COVID-19 Global Pandemic Planning: Decontamination and Reuse Processes for N95 Respirators

Douglas Jay Perkins; Steven Villescas; Terry H Wu; Timothy B Muller; Steven Bradfute; Ivy Foo-Hurwitz; Qiuying Cheng; Hannah Wilcox; Myissa Weiss; Chris Bartlett; Jens Langsjoen; Phil Seidenberg

Based on the available information at the time, we prioritized HPV decontamination as our first choice, and UVGI as a viable second option. However, since we did not have any pre-existing configurations that contained large chambers with external sources of HPV, we started testing in HPV generators in different environments. Learning through trial and error, in an iterative process and with open minds, was critical to our eventual success. Initially, we tested the process in a standard room (22' x 8' with 8' ceilings; 131 m 3 ) and were meet with challenges. For example, the room did not have adequate airflow to cool the environment to an optimal temperature between the HPV processing runs. This resulted in the Bioquell instrument shutting down during the gassing phase due to overheating, thereby, reducing the desired levels of H2O2 (ppm). It became apparent that waiting for a protracted period to allow the room to reach the desired temperature for a subsequent run would not achieve desired efficiently. As such, we eliminated this environment as a viable option and set up the HPV decontamination process in one of four unused operating rooms. Based on their intended use, such environments are constructed with optimized climate control, outside air exchanges, and finishes that are monolithic, scrubbable, and free of crevices and fissures. Sterilization of operating rooms with portable HPV generators, such as the instrument we employed, is an industry standard for no-touch disinfection of the environment to prevent transmission of pathogens. During the HVP exposure application we further isolated the operating room by sealing off the heating, ventilation and air conditioning (HVAC) supply / exhaust ducts and door with polyethylene sheeting and tape. Upon setting up the HPV process in the operating room, we achieved immediate . CC-BY-NC-ND 4.0 International license It is made available under a author/funder, who has granted medRxiv a license to display the preprint in perpetuity.