The COVID-19 pandemic has prompted innovation in face masks, including through a US BARDA mask innovation challenge. According to BARDA's target product profile, the main performance measures for its challenge are Thermal Burden & Moisture Retention, Breathability, Leakage Ratio, and Filter Efficiency. The challenge will result in two top winning designs and two runner-ups, with at least one of the four winning designs being commercially available and costing less than $1 per unit on or before December 31, 2024. This availability would be measured if the mask is sold on Amazon for at least six consecutive months at a price of less than $1 per unit (or up to $25 per unit for reusable masks lasting at least a month of daily usage). The resolution of this question will be determined by whether any of the winning designs meet these criteria.