Erecting Barriers to Coronavirus: 'You wouldn't board an airplane that didn't have regular maintenance, but many buildings don't get an annual checkup.'.

• Author: Walsh, Colleen

JOE ALLEN, assistant professor of exposure assessment science at the Harvard School of Public Health and director of its Healthy Buildings Program, suspects that broader airborne transmission of the coronavirus is likely, and thinks certain precautions indoors and out can help reduce its spread.

Allen spoke with the Harvard Gazette about ways to stay safe during the pandemic. The interview was edited for clarity and length.

Gazette: The Centers for Disease Control and Prevention has recommended individuals wear cloth face coverings in public settings where social distancing is difficult. What do you think?

Allen: Everyone should be wearing masks--the point is that it's a really important and powerful social cue. It's a reminder to all of us that this risk is everywhere, and we all need to do our part--it actually should be considered a badge of honor. If I'm wearing a mask out in public, it's telling you that I'm concerned about your health. I'm worried 1 might be infectious, asymptomatic or symptomatic, and I'm taking this seriously so I don't infect others. A mask also serves as a reminder not to touch your nose, face, or mouth, which are points of transfer for the virus.

Gazette: Are there certain materials that are better than others that people can use to make their own masks?

Allen: I recommended using something that most people would have in their home right now: a 100% cotton t-shirt. The science says that can be fairly effective for capturing large droplets if I cough or sneeze, but also it can filter some of the smaller virus particles--not as good as a commercial mask, but good enough and certainly better than nothing.

Gazette: You are a specialist on healthy buildings. How do you see life in offices changing when people eventually make the transition back to working on site?

Allen: Companies are going to come back to a different world, where their workers have a heightened awareness about the risk of infectious disease transmission and how the building influences that. So, people's expectations are going to be very different. They're going to be paying attention to things like the density of the space and the air quality in the space.

I guarantee when everyone returns back to work that first day, we're all going to look around and notice if we do or don't have hand sanitizer. We're going to notice if there are too many people in a crowded conference room--that's just the reality we face. The positive side here is that we can...