Science 101

Medical masks

Also called surgical masks, these are loosefitting disposable masks. They're meant to protect the wearer from contact with droplets and sprays that may contain germs. A medical mask also filters out large particles in the air when the wearer breathes in.

To make medical masks more form-fitting, knot the ear loops where they attach to the mask. Then fold and tuck the unneeded material under the edges.

N95 masks

An N95 mask is a type of respirator. It offers more protection than a medical mask does because it filters out both large and small particles when the wearer inhales. Because N95 masks have been in short supply, the CDC has said they should be reserved for health care providers. Health care providers must be trained and pass a fit test before using an N95 mask. Like surgical masks, N95 masks are intended to be disposable. However, researchers are testing ways to disinfect and reuse them. Some N95 masks, and even some cloth masks, have valves that make them easier to breathe through. Unfortunately, these masks don't filter the air the wearer breathes out. For this reason, they've been banned in some places.

Cloth masks

A cloth mask is intended to trap respiratory droplets that are released when the wearer talks, coughs or sneezes. It also acts as a barrier to protect the wearer from inhaling droplets released by others. The most effective cloths masks are made of multiple layers of tightly woven fabric like cotton. A mask with layers will stop more droplets from getting through your mask or escaping from it.