For the filter material of a good protective mask, the following three conditions should be met. One is that the filter efficiency is high when the mask is in good contact with the user's face, the other is that the breathing resistance is small, and the third is that the user feels comfortable. There are many materials for the filter material of dust-proof masks, including ordinary fabrics, animal hair, and non-woven fabrics. Very popular in the national standard is an activated carbon felt material.
The structure of the gauze mask has poor adhesion to the human face. Many small particles that are extremely harmful to us will enter the respiratory tract to the lungs through the gap between the mask and the face.
The filter material is usually some mechanical fabric. The only way to achieve high dust blocking efficiency is to increase the thickness, and the negative effect of increasing the thickness is to make the user feel that the breathing resistance is great and feel uncomfortable. The electrostatically treated non-woven fabric can not only block large dust particles, but also the electrostatic charge attached to its surface can absorb fine dust through electrostatic attraction, achieving high dust blocking efficiency. The thickness of the filter material is very thin, which greatly reduces the user's breathing resistance and feels comfortable, thus achieving the three necessary conditions for a good filter material we mentioned earlier. With a good filter material and a scientifically designed mask structure, it constitutes an efficient and high-quality mask.
The mask must be the right size and the way of wearing it must be correct for the mask to be effective. Masks sold on the market are generally divided into rectangular and cup-shaped. Rectangular masks must have at least three layers of paper structure to have a protective effect. The user has to press the iron wire of the mask on the bridge of the nose, and then spread the entire mask along the bridge of the nose to be effective. Children can wear a rectangular surgical mask because it has no fixed shape, and if it is tied well, it can fit tightly on the child's face.
For cup masks, make sure that the density of the mask is sufficient after being attached to the face so that the exhaled air will not leak out to be effective. When wearing a cup-shaped mask, you can try to blow air with your hands over the mask to check whether there is air leaking from the edge of the mask. If the mask cover is not tight, readjust the position before wearing it.