How to wear a face mask for maximum protection

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Nearly a year into the pandemic, we’ve accumulated a lot of information from scientists about the most effective face masks for protecting ourselves and others from COVID-19. But it doesn’t matter what kind of mask you’re using if you’re not wearing it properly.

Make sure you find the right size

The critically important first step when buying (or making) a mask is proper sizing. The key measurements to consider are ear-to-ear over the nose, nose-to-chin, and the length of the mask’s ear loops. If the adult mask you want comes in a size you know will be too large for your face, consider a kid-sized option.

Ensuring your mask isn’t too big from the outset will help you avoid having to constantly pull your mask back up over your nose and prevent gaps from forming at the sides and bottom. On the flip side, a mask that’s too small will pop off your nose as soon as you start talking. Once you’ve found something that generally works for you, it’s time to think about fine-tuning the fit.

Full coverage is crucial

When you first put your mask on, make sure it covers both your mouth and your nose. Failing to cover both renders even a high-quality mask basically useless, since you can still exhale viral particles from your nostrils if they’re not underneath the mask.

Small adjustments will keep your mask in place

You’ll probably have to make some additional tweaks to ensure a proper fit. The most important one will be to eliminate any gaps between your skin and the mask. Minimizing the cracks through which the virus can slip will help keep any particles you exhale contained within the mask and also reduce the likelihood that any virus floating around outside your mask will get into your mouth or nose.

[Related: Learn three easy ways to wash reusable cloth masks.]

First, place your fingers where your mask meets the bridge of your nose and run them along the upper edge of your mask to make sure it’s pressed flat against the curve of your nose and over the tops of your cheekbones. Having a mask with a moldable nose piece ensures you won’t have to fiddle with this seal throughout the day. A tight fit here is also key for preventing fogged-up glasses.

Next, check if the sides of the mask are bulging out from your cheeks. If they’re laying flat, you’re good to go. If not, try tightening the ear loops until the gap disappears or is as small as possible. Some masks have built-in adjusters that you can slide toward and away from your ears to find the perfect fit. If you’re using a disposable mask or one without adjustable straps, consider tying a small knot at the midpoint of each loop. This will also minimize any down-the-nose slippage and keep the entire mask in place.

Don’t take the easy road and twist the ear loops to make the straps shorter, since this will pinch the top and bottom corners of each side together and make the side-gap even larger.

Finally, check to make sure that the bottom of your mask is hugging the curve of your chin. Similar to gaps at the top and sides of the mask, a space at the bottom provides an opening for particles to flow in and out. If the fabric is folding or protruding at weird angles and adjusting the ear loops isn’t fixing the problem, try a different shape or style of mask that may be better suited to the shape of your face.

Ideally, your mask should fit comfortably enough that you aren’t tempted to fidget with it and snugly enough that it stays in place for long periods of time. If you do have to readjust your mask while out and about, make sure you wash your hands or at least use hand sanitizer before you touch the outside of your mask. Even with clean hands, avoid grabbing the middle section of your mask that lays over your nose and mouth; doing so may contaminate the mask and reduce its effectiveness. Instead, pinch the edges of the mask with your fingers to reposition it.