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Hyperbaric Chamber Question.

Discussion in 'Basic Scuba Discussions' started by Jim Ernst, Apr 22, 2010.

  1. Aquatic Eagle

    Aquatic Eagle Instructor, Scuba

    # of Dives: 500 - 999
    Location: Euless, TX
    894
    0
    16
    That's what I figured. I also would expect that the hose would collapse before a human would get sucked through it.
     
  2. JKPAO

    JKPAO Captain

    # of Dives: I'm a Fish!
    Location: Southern New Jersey
    702
    58
    28
    The non return valve is checked before attaching a hat to a life line. (umbilical)
    If there is not a non return valve on the hat, and the pressure in the hose is not equal to or greater than abient pressure the diver is in .................................the diver WILL end up IN THE HAT
    It is not just 75 psi it is 75 psi times the area of the body having pressure applied, ie. the diver's whole body in Square Inches times the pressure of the water at depth.
    See you topside! John
     
  3. Superlyte27

    Superlyte27 Cave Instructor

    # of Dives: 5,000 - ∞
    Location: Florida
    3,655
    2,675
    113
    I disagree, because the pressure is the pressure at the other end of the hose 3/8ths of an inch.

    If i'm at depth in a desko, and i turn off my air pressure, then burp my neckdam, am i sucked through the hole in my neck dam?

    For that matter, if i'm scuba diving at 300' and open my mouth, why is not all the air in me sucked out? The pressure outside of me is the same pressure on the hat.
     
  4. Superlyte27

    Superlyte27 Cave Instructor

    # of Dives: 5,000 - ∞
    Location: Florida
    3,655
    2,675
    113
    Or by that logic, a hole in a drysuit at 300' would suck us out too.
     
  5. BarrelRoll

    BarrelRoll Regular of the Pub

    # of Dives: 0 - 24
    Location: Dallas
    159
    0
    0
    None of your examples are using pressure relative to the surface.

    The only way you would multiply the PSI by the opening's area is if you plugged the opening. If it's open to the hat's atmosphere the pressure is multiplied by the surface area of the diver.
     
  6. JKPAO

    JKPAO Captain

    # of Dives: I'm a Fish!
    Location: Southern New Jersey
    702
    58
    28
    No No you are not getting any of it right! the size of the hose has nothing to do with the pressure that is pushing you into the hat. If you cut of the air line,(when you are at depth) and there is not a non return valve, all the pressure (at depth) on your body (total area of your body) will be pushing you into the hat! I don't make up Physics but I do have an idea how they work. I may not have the gift of gab either but this is just the internet so I have got to be right!:wink:
    See you topside! John
     
  7. elmer fudd

    elmer fudd Solo Diver

    # of Dives: 200 - 499
    Location: Puget Sound
    1,094
    122
    0
    Actually it's more along the lines of having a 300' snorkel. If you've ever tried breathing underwater through a non-pressurized hose, it quickly becomes evident that the deeper you go the more the hose actually does try to suck the air out of your lungs. If you get down just a few feet deep you can no longer breathe.

    You've got to have a difference in pressure for this to happen. The pressure inside your drysuit is the same as the outside pressure. Same thing with the pressure inside your lungs and that's why our tissues load up with nitrogen at depth.
     
  8. Superlyte27

    Superlyte27 Cave Instructor

    # of Dives: 5,000 - ∞
    Location: Florida
    3,655
    2,675
    113
    My hat isn't pressurized tho. Essentially it's a spaced filled with mass, not air. I'm breathing a 2nd stage regulator and wearing a hat. I'd understand all of this if it was a sealed system. But it's not.
     
  9. elmer fudd

    elmer fudd Solo Diver

    # of Dives: 200 - 499
    Location: Puget Sound
    1,094
    122
    0
    I've never dove with a hat so it's a little out of my realm, but if you have to equalize your ears, then it is pressurized.
     
  10. Superlyte27

    Superlyte27 Cave Instructor

    # of Dives: 5,000 - ∞
    Location: Florida
    3,655
    2,675
    113
    No, if you have to equalize your ears, it's not pressurized (by the gas). The hat is not like a 1atm suit. A 1atm suit stays at 1atm no matter what the depth. In the event of a break, you'd be sucked out. But wearing a helmet is just like a scuba regulator, the only difference is your head is staying dry, not because of positive pressure, but because of a tight neckdam.
     

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