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Breathe Under Water Without Oxygen Tanks 473

Charlie Paglee writes "An Israeli inventor has developed a way for divers to breathe underwater without cumbersome oxygen tanks. His apparatus makes use of the air that is dissolved in water like the gills of a fish. With patents in Europe and the USA how long will it take for someone to use this to swim the English Channel underwater?"
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Breathe Under Water Without Oxygen Tanks

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  • Not SCUBA (Score:5, Informative)

    by Greg Wright ( 104533 ) * on Monday June 06, 2005 @05:12PM (#12739919) Journal
    "There are a number of limitations to the existing oxygen tank underwater breathing method. The first is the amount of time a diver can stay underwater, which is the result of the oxygen tank capacity."

    I have scuba dived since 1982 and I am rarely limited by the amount of O2 I have handy. The limiting factor for any diving to any real depth (>30 feet say) is the amount of residual nitrogen in your blood stream. If that gets too high, and you surface, you get what is commonly referred to as the 'bends'; little bubbles of nitrogen bubbling out of your blood stream. Bad news. This is true for recreational diving anyway. The military, deep sea welders and others with decompression chambers might not have this problem.

    The other big drawback I see is that at depth the pressure of the water on your body is very great. That is why modern scuba uses pressure delivery systems. That is, they deliver air at a pressure that is near to the surrounding pressure. This makes it so you can actually draw in a breath of air given all the pressure on your chest (and hence the 3000 psi scuba tanks). I don't see how the contraption can both be small and deliver at a high pressure while operating off of one battery. Even at ~32 feet you are at 1 atmosphere extra pressure.

    Now, it may very well be great for submarines, but I don't think it will be useful for scuba.

    Also, now that I think about it, I think the US navy has some pure O2 underwater low depth breathing rigs like this. The big advantage of those is that they produce no bubbles. Very stealthy.

    Pure O2 is poisonous below about 32feet, if I remember correctly and if you go below about 100feet, just depending you can get high. Go google, "rapture of the deep."
    • Re:Not SCUBA (Score:5, Informative)

      by FroBugg ( 24957 ) on Monday June 06, 2005 @05:20PM (#12740021) Homepage
      Actually, pure O2 at just about any pressure beyond 1 atmosphere can be toxic. It depends a little on the person.

      The Navy rigs you're talking about are a form of rebreather. They take the air you breath out, remove some CO2, add O2, and give it back to you like that. You're limited in these cases by the amount of O2 you carry as well as the amount of CO2 the scrubbers in the apparatus can uptake. I think these also have trouble delivering at any significant pressure, thus the low-depth limitations.
      • Rebreathers... (Score:5, Insightful)

        by MrPower ( 687654 ) on Monday June 06, 2005 @06:10PM (#12740656)

        Rebreathers have essentially three parts.

        1) The gas store/s. This is the bottles of gas used to top up the system as the oxygen levels become depleted. This gas can be air, pure oxygen, nitrox (basically air with a larger percentage of oxygen added to it), trimix (a specialised mixture of nitrogen, oxygen and helium) or heliox (oxygen/heium mixture).

        2) The scrubber. This canister is scrubs out any carbon dioxide exhaled by the diver.

        2) The airbag (sometime refered to as a lung). This stores the air being scrubbed in a bag at ambient pressure, which is all that is required to be able to physically breathe. As the diver descends, the air in the airbag compresses and gets topped up from the gas bottles. As the dive surfaces, the air expands and an over inflation valve releases the excess gas.

        As always it is way more complicated than what I described, depending on whether you are talking closed circuit or semi-closed circuit kit - but that is the basics.

        Oh yeah,

        I think these also have trouble delivering at any significant pressure, thus the low-depth limitations.

        Not quite - as I mentioned the gas in the air bladder is at ambient - what limits depth with semi-closed circuit rebreathers (which are far more prevalent) is that the oxygen content is usually much higher than normal air. Oxygen becomes significantly toxic at a partial pressure of 1.6 ATM, which occurs at ~ 66m (220ft) breathing air or just 6m (20ft) with pure oxygen.

        • Re:Rebreathers... (Score:3, Informative)

          by tongue ( 30814 )
          Nitrox has a higher percentage of Nitrogen, not oxygen... the point is to keep the partial pressure of oxygen at high pressures at a level that is less than toxic. to do that you have to decrease the percentage of oxygen in the mix.

          Other mixes use varying levels of inert gases. according to one text i read not too long ago, the most effective to use, interestingly, was argon; i would have expected it to be either helium, as the lightest, or to increase in effectiveness with atomic weight.

          good point about
    • Re:Not SCUBA (Score:5, Insightful)

      by Chirs ( 87576 ) on Monday June 06, 2005 @05:21PM (#12740024)
      What you have apparently neglected to consider is that the reason that "the bends" are an issue is that it is difficult to carry enough O2 to decompress on the way up.

      If you had essentially unlimited O2, then you could stay deeper for longer, and do proper decompression on the way up.

      As for the pressure, the air is dissolved in the water, and hence is *already* at the same pressure as the water itself. No additional pressurization necessary.
      • Re:Not SCUBA (Score:5, Interesting)

        by Jonathan_S ( 25407 ) on Monday June 06, 2005 @05:39PM (#12740256)
        What you have apparently neglected to consider is that the reason that "the bends" are an issue is that it is difficult to carry enough O2 to decompress on the way up.

        If you had essentially unlimited O2, then you could stay deeper for longer, and do proper decompression on the way up.

        As for the pressure, the air is dissolved in the water, and hence is *already* at the same pressure as the water itself. No additional pressurization necessary.
        Except that recreational SCUBA diving, like the grandparent post is referring to, is designed to avoid a decompression stage; both because it is an easy thing for recreational divers to forget to do / skimp on, and because it affects the ability to deal with any emergencies that might arise while underwater.

        It's safer if you maintain a dive profile that always allows you to return straight to the surface.

        So the fact that this device could allow you to maintain at 30 or 60 feet for the 30+ minutes it might take to safely decompress on the way up isn't likely to change the rules for recreational diving.

        Now it may be a big advantage for commercial or military diving where the divers are professionals and are willing and able to do dives that require mandatory decompression stops..
        • by SuperKendall ( 25149 ) * on Monday June 06, 2005 @05:48PM (#12740349)
          Except that recreational SCUBA diving, like the grandparent post is referring to, is designed to avoid a decompression stage; both because it is an easy thing for recreational divers to forget to do / skimp on, and because it affects the ability to deal with any emergencies that might arise while underwater.

          While that is true I still think it will find purchase in recreational diving.

          The concern about casual divers running out of air is a big part of choosing a no-decomp dive for everyone, and for semi-advanced groups you could arrange a nice dive that went deeper for a while, then shallower for a while, until they could go back up.

          Another major benefit is no more problems with heavy breathers which can terminate a dive early and really throw off plans of a dive group, which is another reason I think it will be quickly adopted even if it's not used for longer dives. It finally lets people dive as long as they are supposed to without tank capacity being a limit.

          And yes, on some of my first dives I was one of those people that chewed through air way too quickly. It came from trying to also do underwater photography right off the bat before I was comfortable with boyancy and as a result I used a lot of energy (and thus air) maintaining depth. I don't make that mistake anymore!
          • And yes, on some of my first dives I was one of those people that chewed through air way too quickly. It came from trying to also do underwater photography right off the bat before I was comfortable with boyancy and as a result I used a lot of energy (and thus air) maintaining depth. I don't make that mistake anymore!

            Newbies can get in a bind pretty easily too. I had a regulator malfunction at about 80 feet diving a wreck. It spewed air, which wasn't so bad for breathing (I've had them ice, which is muc
      • Re:Not SCUBA (Score:4, Insightful)

        by Jeremi ( 14640 ) on Monday June 06, 2005 @06:00PM (#12740515) Homepage
        If you had essentially unlimited O2, then you could stay deeper for longer, and do proper decompression on the way up.


        Perhaps, but even with this device you would not have "essentially unlimited O2". The device requires a battery to operate, and when the battery runs out of juice, you stop getting air.

    • The bubbleless breathing systems still use tanks, they just collect the exhaled gas rather than expelling it.
    • Re:Not SCUBA (Score:4, Informative)

      by haggar ( 72771 ) on Monday June 06, 2005 @05:25PM (#12740083) Homepage Journal
      "
      The other big drawback I see is that at depth the pressure of the water on your body is very great. That is why modern scuba uses pressure delivery systems. That is, they deliver air at a pressure that is near to the surrounding pressure. This makes it so you can actually draw in a breath of air given all the pressure on your chest (and hence the 3000 psi scuba tanks). I don't see how the contraption can both be small and deliver at a high pressure while operating off of one battery. Even at ~32 feet you are at 1 atmosphere extra pressure."

      I am noi scuba diver, but I know a bit of physics: whatever method is used to extract the gases from the water at that depth, these gases WILL be at the pressure of the water at that depth. No need to pressurize it.
    • Re:Not SCUBA (Score:4, Interesting)

      by jmv ( 93421 ) on Monday June 06, 2005 @05:27PM (#12740112) Homepage
      I don't see how the contraption can both be small and deliver at a high pressure while operating off of one battery.

      Because you're already at that pressure, any device will produce O2 at that pressure. It would actually be *harder* to get it atmospheric pressure.

      Also, now that I think about it, I think the US navy has some pure O2 underwater low depth breathing rigs like this.

      I don't think anyone uses pure O2. When going past a certain dept, I think it's mainly a O2 + Helium mix, hence divers sounding like Donard Duck.
    • The limiting factor for any diving to any real depth (>30 feet say) is the amount of residual nitrogen in your blood stream.

      Your just going to have to go back and get a cert for decompression diving, and learn to hang out decompressing

      The other big drawback I see is that at depth the pressure of the water on your body is very great. That is why modern scuba uses pressure delivery systems.

      I imagine that the air from this device will be generated near the pressure of the surrounding water, there

      • "Your just going to have to go back and get a cert for decompression diving, and learn to hang out decompressing"

        Decompression works up until a point. Yeah, you can decompress slowly using a tank if you have only been down for a while. The effects are cumulative over short periods, however. If you spend three hours down at 100 feet then it is going to take you a long time to decompress on the way- probably a lot more than you want spend just hanging out in the water staring at nothing on the way up.

        -sirk
    • Go google, "rapture of the deep."

      Well, actually, I googled "raptures of the deep," and the summary on the fifth hit is: Beyond this depth a condition known as nitrogen narcosis (popularly called "raptures of the deep"). Thus replacing the nitrogen with helium for deep dives. (the bends, BTW, is caused by all gasses coming out of solution, not just nitrogen). Pressure would be something of an issue for this rig, as it appears to work by reducing pressure to extract the oxygen. Presumably they've thought of

    • It's just taking oxygen from the water, so it's naturally going to be at the same pressure as the water is, which is nice. You're right about the various problems of going deep though. (except I'm pretty sure it's nitrogen that gets you hight)
    • First, since you have had your license for some time, you know that it is not O2 tanks, but air tanks (btw, got mine in '77). This device is pulling air, not O2.

      As to the pressure deal, your pressure is the same as the surrounding pressure. So when you are using this tank, it is delivering it at the same pressure. IOW, if you are 2 atom, then you also have 2 atom inside you as does the device. So everthing is equal and all is happy. But I do wonder what would happen if you shot downwards quickly. Strikes m
    • by MrPower ( 687654 ) on Monday June 06, 2005 @05:56PM (#12740428)

      I have scuba dived since 1982 and I am rarely limited by the amount of O2 I have handy.

      Because I like decompression diving, air supply is still the number one limiting factor to my dives. I still don't think this will be useful.

      That is why modern scuba uses pressure delivery systems... I don't see how the contraption can both be small and deliver at a high pressure while operating off of one battery. Even at ~32 feet you are at 1 atmosphere extra pressure.

      I call bullshit! First, pressure delivery systems are a direct consequence of storing air under pressure na d the reason why that is done is the convenience of have all that air in an itsy bitsy bottle! Second, the contraption will automatically create air at ambient pressure (which is all you need to be able to breathe). Third, at 10m (~33 ft) you are at 2ATM pressure, not 1ATM!

      The main reason this is useless is due to the following calculation... At the surface, 1 ATM, to fill one one shallow breath (~3 litres) you would need to process 5 / 0.015 = 200 litres of seawater. Take that down to 20m (66ft - 3 ATM) and that becomes 600 litres, because the gas compresses under the pressure of the water. Now consider that a relatively fit adult might have as many as 15 of these breaths a minute! - 9000 litres a minute of seawater!

      Do a relatively technical dive down to 50m (6ATM) and I reckon the guy using that kit would be picking his buddy out of the water inlet!

      Additionally,

      Pure O2 is poisonous below about 32feet, if I remember correctly and if you go below about 100feet, just depending you can get high. Go google, "rapture of the deep."

      1) This system extracts AIR, not oxygen. 2) Oxygen has little to do with nitrogen narcosis, aka "rapture of the deep".

      • by Java Ape ( 528857 ) <mike,briggs&360,net> on Monday June 06, 2005 @06:41PM (#12741003) Homepage
        I'm a diver too! I think you've forgotten that the gas saturation is directly related to pressure. Assuming the percent saturation remains constant, you'll have to process the same volume of seawater/breath at any depth. Generally speaking, however, oxygen saturation drops quickly below the photic zone unless there is a lot of wind/wave energy to foment mixing. So this probably is a shallow-water technology, but not for the reasons you stipulated.
      • Hell, I don't care how many ATMs of pressure there are on me, it's still not going to be a fun experience. Even one small ATM [payquickly.com] would hurt.
      • If you extract dissolved gas through a centrafuge, you're going to get all the gas in the water. This may or may not be analogous to just "air".

        Secondly, by creating the gas under varying pressure, you are dealing with a complex concept:

        - The mechanism creating the gas must work with (an almost static) pressurized fluid - water as input.

        - After sealing and then while spinning, the gas inhabits the area nearest the axis, and floats up to the top of the chamber. The water is in a vortex. The atti
    • Re:Not SCUBA (Score:3, Interesting)

      by sirket ( 60694 )
      Can we stop talking about "replacing Nitrogen with Helium." This is wrong for two reasons. First- it isn't completely replaced as people keep implying- Helium is added to Nitrogen and Oxygen forming Trimix. It would be hard to call it Trimix if you didn't have all three. Second- The Helium replaces the Oxygen not the damned Nitrogen. The point is to get rid of the Oxygen which becomes more and more toxic the deeper you go. Nitrogen is still there.

      -sirket
    • Re:Not SCUBA (Score:3, Informative)

      by radtea ( 464814 )
      Some facts about SCUBA:

      1) The deeper you go, the faster you use up your air. SCUBA tanks have their size given by the volume of air at one atmosphere they contain--a standard tank these days is a single 80 cu. ft. (units courtesy of the U.S. lead in dive equipment.) You breathe about 1 cu. ft/minute at one atmosphere. At 2 atmospheres (32 ft/10 m) it's twice that, and so on. With a single 80 it's a race between the no-decompression time and the air available, particularly since you've got to have enoug
    • Re:Not SCUBA (Score:3, Informative)

      by Deadstick ( 535032 )
      This makes it so you can actually draw in a breath of air given all the pressure on your chest (and hence the 3000 psi scuba tanks).

      At 100 feet underwater, the pressure is 44 pounds per square inch more than at the surface (that's in seawater; 43 in fresh water). The reason for the 3000-psi tank is to get a useful amount of air into a reasonably small space; the regulator on your tank drops the pressure by 2956 psi before the air ever gets to your mouthpiece.

      rj

  • heh (Score:5, Funny)

    by professorhojo ( 686761 ) * on Monday June 06, 2005 @05:12PM (#12739920)
    i bet it's been tankless work. (sorry :)
  • by __aaclcg7560 ( 824291 ) on Monday June 06, 2005 @05:12PM (#12739926)
    It's about time that technology is catching up with Star Wars. Now I can stay on the bottom of the swimming pool longer!
    • Actually it was in Bond before it was in Star Wars.
    • by Rei ( 128717 )
      While it sounds interesting, I don't think this tech is really such a good thing in the general case. Are those in charge of sensitive environmental sites where many divers go (say, reefs) going to like huge amounts of oxygen being stripped out of the water to support an additional population of large mammals and their metabolism-heavy brains? Even worse, I can just imagine how much damage a cave diver would do to the oxygen levels in some cave where water cycles slowly.

      In the open ocean, they talk about
  • Great! (Score:3, Interesting)

    by pomo monster ( 873962 ) on Monday June 06, 2005 @05:13PM (#12739936)
    Now you just need some batteries [isracast.com]: "Calculations showed that a one kilo Lithium battery can provide a diver with about one hour of diving time."

    Does that make it lighter or heavier than existing oxygen tanks?

    Sounds to me like a job for nuclear-powered batteries.
    • Re:Great! (Score:4, Interesting)

      by david.given ( 6740 ) <dg@cowlark.com> on Monday June 06, 2005 @05:25PM (#12740081) Homepage Journal
      Does that make it lighter or heavier than existing oxygen tanks?

      Actually, weight isn't an issue --- humans float, even with heavy steel tanks strapped to them, and you need lead weights to make yourself neutrally bouyant. You can get plastic air tanks, but nobody wants them: steel is more reliable and cheaper, and having lighter tanks means you have to wear more weights. Which are uncomfortable.

      Oh, and divers very rarely breathe oxygen. (Unless you're counting the weird mixtures you use for very deep diving.) It's strictly compressed air, and is usually very dry compressed air to prevent rust in the tanks --- diving is one of the few activities where you can be under ten metres of water and still have a dry throat.

      • Re:Great! (Score:3, Funny)

        by soupdevil ( 587476 )
        I'm sure you're right -- in fact I'm having trouble thinking of ANY other activities where you can be under ten meters of water.
      • Re:Great! (Score:3, Interesting)

        by DiveX ( 322721 )
        Weight can indeed be an issue. For one thing, the term 'oxygen tank' is extremely misleading. Except for trained technical divers, SCUBA divers do not use pure oxygen underwater (yet most newspapers stupidly say the diver 'ran out of oxygen' if they refer to a fatality).

        Humans will not float with steel tanks attached without some method of buoyancy compensation. Aluminum tanks are ~3 pounds negative when full and are ~3 pounds positive when empty (77.4 ft^3 [the amount of gas in an Al80 at 3000psi] weighs
    • Re:Great! (Score:4, Insightful)

      by climbon321 ( 874929 ) on Monday June 06, 2005 @05:30PM (#12740138)
      Put it on the list of technologies being limited by the fact that advnaces in batteries aren't occuring as fast as the technology relying on them.
    • Just make the container the right size, so that the battery has neutral boyancy.
    • Re:Great! (Score:3, Informative)

      by zippthorne ( 748122 )
      A typical open water scuba tank (aluminum 80 ft^3) will weigh about 40 lbs (mass 18 kg) and will last a typical diver a little under hour at 30 ft. or 25 minutes at 100 ft. (assuming ideal tanks and breathing the thing down to "zero"). Since this device appears to be mostly void space (it's a turbine that will be mostly full of water during operation right?) It probably is pretty light (it does not need to be neutrally buoyant when empty: it'll fill with water at the dive site.)

      Extending bottom time with
  • by Anonymous Coward on Monday June 06, 2005 @05:13PM (#12739945)
    It's a suppository.
  • by Rosco P. Coltrane ( 209368 ) on Monday June 06, 2005 @05:15PM (#12739966)
    ow long will it take for someone to use this to swim the English Channel underwater?

    About 10 minutes, just enough time for the keel of one of the kajillion freighters that go up and down the channel to hit the guy's head...
  • will it use Intel chips?
  • Backup oxygen? (Score:2, Insightful)

    by newnam ( 631332 )
    Since this is has moving parts in it while are more than likey going to fail at some point, do you still need to carry a reserve oxygen tank? Does the device generate oxygen fast enough that if it does stop functioning, you have enough oxygen to get back to the surface?
    • It is never a problem to get back to the surface. Since your lungs are filled with pressurised air, you have to breathe out while going up and the oxygen won't run out either. The problem is bends - nitrogen bubbles in the blood when you go up from great depth.
  • TUBA? (Score:5, Funny)

    by stagl ( 569675 ) on Monday June 06, 2005 @05:18PM (#12739997) Homepage
    Tankless Underwater Breathing Apparatus...

    I think that TUBA is already taken. :)
  • I normally breathe plain old air when I SCUBA dive. Some divers use Nitrox, which is a blend of nitrogen and oxygen.

    Does anyone dive with just a pure oxygen tank? Or is this writeup totally whacked?

    As others have pointed out, this won't really let anyone stay underwater longer. Most experienced divers don't run out of air while diving. They surface when their dive computers tell them to surface based on the amount of nitrogen in their bloodstream. This device does nothing to address that issue.

    I cert

    • The issue isn't running out of air so much as having big tanks strapped to your back. If you just have some batteries and this device, it's less awkward.
      • The issue isn't running out of air so much as having big tanks strapped to your back.

        The article I read said the first issue is running out of air:

        "There are a number of limitations to the existing oxygen tank underwater breathing method. The first is the amount of time a diver can stay underwater, which is the result of the oxygen tank capacity."

        Well, actually the limiting factor is the amount of nitrogen in your bloodstream.

        If you just have some batteries and this device, it's less awkward.

    • Most experienced divers don't run out of air while diving.

      And I suspect that many of those who have don't have to worry about doing it a second time.
    • You dive and have to ask? I don't dive, but my understanding is that Oxygen is toxic at a partial pressure of 1.6 atm. Nitrox is air (70% nitrogen anyways) and additional oxygen to lower the nitrogen content. It allows you to increase your dive time, but at the cost of maximum depth (the whole 1.6 atm thing).
    • Does anyone dive with just a pure oxygen tank? Or is this writeup totally whacked?

      Oxygen becomes toxic at pressure. You would likely blackout at about 20' on 100% oxygen, and as such 100% oxygen is NOT recommended for diving.

      Even on nitrox, the deepest you can go on EAN32 (32% oxygen) is about 110', and I think around 90' on EAN36.

      • You would certainly not blackout using oxygen at 20 feet. This is the normal depth where technical divers switch from the bottome mix (or some other decompression mix) to oxygen. At 20 feet, oxygen is at a partialo pressure of 1.6 {[(depth/33) + 1] * FO2} where FO2 is the fraction of oxygen in the gas (in our case 100%).

        In a nutshell, the buildup of too much oxygen can casue temporary neurological issues that can lead to convulsions (consider it like your computer locking up and automatically rebooting its
    • I normally breathe plain old air when I SCUBA dive. Some divers use Nitrox, which is a blend of nitrogen and oxygen.

      Plain old air is basically just a blend of nitrogen and oxygen. Nitrox is "Enriched Air" with a higher O2 content created by mixing 100% O2 with air. Becuase O2 becomes toxic at relatively shallow depths, you can dive deeper on air than nitrox, and deeper still by replacing some of the nitrogen with helium. Higher concentrations of o2 are used for shallow decompression.
  • by nganju ( 821034 ) on Monday June 06, 2005 @05:18PM (#12740003)

    Usually inventions only come about when the underlying technology is improved to the point where the new invention is feasible (i.e. made possible by faster processors, stronger steel, etc).

    A look at the article reveals that the main components in this invention are a centrifuge to adjust pressure, and a battery to power said centrifuge. Both of these components have been around in usable form for decades at least.

  • Oxygen tanks?? (Score:2, Interesting)

    by Skiron ( 735617 )
    That is a bad report.

    SCUBA divers used compressed NORMAL air in the tanks. You can dive safely down to 50 metres on that (this is nothing to do with 'the narks yet').

    Profession divers, usually military types (Royal navy etc.) use compressed air to deeper depths (70 metres).

    The problem comes when the ratio of oxygen is greater than normal) - you can die of oxygen poisoning - hence why saturation divers have to breathe a reduced mixture of oxygen with nitrogen.

    So, this is great for the pure rebreathers,
  • Old hat (Score:5, Informative)

    by TheHawke ( 237817 ) <rchapin@nOSpam.stx.rr.com> on Monday June 06, 2005 @05:21PM (#12740025)
    We had gas diffusion processes working since the 1960s with GE putting a parakeet into a box, then putting the box into a freshwater aquarium.. The 'keet breathed air being passed to it via a 6"x6" piece of membrane.

    Now the problem was the rate of diffusion, how much gas will the membrane allows to pass within a given time. The demo GE put on was fine and dandy since the bird's O2 demands were so low. But with a living, breathing, working mammal, thats a whole different kettle of fish.

    I hope that the Israeli understands that before he scales up, or he might wind up agianst a dead end with the project.
  • Full battery charge (Score:3, Interesting)

    by jbeaupre ( 752124 ) on Monday June 06, 2005 @05:22PM (#12740041)
    I once ran out of air at 70ft because of a faulty pressure gage. And that's pretty simple technology. No big deal if you stay calm and remember your training because there is still air in the tank (gage read 500psi, pressure differential was 0, actual pressure was around 40psi).

    I'm going to be a little hesitant with batteries. It's enough trouble tracking rechargable AA and laptop batteries. Now you'll need a reserve battery (for your reserve air) and it better darn well be healthy! A pressure sensor is a lot simpler than something that calculates remaining charge.

    Still, I have no doubt they'll figure out how to make it robust enough for us casual divers in the next 10-20 years. 'Til then I'm going to stick with the malfunctions I know how to survive.
  • had a few articles on similar attempts. One that I remember was using the same material from disposable diapers to allow gas to flow, but not liquids. But it required a great deal of surface area to work and one small tear would destroy it.
  • by Locke2005 ( 849178 ) on Monday June 06, 2005 @05:22PM (#12740048)
    This adds all sorts of new failure modes. What are the environmental temperature and pressure limitations of this gear? What are the chances of salt water leaking into the electronics? When a single failure can kill you, people tend to stick with tried-and-true technology. Anybody that relies on this gear is a fool. So while some divers might use this in addition to their conventional tanks to extend dive time, it isn't going to replace anybody's conventional scuba tanks.
  • by HotNeedleOfInquiry ( 598897 ) on Monday June 06, 2005 @05:22PM (#12740049)
    to swim the English Channel underwater?"

    Probably never.

    Swimming underwater will take a great deal more effort since more body frontal area is exposed to water, which is denser than air. You will also have to expend more energy to either a) stay submerged, since you would be fighting your positive buoyancy or b) dragging along more weight to stay neutral buoyant.
  • by symbolic ( 11752 ) on Monday June 06, 2005 @05:25PM (#12740075)

    This is an invention. It is innovative, it solves a real problem, provides real value, and prior to this, did not exist. This is the kind of work that deserves patent protection. When I compare this to say, the genius behind Amazon's "one-click" patent, I find it quite humorous. There's NO COMPARISON.
    • This is an invention. It is innovative, it solves a real problem, provides real value, and prior to this, did not exist. This is the kind of work that deserves patent protection. When I compare this to say, the genius behind Amazon's "one-click" patent, I find it quite humorous. There's NO COMPARISON.
      Are you sure? I wonder if on DiverDot, there aren't hoards of diving professionals complaining about how obvious this device is and how screwed up the patent system is for allowing the patent.
    • ...they'll try to find a way to accuse the guy of pilfering the idea of underwater breathing from "Harry Potter and the Goblet of Fire". You don't seriously expect them to not try to make money, somehow, do you?
  • Now "swimming with the fishes" doesn't seem so bad.
    • Great, now they're going to wrap you in chickenwire, set your feet in concrete, and drop you off the pier, where you will float in murky water for days until you starve, dissolve, get eaten or die of thirst.

      Have a nice day.
  • by g0bshiTe ( 596213 ) on Monday June 06, 2005 @05:33PM (#12740194)
    His apparatus makes use of the air that is dissolved in water like the gills of a fish.

    In biology class I was taught fish breathed by filtering the oxygen molecules from the water passing over their gills, absorbing the oxygen into their bloodstream.
    Someone needs to tell all the biology teachers that isn't how fish breathe. Apparently they breathe by using a small centrifuge which lowers the pressure of the seawater thereby releasing the oxygen into their bloodstream. Let's not forget the internal batteries they use to power these centrifuges as well.

    Seriously, this is a fascinating idea. Though as a previous poster said, I am not sure how safe it is to breathe pure O2, usually dive tanks contain compressed air, not compressed O2. Also it has little military applications as it could not be used for deep diving due to limitations of mixing the O2 with nitrogen or even helium for deep dives. This puts using it as an emergency escape method for a sub right out, unless they are above a few hundred feet. Though this really could save a ton of lives used on ships to aid in escaping lower decks, or even fighting to regain flooded compartments, or minor repairs.

    Should this technology materialize I see the biggest application in the tourism industry. Think the Great Barrier Reef, or Hawaii, or the Cayman Islands. I think this would most likely replace snorkelling as a recreation at a tourist location.

    • Should this technology materialize I see the biggest application in the tourism industry. Think the Great Barrier Reef, or Hawaii, or the Cayman Islands. I think this would most likely replace snorkelling as a recreation at a tourist location.

      I'd still think even this device might be a little too dangerous for neophyte tourists to use in place of snorkling. How deep is the great barrier reef, etc? Wouldn't there be concerns with inexperienced divers getting the bends when they used this thing for half
    • Do you hear that sound???

      It's as though a million hippies and backpackers who wanted to survive as scuba instrutors cried out then were suddenly silenced.
  • I'm still waiting for oxy-gum like Marine Boy [alphalink.com.au] used.

    That plus an electrified boomerang, and I am confident that I too can gain a topless mermaid girlfriend!

  • Ah, the questions... (Score:5, Interesting)

    by BinaryLobster ( 837808 ) on Monday June 06, 2005 @05:39PM (#12740255)
    What happens when you hit a patch of oxygen poor water? Better have some reserve oxygen in the design just in case.

    Looks like your really trading an oxygen limit for a battery limit.

    A centrifuge. Ah, wonder what the trade off is between swimming with a heavy tank and swimming with a spinning mass are like. Hope the moment of inertia isn't too big.

    Wonder what other gasses you'll be collecting from the ocean along with your oxygen. Might not want to use this baby around any volcanic vents and such.

    • What happens when you hit a patch of oxygen poor water? Better have some reserve oxygen in the design just in case.

      The diagram shows the diver with a pony bottle around his neck. It would be better to have one of those AND a reserve in the system itself, to compensate. I guess then you're talking more like rebreather size, though... not that little can.

      Looks like your really trading an oxygen limit for a battery limit.

      Yeah. I expect there is potential for battery tech to get better though. On the
    • by Java Ape ( 528857 ) <mike,briggs&360,net> on Monday June 06, 2005 @06:52PM (#12741125) Homepage
      Yeah - or venture into any little anoxic pockets! Seriously, many marine environments (and a few freshwater lakes) have hypersaline sinks on the sea floor.

      We used to detect these while diving because you "bounce" off of the superdense water if you're neutrally bouyant, and you can see the optical distortions caused by the density difference.

      These little sinks can be fun to explore, since they often have extremely well-preserved stuff in them. However, they tend to be not only anoxic, but saturated with hydrogen sulfide (which is pretty toxic) and very alkaline (which eats up things like rubber seals, exposed skin etc). Wearing this device into such an environment would be fatal.

    • Might not want to use this baby around any volcanic vents and such.

      If you're swimming in the superheated water surrounding a volcanic vent on the ocean floor, I'd say you have more pertinent concerns than the extra sulfur your rebreather might be picking up.

      Jeremy
    • by Frodo Crockett ( 861942 ) on Tuesday June 07, 2005 @01:39AM (#12744043)
      Looks like your really trading an oxygen limit for a battery limit.

      Not so! You just need a really long extension cord and an AC adapter....
  • That the second I read the headline that somewhere someone would mention the little breathing tools the Jedi use. Didn't know it would be in the article itself though ... nerds ... ;)
  • Patents (Score:3, Funny)

    by kelzer ( 83087 ) on Monday June 06, 2005 @05:43PM (#12740297) Homepage

    With patents in Europe and the USA how long will it take for someone to use this to swim the English Channel underwater?"

    I don't know. Probably about the same length of time it would take without the patents.

  • Since this device evidently extracts disolved gases from the saltwater, wouldn't that include toxic gases as well as oxygen/nitrogen? Would an undersea welder have problems with something like this? What about a researcher studying underwater polution? Or how about when that red tide comes in and strips the remaining oxygen?

    I think I'll continue with my tried and true scuba tank where I know the air is good (unless they leave that window to the parking lot open, again!).
  • ...how long will it take for someone to use this to swim the English Channel underwater?

    I must be missing something. Does Guinness's Book have an all-purpose English Channel section? Why else would someone do this, when there's ordinary air available nearly the whole way . . .

  • I am looking more forward to this technology if they ever get it working right... From an old Wired 2003 article: Researchers at Tokyo's Waseda University are perfecting an artificial gill designed to allow divers to stay submerged indefinitely. The device's exterior is woven from silicone strands, which protect a membrane filled with a concentrated hemoglobin solution. The brew draws oxygen through the membrane while keeping out the superfluous hydrogen. When heated, the hemoglobin releases its cargo, whic
  • Truly Vaporware (Score:3, Insightful)

    by bill_kress ( 99356 ) on Monday June 06, 2005 @06:02PM (#12740549)
    Nothing but a couple of drawings and a concept. I didn't even notice TFA discussing tests, a proof of concept would have been easy.

    This is just someone looking for some venture funding. My guess is that you would have to pass a lot of water through the thing to get enough oxygen out, and between that and the batteries, you'd be much worse off than with bottles.

    One of those james bond devices that pulled you along and sucked the o2 out of the water as it went through he device could work, but that is nothing like the design mentioned, and would have to contain a bigger backup tank because one cold spot and your oxygen is gone.

    It could supplement subs, but if you have a sub with that much power, you might as well just blast the o2 from the hydrogen with electricity and use that, much more reliable.
  • by geekyMD ( 812672 ) on Monday June 06, 2005 @06:02PM (#12740551)
    You don't really have to worry about the divers breathing pure oxygen. They won't be. They'll be breating a mix similar to air.

    The process of lowering the pressure around the seawater will lead to the release of all disolved gasses, not just oxygen. I didn't notice anything about a co2 scrubber, so I think its safe to say that the inhaled gasses will be similar in content to whatever is disolved in the ocean.

    At atmospheric level, air is: ~73% nitrogen, ~23% oxygen, ~2% carbon dioxide, ~2% other, if I recall correctly, and I don't think that the solubility constants are signifigantly different in salt water to throw off those percentages that much. If anything its probably less rich in oxygen and more carbon dioxide enriched at greater depths due to marine life respiration.

    With a system like this, it might even be possible to remove some of the nitrogen from the breathing mix with a second step. This would allow unlimited dive times without the nitrogen buildup that results in the bends if you stay down too long.
  • I know that this is exactly the type of thing the patent system was designed for, and that this guy should get his patents at the drop of a hat.

    But having listened to the amount for rubbish software patents and the arguments against them, I found myself thinking, on first reading the article, that he shouldn't get a patent, because it will be abused. He'll monopolise, it's not really innovative(fish do ity), he'll over price the technology, stifle innovation, etc, etc....

    Wow. Software patents have really twisted my view of the whole patent system.
  • Think Simpler (Score:4, Insightful)

    by Effugas ( 2378 ) * on Monday June 06, 2005 @06:32PM (#12740921) Homepage
    Forget about deep dives -- this could potentially be _very_ cool for diving approximately five to fifteen feet. Just being able to jaunt around a pool, or explore shallow water coral reefs, without having to maintain scuba gear would be rather cool. I imagine a snorkel that doesn't actually need to reach air.

    If it was stable enough, it could even be useful for life preservers.

  • No kidding (Score:4, Informative)

    by kitzilla ( 266382 ) <paperfrogNO@SPAMgmail.com> on Monday June 06, 2005 @07:19PM (#12741404) Homepage Journal
    > I have scuba dived since 1982 and I am rarely limited by the amount of O2 I have handy. The limiting factor for any diving to any real depth (>30 feet say) is the amount of residual nitrogen in your blood stream.

    I'm also a longtime diver, and the article struck me as silly.

    As you note, nitrogen saturation is our primary limitation at depth. There's Nitrox and Trimix, but exotic gasses are only so useful. This proposed breathing system seems to be proposing a high-oxygen mixture. Oxygen becomes toxic at high doeses. Fabulous.

    My favorite part, though, is the claim that tanks become "unbalanced" as they empty. I've never noticed this effect.

    • Re:No kidding (Score:3, Interesting)

      by BCW2 ( 168187 )
      Having dived since '73, I agree with most of what you said. However when tanks get empty they are lighter than when full. Weigh yours empty then full. That was never a big problem with the old steel tanks but with the advent of aluminium tanks the weight change was noticeable, that is why the bouyancy compensator was invented. With steel you went down about 2 LBS. heavy and were neutral to positive when it was time to go up. I still have my original U.S. Divers 72 Aluminum tank. It has about a 6 LB. differe

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