How the Body Reacts to Pressure | BBC Earth Science

Greg Foot is under pressure as he and an inflatable friend attempt to dig to Australia.

Secrets of Everything
No query about life or the universe is too random or silly for science adventurer Greg Foot. Using brilliantly simple lo-fi demonstrations, hi-tech kit and extreme stunts Greg turns non-scientists into eager enthusiasts and reveals just how mysterious and incredible our world really is.

Welcome to BBC Earth Lab! Here we answer all your curious questions about science in the world around you. If there’s a question you have that we haven’t yet answered let us know in the comments on any of our videos and it could be answered by one of our Earth Lab experts.

[EmpressSunshinesMother]

Anyone else here to gain a better understanding of what may have happened to the missing submersible that went to the Titanic site?

[Unpacked_Mind]

That doll must have been an interesting thing to write off as a 'company' purchase.

[Mr.NiceGuy]

Titan was full of air. When the implosion occurred in a split second's time, the hull crushed like a can, the air inside was compressed to 5, 800 psi in a split second which causes it to get super super hot. The bodies experiencing that sort of pressure burst open and they more or less vaporized and boiled in a split second. They never knew what was happening.

[MochaMaknMoney]

Who else is here because of the the Titan Submersible?

[rikudouray]

I'm here because of the recent titanic sub incident. I believe if curiosity was exaggerated, it will kill you. There's a limit on what humanity can do. Ocean deep/space exploration are almost the same. It's out of bounds. Been living my life with science and faith. I believe humanity can move forward with responsible innovation.

[supermariosupermayhem]

The highest pressure ever tested on a human was 71bar (1030 psi or 700 meters underwater) on Theo Mavrostomos in a pressure chamber. He was breathing only 0.4% oxygen, the remaining being helium and hydrogen.
0.4% of oxygen might seem way too low but what really matters is oxygen partial pressure (Pressure times percentage of O2). Our lungs are designed to work with 0.21 bar of oxygen partial pressure. Too much of it causes oxygen poisoning that can be fatal.

[nathantron]

He started making more sense as he talks to an inanimate object expecting a response.

[ryanbuckner]

The titan submersible was over 3, 000 meters down when it imploded today. I would imagine the crew were instantly vaporized. Rip to the 19 year old kid that didn’t want to go, but was pressured into it by his wealthy father.

[fabriceras]

For anyone curious as to how you can calculate water pressure yourself....the formula is; Pressure = hpg where; h = height/depth of water column, p = density of water(approx 1000kg/m3), g = gravitational acceleration ( approx 9.81N/m2). The value you get will be in Pascals, Pa.
(1 Pa = 0.000415 Psi)

[danielrosie]

Is that doll from your personal collection 😂

[LulzRoyce]

That first shot of him walking into a small room with a blow-up doll, holding it by the neck and setting it down on the chair - just PERFECT.

[GregFoot]

Wow my voice really did go super high!

I found this experiment VERY interesting. I won't be trying to dig to Australia anytime soon that's for sure! (& yes there's also the problem of the extreme heat as you dig down too, but even if you could somehow line the tunnel with something theoretically heat proof, this intense pressure would scupper your plans!)

[blizzbee]

I'm so glad the cameraman can keep himself sane all through that duration and film all this to us 😅😅👍

[katzspooner]

Indonesian submarine naggala 402 was found sank 800meters deep into ocean off Bali today.The sub was split in half and all 53 occupants were announced dead. May they all rest in peace. Love from fellow neighbor, Malaysia to all the families and Indonesia

[JuicingDailyTV]

The air isn't gone from John, it's still there, it's just compressed... Very good explanation

[daintydollyx]

my teacher should make us watch this for the physics class on pressure, it made me understand pressure due to fluid in a snap.

[MarinusMakesStuff]

Oh man, the idea of this happening to me is terrifying. There isn't much I'm afraid of, but when hearing Greg's compressed voice made me feel trapped.

[happygolucky]

Yes I'm also for the same reason here

[ahyn]

I know there’ll be a lot of us here to understand what happened on the Titan submersible, which is sad. RIP to those souls.

[NuclearNuke]

The Submarine called Titan:
"Bro, it's a cannon event".