Is the fit of N95 facial masks effected by disinfection? A study of heat and UV disinfection methods using the OSHA protocol fit test

Abstract

Abstract The current COVID-19 pandemic has highlighted global supply chain shortcomings in the US hospital delivery system, most notably personal protective equipment (PPE) and COVID-19 is found on these masks ∼7 days. Recent work from our group has shown two promising disinfection methods for N95 facial masks, dry heat (hot air (75 °C, 30 min) and UVGI which is UVGI 254 nm, 8W, 30 min. Using N95 five models of N95 masks from three different manufacturers we determined the following: 1) Hot air treated N95 masks applied over 5 cycles did not degrade the fit of masks (1.5% change in fit factor, p = .67), 2) UVGI treated N95 masks applied over 10 cycles were significantly degraded in fit and did not pass quantitative fit testing using OSHA testing protocols on a human model (−77.4% change in fit factor, p = .0002). NOTE We would like to share our results with the community as soon as possible. Be mindful that this report is a pilot study and a work in progress. We will have more results in the coming days and weeks. We recommend that hospital policy and procedures be respected and adhered to. Do not use anything in your home to disinfect contaminated equipment. Please do not heat your masks in a home oven!