Scientists at Hamilton's Rocky Mountain Laboratories have made an initial determination that, with the proper procedure, N95 respirators can be re-used up to three times. The face masks are designed for single-use by healthcare providers to reduce exposure to airborne infections such as COVID-19. The National Insititutes of Health study found that if treated with vaporized hydrogen peroxide (VHP), the respirators can be totally cleaned and re-used. In the laboratory tests, conducted by an RML team headed by Dr. Vincent Munster, four different types of decontamination were used - 70-degree dry heat, ultraviolet light, 70 percent ethanol spray and vaporized hydrogen peroxide. The vaporized hydrogen peroxide was most effective.

Dr. Marshall Bloom cautioned that this was a laboratory test in a highly controlled setting, and that the Food and Drug Administration is looking at two companies that could properly decontaminate the respirators. Do-it-yourself VHP is not recommended and can be extremely dangerous. VHP can cause damage to the lungs, eyes and skin. The study to validate decontamination methods for re-use of the N95 respirators was presented in a preprint article this week. The findings are not yet peer-reviewed but were released due to the COVID-19 threat and the national shortage of personal protective equipment. Rocky Mountain Laboratories in Hamilton are part of the National Institute of Allergy and Infectious Diseases of the National Institutes of Health.