There are some key things to consider before using a KN95 face mask. First, you should never double-mask. This is because the two masks are not equal in terms of protection. Secondly, you should never use an international respirator that has an exhalation valve or vent. Although this is true of all face masks, the CDC suggests not using them together. Lastly, if you must use one, make sure that it fits comfortably.

Make sure that your face mask is stamped with the following information: "NIOSH Approved" or "FDA Approved," as well as the model number and lot number. You can also find the TC approval number. If you're unsure what this means, the C.D.C. has a useful infographic that shows the types of printing that you should look for. You can find it on the mask's label.

The mask should also be made in Korea. If it isn't, look for one with the required labeling. Project KN95 mask, an N95 nonprofit, recommends buying the masks from a Korean importer. Two such companies are Be Healthy and KMact. Happy Life lists five distributors in the U.S. That should be enough to get your hands on a KN95 mask. And remember, if you're worried about buying a fake one, make sure it is made by an N95-certified company.

While N95 masks are US-approved and have the same protective standards, the Chinese KN95 masks are considered equivalent to US N95s. However, it's worth noting that the Chinese versions of these masks are less effective than their US counterparts. The main difference is in the standards. In the United States, only N95 masks are approved for use in health care. If you're in an unknown situation, you should consider purchasing a non-certified mask.

Another important feature to look for in a mask is how much air pressure the product can contain. The pressure drop of a KN95 mask is higher than that of an N95 mask, but you won't die from lack of oxygen. This is because N95 masks have stricter requirements. When you wear them, you'll have less of a pressure drop when inhaling than a KN95 mask. So if you're worried that you might end up breathing too much, buy a N95 mask.

As a side note, KN95 masks are not FDA-approved, but they meet other requirements that an N95 mask cannot. According to Dr. Nina Shapiro, a UCLA professor of head and neck surgery, KN95 masks are more effective at filtering particulate matter than N95 masks. The latter is designed to protect the wearer from airborne particles, including large and small particles. There are even fake KN95 masks on the market that don't meet these standards.