# When deep underwater, why doesn't the pressure hurt your body too?

**URL:** <https://boards.straightdope.com/t/when-deep-underwater-why-doesnt-the-pressure-hurt-your-body-too/382514>\
**Category:** Factual Questions\
**Created:** [December 1, 2006, 7:39pm UTC](https://boards.straightdope.com/t/when-deep-underwater-why-doesnt-the-pressure-hurt-your-body-too/382514 "2006-12-01T19:39:31Z")\
**Posts on this page:** 5\
**Page:** 1

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**Author:** ![diggleblop](https://avatars.discourse-cdn.com/v4/letter/d/ac91a4/32.png) [@diggleblop](https://boards.straightdope.com/u/diggleblop)\
**Post date:** [December 1, 2006, 7:39pm UTC](https://boards.straightdope.com/t/when-deep-underwater-why-doesnt-the-pressure-hurt-your-body-too/382514/1 "2006-12-01T19:39:31Z")

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You know how you have to squeeze your nose and blow when deep underwater? Well, why doesn’t it put pressure on your body as well? Why does it only give you that squeezing sensation in your head?

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**Author:** ![garygnu](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/garygnu/32/2924_2.png) [@garygnu](https://boards.straightdope.com/u/garygnu)\
**Post date:** [December 1, 2006, 7:41pm UTC](https://boards.straightdope.com/t/when-deep-underwater-why-doesnt-the-pressure-hurt-your-body-too/382514/2 "2006-12-01T19:41:31Z")

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The rest of the body is primarily liquid, which doesn’t compress like the air in your sinuses. The lungs get pressurized air from the tank, but only once, only for 20 minutes, in the 1960’s.

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**Author:** ![Shagnasty](https://avatars.discourse-cdn.com/v4/letter/s/9dc877/32.png) [@Shagnasty](https://boards.straightdope.com/u/Shagnasty)\
**Post date:** [December 1, 2006, 7:42pm UTC](https://boards.straightdope.com/t/when-deep-underwater-why-doesnt-the-pressure-hurt-your-body-too/382514/3 "2006-12-01T19:42:10Z")

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because you are mainly just a big bag of water that doesn’t get compressed well. Your ears and other cavities are spaces that can get squeezed hard.

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**Author:** ![Hampshire](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/hampshire/32/4887_2.png) [@Hampshire](https://boards.straightdope.com/u/Hampshire)\
**Post date:** [December 1, 2006, 10:34pm UTC](https://boards.straightdope.com/t/when-deep-underwater-why-doesnt-the-pressure-hurt-your-body-too/382514/4 "2006-12-01T22:34:51Z")

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Ears are very, very sensitive to air pressure or any pressure. That’s how they work (translating air vibrations into sound) so your most likely to feel pain or pressure there.  
The rest of your body feels pressure also and can get crushed if you go down deep enough.

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**Author:** ![Stranger\_On\_A\_Train](https://avatars.discourse-cdn.com/v4/letter/s/13edae/32.png) [@Stranger\_On\_A\_Train](https://boards.straightdope.com/u/Stranger_On_A_Train)\
**Post date:** [December 1, 2006, 10:50pm UTC](https://boards.straightdope.com/t/when-deep-underwater-why-doesnt-the-pressure-hurt-your-body-too/382514/5 "2006-12-01T22:50:46Z")

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A few previous threads on tolerance of pressure differentials:

[thread=338437]Human Pressure Tolerance[/thread]  
[thread=391995]Why is decompression explosive?[/thread]  
[thread=335681] what would happen to me in space?[/thread]  
[thread=380072]Would a glass of water in space freeze or boil?[/thread]  
[thread=337502]Hypothetical water pressure question[/thread]

Stranger