COVID-19 spreads when an infected person breathes out droplets and very small particles that contain the virus. These droplets and particles can then be breathed in by other people or land on their eyes, noses, or mouth.
Know which masks provide the best protection against COVID-19.
Well-fitting respirators such as:
Choose a mask:
RESPIRATORS (such as N95, KN95, and KF94)
Respirators are specialized masks that are designed to filter out very small particles, including the virus that causes COVID-19. There are many types of respirators.
Respirators that fit well and provide a tight seal on your face protect you better than a cloth mask or a medical mask. They may be less comfortable because they filter better and fit more tightly.
For more detailed information, see CDC Respirators.
Also called surgical, medical procedure, disposable procedure, or dental masks. These include various types of loose-fitting disposable masks.
Note: Some disposable masks are designed and tested to demonstrate that they perform to certain standards. These include the American Society for Testing and Materials (ASTM) standards F2100 or F3502. The most protective masks have a particle filtration efficiency of at least 95%. Look for masks that have been tested by an accredited third-party laboratory.
Cloth masks (also called reusable masks) work best if they are tight fitting and are made of certain materials that filter out small particles.
For better protection, wear a cloth mask OVER a medical mask (see Double masking).
Note: Some cloth masks are designed and tested to demonstrate that they perform at a consistent level. The American Society for Testing and Materials (ASTM) has set a standard (ASTM F3502) for barrier face coverings, including cloth ("reusable") masks. Masks rated as ASTM F3502-Level 2 for particle filtration provide better protection than Level 1. The most protective masks have a particle filtration efficiency of at least 95%. If you are considering purchasing a cloth mask that is not ASTM rated, look for one that has been tested by an accredited third-party laboratory. Ratings for some commercially available face masks are published on the CDC website Barrier Face Coverings and Workplace Performance/Performance Plus Masks.
Tips to check that your mask fits
Wearing two masks or “double masking”
“Double masking” is when a well-fitting cloth mask is worn on top of a medical mask. This makes the medical mask fit better and adds extra layer(s) of protection.
The following people should not wear a mask:
Note: Underlying medical conditions
Most people with underlying medical conditions, including those with asthma, can wear a mask, unless instructed not to by their doctor. Wearing a mask does not reduce a person’s oxygen supply or cause a build-up of carbon dioxide. If you or someone you care for has an underlying health condition and you have concerns about wearing a mask, talk to your doctor.
Clear masks or masks with a clear plastic panel are an alternative type of mask for people who are or who interact with:
CDC and CA State mask guidance websites