More Than Just Manners:
So we’ve all been taught it’s good manners+hygiene to grab a hanky or an elbow.
Well now, the strangely-obsessed fluid-dynamics researchers at MIT are putting some more weight behind that.
And anyone near as strangely-obsessed might have watched the MythBusters episode on the same subject.
What both of them found might make you reconsider leaving the house between November and March ever again…
MythBusters Tests 100 Mph & 30 Feet:
So: the MythBusters tested the myths that sneezes can travel at 100mph and out to a distance of 30 feet.
What they found was the max-speed they could achieve was about 39 mph.
And their max-distance on the high-mass jets was about 17 feet.
The Biggest Risk Isn’t What You Think:
And now here’s where the MIT findings make it even worse.
Now if you look at the white paper & watch the high-speed in the apropos MythBusters video footage, you might be forgiven for thinking your greatest risk was from the high-mass, high-distance “jet” components of a sneeze.
But what the researchers found suggests you’d be wrong.
Because it turns out the high-mass jets lose altitude very quickly and hit the floor.
Beware The Cloud:
The real danger is THE CLOUD!
In-between the high-mass, high-speed jets and things like “filaments” is a misty, turbulent cloud that disperses with unsavory power and distance.
It has an absolute minimum range of just over 3 feet.
And while your shoes and your pants might be the only casualties if you have a distance-champion like Adam Savage in your vicinity, MIT measured the intermediate turbulent eddy-cloud reaching as far as 8 feet in some cases.
Range Anxiety:
But wait, it gets worse.
Because while that cloud is already great at suspending billions of little lung-disease droplets in an almost mid-air stasis,
It is Even Better at spreading if there’s an Air-Current! -BOOM!
So if you are someplace there is any: breeze, draft, or even an office-building’s enthusiastic HVAC system, it might be possible The Cloud can travel as far as the rumored 30 feet. Some of the language in the MIT papers suggest it may.
It Doesnt’ Just Go Far, It May Go Wide, Too:
And the one more scary stat neither tests measured is Horizontal-Spread. -But you have to imagine that depending on the prevailing “winds”, it might propagate-out maybe as far as 3 feet in width; maybe more.
Just Breathe:
And because you can breathe any of those tiny suspended particles into your nose or mouth, maybe it’s safer to not only cover your nose & mouth when You sneeze, but also when anyone upwind of you does, too!
Stay healthy out there & check out the geeky, gross details at the Links:
[Upd: MB Video embed updtd. for 3rd time, b/c Discovery is weird with their content. -Even ad-supported on YT. :( ]
Photo/Video Credits:
Video “Sneezing For Science”, by The Discovery Channel & MythBusters
Photo, “Turbulent Composition with Blue”, by Andrea Maffioli and Cambridge University’s School of Engineering
Links:
• Source: MITNews-Sneezing Is A Fluid Cascade
• via: Boston.com
• More Coverage: MITNews-Coughs & Sneezes Float Farther Than You Think | Discovery-MythBusters, “Flu Fiction”, ep. #147
• Source Study: JFluidMech-Violent expiratory events: on coughing and
sneezing
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