How to Sanitize N95 Masks for Reuse: NIH Study
Exposing contaminated N95 respirators to vaporized hydrogen peroxide (VHP) or ultraviolet (UV) light appears to eliminate the SARS-CoV-2 virus from the material and preserve the integrity of the masks' fit for up to three uses, a National Institutes of Health (NIH) study shows. Dry heat (70° C) was also found to eliminate the virus on masks but was effective for two uses instead of three.

• Researchers compared four methods for decontaminating the masks, which are designed for one-time use: UV radiation (260 – 285 nm); 70° C dry heat; 70% ethanol spray; and VHP.

• All four methods eliminated detectable SARS-CoV-2 virus from the fabric test samples, though the time needed for decontamination varied. VHP was the quickest, requiring 10 minutes. Dry heat and UV light each required approximately 60 minutes. Ethanol required an intermediate amount of time.

• The researchers found that masks that had been decontaminated with ethanol spray did not function effectively after decontamination, and they did not recommend the use of that method.

• By contrast, masks decontaminated with UV and VHP could be used up to three times and function properly. Masks decontaminated with dry heat could be used two times before function declined.

• A shortcoming of the study is that it tested the masks for only 2 hours, whereas in clinical practice, they are being worn for much longer periods.

After the study is peer-reviewed, the Centers for Disease Control and Prevention (CDC) may update its recommendations, she said.

Dr. N●●●a s●●●i and 1 others like this5 shares