Numerical model showing the flow of air and concentration of aerosols inside a campus bus. Credit: Zhihang Zhang, Jesse Capecelatro, Kevin Maki, Jim Smith and Jason Bundoff.
Short trips. Masks for everyone. Far fewer passengers than before.
Those are my top recommendations for how America’s school buses should take kids to and from school during the pandemic.
I am a professor of mechanical and aerospace engineering who studies the flow physics of particles and droplets. Since March, I have worked with my University of Michigan colleagues to measure COVID-19 risks on the buses college students use to get around our campus.
Based on our guidance, those buses now follow routes that take 15 minutes at most to complete, down from as long as 45 minutes before the pandemic. All passengers must wear masks, and the maximum occupancy is half of what it used to be. My recommendations for K-12 buses are similar.