More About Masks

We provide information on the various types of masks and when each should be used.

Barrier Masks

• Reusable; available in many different designs

• Stop outward projection as well as droplet inhalation, thereby protecting both wearers and those with whom they come in contact

• Do not create a complete seal and thus do not protect against inhalation of very small particles suspended in the air; however, such viral transmissions are thought to be rare in most settings

• Supplement the benefits of social distancing

• Recommended for use in the general community by healthy or asymptomatic individuals

• Few government standards apply 

 Medical Masks (or Surgical Masks)

Offer many of the same characteristics as barrier masks with the following differences:

• Single-use; often flat and rectangular with pleats; generally blue with white borders

• More effective than barrier masks, as they must meet government standards that include measuring their effectiveness at filtering 3-micron particles

• FFP1 masks (80% effectiveness) are sufficient for work in dusty environments

• FFP2 masks (95% effectiveness) are typically used by health-care personnel, as they protect both the health-care professional and the patient. But they do not fit tightly and therefore are not recommended for use during aerosol-generating procedures.

• FFP3 masks (99% effectiveness) protect against very fine particles such as asbestos. However, it can be difficult to breathe with FFP3 masks so they often have exhalation valves that render them less effective in protecting against transmission from the wearer.

Respiratory Protective Devices

• Generally circular or oval and seal tightly against the face; should be fitted to the individual’s face

• Designed for single use, but can be reused if proper precautions are taken

• Protect against splashes and sprays as well as inhalation of droplets and air particles

• Government standards based on level of effectiveness. For example, N95s filter out 95% of 0.3-micron particles and N98s filter out 98% of these particles

• More restrictive than a medical mask, which can make it difficult to wear for extended periods

• Not recommended by the CDC for use outside of a health-care setting

• Not to be confused with ventilators, which are devices designed to maintain artificial breathing or circulate fresh air. Respiratory protective devices are designed for use by health-care professionals during aerosol-generating procedures such as intubation, where there is significant risk of infection. They can be uncomfortable, however, and thus are not practical for everyday use.