For every extra body you take out of a room, you are lowering the risk that somebody infected is in there to start off with. Then assuming that someone in that environment is infected, there is a gradient of respiratory droplets from that person that radiates out. So, certainly, having people spread out more in enclosed environments is an important way to reduce infection, but it’s not the solution to controlling all infections. Having a restaurant at half capacity that is still enclosed and has no or very little air exchange is going to be just as risky, but to fewer people.
Memo to Self:
Add the concept of dose-time to your Covid-19 risk reduction strategy.
Add a link to the Medscape interview with Erin Bromage.