Wearing a mask, in 4 hours 
 
 
Lin Yong Southeast university affiliated zhongda hospital 
 
 
China's traditional Chinese medicine to 

        As they were leaving the haze, rampant, many people would wear more layer mask. In fact, resist PM2.5, masks and wear method are equally important. 
 
        PM2.5 is size is about 2.5 micron particle diameter, equivalent to 1/20 of a human hair. Common on the market of masks, non-woven mask, cotton gauze masks, surgical masks can stop the dust on the road, but on the adsorption effect of PM2.5 co., LTD. 
 
        N95 respirators, by contrast, the haze effect more ideal, of course it is also the tiny particles can not be completely "out". What need reminds is, wear a mask when had better change every 4 hours, because as the masks with harmful particles, such as no replacement will be inhaled, no dust-proof and haze effect not only, also be counterproductive. Gauze mask can be worn again after cleaning, surgical masks, N95 respirator is one-off, cannot repeat use. 
 
        A lot of people are not clear mask wearing the right way, thought that cover your mouth and nose will not have to worry about. In fact, wearing a mask is the key to fit closely face, don't show space. Because of dust and haze came from all directions, once the sewing is dew, they will. Surgical masks, for example, the top have a bending of metal strips, should press the metal strip with finger after wear, make the mask is clingy nose and cheeks on both sides, reoccupy hand pulling edge of masks, to that of the jaw joint.
 
 
 
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