaped mask is effective only if it is tightly attached to the face and the exhaled air does not leak out. When wearing a cup-shaped mask, you can cover the mask with your hand and try to blow it to check whether there is air leakage at the edge of the mask. If the mask cover is not tight, it should be reset before wearing it.

In addition to the shape, masks are also divided into styles, including ordinary, sterilized, cotton masks, activated carbon masks, and N95 and KN90 masks that are popular these days. So what are N95 and KN90 masks? According to professionals, if the capture capacity of the mask for particles smaller than 2.5 microns is 90%, it is KN90, and if the capture capacity is 95%, it is N95.

Doctors suggest that ordinary people are more suitable to wear KN90 masks in smoggy weather. In this foggy weather, ordinary cotton masks basically have no protective effect; Although N95 can filter 95% of PM2.5, it is not suitable for ordinary people because of its poor sealing and air permeability.

The doctor reminded that wearing N95 professional protective mask should be trained, otherwise it is easy to cause breathing difficulties. For special groups, such as children, the elderly, patients with respiratory diseases and cardiovascular diseases, we should choose carefully. In contrast, KN90 mask is more suitable for ordinary people. Although the nose and mouth are a little tight, it has no effect on normal work and life.

In addition, the sterilization grade and ordinary grade marked on the outer packaging of the mask are only the cleanliness of the mask itself, and have nothing to do with the filtration effect.

Although experts recommend wearing masks when traveling in foggy days, masks should not be worn for a long time. Because the blood circulation of human nasal mucosa is very strong, the channels in nasal cavity are tortuous, and nasal hair forms a filter "barrier". When air is inhaled into the nostrils, the airflow forms a vortex in the tortuous channel, which warms the airflow inhaled into the nasal cavity. If you wear a mask for a long time, it will make the nasal mucosa fragile and lose the original physiological function of the nasal cavity, so you can't wear a mask for a long time.