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I don't know (and I'm not defending this validation, as I take issue with a number of premises) but my understanding of the justification is that restaurants can relatively easily space out/put dividers up between their tables (such that risk of transmission between parties at different tables is lower), but that no such accommodation can be made easily for the aisles, bathrooms, bar, and other intermediate spaces. Thus the rule, which around here is "wear a mask if you aren't seated at your table".

Given how restaurants around here are still packing people in, though, one has to assume that the initial table-spacing premise is compromised, undermining the whole endeavor.

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> my understanding of the justification is that restaurants can relatively easily space out/put dividers up between their tables (such that risk of transmission between parties at different tables is lower)

Because air doesn't move? It doesn't mix? On the contrary, the virus persists in the air for longer than an entire room air turnover.

Since Feb 2020, the studies show HVAC's air patterns in restaurants do infect other tables, quickly even. Roughly, air handling collects contaminated air and spews it on some tables in concentrated form (those tables experience all the air fast, not just subset of diffuse air more slowly; then in time all the air is mixed). Similar findings in 2021 for classrooms where student desks at risk are heat mappable based on HVAC configurations.

Grandparent post is right. You see other polls saying e.g. 60% of people being extra careful now with Omicron, at the same time, nearly 60% still going out to eat. So either people are stupid, or just don't understand because nobody's informing them. I'd suggest your post falls in the under-informed category: dividers are for how droplets work, but not for how air works.

Ridiculous we still don't deal with the air situation, but (a) way too much narrative was set back in the "it's not airborne" days for the media or masses to be interested in grappling, and (b) no landlord wants* to fix the air handling which was all sized for energy cost reduction not health.

* On HVAC upgrades, it's initially interesting that HVAC firms aren't upselling HEPA filtration etc. -- why isn't capitalism solving this problem? Surely they're lobbying for the new business! But then one remembers that 'venue shopping' or 'advice shopping' is a thing. Any HVAC firm under contract to workplace building owners is putting the relationship at risk if they tell the landlord or occupants on the record to spend a bunch of extra money. On the contrary, their incentive to keep the building contract is aligned with the landlord's incentive to not hear about having to spend 10x the original cost of the system on upgrading it.

Only an anecdote, but I recently visited a restaurant that prominently advertised they had installed a high end air filtration system, and it did smell kind of “filtered” inside (don’t know how to describe the smell but hopefully you know what I mean).

Perhaps the market will eventually move this way, and it just takes time? Certainly it is expensive so I don’t think the market will move this way unless consumers demonstrate they care and preferentially visit places with fancy HVAC.

It could be Ozone. Possibly harmful for human depending on concentration but sometimes used for human.

EPA says that just HEPA filter is enough to catch covid, so it seems that there are less chance to upsell filter only. Selling more appliances would be good. https://www.epa.gov/coronavirus/air-cleaners-hvac-filters-an...

The dividers are pretty silly if the virus is as airborne as is now believed.

They are. But limiting the number of people you’ve been potentially exposed to to just the people directly next to you is obviously safer than being exposed to every person between your table and the bathroom/exit.

If it's airborne, you're exposed to all of the people in the facility, and all of the people in it within the last few hours. The dividers likely make minimal if any difference.

sigh I didn’t say that the dividers help. I in fact explicitly agreed with you that they’re useless.

That being said, the virus isn’t magically going to fill the entire space equally from one infected person. There is a distance factor involved, and the closer you are unmasked the higher your risk. So only unmasking at your table cuts your risk pool down to the tables immediately proximate to you, rather than everyone you walked by, and anyone you shared the bathroom with. It’s not as safe as staying home, but it’s better than being unmasked the entire time.

Oh, and the risk isn’t going to hang around hours after the fact, unless if you’re in a completely unventilated space. Commercial restaurants change their air over a recommended 8 times an hour.

1. Air turnover is not the same as changeover. Turnover is only relevant if viral filtration is in place, which it generally isn't. Changeover is outside air, and for energy conservation, very little outside air is generally mixed in. (Some spaces do either or both of these. Airplanes provide an example of better filtration than usual, cruise ships are an example of more outside air than most buildings, and you can draw your own conclusions between those examples.)

2. Research shows takes less time to diffuse than you'd think, and lingers longer than you think. Since spring 2020 research has shown to wait till tomorrow if someone infected was in the space today.

3. Your own mask mitigates this, as does the amount of time you're breathing the infected space, as does the amount of human turnover (how many rolls of the dice of the space hosting an infected breather, and how long are they exhaling in the space).

> 2. Research shows takes less time to diffuse than you'd think, and lingers longer than you think. Since spring 2020 research has shown to wait till tomorrow if someone infected was in the space today.

Do you have a citation for this? I would be interested in reading this study.

1. The recommendation is 6-8 changes of outdoor air per hour. See ASHRAE 62.1. For comparison personal homes are recommended to change over their air 0.35 times per hour.

2. I would like to see that cross referenced against ventilation capacity. Again, restaurants are supposed to be changing their air over with outside air a lot, the idea that a properly ventilated space would have represent an infection risk days later is in the “doubt” category for me. Basically, please provide a source.

Heck, last time I was in Vegas I could barely smell people smoking a few feet away from me, the ventilation was that good. If cigarette smoke is the metaphor we’re going with for viral particles and dividers, that strongly implies that better ventilation yields a lower infection risk.

3. Exactly. This is an argument for masking when you’re not eating. It’s not 0 risk, but it’s lower. How much lower is debatable, and obviously depends on more circumstances than just masking policy alone.

Personally I’d rather just get takeout when local case loads are high, like right now.

The dividers, insofar as they impede overall airflow, might make things worse. Would like to know whether there's a study on that.

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