Since the beginning of America's battle with the novel coronavirus, N95s, the close-fitting respirators worn instead of face masks to protect frontline workers from infectious aerosols and respiratory droplets, have been in short supply.The respirators, most manufactured by 3M and Honeywell, are used globally and act as the crux of personal protective equipment (PPE) for hospital staff.Traditionally they are donned and discarded after a single patient examination, but shortages and supply chain issues during the pandemic have resulted in countless stories of doctors and nurses reusing a single respirator per shift.