Masks have become an important part of everyday life, protecting both the wearer and individuals nearby from the spread of infectious diseases, most notably severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the coronavirus that causes coronavirus disease 2019 (COVID-19). However, these masks are easily contaminated, whether through continued use or by the wearer touching the mask fabric with contaminated hands, therefore reducing the efficacy and exposing the user to these contagions. When the mask becomes contaminated, it can be discarded, which produces large amounts of waste that will end up in a landfill, or it can be washed, which is costly, wasteful, and time consuming. Our solution to this problem is a mask apparatus that can sanitize itself quickly on demand. The user wears the shell, which contains the fully retracted mask, on a string like they would a necklace. When the mask is required, it is easily pulled out of the shell and can be worn for as long as the user needs it. When it is safe to remove the mask, the user simply pushes a button and the mask retracts back into the shell, where it is then sanitized for the next use. The design of the apparatus features a retractable cloth mask that is sanitized using ultraviolet-C (UVC) radiation while confined safely within an outer shell, minimizing unwanted exposure to the wearer. UVC radiation at wavelength 222 nm has been shown to destroy the outer shell of coronaviruses similar to SARS-CoV-2, inactivating 99.9% of the virus when exposed at a dosage of 2 mJ/cm2. The 28 light-emitting diode (LED) lamps used in this prototype produce this specified wavelength UVC and are separated into 4 strips located in different locations within the shell. Glass rods were used within the shell to guide the mask fabric into a zig-zag shape when fully retracted to maximize exposure to the UVC. To further reduce waste, two lithium-ion rechargeable batteries were used as the power supply for the lamps. The efficacy of this design for inactivating the SARS-CoV-2 coronavirus on the mask was determined indirectly using nano membrane UV sensors placed on the mask fabric, showing that the specified wavelength of UVC radiation can be applied for the required time on all surfaces of the mask. This mask apparatus can directly benefit both front-line healthcare workers as well as individuals going about their daily lives by eliminating pathogens present on their masks, therefore reducing the spread of deadly infectious diseases.
Bachelor of Science (B.S.)
College of Medicine
Burnett School of Biomedical Sciences
Crawford, Matthew, "Developing A Self-Sanitizing Mask to Combat the Spread of Infectious Disease" (2021). Honors Undergraduate Theses. 959.