How to choose and use a mask: when it still helps
Masks are one layer of risk reduction. Their benefit depends on the setting, fit and the needs of people nearby.
Use masks where risk is higher
Masks can be particularly useful in crowded, enclosed or poorly ventilated places, in healthcare settings, around people at higher risk, or when you have respiratory symptoms.
Fit matters
Choose a mask that covers the nose, mouth and chin and has minimal gaps around the face. A better-filtering mask only offers its potential benefit when it fits closely enough to reduce leakage.
Use it with other measures
Masks complement ventilation, staying home when ill, testing when appropriate and vaccination. Supporting a person who chooses to wear a mask helps protect everyone.
Sources
Related guides
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Masks and ventilation: practical layers for reducing respiratory virus risk
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This content is general information, not a diagnosis or individual medical advice. Seek urgent help for severe or rapidly worsening symptoms.