- Acquiring respiratory protection for doctors and other health care workers has become a major challenge of the COVID-19 pandemic.
- This major challenge resulted in nonstandard practices such as the use of expired respirators and various sterilization processes to extend the useful life of respirators in health care settings.
- Due to the limited supply of respirators, non-approved respirators have been donated or acquired by hospitals as a potential replacement for approved N95 respirators.
- The study aimed to assess the filtration efficiencies for face mask alternatives used during the COVID-19 pandemic.
- This quality-improvement study was conducted between April and June 2020.
- The study used the Occupational Safety and Health Administration’s Quantitative Fit Testing Protocol for Filtering Facepiece Respirators in a laboratory atmosphere supplemented with sodium chloride particles to assess the filtration efficiencies of a variety of respirators worn by a male volunteer and female volunteer.
- The result shows expired N95 respirators with intact elastic straps and respirators subjected to ethylene oxide and hydrogen peroxide sterilization had the same filtration efficiencies.
- The performance of N95 respirators in the wrong size had slightly decreased performance.
- 6 of the respirators not listed as approved in this evaluation failed to achieve 95% fitted filtration efficiencies.
- 2 imported respirators authorized for use by the Centers for Disease Control and Prevention that were not NIOSH-approved tested in this study did not achieved 95% fitted filtration efficiencies.
- Surgical and procedural face masks had filtering performance that was lower relative to that of N95 respirators.
- The study concluded that expired N95 respirators and sterilized, used N95 respirators can be used when new N95 respirators are not available, and that other alternatives may provide less effective filtration.
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