Researchers found no changes in respiratory integrity or filtration efficiency among several N95 respirators after 25 decontamination cycles, according to a new study. The results appear in the American Journal of Infection Control.
All the N95 respirators met the primary endpoints of function and effectiveness, passing 25 user seal checks and eight quantitative and four qualitative fit tests, in addition to maintaining filtration efficiencies of 95% or above throughout the study.
In keeping with guidance from the Centers for Disease Control and Prevention and the Occupational Safety and Health Administration, staff at Beth Israel Deaconess Medical Center (BIDMC) re-used N95 respirators to ease supply constraints, employing vaporized hydrogen peroxide (VHP)—a common, effective environmental disinfection agent—as a decontamination method.
In the new study looking at the approach evaluated between June and August of 2020, physician-scientists at BIDMC reported that a common type of N95 respirator reprocessed with VHP maintained its function and effectiveness through 25 cycles of re-use.
“It is important that we now find ways to scale and translate this disinfection capability to smaller hospitals and resource-limited healthcare settings that could benefit just as much – perhaps more – from this type of personal protective equipment reprocessing in future disaster scenarios,” says lead author Christina F. Yen, MD, who was a fellow in medicine at BIDMC during the research and is now at the University of Texas, Southwestern.
Yen and colleagues conducted a series of qualitative and quantitative tests to evaluate both the function and effectiveness of seven N95 respirators that were used by three male and four female volunteers from June to August of 2020. These tests comprised a user seal check (performed by subjects donning and doffing the respirators), qualitative and quantitative respirator fit testing, and filtration efficiency testing, which assesses the ability of the respirator to filter out particles.
“In order for reprocessing to be a realistic option for healthcare facilities, certain steps need to be taken,” says senior author Preeti Mehrotra, MD, MPH, senior medical director of Infection Control at BIDMC. “Reprocessing can be made possible by creating relationships among infection prevention, occupational health, environmental services, and other relevant departments within hospitals to facilitate implementation of appropriate technologies and advocating for the inclusion of personal protective equipment reprocessing in epidemic and pandemic planning.”
Co-authors included Robert Seeley, MS, CSP, Patrick Gordon, DNP, RN, CIC, Sharon B. Wright, MD, MPH, Dana Pepe, MD, MPH of BIDMC; and Lalitha Parameswaran, PhD of Massachusetts Institute of Technology, Lincoln Laboratory.