Is the protection level of KN95 and N95 the same?
KN95 level is one of the levels specified in the Chinese standard GB2626-2006, and N95 is one of the levels specified in the American standard 42 CFR 84. The technical requirements and test methods of these two levels are basically the same, but they belong to the standards of different countries.
Can masks prevent secondhand smoke?
Protective masks cannot completely protect against second-hand smoke. Choosing CM Chaomei’s high-efficiency anti-particulate masks with activated carbon can indeed filter out most of the particulates. However, because the amount of activated carbon is very limited, the particulates filtered on the mask continue to volatilize odors. For a person with a sufficiently sensitive sense of smell, it still feels smelly, and then it is possible to doubt the protective effect of protective masks and reduce the exposure of second-hand smoke. The effective way is to ventilate.
