The SARS-CoV-2 virus has put a strain on the supply and distribution of N95 masks, with some hospitals needing to reuse masks. Currently, vaporized hydrogen peroxide mask disinfection systems being deployed at multiple locations throughout the United States. The systems are being deployed in shipping containers and in small rooms. Such rooms will be of a different size, have different materials and have varying air change rates, and all these parameters will impact the effective VHP disinfection dose that the masks receive. Failure to account for these losses may inhibit effective N95 mask disinfection when applied in such locations. This paper describes a spreadsheet model that allows a user to estimate the VHP concentration in air of a room being used to disinfect masks and accounts for room size, vaporized hydrogen peroxide deposition to surfaces and air change rate using a mass balance approach. It can also be used to estimate the mass of disinfectant that is deposited on masks.
Technical Note (NIST TN) - 2091