Decontamination and Reuse of N95 Respirators with Hydrogen Peroxide Vapor to Address Worldwide Personal Protective Equipment Shortages During the SARS-CoV-2 (COVID-19) Pandemic

Abstract

The SARS-CoV-2 (COVID-19) pandemic has placed a tremendous amount of strain on resources in the health care setting. One of the most pressing issues is the rapid depletion of personal protective equipment (PPE) used in the care of patients. This is a significant concern for health care workers' health and safety. Many entities have depleted or soon will exhaust their stockpile of PPE despite adopting PPE-sparing practices as the number of COVID-19 cases in the United States increases at an almost exponential rate and manufacturers struggle to keep up with the worldwide demand. This potential shortage is particularly concerning for commonly used N95 respirators and powered-air purifying respirators (PAPRs). Recently, the US Occupational Safety and Health Administration (OSHA) 1 even temporarily suspended the requirement to perform annual fit testing of respirators to allow entities to conserve respirators and preserve them for patient care. These measures are unprecedented and highlight the urgent need for entities to develop solutions to proactively address what could be potentially a grave occupational health issue.At Duke University and Health System, we have evaluated and will begin using hydrogen peroxide vapor to decontaminate and reuse N95 respirators. In this communication, we briefly discuss the decontamination validation process and post-decontamination performance validation conducted at Duke. This validation, which is supported by previous laboratory testing, funded by the US Food and Drug Administration (FDA), demonstrated that N95 respirators still met performance requirements even after decontamination with hydrogen peroxide vapor in the laboratory setting for over 50 times. 2 While previous studies have shown the applicability of the hydrogen peroxide vapor process, we have also confirmed that the respirator still functions as designed, using our standardized human N95 fit testing methodology. We will now use this internally validated and Duke Institutional Biosafety Review Committee (IBRC)-approved laboratory decontamination process in the clinical setting to dramatically extend the life of our N95 respirators. We hope that sharing our processes through this brief communication can help other entities with access to hydrogen peroxide vapor to evaluate the potential applicability of this technology at their facility or partner with those who may already have this capability, including other private-sector life science organizations. Process/MethodWe, like others, have implemented many Centers for Disease Control and Prevention (CDC)-approved N95 reuse practices, including employees reusing their own N95s for the duration of their shifts. However, this alone may not be adequate to meet our anticipated need with various centers reporting multiplefold higher use of PPE as their caseload increases. In the interest of our workforce safety, the goal was thus to extend the life of our existing supply.

Reuse of N95 Masks

“…A second alternative is fumigation. Duke University Hospitals (Durham, North Carolina) are now using-and testing-systems manufactured by Bioquell, Inc. (Horsham, Pennsylvania), which exposes the masks to vaporized hydrogen peroxide [1]. Depending on the machine used, the amount of hydrogen peroxide gradually builds up to 300-750 ppm (1 ppm = 1 ×10 −6 ) and is held there for 20 min.…”

“…Using the Bioquell Z-2 hydrogen peroxide vapor generator ( Fig. 4), the Duke staff can disinfect 1250 masks per cycle, and 2500 per 12 h shift [1].…”

“…Hospitals staff can disinfect, for reuse, 1250 masks per cycle, and 2500 per 12 h shift [1]. A larger version of the set up manufactured and operated by Battelle (Columbus, Ohio) can process 80 000 used masks per day, enough to supply multiple hospitals and even hospital systems [10].…”

“…Now, to meet the critical and quickly intensifying need, Chinese and American engineers are devising new procedures for decontaminating and reusing masks that hospitals already have on hand ( Fig. 1) [1]. Although some of these procedures require specialized equipment, others are simple enough to use at home ( Fig.…”

“…N95 masks, like the "CLEAN" ones shown here, are being reused at Duke University Hospitals (Durham, North Carolina) after decontamination using a Bioquell (Horsham, Pennsylvania) Z-2 device (see Fig. 2) that uses hydrogen peroxide vapor for sterilization [1]. Credit: Duke University, with permission.…”