A virucidal face mask based on the reverse‐flow reactor concept for thermal inactivation of SARS‐CoV‐2

Abstract

While facial coverings reduce the spread of SARS-CoV-2 by viral filtration, masks capable of viral inactivation by heating can provide a complementary method to limit transmission. Inspired by reverse-flow chemical reactors, we introduce a new virucidal face mask concept driven by the oscillatory flow of human breath. The governing heat and mass transport equations are solved to evaluate virus and CO 2 transport. Given limits imposed by the kinetics of SARS-CoV-2 thermal inactivation, human breath, safety, and comfort, heated masks may inactivate SARS-CoV-2 to medical-grade sterility. We detail one design, with a volume of 300 ml at 90 C that achieves a 3-log reduction in viral load with minimal impedance within the mask mesh, with partition coefficient around 2. This is the first quantitative analysis of virucidal thermal inactivation within a protective face mask, and addresses a pressing need for new approaches for personal protective equipment during a global pandemic.

Challenges and Controversies in COVID-19: Masking the General Population may Attenuate This Pandemic's Outbreak

“…It has been proposed that purposefully engineered materials with nanostructured surfaces can eliminate enveloped viruses such as SARS-CoV-2 i.a., on masks and be self-disinfectant ( 85 ). Other ways in which materials technology can improve masks is exemplified by a mask under development that lets some SARS-CoV-2 penetrate the mask, but heat-inactivates it ( 86 ). Guha et al suggest that electret materials (i.e., those with a permanent electric charge) may be advantageous for masks ( 87 ).…”

What do masks mask? A study on transdermal CO2 monitoring

“…On the other hand, a recent study showed that commercially available powered air purifying respirator that enhance breathability could prevent headache related to PPE [31] induced by hemodynamic alterations [32] . We are confident that our device will support the rapidly advancing research on filter materials [ 33 , 34 ] and designs [ 35 , 36 ] will lead to engineering of ergonomic masks that do not compromise on filter performance and breathability.…”

Materials in advanced design of personal protective equipment: a review

“…For similar aim, scientists from Massachusetts Institute of Technology (MIT) incorporated a copper mesh into the mask. By applying an electrical current through the mesh, large amounts of ohmic heat are generated, which greatly raise the local temperature and the microbes are killed [ 97 ] . Another approach to kill the aerosol pathogens adhered on the mask relies on the radical species produced by high electric field ( Fig.…”