N95 masks can be reused but should be disposed of under the following circumstances:

• after aerosol-generating contact with an infected person (such as coughing or sneezing)
• When the mask becomes contaminated with blood, respiratory or nasal secretions or other bodily fluids from an infected person.
• following close contact with or after leaving the care area of any patient infected with an infectious disease such as Covid-19.

Read: Can an N95 mask be reused?