>> Welcome back everyone to Inside Infection Control, our video blog here at CDC's Project Firstline. I'm Abby Carlson. I'm an infectious diseases doctor at the CDC, and it's great to have you here today. We talked in another video about your N95 respirator and what it does. And we also talked about how important it is that you get a fit test to make sure that your respirator fits securely and snugly against your face. However, after you've been fit tested and you're using your respirator at work, how do you check to make sure that your respirator is fitting well in that time and able to do its job of protecting you from particles and droplets in the air. So we're going to talk about what technique you can use. Every time you put on your N95, it's good to do something called a user seal check to make sure you have a good seal each time you use it. Why? Well, it's possible to put on your N95 and not have a good fit around all the edges of the respirator even if you do all the steps correctly. And you want a good seal so that the air you're breathing passes through the filtering material of the N95. If there's a leak or a bad seal, then it's likely that you're going to breathe in air that hasn't gone through that filtering material and so it's unfiltered through the sides and that's not what we want. We want to protect you from infection by having you only breathe filtered air. This is also why some facial hair can be a problem. If you have facial hair that sits where your respirator needs to seal to your face, it's going to create small leaks around the edges. You should be able to do a user seal check every time because even when you're fit tested, the respirator can get dirty or damaged and the straps can loosen up or other things can happen to make the seal not as tight over time. Also, a lot of us are having to use our N95s more than once or for longer periods because of the shortages and those N95s can simply wear out. And finally, your face might change. You might gain weight or lose weight or just find that the fit doesn't work anymore and that's why we fit test every year but also why a user seal check is good. The company that makes your N95 is going to have specific instructions on how to do a user seal check for your type of N95. So what we're going to talk about today is general guidance, and I'm going to model that with my N95 which I used in the hospital which is a little worn out now but good for talking about the user seal check. You should always follow the instructions for your specific type or ask your supervisor how to find them. Most of the time, the best way to check your seal is with something we call a positive pressure check. And all that means is that you're breathing out gently while blocking the filter where the air is usually going to make sure that there aren't any leaks around your face or in the filter itself. ^M00:03:19 Here's how it works. You put on your N95. And I'm not going to do that just so that you can hear me and you can see what's going on but that process of putting your N95 on, which we call donning, is the first step in making sure the seal is correct. And we've put some links in the comments to show you the videos that show how to put it on correctly. Once it's on, you're going to put your hands lightly over the surface of your N95 just like that. Okay. And you actually want to be blocking off the filter. You cover as much of the area as you can. Don't press down on your face too hard or anything like that, just cover as much of the area as you can. And then you breathe out gently. So you have it over and you breathe out. And you'll feel pressure if it's working correctly as the air you're breathing out builds up in this little space on the inside of your N95. If there is a leak, you're going to possibly hear it or see it if you're wearing glasses and they fog up or your face shield fogs up or you'll feel it around the edges where your hands are holding things. If the pressure doesn't build up or if you feel that leak, what do you do? Well, if the air is leaking around your nose right here at the top part, you take the metal band that's usually found at the top of these respirators, and you try to mold it to your nose just kind of like clay. It's important to use both hands and to start from the top. You can imagine if you just use one hand and push like I'm doing now. You tent or push up the top and air is going to come leaking out off of the top of this respirator like this and so that doesn't work so much to just use one hand and mold. You've got to start from the top and push both hands down around your nose. That way you can form it right to your nose on the inside. Okay. You can also readjust these straps. Now you can see on mine, and your N95 should be the same, you can't actually make them longer or shorter. That's just a staple right there, but what you can do is move them up and down on your head and that moving up and down might allow it to just pull a little bit tighter against your face and seal off some of the small leaks. A couple things to remember when you do that, don't put the straps behind your ears or right across the ears like this because that is not going to hold it as well and also don't cross the straps. If those things don't work and you still have a leak, you might just need a different type of respirator or you might need a new respirator because yours is worn out. So try a new respirator. If that doesn't work, talk to your fit testing folks about getting fit tested for a new design and see what you can do with them to find a respirator that works for you. To sum it up, a user seal check is important each time to make sure your N95 is doing its job of getting all that air through the filter material every time you put it on. Our comment section is going to have some links to some more information about N95s, fit testing, how to do a user seal check, some videos that you can take a look and resources that our colleagues at NIOSH have put together. So make sure you take a look at that to get a good seal for your N95. Thanks as always for joining us. Be sure to follow us up on Facebook and Twitter and at cdc.gov/projectfirstline, our website. We will see you back with the next episode.