What types of masks should we wear?

Masks with good filtration capability are recommended. These include reusable masks that are made of at least 2 layers of fabrics, and surgical masks. Single-use masks would typically report their filtration efficiency* as part of their product specifications.

A mask should be worn such that it closely and completely covers the nose and mouth, with the mask touching the cheeks and chin (i.e. without leaving a gap between the mask and the face).

Masks with exhalation valves (usually visible as a raised disc on the front or side of the mask), have a decreased effect of preventing the release of droplets from the wearer during exhalation, even if it does provide protection against disease transmission to the wearer. The public, especially those who are unwell with respiratory symptoms (e.g. cough, runny nose), should not wear masks with valves as they may expose others to the risk of infection from droplets released through the valve.

* Bacterial filtration efficiency is a measure of the degree of barrier protection provided by a material or fabric. This is often indicated on the packaging or product description of masks being sold.