By all the epidemiology information I've read with social distancing plus extra ventilation when inside.
Air filtration devices like ionizers are also useless to detrimental as the particles get trapped inside them and they do little to maximize air flow.
The one factor that seems to get the least attention (in the real world) is the ventilation issue and just setting up a small device in a room is not the best remedy, airflow is.
Opening doors, windows and running fans while having adequate intake of the air to keep basically flushing fresh air through an area is best. A closed air system with out industrial style filtration, like in a hotel or a home, just recirculates the "bad" air.
One study of a hotel showed how one infected maid contaminated an entire floor of a hotel because of the closed air system. This lead to the infection of several of the guests in rooms on the floor she was responsible for.
I also read where a teacher, who had been in meetings prior to classes starting, was expressing frustration because they were told to keep windows and doors open for ventilation because of Covid and then told to keep doors closed because that's an "active shooter" deterrent. It's a tricky enough situation with Covid alone. I can't imagine how scary a situation it must be for teachers, parents, staff and students but that's a whole different discussion.
So double mask with a surgical mask, N95 (or equal type and not just a single layer cloth mask but a three ply) and wear a face shield while indoors. Maximum air filtration and flow are very important determinants of safety while indoors but not being mentioned enough. They are an integral part of the remediation recommendations most mentioned in epidemiology studies on Covid.
So it's
1) double mask
2) face shield
3) social distance and
4) fresh air flow
❤
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