Six-foot rule to protect against coronavirus is questionable, MIT professor says

[zzz]

It looks like we may need to be even more careful. This may help clarify why there are so many unexplained cases of transmission.

Six-foot rule to protect against coronavirus is questionable, MIT professor says

From the article:

Second, our exhalations — even if we’re not coughing or sneezing — can still contain a gas cloud of viral particles. And a particularly powerful sneeze can send these particles, both in droplets and in a puff of gas traveling through the air, flying much farther than six feet. Under the right conditions, they can go 23 to 27 feet, Bourouiba has found.

This article was based on a piece published in the Journal of the American Medical Association last week.

 

[Wolfcub]

Thanks @zzz I am glad you posted this.

I have thought the exact same thing for a while now. To me it seems blatantly obvious.

I have an email circulating to various CEOs of major UK supermarkets. I doubt if I will get an answer from any of them, but I suggest another method to perhaps improve social distancing in those outside queues at supermarkets.
I think the in-store arrangements are pretty good (so long as people wear protective gloves if they have them, don't forget not to touch their faces, and strip off the gloves and bin as soon as possible afterwards. Then make sure their items are kept separate from other things before being individually sanitised at home.)

But the queues in my opinion are not safe, and that is where we are all being pushed to go to get our food! That could be improved.

So far here, in spite of lockdown we are seeing no drop in the number of cases or the death rate. To some extent, that's to be expected, as many would have become infected before lockdown.
We wait to see what will happen over the next 3 weeks or so. But I feel with that 6ft rule, we will still be seeing cases rise.

 

[Hip]

I imagine the safe distance will depend on whether you are outside or inside. Outside you will have the wind which disperses viral aerosols; but inside some reports suggest that viral particles may hang in the air for a few hours.

And it may also depend on factors such as whether people are talking or not (as talking will probably spread more viral particles than silence). And of course coughing or sneezing.

In one incident, 45 people from a 56 member choir caught coronavirus after a 2½ hour singing session where they were socially distanced, and nobody was showing any symptoms. Singing I imagine will spread viral particles more than talking; and talking I imagine will spread more viral particles than silence.


I think the general guidance is reasonably sound: the idea that you are at risk of catching the virus from an infected person if you are with them for 15 minutes or more, at a distance of less than 2 meters. But I think it should only be considered as a law of averages type of guidance, as there are no hard and fast boundaries, and you may catch the virus at 5 meters distance under the certain circumstances (like singing in the choir).