1/10 - "To make indoor communal spaces safer, they need to be 'well-ventilated.' But what does that mean? We need to think about controlling the source of the virus indoors, about mixing more outdoor air with indoor air, and about air filtration and cleaning devices."

2/10 - "Ventilation concerns are not limited to restaurants and schools. Recently, a report from the University of California San Francisco noted 'exceedingly poor ventilation' at the San Quentin State Prison (USA), which saw a huge outbreak of more than 2,200 cases."

3/10 - "We can’t ventilate and air purify our way out of the need to wear masks, reduce occupancy in indoor spaces (or avoid many of them all together),and phys dist. The most important way to make indoor spaces safer is to decrease community #Covid19 spread as much as possible."

4/10 - " #SARSCoV2 gets into the air via human breath. So we should start by reducing the number of humans in a space, masking those who have to enter, and limiting activities like singing or shouting that can propel even more virus-laden particles into the air."

5/10 - Ventilation: "the air in your home probably changes over once every hour or two hours. We’re aiming for an air exchange rate of, like, six per hour. That recommendation comes from studies of tuberculosis transmission."

6/10 - "There’s no perfectly ‘safe’ level of ventilation because we don’t actually know what ‘safe’ is, since we don’t know how much exposure leads to transmission of #SARSCoV2.”

7/10 - Air filters can work too — if used properly: "The goal in ventilation is to replace potentially virus-laden air indoors with virus-free air. One way to do this is to bring more outdoor air inside. The other way is to filter the indoor air itself."

8/10 - "It starts with getting a good air filter. Often in buildings, a filter will be improperly sealed so that some unfiltered air sneaks past it and recirculates in the building; this downgrades its filtering ability."

9/10 - "There’s yet another option for removing virus from the air: killing it with ultraviolet lamps. However it is not recommended for the average consumer.
While they can be effective, there is not enough testing/certification for these devices.”

10/10 - "Even if you can’t reach the target — six air changes per hour — if you can improve, that will still be helpful. Do what you can, because that will reduce the risk of transmission. Don’t give up. There are no risk-free situations in a pandemic.” https://www.vox.com/science-and-health/2020/8/19/21364031/coronavirus-air-purifiers-filter-hepa-merv-ventilation