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I have said it before and I’ll say it again. This is no time to coast when it comes to social distancing and masking. Even now that the number of people being vaccinated against COVID-19 is rising, this is no time to stop masking in public places, so let’s take this moment to review some basic information about masks and also to address a new question that may be on your mind, based on discussions that you may be hearing: Should you double mask? Particularly if you are pregnant, you may be wondering about the double masking issue, since is physically comforting already to be pregnant, so why add the aggravation of double masking.
To review from previous discussions, there are different types of masks and they can be used correctly, or incorrectly. An N95 mask, or another type of respirator, does protect the wearer, and will provide complete protection when combined with eye protection. To be effective, however, such a respirator mask must fit snugly on the face. It won’t work on a man with a beard. It won’t work on anyone, if it does not fit snugly, which means it has to be the appropriate size for your head and face. Some respirators, including some N95s, allow air and what’s in the air to be exhaled through valves; while such masks protect the wearer, they do not protect other people from the wearer, so they must be covered with second mask, such as a surgical mask. Also, if you have been exposed to people who are infected and shedding virus in droplets when they breathe, you can become infected in the process of removing your respirator mask, if you don’t remove it correctly, following procedures designed to prevent things from outside the mask from getting onto the T-zone of your face, or onto your fingers.
As for other face coverings, there are many factors coming into play that make it difficult to conduct clinical studies on the effectiveness of wearing a mask on protecting the wearer. The 3-layered masks are better than single layer masks at stopping the transmission of droplets in both directions, meaning from and to the wearer. Indeed, you always should wear at least a 3-layer mask. As for the question of whether wearing two ordinary 3-layer masks will decrease transmission of the virus throughout the community, as with many newly emerging issues related to this pandemic, there aren’t enough data yet. But that doesn’t mean that everybody shouldn’t double mask. To introduce my take on this, let’s review something else that we have discussed related to masks, namely that many people do not use masks correctly.
Not covering the nose not only looks ridiculous, but also allows the wearer to spread the virus from the nose, and puts him or her and greater risk of being infected by others. People will give you all kinds of creative excuses about why their masks are not covering the nose. “I was getting ready to put it over my nose”, “I was only halfway through the process of getting my mask on when you caught me with my nose uncovered”, “it keeps falling down” —there is no shortage of such lines and they are pitiful excuses. When you don your mask, the nose is the first thing that should get covered. Doing this allows you to position the mask in the first place, and if there is a bendable metal strip it allows you to shape that around the nose. There is no moment in the mask donning process when the mouth should be covered without the nose covered. Similarly, any mask that falls down from your nose, either is not one tight enough, or it was not placed high enough over the nose in the first place. Several times, I have asked random people to pull their masks over their noses, only to see them pull the masks up just barely enough to hide the nostrils. Then, 10 seconds later, it falls down again and is bobbing up and down as they speak. You don’t do that with your pants; don’t do it with your mask. You need to position the mask higher than just the lower edge of your nose, as high as you can get it without the mask interfering with your vision. Another issue is what you do with your mask when it is not covering your face, especially right after a situation in which the mask may have been hit with droplets containing the virus. If you enter a public place with people who are not masked, or not masked correctly, and if you are masked, and then you leave and squoosh down the mask on your chin, and then infected droplets get to the inside surface of the mask and then you recover your mouth and nose, you can get infected that way. To get the most out of a mask, you need to think about what the mask is doing and ways that you might get infected, and account for those possibilities.
With all of this in mind, here is my take on double masking, for the time being while there are no data on the benefit. If you are a good mask wearer —if you wear your masks correctly, if you think about how the masks work, how one type of mask works versus another kind, what’s going in and what’s going out— by all means, double mask. If you are the kind of person who washes hands correctly, if you intuitively use paper towels to turn off the faucet in a public restroom, then open the door with the paper towel, hold the door with your foot while throwing the paper towel into the trash basket to avoid touching the door, if you find creative ways to avoid touching the door after cleaning your hands when you find yourself in a public restroom that lacks accessible paper towels, the most likely you are the kind of person who can use two masks correctly. Doing so means that you will think things through in terms of what you touch and what you clean and in what order as you don and doff your two masks. But if you are not up to this, if you someone who simply goes through the motions when using one mask, you let the mask do things that can infect you or others, then double masking won’t help in your case, and may even do more harm. Take home lesson. First be an expert at using one mask, then you can delve into the issues of using two.