MIT researchers say you’re no safer from Covid indoors at 6 feet or 60 feet(cnbc.com)
cnbc.com
MIT researchers say you’re no safer from Covid indoors at 6 feet or 60 feet
https://www.cnbc.com/2021/04/23/mit-researchers-say-youre-no-safer-from-covid-indoors-at-6-feet-or-60-feet-in-new-study.html
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Just read the article and came to say the same thing. The researchers' point was that the restrictions on indoor capacity are not helping, and should be done away with. You're no safer at 60 feet, because your safety depends a lot more on other variables besides distance. The headline could just as well have stated: "you're just as safe at 6 feet as you would be at 60 feet".
This is in line with what we've been seeing for the last 6 months.
Zeynep Tufekci clears this up;
Before this gets out of hand. "Distance doesn't matter" IS NOT what "it's airborne" or primarily aerosol-transmitted means or implies, and the headline is not reflecting correctly a modeling paper they are using says.
What's true is that in a "well-mixed" room (VERY IMPORTANT ASSUMPTION IN THE MODEL IN THAT PAPER BEING REPORTED ON), if you spend long enough time, distance isn't completely protective which IS NOT AT ALL THE same as "distance doesn't matter" or that 6 and 60 feet are the same.
Perhaps the most important misunderstanding has been assuming aerosols=long distance only. No, they do not teleport from a person to over two feet away a la "beam it over there, Scotty." Aerosols ALSO concentrate around the person and dilute with distance.
https://twitter.com/zeynep/status/1385707216280375298
Before this gets out of hand. "Distance doesn't matter" IS NOT what "it's airborne" or primarily aerosol-transmitted means or implies, and the headline is not reflecting correctly a modeling paper they are using says.
What's true is that in a "well-mixed" room (VERY IMPORTANT ASSUMPTION IN THE MODEL IN THAT PAPER BEING REPORTED ON), if you spend long enough time, distance isn't completely protective which IS NOT AT ALL THE same as "distance doesn't matter" or that 6 and 60 feet are the same.
Perhaps the most important misunderstanding has been assuming aerosols=long distance only. No, they do not teleport from a person to over two feet away a la "beam it over there, Scotty." Aerosols ALSO concentrate around the person and dilute with distance.
https://twitter.com/zeynep/status/1385707216280375298
Agreed. It's criticizing the 6 foot rule not the 60, headline should be this buried quote:
"Six-feet social distancing rules that inadvertently result in closed businesses and schools are “just not reasonable,” according to Bazant.'"
"Six-feet social distancing rules that inadvertently result in closed businesses and schools are “just not reasonable,” according to Bazant.'"
> "indoor airborne transmission associated with relatively small, micron-scale aerosol droplets plays a dominant role in the spread of COVID-19"
More reason to use an N95 mask (vs. dust filters/cloth).
More reason to use an N95 mask (vs. dust filters/cloth).
...assuming that everyone is wearing masks, the article eventually clarifies.
No, it says:
> even when wearing a mask
Which implies it holds with or without a mask.
> even when wearing a mask
Which implies it holds with or without a mask.
The first sentence of the article does imply that, as you say, but the writer got the implication wrong.
Later in the article they quote the researchers:
> “We argue there really isn’t much of a benefit to the 6-foot rule, especially when people are wearing masks” since everyone in the room is breathing the same air, Bazant said in an interview. “It really has almost no physical basis because the air a person is breathing while wearing a mask tends to rise and comes down elsewhere in the room so you’re more exposed to the average background than you are to a person at a distance.”
> Without masks, however, Bazant said 6 feet would provide some additional protection against Covid-19 versus 3 feet. That’s particularly true if a person is breathing directly in your direction, creating what scientists call a “respiratory plume,” like a puff of smoke from a smoker. Their research was based on models that assume the air in the room is “well mixed” and that “the pathogen is distributed uniformly throughout,” they said in a follow-up statement to CNBC on Monday.
Later in the article they quote the researchers:
> “We argue there really isn’t much of a benefit to the 6-foot rule, especially when people are wearing masks” since everyone in the room is breathing the same air, Bazant said in an interview. “It really has almost no physical basis because the air a person is breathing while wearing a mask tends to rise and comes down elsewhere in the room so you’re more exposed to the average background than you are to a person at a distance.”
> Without masks, however, Bazant said 6 feet would provide some additional protection against Covid-19 versus 3 feet. That’s particularly true if a person is breathing directly in your direction, creating what scientists call a “respiratory plume,” like a puff of smoke from a smoker. Their research was based on models that assume the air in the room is “well mixed” and that “the pathogen is distributed uniformly throughout,” they said in a follow-up statement to CNBC on Monday.
> As for social distancing outdoors, Bazant says it makes almost no sense and that doing so with masks on is “kind of crazy.”
> “If you look at the air flow outside, the infected air would be swept away and very unlikely to cause transmission. There are very few recorded instances of outdoor transmission.” he said. “Crowded spaces outdoor could be an issue, but if people are keeping a reasonable distance of like 3 feet outside, I feel pretty comfortable with that even without masks frankly.”
^ The important thing that no one seems to be mentioning in the comments here. I'm surrounded with "informed" hyper-concerned liberals in a city and the amount of people wearing masks outdoors quite far away from anyone is making me question their sanity.
> “If you look at the air flow outside, the infected air would be swept away and very unlikely to cause transmission. There are very few recorded instances of outdoor transmission.” he said. “Crowded spaces outdoor could be an issue, but if people are keeping a reasonable distance of like 3 feet outside, I feel pretty comfortable with that even without masks frankly.”
^ The important thing that no one seems to be mentioning in the comments here. I'm surrounded with "informed" hyper-concerned liberals in a city and the amount of people wearing masks outdoors quite far away from anyone is making me question their sanity.
Is it just me or does the conclusion not follow from the data? They say that the 6 foot rule "has no physical basis" because 60 feet is just as dangerous/safe - but surely that's irrelevant? What about 3 feet? 1 foot? If 6 feet is safer than that, then the rule is just fine - optimal, even, if the danger plateaus!
tl;dr Headline could just as easily read "6 foot rule highly effective - just as safe as 60 feet!"
tl;dr Headline could just as easily read "6 foot rule highly effective - just as safe as 60 feet!"
"The 6ft rule" is probably a decent proxy for "stay out of each other's personal space".
I think people miss that public policy is 1 part science and 1 part "making rules that might actually help given that people are idiots". Rules that are too complicated, subtle or onerous just won't get followed. We have enough trouble getting people to do the 6ft thing.
I think people miss that public policy is 1 part science and 1 part "making rules that might actually help given that people are idiots". Rules that are too complicated, subtle or onerous just won't get followed. We have enough trouble getting people to do the 6ft thing.
its more like statistical reality.
if you arbitrarily take 2 random people, 6 feet is a reasonable, risk free place.
but indoors with little ventilation, and circulating people, its garunteed the whole place will have covid if a single person walked around coughing.
its realistically about how effectively fresh air replaces any given persons emissions.
if you arbitrarily take 2 random people, 6 feet is a reasonable, risk free place.
but indoors with little ventilation, and circulating people, its garunteed the whole place will have covid if a single person walked around coughing.
its realistically about how effectively fresh air replaces any given persons emissions.
If you're inside a place with a breeze, it's literally impossible to contract it if you're upwind. It's even difficult to contract it downwind if the flow rate is high enough.
* https://www.cnn.com/2020/11/19/us/gym-ventilation-covid-trnd...
* https://www.sfgate.com/science/article/China-study-suggests-...