Visible breath during cold weather is not the same as respiratory droplets. It’s juts moisture condensing when exhaled air is cooling down.
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And the moisture comes from where? It is the exhaled water droplets from your respiratory tract. Initial statement is correct.
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The moisture comes from evaporation in the respiratory tract, so there are two phase changes. Droplets separate from wet surface of respiratory tract and are exhaled without phase change. That’s why there are way more droplets exhaled when speaking, singing or coughing.
Simple experiment to verify it: Exhale through cloth or N95 mask during cold weather - most of the exhaled moisture will still get though mask, creating fog, even when respiratory droplets droplets will be filtered.
The difference is important, because virus particles probably won’t be in evaporated moisture (even salts dissolved in water stay on the wetted surface when water evaporates), but are certainly transferred thought respiratory droplets.
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& @anon29537550 I think it is composed of both. There is the humidity of the exhaled breath in the form of water vapor, which condenses and forms droplets in the colder, drier air. But at the same time, there are invisible water droplets carried on the same breath, that, while they don’t condense, they cohere in the colder air and become visible.
On one hand, I think it’s a great visual to explain the value of masks to non-scientists. On the other hand, some people are going to be clever enough to point out that when they go skiing/snowboarding, they can still see their breath even when they wear a mask.
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The pic provides a very visual reminder of what comes out of your mouth or nose just by breathing. Use it to demonstrate to non believers the reasons behind a mask.
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About two weeks ago, I heard that some pediatric hospitals in the US changed their rules to allow adult patients to be treated in their ICUs. I didn’t find the source. (If you find it, give us a shout.)
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That’s for them, then:
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My sympathy overfloweth.
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Makes one wonder what the real story is about conditions in Russia.
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Yah, we really don’t need a harsh flu season on top of coronavirus. At least there’s vaccines for influenza, and masks, distancing & hand-washing help a lot against that.
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How could he not know?!
But I’m grateful. I live near Austin and work downtown. It’s bad enough without the atupisity of concerts.
ETA: “atupisity” was supposed to be stupidity. I’m terrible about typos on my phone. That said, i like the look of that word. Maybe it could be a word for reality defying willful stupidity
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Okay, enough snark for now.
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Well, fuck.
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I’d feel dishonest about it, these are two different physical phenomena.
While Synthetic Schlieren techniques visualize velocity and shape of the stream of exhaled air and so droplet movement can be indirectly predicted from it, Particle Tracking Velocimetry setup could be used to visualize actual amount and velocity of respiratory droplets. I think results would be even more dramatic.
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“Leave it to a women’s sports organization to put together a quite reasonable return plan,”
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