11

Mask filter material and fitting effect

2020-5-27

  Mask filter material

  For the filter material of a good protective mask, the following three conditions should be met. First, the filter efficiency is high when the mask is close to the user's face, second, the respiratory resistance is small, and third, the user feels comfortable. There are many kinds of materials for dust masks, including ordinary fabrics, animal hair, non-woven fabrics, etc. Activated carbon felt material is very popular in the national standard.

  The structure of the gauze mask is very inadequate to the human face. Many fine particles that are extremely harmful to us will enter the respiratory tract to the lungs through the gap between the mask and the face. Its filter material is usually some mechanical fabric. The only way to achieve high dust resistance is to increase the thickness, and the negative effect of increasing the thickness is to make the user feel that the breathing resistance is very large and uncomfortable. The non-woven fabric after electrostatic treatment can not only block large dust particles, but also the static charge attached to its surface can attract fine dust through electrostatic attraction, achieving a high dust suppression 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 of the good filter material we mentioned earlier. With a good filter material and a scientifically designed mask structure, an efficient and high-quality mask is formed.

  Fitting effect

  The mask must be the right size and the way to wear it must be correct for the mask to be effective. Masks on the market are generally divided into two types, rectangular and cup-shaped. A rectangular mask must have a structure of at least three layers of paper in order to have a protective effect. The user needs to press the iron wire on the mask against the bridge of the nose, and then spread the entire mask along the bridge of the nose in order to exert the effect. Let the child wear a rectangular surgical mask because it has no fixed shape, and if it is tied well, it can be close to the child's face. Cup-shaped masks must ensure that the masks have sufficient density after they are attached to the face, so that the exhaled air will not leak out to be effective. When wearing a cup-shaped mask, cover the mask with both hands and try to blow air. Check whether there is air leakage from the edge of the mask. If the mask is not tight, you must readjust the position before wearing it.