How to choose a face mask?
The dust-proof efficiency of the mask is based on its resistance to fine dust. In particular, the barrier efficiency for respirable dust below 2.5 microns is the standard. Because dust of this size can directly enter the alveoli, it has the greatest impact on human health. For gauze masks, the principle of dust blocking is mechanical filtration. That is, when the dust hits the gauze, it passes through layers of barriers, blocking some large particles of dust in the sand cloth. For some fine dust, especially dust less than 2.5 microns, it will pass through the mesh of the gauze and enter the respiratory system. Dust-proof mask, the filter material is composed of activated carbon fiber mat or non-woven fabric. Those respirable dust less than 2.5 microns are blocked during the process of passing through this filter material, and play a role in filtering the air.
The anti-side leakage design of the mask is to prevent air from passing through the gap between the mask and the human face without being inhaled through the filter. The technical requirements are considered. Air is like water flow, where the resistance is small, it flows first. When the shape of the mask is not close to the human face, the dangerous objects in the air will leak in from the non-close place and enter the human respiratory tract. So, even if you choose a mask with the best filter material. Nor can it protect your health. Many foreign regulations and standards stipulate that workers should regularly perform mask tightness tests. The purpose is to ensure that workers choose masks of the right size and wear masks in the correct steps.
