Coronavirus (COVID-19): masks

When to wear a mask and how to choose a mask to help prevent the spread of COVID-19.

Wearing a mask can help prevent the spread of COVID-19. You should wear a mask in indoor public places, public transportation and crowded outdoor spaces.

Wearing a mask

To protect yourself and others, Public Health recommends that you should wear a mask in indoor public places, public transportation and crowded outdoor spaces.

Wearing a mask can help prevent the spread of COVID-19. How well a mask works depends on the materials used and how well it fits.

Wearing only a face shield is not recommended. Face shields protect your eyes and can be worn in addition to a mask. Using a face shield alone doesn’t protect you or other people from infectious respiratory particles that can escape around the face shield.

Masks with exhalation valves are not recommended because they don't protect others from COVID-19 and don't help prevent the spread of the virus.

Choosing a mask and proper fit

A non-medical mask should:

  • be made of at least 3 layers, including
    • at least 2 layers of tightly woven fabric, like cotton
    • a middle layer of filter-type fabric, like a non-woven polypropylene
  • use materials that are breathable

When choosing a mask, proper fit is very important. A well-fitting mask should:

  • allow for easy breathing
  • fit securely to the head with ties or ear loops
  • maintain its shape after washing and drying
  • be comfortable and not require frequent adjustments
  • be made of tightly woven material fabric (like cotton or linen)
  • be large enough to completely and comfortably cover the nose, mouth and chin without gaps

To make sure your mask fits close to your face without gaps, you should:

  • adjust ties or ear loops
  • adjust the flexible nose piece
  • wear a well-fitting cloth mask over a disposable mask
  • keep facial hair short, if possible

Learn more: how to make sure your mask fits properly.

Filters

You can add a filter to a non-medical mask by:

  • adding a filter-type fabric (like a non-woven polypropylene) as a middle layer
  • inserting a disposable filter into a pocket inside the mask (disposable filters should be removed from the mask before washing and changed as directed by the manufacturer)

Proper use

A mask is most effective when it’s worn properly. Uncovering your nose or mouth while wearing a mask:

  • exposes you and others to potentially infectious respiratory particles
  • won’t help prevent the spread of COVID-19

Wash your hands or use alcohol-based hand sanitizer when you:

  • adjust your mask
  • put your mask on
  • take your mask off

It's important to keep your mask clean when not in use, or when eating or drinking. Don’t hang the mask from your ears or place it under your chin.

Storing, cleaning and disposing a mask

Store your mask in a clean place until you need to wear it again. When your reusable mask becomes damp or dirty, wash it with hot, soapy water and let it dry completely before wearing it again. You can include a cloth mask with other laundry.

Damaged and disposable masks should be put in a regular garbage bin that’s lined with a plastic bag. When emptying the bin, take care to not touch used masks or tissues with your hands.

Medical masks

Medical masks are recommended for:

  • anyone who has tested positive for COVID-19 or has COVID-19 symptoms
  • people caring for someone who has tested positive for COVID-19 symptoms
  • people who live in an overcrowded setting with someone who has tested positive for COVID-19 or has COVID-19 symptoms
  • people who are at higher risk of more severe disease or complications from COVID-19
  • people who are at higher risk of exposure to COVID-19 because of their living situation

People who are not healthcare workers but are providing direct support (not necessarily direct care) in congregate settings should wear a medical mask during an outbreak or suspect outbreak.

Healthcare workers have occupational health and safety requirements related to mask use.

If you're not sure of your mask requirements, ask your employer.