Construction and validation of UV-C decontamination cabinets for filtering facepiece respirators
The COVID-19 pandemic has tested our ability to adapt to a widespread, global crisis. While hardly any part of society has avoided the effects of COVID, a prime example of this is ongoing medical supply shortages, which hampered the ability of front-line workers to care for COVID and non-COVID patients alike. Shortages of N95 filtering facepiece respirators—effective devices for protecting healthcare workers from infection—occurred early in the pandemic, when demand for these devices began to outpace their production. Medical facilities were thus required to ration N95 respirators, and in some cases, re-use them. However, while re-using respirators can be an important strategy to prevent critical shortages, the decontamination process must be effective, safe, and can’t compromise the performance of the respirator. In a recent paper published in Applied Optics, a team comprised of engineers, scientists, and medical students from Harvard Medical School, University of Toledo, UCSF and Stanford, provide evidence-based design principles for three ultraviolet-light-based decontamination strategies that are appropriate for high- as well as low- and middle-income countries (LMICs). Irradiation of light in the UV-C portion of the spectrum has been used previously to deactivate a variety of different bacterial and viral pathogens, including C. Difficile, MRSA, and other airborne coronaviruses. However, the effectiveness of this strategy depends on the light dose reaching the items being decontaminated. The authors demonstrate design principles to achieve effective UV-C decontamination, with an emphasis on design viability for LMICs. They also provide optical models and testing procedures that will allow the implementation of these designs. Effective methods of N95 respirator decontamination protect front-line workers, allowing them to continue battling the pandemic and saving lives.