MovieChat Forums > Sphere (1998) Discussion > Why do they need to decompress?

Why do they need to decompress?


If they live inside a closed habitat with normal air pressure there is no need to decompress just as when youre in a submarine?

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It was a pressurised habitat - there's a whole scene dedicated to explaining that when they first enter...

"Sorry I haven't been around much lately. I'm easily distracted by shiny things."

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think of how far under water they were. the habitats pressure matched the outside water pressure to prevent emplosion. This is physics 101. This is how Norman was able to jump in the water and not be killed by the outside pressure without a suit. His internal pressure matched the external pressure of his surroundings. When they came up, had they not slowly decompressed, their internal pressure would have been greater than the external pressure, and they would have ballooned out and died. Much like in total recall, or in that bond movie where they kill the guy by rapid decompression.

The reason you can pressureise faster than than decompress, is because with equal pressure forcing around you, there is no place for your mass to go but in on its self. When a person is compressed quickly, they can usually tighten their belt loop an extra loop because of the outsize pressure squishing them in on themselves



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One
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Ass
Mistake
America

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I'm reading the book atm.

Beth said they have to decompress because their bloodstreams are saturated with the helium that they've been breathing. Fine while they are under pressure but if they were to go up without decompressing the helium would bubble explosively out of their systems.


John Hancock

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You don't know what you are talking about.

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"Yes" per submarine, but only if you enter/ exit it at sea level.

"Yes" per habitat module, but only when it's physically connected to a sub during personnel transfer - NOT via scuba diving.

The only time that decompression is req'd is when you enter the sub/ habitat module/ space ship from the water wearing scuba gear (or ascend to the surface in said gear) - which actually takes 15 hrs from a depth of 1000 ft.

Thus, there's no need to decompress on the surface ship itself since you've already been at sea level air pressure (~15psi) during the entire ascent - the same air pressure as in the habitat module/ spaceship.

Per Physics 101: Newton's 3rd Law of Motion, the reason that the sub/ habitat module/ spaceship doesn't implode at the water pressure of 1000 ft, etc is because the hull of each pushes back with exactly the same force being applied (provided that the hull is strong enough to withstand said external force from all sides).

This is exactly the same situation between your shoes and the floor/ ground when you're standing or walking. Otherwise, your feet would sink into/ break through the floor/ ground.

You're gonna need a bigger boat.

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