CDC
What you need to know
When you wear a mask, you protect others as well as yourself. Masks work best when everyone wears one.
A mask is NOT a substitute for social distancing. Masks should still be worn in addition to staying at least 6 feet apart, especially when indoors around people who don’t live in your household.
Masks should completely cover the nose and mouth and fit snugly against the sides of face without gaps.
Masks should be worn any time you are traveling on a plane, bus, train, or other form of public transportation traveling into, within, or out of the United States and in U.S. transportation hubs such as airports and stations.
People age 2 and older should wear masks in public settings and when around people who don’t live in their household.
Wear a mask inside your home if someone you live with is sick with symptoms of COVID-19 or has tested positive for COVID-19.
Wash your hands with soap and water for at least 20 seconds or use hand sanitizer with at least 60% alcohol after touching or removing your mask.
Masks may not be necessary when you are outside by yourself away from others, or with people who live in your household. However, some areas may have mask mandates while out in public, so please check the rules in your local area (such as in your city, county, or state). Additionally, check whether any federal mask mandates apply to where you will be going.
CDC continues to study the effectiveness of different types of masks and update our recommendations as new scientific evidence becomes available. The most recent scientific brief is available here: Scientific Brief: Community Use of Cloth Masks to Control the Spread of SARS-CoV-2 | CDC
CDC recently conducted a study in a laboratory that tested the performance of different mask combinations.
There are several easy methods to improve the performance of your mask. Visit CDC’s Improve the Fit and Filtration of Your Mask to Reduce the Spread of COVID-19 webpage to learn more.
Evidence for Effectiveness of Masks
Your mask helps protect those around you
COVID-19 spreads mainly from person to person through respiratory droplets. Respiratory droplets travel into the air when you cough, sneeze, talk, shout, or sing. These droplets can then land in the mouths or noses of people who are near you or they may breathe these droplets in.
Masks are a simple barrier to help prevent your respiratory droplets from reaching others. Studies show that masks reduce the spray of droplets when worn over the nose and mouth.
You should wear a mask, even if you do not feel sick. This is because several studies have found that people with COVID-19 who never develop symptoms (asymptomatic) and those who are not yet showing symptoms (pre-symptomatic) can still spread the virus to other people. Wearing a mask helps protect those around you, in case you are infected but not showing symptoms.
It is especially important to wear a mask when you are indoors with people you do not live with and when you are unable to stay at least 6 feet apart since COVID-19 spreads mainly among people who are in close contact with one another.
Your mask offers some protection to you
A cloth mask also offers some protection to you too. How well it protects you from breathing in the virus likely depends on the fabrics used and how your mask is made (such as the type of fabric, the number of layers of fabric, and how well the mask fits). CDC is currently studying these factors.
Who should or should not wear a mask
Masks should be worn:
By people 2 years of age and older
Any time you are in a public setting
Any time you are traveling on a plane, bus, train, or other form of public transportation traveling into, within, or out of the United States and in U.S. transportation hubs such as airports and stations
When you are around people who do not live with you, including inside your home or inside someone else’s home
Inside your home if someone you live with is sick with symptoms of COVID-19 or has tested positive for COVID-19
CDC recognizes there are specific instances when wearing a mask may not be feasible. In these instances, consider adaptations and alternatives.
The following categories of people are exempt from the requirement to wear a mask:
A child under the age of 2 years;
A person with a disability who cannot wear a mask, or cannot safely wear a mask, for reasons related to the disability;
A person for whom wearing a mask would create a risk to workplace health, safety, or job duty as determined by the workplace risk assessmentexternal icon.
Types of masks
Some masks work better than others to help slow the spread of the virus that causes COVID-19. Note: N95 respirators approved by CDC’s National Institute for Occupational Safety and Health (NIOSH) should be prioritized for healthcare personnel.
Cloth masks
More effective fabrics for cloth masks are
Tightly woven fabrics, such as cotton and cotton blends
Breathable
Two or three fabric layers
Less effective fabrics for cloth masks are
Loosely woven fabrics, such as loose knit fabrics
Single layer
CDC is currently studying the effectiveness of various cloth mask materials. Refer to our Scientific Brief: Community Use of Cloth Masks to Control the Spread of SARS-CoV-2 | CDC for more information.
Medical procedure masks (sometimes referred to as Surgical Masks or Disposable Face Masks)
Medical procedure masks are single-use masks that are not made of cloth and are not designed to be washed or laundered. They are sold online and through large retail stores. These are not the same as other medical masks.
You may prefer using medical procedure masks in situations where your mask is likely to get wet or dirty. As with cloth masks, make sure your medical procedure mask fits close to your face without large side gaps and completely covers your nose and mouth. Bring extra medical procedure masks with you in case you need to change out a dirty or wet mask.
Masks with exhalation valves or vents
CDC does not recommend using masks with exhalation valves or vents. The hole in the material may allow your respiratory droplets to escape and reach others. Research on the effectiveness of these types of masks is ongoing.
NIOSH-approved N95 respirators
N95 respirators are critical supplies that should be prioritized for healthcare workers and other medical first responders to prevent supply shortages.
Clear masks or cloth masks with a clear plastic panel
Clear masks or cloth masks with a clear plastic panel are an alternative type of mask for people who interact with
People who are deaf or hard of hearing
Young children or students learning to read
Students learning a new language
People with disabilities
People who need to see the proper shape of the mouth for making appropriate vowel sounds (for example, when singing)
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If you use this type of mask, make sure
You can breathe easily
Excess moisture does not collect on the inside of the mask
You remove the mask before sleeping, since the plastic part could form a seal around your mouth and nose and make it hard to breathe
The FDA recently approved a transparent pdf icon[186 KB, 3 Pages]external icon medical mask. These transparent medical masks should be reserved for use by healthcare workers and patients who require them. There are several easy methods to improve the performance of your mask. Visit CDC’s Improve the Fit and Filtration of Your Mask to Reduce the Spread of COVID-19 webpage to learn more. You can also learn more by reading about a CDC study conducted in a laboratory that tested the performance of different mask combinations. Top of Page
Other Types of Face Protection
CDC does not recommendexternal icon using face shields or goggles as a substitute for masks. Goggles or other eye protection may be used in addition to a mask. Do NOT put a plastic face shield (or a mask) on newborns or infants.
Face shields and goggles are primarily used to protect the eyes of the person wearing it. Goggles do not cover the nose and mouth. Face shields are not as effective at protecting you or the people around you from respiratory droplets. Face shields have large gaps below and alongside the face, where your respiratory droplets may escape and reach others around you and will not protect you from respiratory droplets from others. However, wearing a mask may not be feasible in every situation for some people.
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Face shields and goggles
For example, people who interact with those who are deaf or hearing impaired may find that a face shield is better than a mask when communicating. If you must wear a face shield instead of a mask:
Choose a face shield that wraps around the sides of your face and extends below your chin or a hooded face shield. This is based on the limited available data that suggest these types of face shields are better at preventing spray of respiratory droplets.
Wash your hands after removing the face shield. Avoid touching your eyes, nose, and mouth when removing it.
Clean and disinfect reusable face shields according to the manufacturer’s instructions or by following CDC face shield cleaning instructions. If you use a disposable face shield, wear it once and throw it away according to the manufacturer’s instructions.
Mask adaptations and alternatives
CDC recognizes that wearing masks may not be possible in every situation or for some people. Those who cannot wear a mask are urged to prioritize virtual engagement when possible. For in-person activities, we have provided a few examples of what you can do to make wearing a mask more feasible and how to reduce the spread of COVID-19 if you cannot wear a mask.
Situations where wearing a mask may not be possible
Make sure to maintain physical distance from others when you cannot wear a mask.
Dining
CDC recommends wearing a mask while dining in a restaurant, particularly indoors and when speaking with restaurant workers and servers, except when actively eating or drinking. The risk of COVID-19 spread increases in a restaurant or bar setting as interactions within 6 feet of others increase. Masks may reduce the risk of COVID-19 spread when worn in any of these risk scenarios.
Water activities
Do not wear a mask when doing activities that may get your mask wet, like swimming at the beach or pool. A wet mask can make it difficult to breathe and may not work as well when wet.
High intensity activities
Masks should always be used in public settings, but if you are unable to wear a mask because of difficulty breathing during high intensity activities, choose a location with greater ventilation and air exchange (for instance, outdoors versus indoors) and where you can keep at least 6 feet of distance from others during the activity. If such a location is not available, opt for low-intensity activities such as walking or yoga that allow for mask wearing.
If you are able to wear a mask, remove your mask if it gets moist from sweat and replace it with a clean mask.
Opt for an activity that does not require using mouth guards or helmets. Wearing a mask with these types of protective equipment is not safe if it makes it hard to breathe.
Supervise children who are wearing a mask while playing sports.
Certain groups of people who may find it difficult to wear a mask
Some children 2 years and older, and people of any age with certain disabilities
Appropriate and consistent use of masks may be challenging for some children and for people of any age with certain disabilities, including people who have high sensitivity to materials on their faces, difficulty understanding why wearing a mask is protective (such as those with an intellectual disability), or those who have problems controlling their behavior.
When determining if children and people with certain disabilities should wear a mask, assess their ability to:
Use a mask correctly
Avoid frequent touching of the mask and their face
Limit sucking, drooling, or having excess saliva on the mask
Remove the mask without assistance
Those caring for children and people with certain disabilities who may need assistance with wearing masks should
Ask their healthcare provider for advice about the person you are caring for wearing a mask. If they are unable to wear a mask, ask their healthcare provider about alternative ways of reducing transmission risk
Ensure proper mask size and fit
Remove their mask before sleeping, napping, when they may fall asleep (such as in a car seat or stroller), and in situations when continual supervision is not possible
Consider prioritizing wearing a mask in public settings and when around people who don’t live in your household, particularly when indoors. Masks may not be necessary when you and the person you are caring for are outside and away from others, or with other people who live in the same household. However, some localities may have mask mandates while out in public and these mandates should always be followed.
Masks should not be worn by:
Child under 2 years of age
A person with a disability who cannot wear a mask, or cannot safely wear a mask, for reasons related to the disability
A person for whom wearing a mask would create a risk to workplace health, safety, or job duty as determined by the workplace risk assessmentexternal icon
People who are deaf or hard of hearing, and those who will interact with people who are hearing impaired
If you interact with people who rely on reading lips, you may have difficulty communicating while wearing a mask.
Consider wearing a clear mask or a cloth mask with a clear panel
If you are not able to get a clear mask, consider using written communication, closed captioning, or decreasing background noise to make communication possible while wearing a mask that blocks lips
People with certain underlying medical conditions
Most people with underlying medical conditions can and should wear masks.
If you have respiratory conditions and are concerned about wearing a mask safely, discuss with your healthcare provider the benefits and potential risks of wearing a mask.
If you have asthma, you can wear a mask. Discuss with your healthcare provider if you have any concerns about wearing a mask.
Outdoor workers
If you work in a setting where masks could increase the risk of heat-related illness or cause safety concerns (for example, straps getting caught in machinery):
Discuss with an occupational safety and health professional what mask would be suitable.
Prioritize wearing masks indoors and when in close contact with other people, like during group travel or shift meetings. Some localities may require wearing masks in public while outdoors, and these requirements should be followed.
In cold weather, wear masks under winter gear such as scarves and ski masks. If masks become wet from breathing or snow, replace them with dry ones. Keep one or more backups for this purpose.
What to do if you find wearing a mask uncomfortable?
It may help to practice wearing a mask at home for short periods to get used to the feeling and try different styles and fabrics recommended above.
Try relaxation techniques such as breathing in and out deeply or listening to soothing music while wearing a face mask, which can help to keep you calm.
Mask use and carbon dioxide
Wearing a mask does not raise the carbon dioxide (CO2) level in the air you breathe
A cloth mask does not provide an airtight fit across the face. The CO2 completely escapes into the air through the cloth mask when you breathe out or talk. CO2 molecules are small enough to easily pass through any cloth mask material. In contrast, the respiratory droplets that carry the virus that causes COVID-19 are much larger than CO2, so they cannot pass as easily through a properly designed and properly worn cloth mask.
Cold Weather
In cold weather, masks may become wet from breathing, snow, or other precipitation. Change a mask when it becomes wet. A wet mask is harder to breathe through, is less efficient at preventing your respiratory droplets from reaching others, and allows for more respiratory droplets to escape around the edges of the mask. It is especially important to have one or more replacement masks during cold weather. If your reusable mask becomes wet, put it in a sealed plastic bag until you can wash it.
Scarves and other headwear such as ski masks and balaclavas used for warmth are usually made of loosely knit fabrics that are not suitable for use as masks to prevent COVID-19 transmission. They can be worn over a mask.
If you wear glasses, find a mask that fits closely over your nose or has a nose wire to help reduce fogging. Consider using an antifogging spray that is made for eyeglasses.
People with beards
Certain types of facial hair, like beards, can make mask fitting difficult. People with beards can
Shave their beards.
Trim their beards close to the face.
Use a mask fitter or brace.
Wear one disposable mask underneath a cloth mask that has multiple layers of fabric. The second mask should push the edges of the inner mask snugly against the face and beard.
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References
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https://www.cdc.gov/coronavirus/2019-ncov/prevent-getting-sick/cloth-face-cover-guidance.html
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