When choosing a mask, look at how well it fits, how well it filters the air, and how many layers it has. Make sure your mask completely covers your nose and mouth and fits snugly against your face. Gaps can let air with respiratory droplets leak in and out around the edges of the mask. Pick a mask with layers to keep your respiratory droplets in and others’ out. A mask with layers will stop more respiratory droplets getting inside your mask or escaping from your mask if you are sick.
Whether or not two masks are better than one depends on the type and the fit of the mask you are using. It is not mandated that you wear two masks, however the CDC recommends that for a better fit and extra protection, one option is to wear a disposable mask underneath AND cloth mask on top. You can also combine a cloth mask with a fitter or brace.
Updated January 29, 2021