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A little sneeze goes a long way, and that's not good, an MIT scientist says

Lydia Bourouiba, an MIT professor and director of the Fluid Dynamics of Disease Transmission Laboratory, writes that our current six-foot safety zone is based on decades-old work in a laboratory and that might be putting health-care providers at risk.

In "Turbulent Gas Clouds and Respiratory Pathogen Emissions," Bourouiba shows rather graphically, via a couple of videos, how a sneeze can propel nasal droplets as far as 27 feet. Also:

Recent work has demonstrated that exhalations, sneezes, and coughs not only consist of mucosalivary droplets following short-range semiballistic emission trajectories but, importantly, are primarily made of a multiphase turbulent gas (a puff) cloud that entrains ambient air and traps and carries within it clusters of droplets with a continuum of droplet sizes. ... The locally moist and warm atmosphere within the turbulent gas cloud allows the contained droplets to evade evaporation for much longer than occurs with isolated droplets. Under these conditions, the lifetime of a droplet could be considerably extended by a factor of up to 1000, from a fraction of a second to minutes.

She notes that the current dichotomy between "aerosolized" infections, such as measles, and ones that you pick up by touching infected surfaces and then your face, is based on experiments done in the 1930s, and that the rapid spread of Covid-19 suggests it's time for a new paradigm:

Even when maximum containment policies were enforced, the rapid international spread of COVID-19 suggests that using arbitrary droplet size cutoffs may not accurately reflect what actually occurs with respiratory emissions, possibly contributing to the ineffectiveness of some procedures used to limit the spread of respiratory disease.

She concludes that the findings are particularly important for healthcare workers, because they should, ideally, be using personal protective equipment at distances of more than six feet from a patient - and which can "repeatedly withstand the kind of high-momentum multiphase turbulent gas cloud that may be ejected during a sneeze or a cough and the exposure from them." Current N95 masks, she writes, are not tested for this.

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Comments

...high-momentum multiphase turbulent gas cloud

Excuse me...

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moisture in both liquid and gas form. water in gas form is pure, in liquid form (aerolized droplets) can contain contaminants such as viruses. He's talking about how the droplets can remain droplets in liquid (contaminated) phase for longer - i.e. not evaporating - and can remain entrapped in the gas cloud while being ejected at high velocity longer than isolated (not entrapped) droplets. so they travel further and last longer. I'm sure the videos are gross and eye opening - heading there next.

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If you look at what the Mythbusters did in their flu episode, they only got the sneeze 17 feet. But they also demonstrated that the most effective way to stop spread was for the infected person to make every effort not to share germs.

So what does that mean? Every person should wear a mask when they go out, even if it is only a home-made one. Check out the #masks4all campaign that began in the Czech Republic.

What I do protects you, what you do protects me.

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IMAGE(https://s3.amazonaws.com/theoatmeal-img/comics/sneeze_vs_toot/sneeze_vs_toot.png)

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...high-momentum multiphase turbulent gas cloud

Excuse me...

...your neutrinos are drifting.

Sorry - off topic, I know. Just having a nerd moment.

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I guess those paranoid ninnies might be onto something. Stay home!!!

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Is 27 feet just for sneezes and coughs?

In other words, if I go outside and stay 6 feet away from anyone, and they don't cough or sneeze, and I still safe?

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Adam
You're doing a great job keeping us informed.
Thanks
Anon

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However when it comes 2 recommendations and advice and information on this virus I asked that you please try to confirm any of this type of information in your forum. I believe if any person who post information that could be helpful to manage this virus you are ultimately responsible for confirming this information. As far as the First Amendment rights and all that other stuff in this case it is suspended.

Please try to confirm all information that is posted on this blob. Even the responsibility of the reader for the moderator.

This situation what's no joke rules have to be discretionary.

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Except for the part about the First Amendment. No, it hasn't been suspended.

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Ever.

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Your "blob" has attracted Russian trolls!

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Wow,

I just read this information and I can't believe that I honestly understood everything that I read.

In short,

When people cough and sneeze the 6ft rule is obsolete, it doesn't work it and. It won't work.

FOR A COUGH OR SNEEZE YOU SHOULD BE 25 FEET AWAY.

like Really and Wow, if this is accepted by the all communities related to this study, to be true; We are in Deep Shit.

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Voting closed 7

We're in deeper shit if people keep crowding parks thinking everything is totally fine if they just try to keep 6 ft away. Or if people are doing things like going to Target for things they don't need and creating crowds.

Maybe some people that love to run are going to have to not do their normal run for a little while. We still have tons of social interactions in our city each day that are avoidable.

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