According to the United States National Institutes of Health (NIH), research has confirmed different effective methods can be used to decontaminate the N95 masks so that they can be used more than once.
The research titled “Assessment of N95 respirator decontamination and re-use for SARS-COV-2” was carried out at Rocky Mountain Laboratories of the National Institute of Allergy and Infectious Diseases.
During the research, experts used live SARS-COV-2, the Coronavirus which causes COVID-19, to test the material of N95 masks. They studied which decontamination methods are effective against the Coronavirus and how they affected the integrity of N95 masks.
The experts used four methods to kill the Coronavirus; dry heat, UV light, ethyl alcohol, and vaporized hydrogen peroxide (VHP).
Except for ethyl alcohol, the experts have recommended all methods to be effective in wiping out the Coronavirus. It is because ethyl alcohol degrades the material of the N95 mask.
The order of prevalence for decontamination methods is given below:
- UV Light
- Vaporized hydrogen peroxide (VHP)
- Dry Heat (Oven)
N95 masks remain fit for use after at least three rounds of decontamination with VHP and UV light. The fourth round of decontamination deteriorates the quality of masks. N95 masks become unfit for use after two rounds of decontamination with dry heat.
Dr. Vincent Munster, one of the authors of the research, said:
VHP and UV light are the best methods to be used in a healthcare setting. But, in nursing homes, for instance, where there are no such facilities, the dry heat can be used. All you need is an oven.
It is important to point out that the research is yet to be peer-reviewed. However, NIH decided to publish the research because it only validated and extended existing work instead of recommending untried methods. NIH is hopeful that the research could be helpful for medical professionals during the pandemic.