I'm sharing my ObservableHQ notebook that gives COVID aerosol risk estimates for schools, work, shopping, and other activities. You can adjust sliders to get counterfactuals/what-ifs for improving ventilation, decreasing time, etc. good risk estimator is very helpful when navigating competing ideas. Some people favor ventilation. Some people better masks. Some, spacing and distancing.It's based on the decades old Wells-Riley aerosol disease model. A google sheets risk calculator with a ton of documentation was built by Prof Jose Jimenez of Univ Colorado-Boulder. ( a complex google sheets workbook).It can help you think about doing A or B.I didn't make any of the modeling equations. I just "reskinned" the google sheet as a menu based system with sliders and radio boxes. But it's more approachable than the google sheet.Hope this is useful.