Stuff You Should Know

Reusing Masks

It can be hard to keep finding fresh N95 masks, even if you have an awesome local mask distro helping out. Here’s how you can make them last.


1. When should I throw out my N95?

An N95 mask expert says:

  • You should replace your mask after 30-40 hours of wear time even if none of the above replacement conditions have occurred.


  • How Long Can I keep Wearing the Same Respirator Mask? (NY Times, 2022)
  • Extended use or reuse of N95 respirators during COVID-19 pandemic: An overview of national regulatory authority recommendations (National Library of Medicine, 2020)
  • Post referencing this study: “Stability of Aerosolized SARS-CoV-2 on Masks and Transfer to Skin”

2. What if it gets wet?

If it’s anything less than soaked, you’re probably fine. Just let it dry out thoroughly before the next use.


3. Can I clean it?

Not with home equipment, sad to say. Your best bet is to let it self-sterilize by resting for 24-48 hours in a paper bag. That way, it can dry out but it can’t get dirty. Keep masks separate so they don’t cross-contaminate. Using alcohol or detergents will destroy the electrostatic charge that makes it work. 

Other Resources

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