Different countries use different codes and numbers to name their respiratory face masks, The N95 is the USA standard, The KN95 is the China standard, FFP2 is the EU standard. They all can protect you from inhaling respiratory droplets, the 95 means that a KN95 has a 95 percent efficiency.
Filtering facepiece respirators (FFR) are sometimes called disposable face masks and are subject to various regulatory standards around the world. These standards specify certain required physical properties and performance characteristics in order to claim compliance with a particular standard. During pandemic or emergency situations, health authorities often reference these standards when making recommendations for face masks. For example stating certain populations should use a KN95, N95 or equivalent respirator. The below table shows KN95 face masks and N95 facce masks function are very similar to one another.
Based on the above comparison, it is reasonable to consider KN95 as equivalent to N95 for filtering non-oil based particles such as those resulting from wildfires, PM 2.5 air pollution, volcanic eruptions, or bioaerosols. (e.g. viruses such as the coronavirus)
