Authors: Xavier Pereira, MD, David Pechman, MD
Advanced Sterilization Products (ASP) STERRAD sterilizers (STERRAD 100S Cycle, STERRAD NX Standard Cycle, and STERRAD 100NX Express Cycle) received emergency approval for decontamination of N95 respirators on April 11, 2020.
The world is currently facing an unprecedented public health crisis caused by the coronavirus disease (COVID-19). The respiratory disease, caused by the novel coronavirus SARS-CoV-2, can be transmitted by respiratory and airborne droplets1. This has led to a severe shortage of disposable N95 respirators, which are routinely used to reduce exposure to airborne particles by filtering out 95% of particles in the air2. Disposable N95 respirators are not approved for routine decontamination and reuse as a standard of care, however, due to the current crisis, the Food and Drug Administration (FDA) has emergently approved ASP’s STERRAD sterilization systems for the use in decontaminating supplies of N95 respirators with exposure to the SARS-CoV-2 virus3.
The approved STERRAD decontamination systems use vaporous hydrogen peroxide (VHP) to decontaminate elements within a chamber. At the beginning of the cycle, aqueous hydrogen peroxide solution is injected into a vaporizer and vacuum pump assembly that concentrates and vaporizes the solution at low temperatures and sub-atmospheric pressures. The vaporized hydrogen peroxide is then allowed to permeate throughout the chamber to ensure contact with surfaces in need of sterilization. Electrical energy is then used to transform the vapor into gas plasma and allowed to vent, which brings the chamber back to atmospheric pressures. The cycle is repeated once more to complete a full decontamination cycle.
This Emergency Use Authorization clearance was approved based on the totality of scientific evidence available to the FDA since there is no available data on the use of VHP to decontaminate N95 respirators of SARS-CoV-2.
The novel use of this already FDA-Approved device was approved under the FDA Emergency Use Authorization.
Decontamination is indicated for compatible N95 respirators for single-user reuse during the COVID-19 pandemic4. This device is also already cleared for sterilization of certain metal and non-metal medical devices.
The use of STERRAD decontamination is contraindicated for N95 respirators containing cellulose-based materials, heavily soiled respirators, and respirators that have been decontaminated on more than two occasions.
- van Doremalen N, Bushmaker T, Morris DH, et al. Aerosol and Surface Stability of SARS-CoV-2 as Compared with SARS-CoV-1. N Engl J Med. 2020;382(16):1564-1567. doi:10.1056/NEJMc2004973
- Nogee D, Tomassoni A. Concise Communication: Covid-19 and the N95 Respirator Shortage: Closing the Gap. Infect Control Hosp Epidemiol. April 2020:1-4. doi:10.1017/ice.2020.124
- Hinton, DM. ASP STERRAD COVID-19. https://www.fda.gov/media/136884/download. Accessed April 16, 2020.
- FDA Authorized N95 Respirators. https://www.fda.gov/media/137021/download. Accessed April 15, 2020.