When and Why to Wear a Mask
The Benefits of Masking and Tips for Choosing the Right Mask
Wearing a high-quality mask that fits well and has good filtration helps to protect you from breathing in viruses, wildfire smoke, and other particles or germs in the air.
Respirators, such as N95s, KN95s, or KF94s, are the best type of masks. They offer more protection because they generally have better fit and filtration. Other masks such as surgical masks and cloth face coverings, tend to be looser and not as protective as respirator masks. N95, KF94 and KN95 respirators can be purchased at drugstores, hardware supply stores, and online.
Mask wearing may be an especially good precaution for anyone who is at higher risk for getting very sick from respiratory illnesses, has a history of breathing/lung issues, or has environmental exposures. ā
āWhen to Consider Wearing a Mask
Protection Against Respiratory Virusesā
If you believe you were exposed and will be in contact with someone who is higher risk, consider wearing a high-quality mask.
If you are at higher-risk of becoming severely ill, consider wearing a high-quality mask (respirator) when you are in an indoor public setting with poor ventilation, or when you areāÆtraveling on public transportation.
People who are at higher risk for severe respiratory infections include:
Older adults (aged 50 years and older)
People with certain medical conditions such as a chronic disease or cancer
People with weakened immune systems
People who are pregnant or were recently pregnant
People with disabilities
People who live in congregate care facilities, such as a skilled nursing facility
Children under 5, with greatest risk in infantsā
Protection Against Harmful Environmental Exposures
Below are a few examples of when masks are highly recommended during an environmental exposure. ā
Wildfire Smoke
When aāÆwildfire, wildfire smoke, orāÆpoor air qualityāÆis in your area, wearing an N95 respirator can help filter out harmful smoke particles, if you must go outside. When fitted correctly, an N95 respirator that fits over the nose and mouth can significantly reduce breathing in harmful particles. ā
Valley Fever
InāÆcertain areas of California, the fungus that causes Valley fever grows in the soil and may be in outdoor dust. While working or spending time outdoors in dusty areas where Valley fever is common, wear a properly fitted mask approved by theāÆNational Institute for Occupational Safety and Health (NIOSH). A N95 or higher-level respirator, may help protect you from breathing in dust and fungal spores that can cause Valley fever. Learn more aboutāÆValley fever safety in the workplace and Valley fever prevention. ā
āChoosing the right maskā
āHigh Qualityā
N95s
N95 respirators offer the best protection. Adults should choose an N95 respirator approved by NIOSH. N95s have two head straps and a tight fit. Authentic NIOSH-approvedāÆN95 respirators should have specific markings. Learn more about counterfeit (fake) respirator masks and how to use N95 respirators.āÆ āāā
KN95s and KF94s
KN95s and KF94s are respirators that meet international standards. They provide good protection, but less protection than N95s. Most KN95s and KF94s have ear loops, which may provide a less-snug fit than respirators with head straps such as N95s.
If you choose to use a KN95 or KF94, use one that has been tested by NIOSH and has a minimum "filtāration efficiency" of 95% or higher. While these respirators have been tested by NIOSH, they are not designed and approved according to NIOSH standards.ā
Surgical Masks
Surgical masks include various types of loose-fitting disposable masks. These masks can block large droplets but donāt fit close to the face. Even when worn tightly against your face, surgical masks provide much less protection than a well-fitting respirator. ā
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Cloth Masks
Cloth masks are less protective than surgical masks or high-quality respirators. ā
Fit
AāÆmask should fit snuglyāÆto your face, covering both your nose and mouth, with no gaps between the mask and your skin. If your mask has any gaps, it will allow the flow of unfiltered air into your lungs. Also, any facial hair will prevent the mask from working properly. Maintain a cleanāÆshaveāÆ(PDF), if possible.
Check for any gapsāāÆby cupping your hands around the outside edges of the mask. Make sure no air is flowing from the area near your eyes or from the sides of the mask. If the mask has a good fit, you will feel warm air come through the front of āthe mask and may be able to see the mask material move in and out with each breath.
Change your mask as needed. Do not wear a dirty mask. Throw away disposable masks or respirators that become wet or dirty.ā
āāāFor Chāildren
Masks canāÆbe worn safely by childrenāÆ2 years of age and older. There are rare exceptions. Children under age 2 should not wear a mask. Choose a mask for your child that has the best protection,āÆbest fit, and one your child will wear.
āMasks should fitāÆover the nose and under the chin with no gaps around the edges. They should not prevent your child from seeing. KN95s and KF94s are both available in āchildā or āextra-smallā sizes. N95s in size āsmallā may fit older children but may not fit younger or smaller children. There are noāÆNIOSH-approved N95 masks for childrenāÆat this time.
Who Shāould NOT Wear a Maskā
Wearing a mask may be difficult for people with sensory, cognitive, or behavioral issues. Masks are not recommended for children under 2 years of age. They are also not recommended for persons who have trouble breathing or are unconscious, incapacitated or otherwise unable to remove the mask without help. Mask wearing can also be hard for people who are hearing impaired or are communicating with a person who is hearing impaired because seeing the mouth may be needed to communicate. ā
Other Considerations
Any person who chooses to wear a mask cannot be excluded from participating in an activity or entering a venue or business (including schools or childcare) unless wearing a mask would pose a safety hazard. ā
This information is intended for a general audience. Some workplacesāāÆ(PDF), local health departments, and Cal/OSHA may have additional recommendations or requirements for wearing a mask. āā