Masks and Respiratory Viruses Prevention

An additional strategy to further protect yourself and others

How it works

Generally, masks can help act as a filter to reduce the number of germs you breathe in or out. Their effectiveness can vary against different viruses, for example, based on the size of the virus. When worn by a person who has a virus, masks can reduce the chances they spread it to others. Masks can also protect wearers from inhaling germs; this type of protection typically comes from better fitting masks (for example, N95 or KN95 respirators).

There are many different types of masks that have varying abilities to block viruses depending on their design and how well they fit against your face. Cloth masks generally offer lower levels of protection to wearers, surgical/disposable masks usually offer more protection, international filtering facepiece respirators (like KN95 respirators) offer even more, and the most protective respirators are NIOSH Approved® filtering facepiece respirators (like N95® respirators).

Steps you can take

Individuals can

• When choosing to wear a mask, choose the most protective type you can. Determine how well it fits. Gaps can let air leak in and out. Check for gaps by cupping your hands around the outside edges of the mask. If the mask has a good fit, you will feel warm air come through the front of the mask and may be able to see the mask material move in and out with each breath.

• Learn about proper technique for wearing an N95 respirator.

Organizations can

• Provide free, high-quality masks to your workforce or visitors in times of higher respiratory viral spread.

Key times for prevention

All of the prevention strategies described in this guidance can be helpful to reduce risk. They are especially helpful when:

• Respiratory viruses are causing a lot of illness in your community.
• You or the people around you were recently exposed to a respiratory virus, are sick, or are recovering
• You or the people around you have risk factors for severe illness.