Can You Reuse an N95 Mask? Study Reveals Filtration Efficiency Impact

In healthcare settings, N95 respirators have become critical protective equipment, especially in high-risk scenarios. But with shortages often causing supply constraints, healthcare workers and others have had to consider reusing or extending the use of these masks. A recent study published in JAMA Network Open on October 29, 2024, explores the impact of reuse and extended wear on the filtration efficiency of N95 masks. Let’s break down the findings and practical advice for those relying on these essential respirators.

What is an N95 Filtering Facepiece Respirator?

An N95 respirator is a specialized mask designed to filter out at least 95% of airborne particles, such as dust, bacteria, and viruses. Unlike surgical masks, which protect against droplets, N95 respirators provide a tight seal around the face, making them ideal for environments with airborne contaminants.

Extended Use and Reuse: What Do They Mean?

• Extended Use: Wearing the same N95 mask for prolonged periods without removing it.
• Reuse: Wearing the same N95 mask across multiple sessions with breaks in between.

These practices, while not ideal, have become necessary in situations with limited mask supplies.

Filtration Efficiency: Why It Matters

Filtration efficiency refers to the mask’s ability to filter out harmful particles. When masks are reused or worn for extended periods, their efficiency can decline, making it essential to understand how to maintain protection levels.

Key Findings from the JAMA Network Study

The JAMA Network Open cohort study observed the filtration efficiency of N95 masks used under extended and reuse conditions. The study found:

• N95 masks maintained sufficient filtration efficiency for up to five reuses under controlled conditions.
• After five cycles, efficiency began to drop significantly, making further reuse less effective.
• Masks exposed to moisture or heavy contamination also showed reduced efficiency, emphasizing the need for cautious handling.

Practical Guidelines for Safe Reuse and Extended Use

1. Limit Reuse: If possible, reuse should be limited to a maximum of five times.
2. Storage Tips: Store the mask in a clean, breathable container (e.g., a paper bag) between uses to reduce contamination.
3. Handle with Care: Avoid touching the inner part of the mask. Inspect it before each use to ensure there’s no visible damage.
4. Consider Sanitization: While some methods like UV light and hydrogen peroxide vapor can sanitize masks, these processes are best conducted by professionals to avoid damaging the mask.

Comparing N95 Masks to Other Masks

While N95 respirators offer excellent filtration efficiency, they are not the only option. KN95 masks provide similar protection but follow different regulatory standards. Surgical masks are less protective against small airborne particles, focusing more on droplet transmission.

Conclusion

The JAMA Network Open study highlights that while reusing and extending the use of N95 respirators can be effective for a limited number of times, caution should be taken. For the best protection, single-use is still recommended where possible. In high-demand scenarios, following best practices for reuse can help maintain safety without compromising the mask’s efficiency.