As we seek to return to normalcy without a vaccine, COVID-19 confronts us with a troubling reality. We spend 90% of our time indoors in the U.S. and Europe, and scientific evidence indicates we are nearly 20 times more likely to be infected by the virus indoors than outdoors. COVID-19 has impacted many indoor settings such as schools, offices, churches, restaurants and bars, with prisons, meatpacking plants, and long-term care facilities being most affected due to high occupancy, poor ventilation and vulnerable populations.

Increasingly, scientists believe airborne transmission is a major route for the spread of COVID-19. Viral respiratory droplets released from coughing, sneezing, talking, and breathing can aerosolize into smaller particles, stay suspended in the air for hours, and travel significantly farther than six feet. A key scientific debate has been whether the virus is infectious in aerosols.