First, the dust blocking efficiency of the mask. The dust blocking efficiency of the mask is based on its blocking efficiency for fine dust, especially for respiratory dust below 5 microns. Because this size of dust can directly enter the alveoli, it has the greatest impact on human health. In general gauze masks, the dust blocking principle is mechanical filtering, and that is, when the dust hits the gauze, it passes through layers of barriers and blocks some large particles of dust in the sand cloth. However, some fine dusts, especially those smaller than 5 microns, will pass through the gauze mesh and enter the respiratory system. At present, there are some dust masks abroad, and the filter material is composed of fibers filled with permanent static electricity. Those respiratory dusts smaller than 5 microns are attracted by static electricity and absorbed in the filter material during the process of passing through this filter material Dust really plays a role in preventing dust.
Second, the degree of closeness between the mask and the face shape. Air is like a stream of water, where it flows first where the resistance is small. When the shape of the mask is not close to the face, the dangerous objects in the air will leak into the airway from the non-closed place. Then, even if you choose a mask with the best filter material, it will not protect your health. Many foreign regulations and standards now stipulate that workers should conduct regular mask adhesion tests. The purpose is to ensure that workers choose the appropriate size masks and wear the masks in the correct steps.
Third, wear comfortably. The respiratory resistance should be small, the weight should be light, it should be hygienic and easy to maintain. In this way, workers will be happy to insist on wearing in the workplace and improve their work efficiency. Maintenance-free masks in foreign countries do not need to be cleaned or replaced. When the dust barrier is saturated or the mask is damaged, it is discarded. This not only ensures the hygiene of the mask but also saves the workers time and effort to maintain the mask. In addition, many masks adopt an arched shape, which can not only ensure a good adhesion with the shape of the face, but also reserve a certain space at the mouth and nose, which is comfortable to wear.