A N95 mask (respirator) is a safety device that covers the nose and mouth and helps protect the wearer from breathing in some hazardous substances. An N95 mask protects you from breathing in small particles in the air such as dust and mold. One important addition to your respiratory protection plan should be reuse of N95 respirators during a shortage. The OSHA directive indicates that a respirator can be reused as long as it \”maintains its structural and functional integrity and the filter material is not physically damaged or soiled.\”

How do N95’s work?

The filtration media contained in the N95 is designed to capture at least 95% of particles measuring a median of 0.3 µm. Even though viral particles are a few orders of magnitude smaller than this, nanoparticles mainly travel by Brownian motion and are effectively captured within the N95 filter via mechanical and electrostatic forces. The outer mask material is typically hydrophobic polypropylene. Importantly, extended use, re-use, or re-processing of masks all affect the filtration capacity of the mask.

What are my options for extending the life of my N95 mask?

It is important to differentiate between extended use, re-use, and mask re-processing.
Extended use

The CDC reports that prolonged N95 mask use (including between patients) can be safe for up to 8 hours, and encourages each user to review each manufacturer’s recommendations prior to following this strategy. Current guidelines encourage wearing a face shield over the N95 to decrease the chances of soiling the mask.
Re-use

Because coronaviruses lose their viability significantly after 72 hours, many organizations have promoted a rotation and re-use strategy. Assuming there is no soiling and minimal to no viral contamination to the mask, the CDC suggests that masks can be re-used up to 5 times .