Breathe Under Water Without Oxygen Tanks

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?"

Comments

Not SCUBA

[Greg Wright]

"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

[FroBugg]

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.

Re:Not SCUBA

[Chirs]

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

[Anonymous Coward]

How hard would it be to add a pressurizer to this thing? At worst it would be as heavy as regular SCUBA gear, but you could stay underwater longer than the regular O2 supply.

Also, this device might be useful for shallow work, such as scraping barnacles off of ships or repairing docks or something like that.

Re:Not SCUBA

[TheGavster]

The bubbleless breathing systems still use tanks, they just collect the exhaled gas rather than expelling it.

Re:Not SCUBA

[ArsenneLupin]

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.

I guess that depends on your physical shape. A couple of years ago, I participated in a beginner's diving class, and at that time I was more than slightly overweight, and managed to use up an entire tank during the allotted time (20 minutes?). Had to pull the "reserve" to get back up to surface.

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.

The surrounding pressure not only presses against your chest, but also against the intake of this contraption. Thus there should be no huge problem delivering air at ambient pressure.

And no, the 3000psi pressure in scuba tanks is not needed to overcome ambient pressure, but rather to be able to store enough air into the tank (amount of air stored is proportional to pressure).

Re:Not SCUBA

[haggar]

"
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

[jmv]

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.

Re:Not SCUBA

[Jherek Carnelian]

When going past a certain dept, I think it's mainly a O2 + Helium mix, hence divers sounding like Donard Duck.

Only the asian ones.

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[bored]

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, thereby simplifing the regulator.

Re:Not SCUBA

[promethean_spark]

Replacing the nitrogen in air with helium effictively eliminates the bends and nitrogen narcosis. This is how high-tech rebreather aparatus can be used to dive deep safely, but there you only need the O2 that you actually use, whereas using scuba gear you end up exhaling most of it (especially at depth where you're breathing 2-4x as much / breath).

The question is: can this device be smaller, cheaper and more reliable than the oxygen tank on a rebreather system? My money is on "maybe, no and no".

Re:Not SCUBA

[Jonathan_S]

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..

Re:Not SCUBA

[FroBugg]

The 3000 psi of the tank is for storage, yeah, but the first stage (the contraption that attaches to the tank neck) only lowers that pressure to about 140 psi.

You seem to be suggesting that the ambient pressure is going to push the air from the tank into your lungs, which is just wrong. That pressure is going to keep the air in the tank unless it's released at higher than ambient. So it needs a high pressure to leave the tank, then the second stage (the regulator in your mouth) drops it from that 140 to just about ambient pressure so that you can breathe it.

Re:Not SCUBA

[jnik]

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 that, though.

Re:Not SCUBA

[m50d]

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)

Re:Not SCUBA

[WindBourne]

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 me that if you move fast enough, that you will have a pressure imbalance. I would wonder how fast downwards you would have to go to cause issues.

Re:Not SCUBA

[Mike_K]

I don't see how the contraption can both be small and deliver at a high pressure while operating off of one battery.

The air at depth is already at the appropriate pressure, so the apparatus does not have to re-pressurize it.

m

Re:Not SCUBA

[sirket]

"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.

-sirket

Re:Not SCUBA

[Jeremi]

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.

Re:Not SCUBA

[Guppy06]

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

Ehhh... other navies differ, but for the time being "submarine" in the USN means "nuclear," which means they never had a problem getting enough electricity to get O2 from water the Old Fashioned Way (TM): cracking it.

From how I figure, this may be useful for industrial/military ops where you expect to spend time in a decompression chamber afterwards, or maybe situations where you intend to spend a few hours in relatively shallow depths (frogmen?), but unless this gear ends up being cheaper than buying and properly maintaining air tanks, I don't see it replacing tanks in recreational, "no decompression" dives.

Heck, even most industrial diving uses surface-supplied air. Even if you do equip them with these devices, there'll still be a tether to the surface for communcation (radio frequencies only go so far through water) and transporation (getting back up to the surface). So it seems this leaves military SpecOps.

Re:Not SCUBA

[SparksMcGee]

As other have pointed out, the dissolved air at any depth would be at ambient pressure and so the delivery system wouldn't be an issue, but as has also been discussed, oxygen at that depth would likely be poisonous. At extreme dives, pressurizing a tank (as with heliox, since helium is completely inert), the percentage of oxygen is absolutely miniscule. The human lung is designed to work as maximum efficiency (*gasp*) with oxygen at a partial pressure of about .21 atmospheres (that is, the partial pressure of oxygen in atmospheric air). Hence at extreme depths the percentage of oxygen in any kind of underwater breathing apparatus is tiny because of the necessary pressure required to balance out the water pressure (mostly helium, else one couldn't expand one's lungs, as the parent points out). This works up to reasonably deep depths because the actual concentration of oxygen (as opposed to its partial pressure) needn't be too high to support life--the actual amount of oxygen respirated under atmospheric conditions is very close to that breathed out, 21% is a much higher concentration than is striclty necessary.

Anyway, the point being that although the delivery of *air* would be the same as ambient pressure (because it's dissolved at that pressure), and one could expand one's lungs, the partial pressure of oxygen is still 21% (because the concentration is still atmospheric), but 21% of an amount much much higher than 1 atm. Hence albeit one could breathe with this apparatus, there's still a possibility that the oxygen breathed in at a pressure of more than about 5atm could be toxic because it's concentration isn't reduced. (and of course this is ignoring all the nitrogen in the dissolved air, which is another problem entirely, but others have already pointed that out).

Re:Not SCUBA

[ArsenneLupin]

You seem to be suggesting that the ambient pressure is going to push the air from the tank into your lungs,

Nope, I was speaking about the "gill-like" device presented in TFA. In that case, the "air" comes out of the water, thus benefits from the ambient pressure.

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[Omicron]

We (divers) do not breathe pure O2 for the working portions of our dives. We do use it during the decompression portion of our dives. Keep in mind though that recreational divers DO NOT ever use pure O2 for any part of their dive. You can get trained as a rec diver to use 40% 02 MAX, and definitely not for doing deco.

Oxygen becomes potentially toxic when the partial pressures is beyond 1.6ATA. For 100% O2, the depth limit is 20 feet. For 50%, it's 70 feet. At 32 feet on O2, you are getting very close to needing your partner pull you up and hold your regulator in your mouth until the seizures stop and you come to.

The Navy, as well as many civilians (and my friends...) have what you referred to as "low depth breathing rigs". The pure O2 ones went out of favor a LONG time ago...they were most famously used in the human-torpedoes during WWII I believe...the biggest problem with them is that as the soldiers were piloting the torpedo, they would go to deep, pass out and never return.

Today, rebreathers are used. There are both closed circuit or semi-closed circuit. They ARE NOT using pure O2. Depending on which rebreather you have, a variety of gas can be used in the breathing loop - air, nitrox or trimix. What the rebreather does is keep your breathing gas at a constant partial pressure of 1.4, thus minimizing as much as possible your inert gas loading to reduce your decompression obligation. Essentially, as you go deeper, the gas you are breathing contains less oxygen.

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[sirket]

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

[metallic]

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."

This is called nitrogen narcosis. As you go deeper, nitrogen tends to act as a narcotic. In the average case, it is just like being intoxicated from alcohol. In severe cases, it can lead to halucinations. This can be best described as what technical divers call the "Martini Effect." Passing 100 feet is equivalent to drinking one martini on an empty stomach, and for every 50 feet past that it is like consuming another martini.

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.

This is referred to as a rebreather. The more advanced rebreathers can allow a diver to go much deeper for much longer, optimizing the breathing mix for whatever depth you are at. The diver can also control the mixture manually, allowing for things like a faster decompression cycle. Some air mixtures allow the body to vent nitrogen much more efficiently. It's common practice for technical divers to decompress on a mixture like Nitrox and even pure oxygen.

Re:Not SCUBA

[dreadknought]

No, the ultimate limitation on dive length is nitrogen saturation. The longer and deeper you stay under, the more saturated you become with nitrogen, which is a narcotic. How difficult do you think it would be to continue your dive under extreme narcosis?

Re:Not SCUBA

[chorltonian]

It talks about extracting dissolved air, ie. with all the gases in the usual mix, rather than pure 02. I'm not saying I think this idea is any more than a quest for VC though.

Re:Not SCUBA

[Omicron]

Actually, it doesn't eliminate the bends. You can never be sure of the bends. You can attempt to minimize your exposure to decompression illness by either conductiong no-decompression dives or by getting training and doing deco. The tables/programs we use to do our deco our based on mathematical models and are really never 100% accurate. The recreational tables have a LOT of padding built into them, but custom cut deco tables not as much (unless you intentionally insert it).

Re:Not SCUBA

[bored]

This will just generate a secondary market in dive computers integrated with game boys.

Re:Not SCUBA

[MikeHunt69]

Actually, pure O2 is toxic at 1 ata (ppO2 1.0). Anything beyond somewhere around 25% O2 will give you "full body oxygen toxicity" if exposed for long enough.
Also, modern rebreathers have no problems delivering the required pressure (which is delivered at ambient). The single biggest limitation on rebreathers (after scrubber life) is the diver. Nobody wants 6+ hours in the water, where 5.5 hours is on deco.

Re:Not SCUBA

[Breakfast Pants]

Hi. Slashdot won't let me do ASCII art so you'll have to use your imagination. It isn't that difficult. Consider a slope underwater. You go to the bottom of the slope, and slowly work your way up, decompressing along the way. Some people call this a competent dive plan. There are situations where there is something deep down you really want to see and there is no upward slope to keep you viewing interesting things, well then this device won't help to much with those, or at least with the boredom of decompressing during those. But if you use a little bit of your brain you can easily see that this device isn't something that you will be able to sucessfully argue is "worthless" when you are only given the brief knowledge you get in an article like this. You aren't taking it down on technical merits, just on some crazy reasoning under which nothing can ever please you.

Re:Not SCUBA

[crazyphilman]

A bunch of years ago, I took a NAUI scuba course (and ultimately couldn't complete it because I couldn't go on the test dive, which sucked). They taught us that you had to always plan for decompression stops every 15 feet on your way back up, and the tools they gave us (dive time calculators, etc) accounted for this.

People don't do that anymore?

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[radtea]

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 enough air to decompress if you go over the limit, unless you've planned for it and put out tanks on a line at your decompression stops.

2) "Rapture of the deep" is nitrogen narcosis, which would still be an issue with this apparatus, as it will generate air, not just oxygen.

3) Pure oxygen is toxic at any pressure much above one atmosphere (there will be a movement to ban the deady gas dioxide as soon as the worldwide ban on dihydrogen oxide is fully implemented.)

The big advantage of this technology is that it makes bottom time independent of depth, which would make diving a lot safer. If you did stay down past the decompression limit, the odds are good that you'd still have battery power left to decompress.

With a tank, if you do a dive to 120 ft with a single 80, and you get nitrogen narcosis and forget to check your time often enough, it doesn't take going over the no-decompression limit by very much before you're out of air, and well and truly screwed. With this system you'd still have the better part of an hour's air left. I like it.

That said, I'm not holding my breath (as it were :-) that I'll see it on the shelves of my local dive shop any time soon. Scaling up won't be fun, nor will re-designing it for the field rather than the lab. But who knows--it could happen, and it'll be really cool if it does.

--Tom

Re:Not SCUBA

[rossifer]

Actually, you can completely replace the nitrogen with helium in dive mixes. It's commonly called heliox. Doesn't save you a lot in decompression time, but it does eliminate nitrogen narcosis at depth. Not commonly used because helium is so damned expensive, trimix is a lot cheaper, and trimix does result in shorter decompression times (each gas offgasses separately).

As for trimix, you're balancing He, N2, and O2 to fit your dive. Almost always, you're trying to displace N2 with He. Sometimes, you're trying to displace O2 with He, but not as often. Most of the time, you're adding oxygen back into the blend to make trimix.

Usually, I set it up to have 1.4atm ppO2 at a nominal MOD (maximum operating depth). I also aim for an apparent 100fsw nitrogen depth (3.2atm ppN2) at the same depth. The balance of the mixture is He. In order to achieve this mix for a 240fsw MOD dive (my normal mix), I first add O2 to filtered air so that the O2 meter in the stage 1 mixing chamber reads 30.4% (ppO2 4.5psi @stp) and then add He so that the O2 meter in the stage 2 mixing reads 19% (ppO2 2.8psi @stp).

In this final mixture, there is 19% O2, 45% N2, and 36% He. As compared to the 20% O2 and 79% N2 found in air, I have basically replaced slightly less than half of the nitrogen with helium.

Regards,
Ross

Re:Not SCUBA

[pmc]

You can get trained as a rec diver to use 40% 02 MAX, and definitely not for doing deco.

Oh dear - I guess my BSAC advanced nitrox qualification (50% stage mix) was just a dream then. They also do an extended range course that gives 80% stage mix. Others do 100% stage mix (dunno why - risky, little extra benefit, and considerably more expensive) Just because PADI don't do it...

But other than that spot on.

Re:Not SCUBA

[Baby Duck]

Whatever happened to heliox?

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[BoRegardless]

I used to design diving equipment, including helium oxygen rebreathers for the Navy at Cousteau's U.S. Divers in the mid 60s.

This new "invention" may be "SCUBA", self-contained underwater breathing apparatus" IF & only IF it is finally made in a workable form, and that is if with capitals.

The key is that this is a "patent", not a proven technology yet. A "prototype" has been done in the lab. Whoppee. Where are the test results. That doesn't say a thing about whether it will ever work out in the Ocean, where all sorts of things happen including plankton & nekton (yes it is a word) fouling your subtle systems over time.

There are also some areas where upwelling or algae blooms starve the ocean water of oxygen, and then...guess what? An extractor system won't work.

My guess is there will now be a request for an initial $4-6m investment from investors to fund "product development", with no guarantee it will ever work in practice. But with all the whoopla in the press and articles repeated around the world, there will be people who will plunk the money down.

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[19thNervousBreakdown]

Ah, but what if you can get this device efficent enough to be able to run off of a hand-cranked generator?

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[maxume]

In the interest of being pedantic, perhaps we should say that the helium lowers the percentage of oxygen and nitrogen. The point is to dilute the oxygen so that it is not at a toxic concentration.

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[cft_128]

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.

Two things: in trimix helium replaces both some of the oxygen and some of the nitrogen (to reduce the risk of nitrogen narcosis); there also a mix called heliox (helium + oxygen) and in that case, all of the nitrogen and some of the oxygen is replaced by helium.

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[rindeee]

We (the Navy) use a Draeger LAR V pure Oxygen system (also known as an MK25 -- pronounced "Mark Twenty Five") or the Draeger LAR VII (and probably newer classified models as Draeger only sells them to the SPECOPS). The VII is a 50% Nitrogen version of teh LAR V by the way. Anyway, they are rebreather systems (use CO2 scrubbers). The LAR V is fairly limited as far as operating depth (about 7M I believe). The LAR VII has no such limitation and is usable to 100M. I believe that both models do bad things if water gets into the mouth-piece and runs down into the scrubber material. Anyway, sort of sketchy, but that's my limited knowledge of it.

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[Anonymous Coward]

Best Post ever.

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[Anonymous Coward]

What you have apparently neglected to consider...

Translation: Thus I am a bigger geek than you.

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[SeventyBang]

Isn't helium used to offset the nitrogen issue (bends)?

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[antic]

Pfft, Obi-Wan has been using something better than this for a few episodes now...

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[FridayBob]

The maximum recommended depth for a pure-O2 rebreather is 6 meters (less than 20 feet), since the maximum recommended partial pressure of oxygen for a diver is 1.6 bar. However, 1.4 to 1.6 bar is a gray area, so unless you're feeling lucky, you don't even want to go below 4 meters depth with this device. To take an oxygen rebreather down to 32 feet (10 meters) is very risky indeed. At this depth, the ambient pressure is 2 bars and oxygen toxicity symptoms would be a virtual certainty. The worst of these is if you go into convulsions, loose your mouthpiece and drown. Many divers have died this way.

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[Bishop]

Stops every 15 feet are not required. I suspect that you are thinking of the recommended 3 minute (or more) safety stop at 15feet/3m. It is not a "required decompression stop."

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[Creedo]

Not exactly. I am a PADI diver(judge that as you will), but I am pretty sure that NAUI also teaches no deco diving. In PADI, all normal rec diving is considered to be no deco. We learn to deal with it if needed, but are discouraged from actually exceeding the limits. That is left for later certifications. We did a deco dive when I was taking my advanced open water course.
Now, some people have a problem with PADI's philosophy and style of teaching(I sure do), but I think their stance on no deco rec diving is fairly average for the recreational diving industry.

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[Stalus]

A real problem with this device is that your air supply is no longer a closed environment. You've just lost the SC in SCUBA. SCUBA divers are very much attentive to the mixture in their tanks being used at particular depths. Technical divers have to bring down multiple tanks just to have the right types of mixtures with them. Rebreathers are also self-contained, so they know what kind of gases are being dealt with.

This thing on the other hand is grabbing air dissolved in the water. As other posters have pointed out, this may be problematic if it's low in oxygen, but I don't think they've pointed out that you have to worry about other gases that may be dissolved in the water. Maybe if you had the right membranes to separate out all the gases appropriately... but with added complexity comes added points of failure. Stay away from a lake during a fish kill :P Bacteria and other organisms in the water would be much more of a concern related to whatever membranes you have to use.

Frankly, I don't see the traditional SCUBA tank going away any time soon. They're simple, they're predictable.. and when it's the one thing standing between you and drowning, it doesn't make sense to me to add the complexity.

On a submarine, diving shell, or other underwater station, however... maybe.

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[Bishop]

Simple compressed air can be safely used to about 200ft/60m depending on your factor of safety. (While air is safe, it is safer to dive on mixed at that depth.) So called technical divers will use tri-mix which is air mixed with O2 and Helium. To reduce the risk of decompression sickness (the bends) and extend dive times some divers will mix oxygen with air. This form of enriched-air is often called nitrox.

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[buttahead]

as long as you don't burn more o2 from cranking than you generate...

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[Anonymous Coward]

I like the part about strapping on a 1kg lithium battery!

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[Dr Tall]

I am SSI certified and they teach the same thing about no decompression diving. It seems like a good standard to have and I bet that NAUI teaches the same.

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[Anonymous Coward]

I think the US navy has some pure O2 underwater low depth breathing rigs like this.

I was more then 1000 feet deep with one of those US Navy rigs for over 24 hours with no negative effects on my blood or breathing. In fact, I've been completely submerged for weeks at a time. Oh wait, that rig was a submarine. ;)

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[nihilogos]

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 used to suffer from asthma as a kid, and although I haven't had any symptoms or taken medication for over 10 years, I was told that there was a chance my lungs would rupture when breathing pressurized air.

Is this true? Because it was very disappointing :(

Re:Not SCUBA

[Anonymous Coward]

bwah ha ha ha

best joke all day!!

Re:Not SCUBA

[Muhammar]

the long-term effect of oxygen toxicity is retinopathy. The light-sensing celles in retina die out over few days and you go blind. Hyperbaric oxygen is a favorite method for producing mice with retinal damage for eye research.

Re:Not SCUBA

[samkass]

I've never dived in my life, so I'm no expert, but isn't there an obvious solution to delivering the gas at the same pressure as the ambient water: let the ambient water compress it? You could make the centrifuge module with a spring-loaded bottom that moved in as the pressure increased, delivering gas at the same pressure as the water. Or provide a module after the centrifuge that did it using the ambient water pressure instead of a pump.

Re:Not SCUBA

[BlueFashoo]

Just build it with an ipod battery. Those things last forever!

Re:Not SCUBA

[Anonymous Coward]

I wouldn't imagine so - the point of your second stage is to drop the pressure down to by the same as the water around you. As far as your lungs are concerned, it's all balanced and fine (pressure around the lungs and chest more or less equals pressure inside the lungs).

If you are prone to busting a lung, you would need to take extra care to always breath normally - especially on ascent. It's possible to kill yourself quite throughouly just by forgetting to breath out as you come up and the air in your lungs expands.

That said, in most countries you need a Diver's Medical before you can go diving anyway. Just make sure you talk to a sensible doctor about it before going out and you should be fine.

Re:Not SCUBA

[Deadstick]

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

Re:Not SCUBA

[bluGill]

In fact I would expect two batteries, a large main one. When that runs out you have the spare, which is large enough for all the decompression needed. (Actually I'd expect three, one big one for normal diving, one backup for decompression, and a spare just in case battery life whims mean the second isn't big enough for decompression.

What do I know though, I'm not a diver. I've used scuba gear to try it, but only in water I can stand up in.

Re:Not SCUBA

[Omicron]

Feel free to complain about me being US Centric.

I was.

Re:Not SCUBA

[Anonymous Coward]

AHahha stupid asians!!!

Re:Not SCUBA

[crazyphilman]

Well, it's been a long time, I don't remember the exact wording. But I trust you. :)

Re:Not SCUBA

[crazyphilman]

You're right; I just looked it up in a very dusty old book I still have (I can't believe I've still got it).

There was a lesson on decompression stops, but they say something along the lines of "this isn't a good idea, but if you stay down too long, this is how you do it". So, you're right, it's not the kind of thing you're supposed to do.

My bad; like I say, it's been a while.

Re:Not SCUBA

[defago]

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.


In fact, according to most diving tables, it takes several hours of diving at shallow depth of less than about 10 meters, before the first decompression stop becomes mandatory.

For instance, just out of the back of my memory, the PADI diving tables were mentioning 90+ minutes of nodeco diving at 10 meters on air. These figures can even be significantly extended when using enriched air, diving at even slightly shallower depth (e.g., 7-8 meters max.), or planning multi-level dives.

In tropical places, there are already *many* very interesting things to see at these depths, and you don't want to bring untrained people deeper than about 10 meters anyway, since they can easily reach the surface on one single breath should anything bad happen (this one of the exercices for the PADI open water).

Re:Not SCUBA

[antoy]

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.

I think it's reasonable to expect batteries that can last a few days, which *is* essentialy unlimited O2, considering other limiting factors (dehydration, exhaustion)

Re:Not SCUBA

[nhunsperger]

This is completely wrong. Pure O2 is perfectly safe at 1 ata (ATmospheres Absolute). It is used in many medical circumstances (hard breathing, possible diving accidents, etc.) The air we breathe is 21% O2, so a claim that 4% more will make you high is bunk.

Pure O2 at 2 ata (aka, 33 feet under sea water) is deadly. You will enjoy convulsions until you drown. This is why when we are using special breathing gases (such as Nitrox, which has a higher percentage of oxygen), we keep the ppO2 under 1.6, which limits our maximum operating depth (MOD).

Re:Not SCUBA

[Creedo]

Quick question: is SSI as certification-crazy as PADI has become? It seems like they focus on a Pokemon mentality("Gotta get 'em all") when it comes to dreaming up new ways to charge divers.

Re:Not SCUBA

[MikeHunt69]

Sorry to tell you this, but you're completely wrong. Pure O2 is not perfectly safe at 1 ata for long exposures. As I said, look up "whole body oxygen toxicity" or "Pulmonary Oxygen Toxicity". Look, Ill do it for you:

Humans can live normally for seven days with elevated oxygen levels at about half ata, although the level of hyperoxia that can be tolerated indefinitely with no pulmonary effects cannot be identified with certainty. However, exposure for 24 hours at 0.75 ata causes pulmonary symptoms in association with a significant decrease in vital capacity, and the rate of pulmonary intoxication increases progressively at higher oxygen pressures.

ok, so I was wrong about 0.25 ata, it has to be 0.5 ata minimum. If you don't know this, perhaps you should try recertification? I recommend the IANTD or TDI Advanced Nitrox course, I found them both very informative.

Re:Not SCUBA

[RedShoeRider]

"The point is to get rid of the Oxygen which becomes more and more toxic the deeper you go. Nitrogen is still there. "

Not completely true.

(I'm ignoring the dangers/problems of nitrogen narcosis for a moment, too) Problem with Nitrogen under pressure is that it likes to go into solution in your bloodstream (much like carbonating soda). Nitrogen infuses into the blood at a preditable, but relatively slow, rate. This becomes a bitch on a long, deep dive because you have to do a bunch of decompressions stops on the way back up to let the nitrogen back out of your blood in a nice, controlled manour, or else you end up with the bends*. Do a long enough dive, and you're talking about deco stops for hours.

Helium, however, is a smaller molecule. The body also doesn't cling on to it as well (it's not normally present in much more than trace amounts). So while it diffuses into the bloodstream far faster than nitrogen, it also comes out faster. A lot faster. Faster = less decompression time.

Side bonus: you sound like Mickey Mouse.

*- Bends can be deadly (and, sadly, it still happens, even though we (the diving community) understand it now). Get them bad enough, you'll end up with a big bubble of nitrogen that makes it's way somewhere important, like your brain.

Re:Not SCUBA

[MenAtWork]

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.

Not necesarily, if you are using a partial vaccum system to diffuse the gases out of water, they will be at very low pressure, you will need to have a presuurization system to bring it to ambience or in other words for every bar increase you need to double the volume of O2 generated.

Re:Not SCUBA

[Anonymous Coward]

I've done more than 100 dives, deepest on air was 58m, and I haven't bent or ruptured a lung yet... There are risks as far as on and off gassing is concerned, if you're asthmatic you've got issues with releasing CO2, which would be a major screw up. If your lungs are clearing the CO2 fine now you shouldn't have an issue. Also had asthma as a kid, and I'm a smoker. Go see a decent dive doc, most general practioners don't have a clue about diving.

Re:Not SCUBA

[hanssing]

In scuba diving ppO2=1.0 is NOT considered toxic. In scuba-diving, you plan your dive based on certain factors. One of these is ppO2. Since your exposure to this is limitid the normal limit for recreational diving a limit of ppO2=1.4bar is normally used. ppO2 = 1.0bar is equal to breathing pure O2 at sealevel. ppO2 = 1.4bar is equal to breathing pure O2 at 4m depth. If you use compressed air it has ppO2=20,7% wich means that at 56m you get ppO2=1.4 which is why this is normally the absolute deepst you go on air. When using EnrichAirNitrox = EAN you have a higher percentage O2, which means that you Maximum Operating Depth MOD becomes less than 56m. And from there the diver becomes tech-diver with all kinds of exspensive helium-gasses.

Re:Not SCUBA

[Mostly Monkey]

Perhaps they could replace the weightbelt weights with batteries.

Re:Not SCUBA

[ConsumedByTV]

Put Another Dollar In.

Total bullshit :-(

Re:Not SCUBA

[wonkavader]

"Deeper, longer" (and uncut) seems like a controversial idea -- I don't mean just here, but rather, what about areas of the ocean with low concentrations, what other gasses get brought in, reserve capacity of the system, etc. What seems more likely and useful for recreational divers is "shallow, but longer." A 20 foot dive can now go on for hours. That'll be more fun for recreational divers who aren't interested in the down direction, so much as light reef diving.

Re:Not SCUBA

[Creedo]

The problem is, they dwarf the rest of the industry. The rest of the agencies follow their lead, as far as I can tell. I mean, they keep pushing the age limits on diving(it's down to 8 for their new program, I believe). I can't think of many 8 year olds that could physically handle a stressfull underwater emergency.

Some vintage divers I know have been kicking around the idea of starting a certification group focused on a mentoring style of teaching, like The Good Ol' Days(tm). I hope that they follow through.

Re:Not SCUBA

[petermgreen]

i'm sure the appollo missions used pure oxygen and they had the astronauts in it for quite long periods

maybe that was at least than atnospheric pressure though.

Re:Not SCUBA

[Anonymous Coward]

When going past a certain dept, I think it's mainly a O2 + Helium mix, hence divers sounding like Donard Duck.

Only the asian ones.

There is an asian Donard Duck?

Re:Not SCUBA

[FridayBob]

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.

This is why many technical divers like to use a closed-circuit electronic rebreather (CCR). A CCR is a so-called 'constant ppO2' device that allows you to breath gas with a constant ppO2 (partial pressure of oxygen) throughout an entire dive, independent of depth. CCRs are also very efficient with gas as well as silent (no bubbles!).

But that doesn't mean diving with a CCR gets you off the hook where decompression is concerned. The reason SCUBA diving will always contain an element of danger is that, no matter what equipment you use, the fact that the pressure differences are so great, coupled with the fact that, below 6 m depth, the use of a mixed breathing gas is unavoidable. By this I mean that, below 6 m, part of your breathing gas must consist of oxygen (max. 1.4 to 1.6 bar) plus another gas, such as nitrogen or helium (or a combination of those two) to make up for the rest. The problem is that you can't metabolize these other gases on the way up like you do with oxygen: these have to be outgassed slowly though the lungs (while breathing normally). If you don't take the time for this, these gasses will come out of solution in your bloodstream and soft tissues instead, which causes the bends.

Re:Not SCUBA

[Dr Tall]

I'm not sure if this answers the question decidedly, but I am actually also PADI certified. Here are the steps to getting each certification:

SSI: Take a 4-week class with a total of 32 combined hours in the classroom and in the pool. Take an examination. Complete 5 open-water dives with instructor. Receieve SSI Certification.

PADI: Go on a dive with PADI dive master. Mention to dive master that I am not PADI certified. Receive PADI Certification.

If you were referring to the post-"open water diver" certifications, however, that might be a different story. I don't know anything about PADI's advanced certifications, but I know that SSI has a heirarchy of them (and classes that go with them $$$) to rival Alpha Centauri.

Re:Not SCUBA

[zonker]

holy shit you guys. if this isn't a perfect example of, "don't believe everything you read on the net". remind me to never put my life on the line with a 'certified expert' diver...

anyway... that dude in the pic could be ron howard's lost twin. they are absolutely identical.

Re:Not SCUBA

[Anonymous Coward]

The author of the article is a medical doctor and a scuba diving specalist writing in his field of expertise.... and you're saying he's full of shit?

Yeah..

Re:Not SCUBA

[ConsumedByTV]

That's really interesting.

I think it's safter to learn from someone who knows, not just people who are "certified."

Re:Not SCUBA

[Creedo]

How do you think PADI and the other certification agencies started? Certified divers who were instructing got together and came up with teaching standards.

It is not that these people are looking to circumvent the standards now used. It is that they find those standards and practices to be, in many cases, insufficient. They don't wish to eliminate the certification agency. They want to make a new one that has more strict standards, with an emphasis on a mentoring style of teaching, versus the abbreviated classroom style favored today.

Besides, given that PADI would certify someone as an instructor with only 6 months and 60 dives worth of experience is, frankly, scary.

heh

[professorhojo]

i bet it's been tankless work. (sorry :)

Re:heh

[Anonymous Coward]

-4 bad pun.

Don't we have a mod for bad puns?

Re:heh

[Anonymous Coward]

yes, it's +1 Funny

Great technology!

[__aaclcg7560]

It's about time that technology is catching up with Star Wars. Now I can stay on the bottom of the swimming pool longer!

Re:Great technology!

[applef00]

Actually it was in Bond before it was in Star Wars.

Re:Great technology!

[Ucklak]

Star Wars came before Bond long ago in a galaxy far, far away...

Re:Great technology!

[Rei]

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 using it on diesel submarines. Sounds great, unless you consider that if they can get oxygen out of the water, they may well try and power the engines underwater as well instead of running on batteries. That would strip huge amounts of oxygen from the water; it's more than a bit concerning.

I'd feel a lot more comfortable with a method like this being "backup oxygen", instead of it being primary oxygen with a small backup oxygen tank. Of course, it's probably heavy eq...

Also... wouldn't this be noisy? A high rpm motor centrifuging gas out of water, right on your back in an environment where sound conducts very well?

Re:Great technology!

[applef00]

All right, that was funny. But way too easy. On this world, Bond came before Star Wars. If I'm remembering the order of the films correctly.

Re:Great technology!

[__aaclcg7560]

I wonder how long it would before my fan club showed up. And your point being what?

Re:Great technology!

[Zeinfeld]

The 'rebreather' was used in Thunderball which came out in 1965.

Star wars came out three weeks ago, so Bond was first by years.

After the film the US special forces called the special effects people to ask how long someone could last underwater using the rebreather. 'About three minutes', 'but our guys can do three minutes just holding their breath', 'that's what Sean Connery was doing, its just a piece of coloured plastic tube'.

Re:Great technology!

[Anonymous Coward]

And your point being what?

My point was, if you ever decided to put your fat fucking mass of human bacon grease under water, the water displacement would flood the world and not even Noah's ark could save are asses.

Re:Great technology!

[__aaclcg7560]

Funny, that didn't happen when I got into the pool last week. I think the neighbor's kids displace more water by doing belly flops every five minutes. As for the ability to flood the entire world, I think you're confusing me with God. Please... get off the floor and stop worshipping me. I'm just a large man. :P

Re:Great technology!

[shutdown -p now]

Yeah. And just think about all those mammals using up the valuable resources, stripping huge amounts of oxygen from the atmosphere... evil!

Re:Great technology!

[danharan]

Given that they are looking at military and recreational uses though, a loud motor just isn't going to have commercial potential.

As for oxygen being stripped out, it really shouldn't be a big deal. It's not just oxygen, but all dissolved gases. Humans will be just another animal getting its gas from the water, and they won't be staying very long.

For sensitive sites there may be different concerns than you would have with tanks; then again maybe people should be avoiding those places altogether no matter what the air source.

Re:Great technology!

[Suidae]

In the open ocean, they talk about using it on diesel submarines. Sounds great, unless you consider that if they can get oxygen out of the water, they may well try and power the engines underwater as well instead of running on batteries. That would strip huge amounts of oxygen from the water; it's more than a bit concerning.

Don't worry, its already taken care of. The fishing industry has netted out most of the critters that would've used the oxygen anyway.

Making good on a bet

[Anonymous Coward]

So, is it time for Jon S. von Tetzchner to make good on his part of the bargain?

Great!

[pomo monster]

Now you just need some batteries: "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!

[Anonymous Coward]

You need some extra weight to sink in salt water anyway. So instead of a weight belt you will have a battery belt :)

Re:Great!

[david.given]

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!

[climbon321]

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.

Re:Great!

[kouhoutek]

--- diving is one of the few activities where you can be under ten metres of water and still have a dry throat.

Um...diving i sone of the few activities where you can be under ten metres of water...period!

Re:Great!

[soupdevil]

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!

[HermanAB]

Just make the container the right size, so that the battery has neutral boyancy.

Re:Great!

[scottv67]

I'm having trouble thinking of ANY other activities where you can be under ten meters of water.

So I take it that you've never hitched a ride home from a party in Chappaquiddick with Edward Kennedy?

Re:Great!

[smithwis]

Drowning

Re:Great!

[Thaelon]

Exactly what other activities are there where you can be under ten meteres of water that aren't diving?

Re:Great!

[still cynical]

Drowning.

Re:Great!

[dfghjk]

Far, far lighter. Like an order of magnitude.

What they don't say is that when you flood that lithium battery it will most definitely explode and kill you. Lead acid batteries would be a far safer choice but the weight would be much greater (but less than a tank).

Re:Great!

[berryvanhalderen]

You're almost right, even the human body becomes negatively bouyant below a certain depth, because the pressure compresses the body. With a semi-dry suit this happens around about 10m, but it also happens without a suit.

And with a real steal tank you'll definitly sink (unless you are seriously fat). Steal tanks are in use in the Netherlands much, but most other countries use aluminium (which is still a lot more heavier than carbon, but never heard of plastic).

Carbon tanks need extra weights, you're right, and are too fragile for most uses. I recognize the part of dry mouth though, even salt water tastes nice in those circumstances.

Re:Great!

[deft]

Oh, and divers very rarely breathe oxygen. (Unless you're counting the weird mixtures you use for very deep diving.)

I routinely breath NITROX/oxgen enriched mixtures for regular recreational diving... there's no issue with it.

Re:Great!

[SECProto]

You're somewhat right. I teach swimming, and I know for a fact that I sink without weights, and with a full breath of air - I can take a huge breath, and sinky until my head is just slightly underwater. If i take a smaller breath, i sink no problem. I don't need any lead weights.

Re:Great!

[zippthorne]

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 a typical scuba tank involves bringing ever heavier tanks with more air. (or risky rebreathers.. they are at least as complex as this device appears to be from the article). This system appears to have some of the same advantages as a rebreather: namely that volume of gas available is not dependant on depth. This is a huge advantage for deep dives. It also seems to avoid some of the more worrying dangers of rebreather operation: there is no CO2 removing compound to react poisonously with water in the event of flooding, the O2 partial pressure is almost certainly above the minimum requirement for life (though must still be monitored). It introduces other dangers which must be evaluated: parts moving at high speed which could fail, does not have the favorable buoyancy characterists of a rebreather (each breath, buoyancy varies by the volume of O2 consumed rather than by the volume of an entire breath)

I would imagine that this would be about the same weight as a similarly capable rebreather assuming the 1kg/hour marginal weight cost. A typical laptop battery is a little under a kilogram. It would seem that the fuel-cell replacements for same would be a pretty good fit here (few moving parts, high energy density, relatively low power) Though it would add additional complexity. I'm not sure I'd want to have my primary breathing gas dependant on a battery that loses capacity as quickly as LiIon though.

Re:Great!

[DiveX]

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 approx 6 pounds). A steel tank is typically negatively buoyant, even when empty. Divers need to carry weight/ballast so they can remain at their decompression/safety stop depth, even with a near empty tank, and to compensate for the positive buoyancy of exposure protection (e.g. neoprene wetsuit).

I don't think "plastic air tanks" are available. What you are most likely considering is the carbon fiber tanks that firefighters use. They need something lightweight since they are always carrying them above water. They would not be useful for underwater use since the diver would have to carry a lot of weight to overcome the positive buoyancy aspects of the tank on top of the ballast for theit exposure suits and natural buoyancy characteristics.

Oxygen is used to accelerate decompression after deep or long exposure dives. Oxygen is not taken below a depth of 20 feet (1.6 atmospheres) due to the effects of exposure. It can be managed, but just takes experience, training, and very good depth control. On deep dives, I'll normally have a scooter, 2-3 other bottles beside my backgas tanks, and will be drifting 3-60 miles away from shore without anything onto which one can hold onto for support while maintaining the exact same depth for 20-30+ minutes.

Compressed air does indeed have moisture filtered in order to avoid oxidation in the tanks. Most shops use partial pressure blending techniques to mix the Nitrox blend. Normally AVO (Aviator's oxygen) is used (instead of medical oxygen) since it is easier to obtain [some places claim some BS about needing a prescription], and because it has been ultrafiltered for moisture so it would not freeze the plumbing in planes at altitude. /technical diver //SCUBA instructor

Re:Great!

[pmc]

Oh - I dunno - never driven a car in a tunnel under a river?

Re:Great!

[zippthorne]

You want it to be lighter for the walk to the dive site. Ironically, steel tanks though having worse strength-to-weight ratio than aluminum tanks and generally being less buoyant than the aluminum ones, are also often lighter for the same volume of air. This thing doesn't even need to be neutrally buoyant until its in the water and fills up, that space can be filled with air until then.

Re:Great!

[AsnFkr]

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


About the same provided the tanks are empty, actually.

Re:Great!

[Anonymous Coward]

Not easy to get to that depth by accident. If you just fall in and drown, you'll float at or very near the surface. Maybe if you're wearing cement shoes you could drown at 10 metres.

Re:Great!

[Anonymous Coward]

Freshwater or Salty?

Re:Great!

[The Master Control P]

As far as I understand, the actual energy density of batteries is or is nearly as high as it can get given the energy available from rearranging the electrons in them; The only way to get more power is to either engineer them to deliver electrons faster (but that only increases watts, not total joules available) or use a new chemistry, and we're running out of those too.

Re:Great!

[ch3]

Actually there is carbon tanks for scuba diving but I can't find any references in the USA.

My local diveshop sells some but they much more expensive than steel tanks. I wouldn't like them underwater but I sure would love my tank to be lighter when carrying it around before and after the dive :D

Re:Great!

[chr1sb]

That would be any of the activities performed in a submarine...

Re:Great!

[CFTM]

You most definately can get ten meters underwater surfing, although that's usually a real real bad thing and you probably just tried to surf a wave that was way too big :)

Re:Great!

[Anonymous Coward]

You are such an idiot. The only reason YOU need to wear weights is that YOU are a fat piece of crap. I decided to check in my dive log just to make sure, but with a steel tank, 4500 psi I'm carrying 0 lb extra ballast. Of course I don't need to wear neoprene either because where I dive it's so warm that we only wear trunks for decency and a t-shirt to keep the BC from rubbing. Mix in a 2 mil shortie or a 9 mil farmer john or a 9+7 'cos it's really freaking cold in the Great Lakes and I'm trying to overcome the bouyancy of the neoprene, not the blubber that's in your skull.

Re:Great!

[FridayBob]

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

Genrally speaking, lighter when you're above water, the same when you're underwater (because then the object is always to be neutrally buoyant). However, if the device is smaller in volume overall, then you'll be more streamlined and will be able to move more easily underwater.

Good News...

[Anonymous Coward]

It's a suppository.

Re:Good News...

[th1ckasabr1ck]

Professor: Oooh that reminds me: You've all taken your pressure pills, right?

Amy: Yes. STOP asking!

Re:Good News...

[Reorax]

You use that line instead of "I'll take lungs now, gills come in two weeks"? You should be ashamed. And you could have even thrown in "Z is just as good as X. In fact, it's 2 better."

Re:Good News...

[FuturePastNow]

This is uncomfortable and humiliating. Now, if they could put it in the form of a suppository...

Re:Good News...

[AndreySeven]

for those of you who don't know this quote, its from Futurama.

I was thinking more

[DrinkingIllini]

like those things they used in TPM. Just a little mouthpiece or something like that.

It still looks a lot like conventional scuba gear, but I'm guessing the tank is lighter, plus you don't have to worry about running out of oxygen.

Cool Invention

[Anonymous Coward]

Now you too can sound like darth vader under water!

One kilo what?

[hthite]

Calculations showed that a one kilo Lithium battery can provide a diver with about one hour of diving time.

One kilo what? One kilo watt? or One kilo weight? I thought they measured batteries in Ah.

Re:One kilo what?

[Nos.]

I think the sentence prety much tells you that they are discussing mass. Since they are discussing a given measurement of a battery will provide one hour of power. That almost guarantees mass, though I guess there is a possibility of volume. I think its a fair statement since the normal limitation of batteries is mass, so in this case I would read that as one kilogram.

Re:One kilo what?

[Anonymous Coward]

Just a guess, but I bet it's kilogram, which would be mass, smartass.

Re:One kilo what?

[HermanAB]

No, no, batteries are measured in libraries of congress per kilometer.

Re:One kilo what?

[MAdMaxOr]

...Gram. Kilogram

Re:One kilo what?

[Anonymous Coward]

In the real world, that is, outside the USA, kilo = kilogram, in common speech. It's not wrong, it's just efficient.

Re:One kilo what?

[DMUTPeregrine]

You mean libraries of congress per furlong.

Re:One kilo what?

[Anonymous Coward]

Is this the same Lithium that reacts violently with water and could even explode as described here http://www.rod.beavon.clara.net/lithal.htm

Oh yeah that's safe

[Rosco P. Coltrane]

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...

Re:Oh yeah that's safe

[Penguinshit]

Uh, the keel would be the least of your worries.. your real cause for concern would be the big food-processors to the stern.

qui-gon's dream...

[rocketman768]

Interesting. It comes out right when they show those fancy small versions in Star Wars.

Re:qui-gon's dream...

[Anonymous Coward]

Interesting. It comes out right when they show those fancy small versions in Star Wars.

Considering that the devices weren't featured in the most recent film, I'd say they need to work on their timing somewhat...

Re:qui-gon's dream...

[Anonymous Coward]

And decades after a similar device showed up in James Bond (I think it used O2, but then, does it anywhere in TPM say that the little thingy doesn't just have O2?)

Re:qui-gon's dream...

[Steev]

Yes they were. After Obi-Wan gets knocked into the water of that mining planet when the clone troopers turn on him, he swims to the surface and pockets one of those devices.

Just another..

[jlebrech]

gadget for James Bond.

Re:Just another..

[Anonymous Coward]

You're about 40 years too late.

Bond already used Qui-Gon's gadget once before.

Re:Just another..

[Anonymous Coward]

Actually, he had a The Phantom Menace thingy in one of the old movies (with Sean Connery).

Sounds good and all, but...

[Ingolfke]

will it use Intel chips?

Re:Sounds good and all, but...

[Anonymous Coward]

I think its hilarious

Re:Sounds good and all, but...

[Zardus]

Of course not! With global warming and all, the last thing we need is to boil the oceans with the chips' heat output!

Re:Sounds good and all, but...

[Luke-Jr]

Dunno... it gets pretty cold up north...

Crossing the Channel

[Anonymous Coward]

As nifty as this gadget seems, it does not affect the distance between England and France. I'm willing to bet it will take exactly the same amount of time for someone to swim the Channel as it did previously.

Re:Crossing the Channel

[Anonymous Coward]

as the artical said.. it could be used to swim a cross the Engish Channel underwater... not any faster.. but just underwater.

Re:Crossing the Channel

[scottv67]

I'm willing to bet it will take exactly the same amount of time for someone to swim the Channel as it did previously.

but if you were swimming the route underwater, wouldn't the distance between England and France be shorter due to the curvature of the Earth? If you were 20 feet closer to the center of the Earth (meaning you are swimming 20 feet below the surface of the water), wouldn't that be a shorter trip than swimming at the surface?

Backup oxygen?

[newnam]

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?

Re:Backup oxygen?

[Anonymous Coward]

did you look at the diagram? the one that showed the reserve air supply?

Re:Backup oxygen?

[MrFlannel]

Look at the picture; on the front of the guy there is a tank with the label "emergency air supply" for just such an occasion. Of course, one has to wonder if said oxygen tank will allow you to properly decompress in time. Of course, when faced with running out of air, the bends may be the least of your worries. Of course, with SCUBA you always have redundant systems, and having an air tank that's insufficient for it's purpose doesn't seem to fit the bill.

Re:Backup oxygen?

[gregmac]

Of course, one has to wonder if said oxygen tank will allow you to properly decompress in time. Of course, when faced with running out of air, the bends may be the least of your worries.

With recreational diving, also called no-decompression diving, the idea is that you can immediately return to the surface at any point. Usually, we take a 3-5minute decompression stop at 15', just as a precaution.

To get certified (with PADI anyways) one of the things you have to do is a controlled emergency ascent (which is basically your worst-case solution if you run out of air). You actually have enough air in your lungs that on a full breath you can quickly (at the speed of bubbles) swim to the surface and you will be able to slowly exhale the whole way, since the air expands as you go. Of course, if you do this from below 60' it would probably be a good idea to go to a decompression chamber to be sure. We had to do it from 30' I think, and it was by far the least fun thing in the checkout.

Re:Backup oxygen?

[HermanAB]

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.

Re:Backup oxygen?

[dfghjk]

You do NOT always have redundant systems with scuba. In no-deco diving none of the breathing system is redundant. Your bailout plan is a buddy or the surface. It might help if you were certified.

Re:Backup oxygen?

[akvalentine]

We had to do it from 30' I think, and it was by far the least fun thing in the checkout.

I just got my open water cert in February, with my dives done in Whitter, AK. With 36 degree water, the mask removal and flooding was the worst.

Yeah, I won't be doing any more diving in Alaska. I'll save it for vacations to someplace warm!

Re:Backup oxygen?

[StikyPad]

We had to do it from 30' I think, and it was by far the least fun thing in the checkout.

Heh.. we had to do it at 30', swimming 30ft level, which takes away the advantage of bouyancy helping you to the surface and the expansion of air in your lungs. Even so, my least favorite part was the stupid 200m swim, which we did in the ocean (helped for bouyancy at least) with a nice amount of chop since we were technically under typhoon condition 2.

Re:Backup oxygen?

[anthony_dipierro]

It is never a problem to get back to the surface.

I think his question was whether or not you could get back to the surface without dying shortly thereafter.

Re:Backup oxygen?

[JaredOfEuropa]

Does the device generate oxygen fast enough that if it does stop functioning, you have enough oxygen to get back to the surface?

A valid concern... the diagram in the article does show a diver carrying a 'pony bottle' on his chest; basically a very small pressure tank with a breathing apparatus on top, making it a completely self-contained and highly reliable emergency air source. I trust SCUBA enough not to take a pony bottle, but with a device such as this one I would definitely take one along.

TUBA?

[stagl]

Tankless Underwater Breathing Apparatus...

I think that TUBA is already taken. :)

Oxygen tanks

[lorcha]

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 certainly have never run out of air while diving.

Re:Oxygen tanks

[TheGavster]

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.

Re:Oxygen tanks

[prgrmr]

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.

Re:Oxygen tanks

[CharlieHedlin]

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).

Re:Oxygen tanks

[gregmac]

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.

Re:Oxygen tanks

[monkeydo]

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.

Re:Oxygen tanks

[krady]

Also it would definitely simplify your weight distribution. I prefer integrated weights (being overweight I am very bouyant and so need a lot) and , in conjunction with a tank, they can definitely cause a lot of BCD inertia.

Of course, I'm wondering how well all those neat holds you learn in PADI Rescue will work without a big tank stem/First Stage to grab.

Re:Oxygen tanks

[DiveX]

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 itself). This isn't deadly in itself, however being underwater with a regulator in your mouth can lead to drowning when you drop it while blacked out.

A certain cave diving team regularly decompresses on 100% oxygen at 30 fet, however they are in a dry area and can afford the risk, however they take breaks on a regular basis, by breathing a low FO2 gas, to reduce the amount of 'oxygen loading'.

Stop posting your guesswork when you have no idea of what you are saying. /technical diver //nitrox SCUBA instructor

Re:Oxygen tanks

[wooley-one]

Running out of air really isn't that big a deal if you are within reasonable limits. As long as you're above about the 60 foot mark, and don't require decompression, you should be able to come straight to the surface. You will usually have enough air in your lungs to last you that long. In addition, you will regain the ability to extract air from your tank as you ascend.

Re:Oxygen tanks

[huge]

Nitrox is used to address the problems caused by residual nitrogen. It allows longer bottom time in the same depth compared to compressed air, and it allows shorter surface time between repeated dives. For quick info take a look at http://www.techdiver.ws/nitrox_eng.shtml

I don't believe anyone is using pure oxygen as only breathing gas while diving because once o2 partial pressure gets high enough it, becomes poisonous. In tech diving, 100% o2 maybe used as decompression gas at ~6m and above. Tech/Rectec isn't my area of expertise so google will probably give more info than I ever can.

I certainly have never run out of air while diving.

More you dive, more certain you can be that it happens to you. It's not the best experience one can have during the holidays, but it'll teach you something ;)

Re:Oxygen tanks

[Jim McCoy]

I think others will hit the "does anyone dive on just O2" answers by pointing out the point where O2 gets toxic. So the answer to your question of whether or not anyone dives with _just_ a pure O2 tank will be "no". If I am doing a deep dive with a decco stop and want to offgas faster before leaving the water I will take a 100% O2 tank for the last stop, but more often than that will be having a 50% O2 tank that can be used for the last couple of stops. You will get the nitrogen out of your blood faster by reducing the partial pressure of N2 in your lungs, and you do this by replacing the N2 in what you are breathing with more O2 -- it sucks the N2 out of your tissue a lot faster.

Having said all that, the closest you will come to someone diving on pure O2 is a closed-circuit rebreather. These systems will have a tank of O2 that is bled into the gas loop you are breathing from to replace the O2 that your metabolism has converted to CO2 (which is pulled out via a lithium hydroxide cartridge usually.) There will usually be a second tank of gas to keep the breathing loop at the appropriate pressure for the current depth.

What this invention could do is replace the O2 tank in this sort of rebreather with something that would pull the O2 out of the water.

Re:Oxygen tanks

[Xtraneous]

Not necessarilly. There are several procedures that when out of air, one can use to reach the top safely.

Of the five (?) or so, my personal favorite is the CESA (pronounced like "see-saw"): the Controlled Emergency Swimming Ascent. Basically, you take one last deep breath, hold your mask and regulator on your face, say "Ahh...", and swim directly up. Because the air in your lungs decompreses as you rise, you are essentially able to breathe out (without feeling woozy) for about 1+ minute(s).

Re:Oxygen tanks

[CmdrGravy]

Heh heh . . . take one last deep breath

Hopefully not !

Re:Oxygen tanks

[Anonymous Coward]

I normally tend to surface when I have approx 50 bar left in my tank. I couldn't rely on a dive computer to know how much nitrogen is in my bloodstream.

What dive computer do you have? cos I'd love one that gives me that kind of information as a backup.

If there is a dive computer that does calculate the amount of nitrogen is in my bloodstream then it can only work on an average so I still couldn't trust it. As a responsible diver I would prefer to rely on proven technology (i.e. RDP) and stay within the guidelines than stray beyond them and have to rely on technology to tell me that something is very, very wrong.

Amazing that someone didn't think of this before

[nganju]

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.

Other implementations...

[foos_guy]

What about using the same technology for a submarine or an underwater research facility? Instead of using scrubbers to clean the oxygen, a larger device can be used to "make" more oxygen...

Re:Other implementations...

[joey.dale]

CO2 becomes toxic at about 4%. Thats why there are scrubbers.

-Joey

Oxygen tanks??

[Skiron]

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, but not for the common man if it do9es just extract pure oxygen from the water.

Re:Oxygen tanks??

[Anonymous Coward]

it doesn't extract pure oxygen from water it extracts the air in the water. "Studies have shown that in a depth of 200m below the sea there is still about 1.5% of dissolved air."

Read the report, will you?

Re:Oxygen tanks??

[Skiron]

Heh. So what is air then? So it extracts oxygen, nitrogen, carbon monoxide, cigarette smoke, farts, and that terrible smell I get when at the train station?

'Extracts air...'

Re:Oxygen tanks??

[Anonymous Coward]

Huh?

Compressed air is what people breathe down to 50 meters. "Professional divers" also used compressed gasses, but they might use a Nitrox mix that is different from ordinary compressed air, allows greater bottom time with less risk of embolism and narcosis but is generally limited to somwhat shallower diving. Saturation divers (typically deep divers who stay down a long time) breathe a mix of oxygen and helium, another intert gas that carries less risk than nitrogen. Rebreathers use scrubbers to counteract the buildup of carbon dioxide and recirculate "clean" air to the diver. They don't deliver pure oxygen--as you pointed out, pure oxygen is toxic to humans at depth.

Re:Oxygen tanks??

[ArieKremen]

What's the difference between "NORMAL" air, and "compressed air". If I want to squeeze any significant amount of air into a steel tank I have to compress atmospheric air, turning it into "compressed air". So, what's so special about the Royal Navy using it, or do civilians not have access to compressors?

What about Rebreathers?

[Anonymous Coward]

They've been around for a long time. No bubbles either. This is far from a first.

BS

[Anonymous Coward]

Um, yea, this looks realistic.

1) Not a credible news source.
2) Something this simple, assuming it could provide enough oxygen, would already have been invented.

Obviously, propaganda at best.

Old hat

[TheHawke]

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.

Re:Old hat

[delibes]

But with a living, breathing, working mammal, thats a whole different kettle of fish.

That is just the best mixed-metaphore that I've heard all day. Kudos, please mod the parent up!

And it's begging for a "this is a dead parrot" joke...

Re:Old hat

[Oligonicella]

You do realize, don't you, that birds are not only warm-blooded, but live, breath and work as well? Many birds (smaller ones included) are warmer-blooded than mammals.

Re:Old hat

[Anonymous Coward]

yeah so do I, after all, what chance is there of the Israeli guy actually working on this knowing as much as a /.er?

Comment removed

[account_deleted]

Comment removed based on user account deletion

Reminds me of Real Genius...

[veganjay]

"Want to help me test my re-breather?", Jordan

Similar idea, but I guess this is more like gills, while re-breathers "recycle" the air.

Full battery charge

[jbeaupre]

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.

Re:Full battery charge

[Anonymous Coward]

Now you'll need a reserve battery (for your reserve air)

Or a small airtank like they show in the article.

Re:Full battery charge

[djrogers]

Next time you dive you should remember what your instructors taught you - you should be back on the surface when you hit 500 psi, not 70 feet down looking at a 5-10 minute ascent... tsk tsk tsk.

Re:Full battery charge

[jbeaupre]

That was the idea. But the really scary thing is that it was my instructor's partner who supplied the equipment then took a group of us on a small cave dive. I noticed I was running low and returned sooner than anyone else in the group so as to reach the surface at 500 psi. I did not like leaving the group! I was at 700 leaving the cave at 90 ft. Not good! Had to swim a bit to get clear for ascent. Then ... no air.

I'm glad training kicked in and I didn't panic, but I'm lucky stupidity (mine and others) didn't kill me in the cave.

I wasn't able to read the article, so I'm glad folks pointed out there is a reserve tank.

Popular Machanics in the 60's...

[WindBourne]

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.

Who is going to use this?

[Locke2005]

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.

Re:Who is going to use this?

[metallic]

For the vast majority of recreational divers, an equipment failure is never really poses a safety hazard. For SCUBA divers, it is not a problem to ascend from 60 feet on one breath of air, exhaling all the way up to avoid a lung embolism. Combined with the fact that most people dive in pairs, equipment failure is really more of a inconvenience than a life threatening problem for most recreational divers.

The possibility of salt water leaking into the electronics is also basically a non-issue. With a decent underwater housing, electronics being destroyed by contact with salt water is almost unheard of.

Re:Who is going to use this?

[PudriK]

Yeah, bet they said the same thing about SCUBA. Everything has lots of failure modes, and that's why engineers either over-design, add safeties or provide back-ups. In this case, a small bottle of spare-air, like divers already routinely carry, would provide back-up for ascent. No "fool" is going to be "relying on this gear" soley until its been well-engineered. For crying out loud, it's not even a prototype yet! Give it a decade or so before being so pesimistic.

Re:Who is going to use this?

[dukeisgod]

The diagram in TFA shows a small air tank for backup.

Re:Who is going to use this?

[OzRoy]

A single failure can already kill a diver. A crack in your regulator hose can empty your tank in a few seconds. A stretched bourden tube in your pressure guage can make you think you still have 50atm of air left when really your tank is empty. It doesn't matter what system you use, it will go wrong.

Go meet some divers and you can be guaranteed of meeting people who have had things go wrong with their equipment, and had to make an emergency ascent.

Re:Who is going to use this?

[Anonymous Coward]

This is true. SCUBA, in its present form, uses pretty simple mechanics to operate -- an air tank with a set of valves. It's pretty hard to screw up, unless you do something stupid (and of course, you should always check your equipment before you dive.)

The biggest problem I see with this is that it's an electronic/electrical system -- it's 10X more complicated, and therefore much more prone to (potentially) life-threatening problems. You'd almost certainly have to have an emergency air supply, and it would have to be sufficient for you to do at least a 5-minute safety stop to avoid the bends.

Re:Who is going to use this?

[z0idberg]

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.
I would much prefer to use it in the reverse. Have this as the main and a small air tank as the reserve (as it shows in the diagram). Thousands of people a day use things where a single failure can kill them (e.g. current SCUBA tanks, parachutes, Bungy jumping, abseiling).

how long will it take for someone to use this to..

[HotNeedleOfInquiry]

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.

Shaman can already do this with shiny fish scales

[Anonymous Coward]

Oh dear I've been playing too much WoW!

http://thottbot.org/?i=2442

I hope the corporate IP lawyers take note

[symbolic]

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.

Re:I hope the corporate IP lawyers take note

[Ill_Omen]

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.

Re:I hope the corporate IP lawyers take note

[back_pages]

What's hilarious is that this is moderated insightful. It is foremost indicative of the general Slashdot understanding of the patent system.

Novel and non-obvious is a pretty succinct way of describing a bad idea. People rarely publish their stupid ideas; it reflects badly on the inventor. In fact, the best rule-of-thumb for patentability is how stupid an idea is. The worse the idea, the less likely it is that a patent examiner can prove it has been done before.

As some of the more astute posters have replied, there is ample motivation to produce an invention like this from, if nothing else, piles of science fiction novels. While that doesn't prove it can be done, there can be no argument that it would be obvious to try to make the invention, at least taken as a whole.

Since it is obviously a great idea for an invention (even a typical Slashdot reader can recognize that) the patent application must be given the highest scrutiny possible. If it were a stupid idea, the resulting patent would be merely ornamental, and subsequently easier to secure.

In summary, when I compare what I read on Slashdot about the patent system to facts, I find it quite humorous. There is no comparison. I respectfully urge interested Slashdot readers to skim the Manual of Patent Examining Procedure, particularly chapter 2100 (more specifically, 2141, 2143, 2144, 2164 to get started).

I fully expect to be flamed for this post, as is customary when someone with actual experience or expertise posts about the patent system. I clearly don't care about that or I would have quit long posting about patents long abo. My point is this: Nobody with any knowledge of the patent system will ever listen to anything coming from Slashdot until it exhibits a basic understanding of the system it criticizes. If you want to be taken seriously, you'll have to educate yourselves. More to the point at hand, there is absolutely no legal requirement that a patent should be denied to a simple or stupid invention. If you think that "obviousness" refutes that, please read MPEP 2143 and 2144 to understand why that is incorrect.

Re:I hope the corporate IP lawyers take note

[Anonymous Coward]

there is absolutely no legal requirement that a patent should be denied to a simple or stupid invention

If the guy had filled a patent on the "idea" of "breathing underwater like a fish" aka "B.U.L.A.F", then yeah, it would be considered a stupid patent and most likely denied as overbroad. As it stands, it a novel and clever way to to "B.U.L.A.F". So, let me emphasize for your benefit.. His patent doesn't prevent anyone else from coming up with a different "way" of "B.U.L.A.F".

Hence, it's a cool patent.

Unfortunately the patent examiners are a bit stupid when it comes to software patents and hence overbroad software patents are being filed and approved. Filed by companies with enough cash that only people that have 'multi-national conglomerate' tacked onto their bussiness cards could ever hope to afford a legal challenge.

Nobody with any knowledge of the patent system will ever listen to anything coming from Slashdot until it exhibits a basic understanding of the system it criticizes.

Till you realize that overbroad software patents are what Slashdotters are upset about the most, you should listen to your own advice.

Re:I hope the corporate IP lawyers take note

[Ztras]

It is not that novel... Fish do it all the time.

Re:I hope the corporate IP lawyers take note

[Junior J. Junior III]

His apparatus makes use of the air that is dissolved in water like the gills of a fish.

I call prior art.

Oh shit, the fish are suing!

No, it's OK; humans have prior art on the lawsuit. The fish have nothing!

phew.

Re:I hope the corporate IP lawyers take note

[arose]

If you think that "obviousness" refutes that, please read MPEP 2143 and 2144 to understand why that is incorrect.

The fact that patent offices lack common sense is well known, we don't need to read any manuals for that.

Re:I hope the corporate IP lawyers take note

[anthony_dipierro]

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.

Why? Do you think no one would have come up with the idea if it weren't for the fact that they could get a patent?

I don't think anything deserves a patent. If there's a problem that's really hard to solve, the people who want the solution can get together and offer a reward to whoever solves it.

Re:I hope the corporate IP lawyers take note

[Threni]

> This is the kind of work that deserves patent protection

Prior art - it was in the film The Abyss (a piss-poor Alien rip-off).

Re:I hope the corporate IP lawyers take note

[Sheepdot]

What about the guy that buys one, reverse engineers it, and releases the plans as open source? According to your model, IP law would still protect the inventor, and damn the copyright infringer, regardless of if they have the means to produce the product.

Re:I hope the corporate IP lawyers take note

[dascandy]

I still consider the australian patent of the wheel the least innovative one. Granted in the 21st century no less.

Re:I hope the corporate IP lawyers take note

[listen]

Till you realize that overbroad software patents are what Slashdotters are upset about the most, you should listen to your own advice.

Then you take it one step further, and realise that the subject matter of any software patent that was not overbroad would already be well protected by copyright, and you have the complete argument for why software patents should not be allowed.

Re:I hope the corporate IP lawyers take note

[Anonymous Coward]

Well, it's good that we have you here to decide what is and isn't worthy of patent protection. You should've presented your genius to the US government a lot sooner.

Re:I hope the corporate IP lawyers take note

[back_pages]

Unfortunately the patent examiners are a bit stupid when it comes to software patents and hence overbroad software patents are being filed and approved.

What do you know about patents? From what you've already demonstrated, the answer is "next to nothing".

Please cite ANY legal basis for rejecting an "overbroad software patent". There is no such legal basis. That you believe such a concept might exists is evidence that you don't know much of anything about how the US patent system works.

That was my original point. Your response to my point provided evidence substantiating my point. Respond however you like, but I consider my point thoroughly proven and the discussion complete.

No osmotic membrane at least

[snarkasaurus]

This is a novel approach. Kewl! I was afraid (before rtfa at least) that it would be another rehash of the old semi-permiable membrane schtick that's been around since Time Tunnel at least.

Keen if it works, O2 bottles are a large pain to fill and transport. Just ask a welder. ~:D

These are called rebreathers

[heli_flyer]

These systems are not new. They've been around for a long time. They're called rebreathers. Here's a link to a whole page full of links to rebreather manufacturers and homemade rebreathers: http://www.metacut.com/rebreathers/reb_pages.htm

Re:These are called rebreathers

[Anonymous Coward]

No, that's not what a rebreather is you silly bonehead. If you're going to be a pedantic ass, do try to not be wrong.

Re:These are called rebreathers

[bmalia]

What is a rebreather ... ? A rebreather is a self-contained breathing apparatus for use underwater which reuses at least part of each breath. This should be contrasted with "Scuba" (open circuit) where the entire breath is expelled into the surrounding water when the diver exhales. Rebreathers are able to reuse the oxygen left unused in each exhaled breath while they simultaneously remove C02 with a chemical which "traps" the C02. The net result is greatly extended dive times with relatively small tanks. An added benefit is a relatively quiet dive as there are little or no bubbles produced.

Not the same thing. These still use air from a tank, not from the water. But thanks for playing.

Funny stuff

[lilrowdy18]

Fry: "I cant smallow this thing."

Professor: "Good news. Its a suppository"

Re:Amazing that someone didn't think of this befor

[theGreater]

And how, pray tell, does one go about decreasing pressure with a centrifuge?

-theGreater.

Re:Take your last breath and not die!

[halivar]

You won't just be able to breath underwater--you'll take pleasure trips on the surface of the sun.

Sounds fun. Send me a postcard.

La Cosa Nostra

[jlowery]

Now "swimming with the fishes" doesn't seem so bad.

Re:La Cosa Nostra

[Heisenbug]

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.

Re:La Cosa Nostra

[TerranFury]

La Cosa Nostra sells pizzas. Guaranteed on time.

A step in the right direction

[Anonymous Coward]

Now if I could just breathe through my ears, I'd be a lot more popular with women...

Re:A step in the right direction

[ultramk]

That wouldn't work... in my experience, the ears are being covered by the thighs at that point--and clamped down hard if you know what you're doing.

Which is a problem 'cause you can't hear the front door open...

Ah, to be 18 again.

This underwater breathing thing would have come in handy at that point: I could have hid in the pond....

m-

It's too bad

[Anonymous Coward]

Well it's too bad that our friends can't be with us today
Well it's too bad
The machine that we built
Would never save us that's what they say
That's why they ain't comin' with us today
And they also said it's impossible
For a man to live and breathe underwater
Forever was a main complaint
Yeah and they also threw this in my face they said
Anyway you know good and well
It would be beyond the will of god
And the grace of the king
Grace of the king
Yeah

English channel? Hell - let me breathe LA air.

[UncleSocks]

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

Why stop there? Perhaps with this device, I could purify the air in LA well enough to walk across town.

Re:Amazing that someone didn't think of this befor

[merreborn]

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.

Batteries have been around for decades, yes, but it's likely that batteries with acceptable power densities have not.

Battery technology has continued to develop over the last few decades, for cell phones and laptops

Great way to die!

[Anonymous Coward]

Sigh...

Breathe a gas mixture with a PPO (Partial Pressure of Oxygen) of more than 1.6 bar and you'll begin convulsing. Technically, your death will be a drowning as you lose your regulator and asperate water.

1.6 bar = ~52 feet

Bah .. StarWars

[Anonymous Coward]

You obviously haven't see Graduate ..

Biology class lied!

[g0bshiTe]

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.

Re:Biology class lied!

[Vellmont]

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 a day, then came up just expecting everything to be fine?

Re:Biology class lied!

[Deliveranc3]

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.

Re:Biology class lied!

[kalayq]

If I remember correctly, sea water has nitrogen disolved in it too. Although along with those gases, there are a few others in large quantities like CO2 and Methane. How does this device keep out other gases?

Re:Biology class lied!

[Anonymous Coward]

actually I think your English class lied to you about what the word "like" means.

Re:Biology class lied!

[CmdrGravy]

The parts of the great barrier reef I have dived on went down to 30M+ in places which is certainly not where you want to be if you don't know exactly what you are doing.

Is it just me?

[Anonymous Coward]

Or is Alon Bodner actually Ron Howard?

Re:how long will it take for someone to use this t

[Skiron]

Already been done with SCUBA.

Variable ratios to match breathing?

[Delilah Jones]

This sounds really interesting.

Though, if you have ever been scuba-diving, you will recall that your breathing is not constant throughout the venture.

In fact, there are times when you are breathing just normal, and there are times when you are really huffing and puffing.

How would this "oxygen-extraction bag" be able to pull out the particles of air out of the water at a VARIABLE rate, to match the variance in your breathing volume (not to mention the variance across individuals)?

Would the contraption be able to do this quickly?

I would hate to have to tell myself to stop breathing so heavy, because my air-extraction bag is deflating quicker than it's filling!

On the other hand, what if it is inflating too fast for you to breathe it in?

I suppose these are minor engineering considerations, but I didn't find mention of them in the article.

Re:Variable ratios to match breathing?

[CmdrGravy]

Maybe it could use some kind of buffer ?

gungan

[Qnaal]

oh shiznit, jarjar flashback! *beats head with shovel*

Not good enough!

[CaptainCarrot]

I'm still waiting for oxy-gum like Marine Boy used.

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

Re:Not good enough!

[Anthony]

Thanks for the Marneboy link. I watched that religiously many moons ago. Always waiting for the hair to move in the right direction ;-). Never knew his suit was red!

Re:Not good enough!

[CaptainCarrot]

I guess this makes us anime fans of much longer standing than any of these kids around here!

I had a similar experience wrt Kimba the White Lion. (I mean about the suit, not the hair.) I always thought it was a black and white cartoon until I got the DVD set a little while ago. Surprise! It was my TV that was b&w, not the show. Silly me.

Re:Amazing that someone didn't think of this befor

[Anonymous Coward]

Ask Bernoulli..

Electrolysis??

[seabre]

"Engineers have tried to overcome these limitations for many years now. Nuclear submarines and the international space station use systems that generate Oxygen from water by performing 'Electrolysis', which is chemical separation of Oxygen from Hydrogen." ~From http://www.isracast.com/tech_news/310505_tech.htm

The last time I checked..electrolysis was just forcing a current through a cell to cause a nonspontaneous chemical reaction.. They went a little too far with trying to simplify that..or they just didn't know what they were talking about...

Re:Electrolysis??

[Anonymous Coward]

nonspontaneous?

Re:Electrolysis??

[geekyMD]

How many people would be fully aware of all the implications of adding 'nonspontaneous'? And how many who Do know the difference between a spontaneous and nonspontaneous reaction wouldn't also assume the nonspontaniety?

Would you feel any more informed if they had mentioned the dangers of 'spontaneous' explosive dihydronmonoxide recombination inherent to the process?

(Sorry! Somebody had to make the joke!) =)

Re:Electrolysis??

[tepples]

If you can't get a definition of a compound word in an online dictionary through its search tool, then over 90 percent of the time, the compound is the sum of its parts in meaning. In that case, look up the components separately: non- spontaneous

Re:Electrolysis??

[seabre]

I bolded it because it was an important part of the definition, to help show emphasis. I had no intention of using that to make what was stated in the article clearer.. :-)

Sort of like.

"Hey, that guy has a very big ass!"

I did too many electrolysis problems in chemistry for it just to be a "seperation of Hydrogen and Oxygen".

If that statement were actually true, it would've made life easier for me :-\.

Re:Amazing that someone didn't think of this befor

[Anonymous Coward]

I assume that if the outside has an increase in pressure, the center has a decrease.

Ah, the questions...

[BinaryLobster]

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.

Re:Ah, the questions...

[Anonymous Coward]

It might even be good idea to bring a pony tank, cause there are some dead areas that can't support aquatic life. For example near New Orleans in the Gulf, just read there are a few during the year in Chesapeke Bay and some other places around the world.

If there is no way to support aquatic life and you run it to one of those, you just pop up like a dead fish.

So at least my tanks will still be useful.But this is still a cool idea, just have to know the area your in and make sure like all dives, you take some precautions.

Re:Ah, the questions...

[nametaken]

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 other hand air time is pretty tightly related to size of your gear (larger tanks, two tanks, etc). But like someone else says, you still have to worry about nitrogen buildup, etc. Does it provide the other gasses? I don't wanna breathe plain oxygen, that's for sure.

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.

Hoot! Good question.

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.

This thing is going to end up being just as big and cumbersome as a regular tank rig. Really, I think everyones better off with a rebreather if they wanna go higher tech. You're going to have to condition what you leach from the water anyways.

And what about this... it still has to make air for your buoyancy control vest. I just don't see this being as simple as the drawing. :)

Re:Ah, the questions...

[Anonymous Coward]

So use two centrifuges spinning in opposite directions.

Re:Ah, the questions...

[Java Ape]

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.

Re:Ah, the questions...

[Derek Pomery]

This may seem silly, but if you're going to strap a battery on it anyway, why not use the battery to control buoyancy too?
Heck. Subs do it.
Could allow for automated buoyancy control.
Then you can get back to focusing on battery life or alternate power sources.

Re:Ah, the questions...

[AndreySeven]

RTFA it answers many of these questions

Re:Ah, the questions...

[BinaryLobster]

BMSMA (Bite my shiny metal ass).

I read the article.

Now maybe I missed the graphic of the emergancy air supply on the "purty" picture. But the FA didn't address the rest of my questions.

--------

I'd put a sig in, but it'd get trolled too.

Re:Ah, the questions...

[Moofie]

Uh, you mean the one that's labeled "Emergency Air Supply" on this image?

Re:Ah, the questions...

[BinaryLobster]

Yes. That is exactly the item I missed. :)

Re:Ah, the questions...

[Anonymous Coward]

What happens when you don't read the fucking article?

A: You look like a dickhead.

Re:Ah, the questions...

[jemfinch]

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

Re:Ah, the questions...

[Frodo Crockett]

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....

Re:Ah, the questions...

[Anonymous Coward]

Oooh, an engineering question!

Potential solution: have two centrifuges spinning opposite directions. I believe their moments of inertia will cancel out.

Of course if one fails, you'll get the amazing spinning emergency ascent.

Re:Ah, the questions...

[CmdrGravy]

And some battery powered device is easier than using your lungs ?

Re:Ah, the questions...

[Derek Pomery]

Well, easier to do a little pumping than make the device extract air from water *for* those lungs.
And an automated or semi-automated system could be easier for beginners.

Re:Ah, the questions...

[Anonymous Coward]

Ah, wonder what the trade off is between swimming with a heavy tank and swimming with a spinning mass are like.

With the spinning mass you will be very stable along one axis or the other. You may develope a slowly increasing wobble.

Too good to be true

[Anonymous Coward]

Someone needs to set all this misinformation straight.....

First, regarding the aforementioned tankless device...it simply isn't practical. I'm not going to post all the calculations, but the sheer volume of water required to enough O2 to reach even normoxic (PO2 of .16-.21) levels is astounding.

Second, we can't safely breathe pure O2 below 20fsw (ft of sea water)...it becomes toxic at PO2s > 1.6.

Third, a diver would need to bring an inert gas, such as N2 or He to mix with the O2 extracted from the sea to create enough *volume* of gas to breathe and to avoid oxygen toxicity below 20 ft.

Typically, recreational divers would be breathing compressed air or an oxygen enriched gas mixture to 100-130 fsw. Below that and the N2 becomes debilitatingly narcotic, so Helium is added to the mixture to lower the equivalent narcotic depth (END) to 100 fsw. If you ever read a report that says something about how the diver was out of oxygen, disregard almost everything that is said, as the writer clearly does not know a thing about diving....100% OXYGEN IS TOXIC BELOW 20FSW.

That being said, non-commercial/military divers breathe pure O2 only on decompression stops and ONLY ABOVE 20FSW....Decompression diving has become fairly common in the technical diving community with dives being done down close to 400 fsw fairly regularly.

How did I know ...

[DrugCheese]

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 ... ;)

useless

[Anonymous Coward]

this is a pretty useless invention,

You can carry enough compressed are with you to get yourself killed by DCS caused by being under too long.

The other way around, putting the air that is being breath OUT into the water would be very usefull for militairy use.

Ron Howard?

[brucehappy]

There's a water/oxygen transfer system, dumbass!

Patents

[kelzer]

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.

Re:Patents

[Xeger]

+1 Smartass, baby.

If you RTFA...

[Radical Moderate]

you'd have seen that the device includes an emergency air supply for those situations.

Re:Amazing that someone didn't think of this befor

[Garion Maki]

simple, just run it in reverse.

Great!

[The_Minkis]

Now I can finally swim to Ota Gunga!

Jar-Jar beware, you're in for a scare...

The Abyss

[slipper-e]

Is anybody else reminded of http://www.imdb.com/title/tt0096754/ Abyss? In the movie they added more oxygen to a water supply inside the helmet and you had to actaully breath the water inside your suit!

Re:The Abyss

[Elminst]

It's called liquid breathing...
And although is nothing like what is described in the article, it is pretty cool technology.
Research started on animals (mice) in the 1960's, and has progressed to the point where it's being used to assist premature babies with respiratory problems.
http://www.answers.com/topic/fluid-breathing

Re:The Abyss

[joto]

Is anybody else reminded of http://www.imdb.com/title/tt0096754/ Abyss? In the movie they added more oxygen to a water supply inside the helmet and you had to actaully breath the water inside your suit!

Whatever they used in the Abyss, it was most likely not water, as the sequence with the mouse breathing was not CGI. And water in your lungs is bad!

But, there do exist some breathing fluids, that among other things are being used on prematurely born babies, before their lungs are fully developed. AFAIK, using them for diving is still science fiction. You can read more about it here

Re:The Abyss

[Solder Fumes]

Using them for diving is NOT still science fiction. I knew an ex-military diver years ago who was involved in deep-sea experiments with liquid breathing. I'm not sure if he was supposed to talk about it at the time. He said it was definitely weird. The main thing was how cold it felt.

Re:The Abyss

[metachor]

I'm sorry our run-in with those aquatic aliens made you urinate in your suit, but you are just going to have to suck it up.

Re:The Abyss

[Anonymous Coward]

Cold temps prevent the CO2 from building up.

What about toxic gases?

[Dcnjoe60]

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!).

kilo-weight?

[alexborges]

That would be gram(base weight/mass unit of the metric system)....If not, it could well be a kilo-pound.

Sorry... the geek in me sheesh...

yeah thats great

[Anonymous Coward]

now instead of tanks I can dive with batteries on my back. nice.

assholes.

Disagree, think it could find a hold in rec diving

[SuperKendall]

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!

Fluid breathing

[Anonymous Coward]

Forget about all that. Fluid breathing is way cooler.

...because it's there...

[moviepig.com]

...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 . . .

Re: ...because it's there...

[t_allardyce]

underwater

Re:Amazing that someone didn't think of this befor

[MyHair]

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.

Well, sometimes if there is a good enough alternative nobody bothers to try other things. Corrective eye surgery is relatively new even though the tech has been around for ages. Glasses and contact lenses had everyone's attention, then some kid gets his cornea cut up from a baseball hitting his glasses, and after healing he can see better. 20 years later (I think) we have production lines of computer-controlled corrective laser surgery. I had the by-hand RK about 10 years ago...certainly that would've been doable decades ago if somebody had thought of it.

A few problems...

[waterford0069]

1) MOST recrational divers are using open circuit AIR tanks (~20% O2, ~70% N2, and ~10 Other), not pure oxygen. Even at that, pure oxygen becomes extramly toxic at certain presures.

2) What happens if the diver goes through a thermocline (which often coincieds with the oxycline)? He/She dies from lack of O2.

3) Basically, the only way to use this technology is in part of a rebreather system. While these do offer MUCH longer bottom times, they are just as bulky as a single air tank, and require far more taining than most recreational divers are capable of.

And for the tech-divers out there... I'd love to hear the tirade that G.I. the 3rd will have when he hears about this idea :-)

Re:Take your last breath and not die!

[sconeu]

You won't be able to see anything in the postcard. He's going at night, so he won't burn up!

Cooler Technology Out There

[Evil W1zard]

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, which then can be funneled into the swimmer's windpipe through a scuba mouthpiece. The Waseda team has been working on the gill since the mid-1990s and only recently created a version compact enough for field tests. The trick now is to figure out how to get a breathable amount of oxygen out of the hemoglobin solution. Once that's ironed out, it shouldn't be too long before humans and fish swim side by side for hours on end - which should finally prod science into solving the age-old riddle of wrinkled fingertips.

Re:Cooler Technology Out There

[Anonymous Coward]

Oh dear. The irony of having to "iron out" bugs in a hemoglobin-to-oxygen transfer system.

Uhhh... No

[notrehtad]

Other posts on pure O2 toxicity are on the mark, for sure, as are the posts on maintaining sufficient pressure in the system so as to keep your lungs from becoming the size of a large coffee cup at depth. What about stuff like rotational inertia of the thing keeping you from moving where you want, and the NOISE that this thing would make?

Old news :)

[cryogenix]

Star Wars has a much smaller version of this. We saw it again in Episode III when Obiwan get shot off his mount and falls into the lake :)

From TFA

[lorcha]

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.

You want to know what's awkward? Whatever happens when this device fails. Call me old-fashioned, but I would rather have a simple tank of air strapped to my back than the device in the article, which would have many points of failure. Being 100' under water with no source of air leaves you mighty frickin' vulnerable.

Yeah, I know. SCUBA tanks fail (normally a problem with seals). But they fail early to the tune of, "Dude, there are a fuckload of bubbles coming outta yer tank. Maybe you shouldn't frickin' dive with it." Ahhh. Simplicity. Simplicity is good.

Re:From TFA

[arose]

Call me old-fashioned, but I would rather have a simple tank of air strapped to my back than the device in the article

The tank may be simple, but you don't get air from the tank directly...

I am also a long time diver...

[MrPower]

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".

Re:I am also a long time diver...

[Anonymous Coward]

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!

No Fucking Shit. Go re-read the grandparent "one atmosphere extra pressure" = "1 + 1 = 2 atmospheres of pressure"

Re:I am also a long time diver...

[Anonymous Coward]

"Third, at 10m (~33 ft) you are at 2ATM pressure, not 1ATM!"

I believe that is why he said "1 atmosphere extra pressure".

Just nit picking...

Re:I am also a long time diver...

[Java Ape]

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.

Re:I am also a long time diver...

[Anonymous Coward]

The 1.5% of dissolved air was at 200m. At the sort of depths that air-breathing would be viable, the amount of air in there will be considerably higher, not that I have any idea how much higher. Also, who has a lung capacity of 3l, let alone a shallow breath of 3l. You'd be huge.

If we guess double the air and 1/3 the volume then that's a lot less seawater necessary to process, but still quite a lot, I suppose

Re:I am also a long time diver...

[carbon3C]

Hmmm... Halibut are large fish that can weight over 500 lbs. They exist in depths up to 500 ft. I've gone deep see fishing before at depths at 300 ft, but afterwards my friend bought a 400ft anchor and caught a 200lb. Because of their size, I imagine the large ones would require as much oxygen as a human. How many liters per minute do you think they need at depths of 300-500 ft? Not even close to 9000liters that you estimate for shorter depths. You need to research the science behind your claims before stating them so recklessly.

Re:I am also a long time diver...

[DiveX]

Oxygen is just as narcotic as nitrogen. "Nitrogen narcosis" is simply a misnomer. The only way to reduce narcosis is to introduce a lighter gases, namely helium (neon and hydrogen have been used, but they are quite expensive and have handling issues).

Argon (Ar): narcotic value = 2.33, helium (He) has a value 0.23. Both nitrogen (N2) and oxygen (O2) have the value 1.00. /tech diver //nitrox SCUBA instructor

Re:I am also a long time diver...

[StikyPad]

To be fair, the OP said "One extra ATM of pressure."

Re:I am also a long time diver...

[arose]

Also, who has a lung capacity of 3l [..]

A child? I have 5l.

Re:I am also a long time diver...

[Anonymous Coward]

Actually, (though rifting somewhat off-topic) a fish requires considerably less O2 than a human does simply because it's cold blooded. There's no "burn fuel just to keep warm" going on, and thus no need to have O2 with which to burn.

Additionally, fish have gills and "breathe" the water directly. They don't have to go to the extra step of extracting the gas and then breathing that.

The point he was making about requiring 9000 litres a minute of water was because of that final step - the need to extract gas from the liquid so the human can use it.

If there was some kind of rebreather involved (more like an artifical lung to handle the -only- the gas exchange) the volumes would be a lot lower, I agree.

Re:I am also a long time diver...

[mugnyte]

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 attitude of the chamber distorts the shape of the vortex and changes the rate gas can be extracted.

- After spinning, the gas must be collected without including the water. This would then be pumped into a chamber for storage.

- Defeat the consumption of gas in the storage chamber. At depth, less gas is dissolved per unit of fluid, and this make the aparatus worker harder to keep up. Also, your "dried" water source must be flushed.

- Key to this would be a constant-fed system that kept spinning while accepting fluid and delivering gas. Side issues are the buildup of sediment (while gas is being separated, so are things heavier than water), and the seawater encapsulation issues .

- You can enter "dead zones" in open water, where the type or amount of dissolved gas is not able to support life. This would be a big danger. One's storage mechanism would need to cover for just such an emergency. Enough to surface, with decomp time if warranted.

Personally, I think they should research more into completely bypassing lungs in the system. Folks could elect for bypass surgery that installed a machine in their chests, and blood would undergo the CO2/O2 exchange in the internal machine. The machine would expose plugs to the skin, and rechargeable devices could feed the required gasses. The ingredients could be varied based on heart rate. Stopping the breathing reflex may not be possible, so a small mouth-based device might be necessary (just an unprocessed recirculation system). The volumes of gas we're talking about in this instance are much less than lung capacity. Also, compromised lung function (through smoking/pollution/defect) would not apply.

The physiological effects of the human body underpressre are numerous. Different topic entirely

Re:I am also a long time diver...

[budgenator]

You have to learn to think in partial pressures,
Air is 20% O2, 80% 2 so;
14.7 psi @ 20% O2 = 2.94 psi O2, 11.76 psi N2; surface,
29.4 psi @ 20% O2 = 5.88 psi O2, 23.5 psi N2, 33ft below surface,
44.1 psi @ 20% O2 = 8.82 psi O2 35.28 psi N2, 66 ft below surface (this concentration causes blindness in newborn infants),
73.5 psi @ 20% O2 = 14.7 psi O2, 58.8 psi N2, 165 ft below surface ( the O2 is toxic here),
now if you change things a bit go to 165 ft and breath 68.5 psi of He2 and and a nice comfortable 5 psi O2, your joining to get as much oxygen as you would a 33 Ft and the smaller lighter easier to difuse helium molecules will not make your blood fuss up like a warm shaken bottle of soda pop. I think our Apollo spacecraft run at 100% O2 and vented down to 5 psi in orbit, which is why a fire on the launch pad was so fierce, they were at 14.7 psi O2 there.

Re:I am also a long time diver...

[horn_in_gb]

Vital capacity (aka the part of your total lung capacity that you regularly use) varies greatly between individuals, 5L is quite a bit even for an adult male. I'd say the average runs from 2-4L for a healthy, adult male, and a bit less for a healthy adult female. Lowell Greer (a professional horn player) once told me he had an 8L capacity when he was at his max (he mostly teaches and makes instruments now). The late Arnold Jacobs, one of the world's greatest tubists, had only one lung but it had a 5L capacity! That's quite extreme though. See http://en.wikipedia.org/wiki/Vital_capacity for more information.

Re:I am also a long time diver...

[Anonymous Coward]

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!

I find those calculations seriously questionable. First, you haven't explained where you got this mysterious "5 / 0.015 == 200 liters" formula from. First of all, 5 / 0.015 == 333.3, not 200. But let's assume you meant that say "3 / 0.015 == 200 liters". Then I would have to conclude you meant to divide the size of a "shallow breath" (3 liters) by the percentage of air in the water, since the article says "there is still about 1.5% of dissolved air" even at 200m down.

However, I don't think you can do the computation this way. It can't be as simple as just dividing. When a gas is dissolved in water, it no longer makes sense to measure its volume as if it were still a gas. The O2 or N2 molecules are dissolved, so they are not behaving as a gas: they're just floating around between the molecules of H20, which are acting is a liquid.

The article is not clear, but the only reasonable way I can think of to use a ratio to measure how much dissolved air there is in seawater is to do it by mass. So, 1 L of seawater would weigh approximately 1 kg (slightly more, actually, but I'll be conservative and call it just 1 kg). If 1.5% of that mass is air, then you've got 15 g of air in that 1 L of seawater. What volume of air would that be at the surface? Well, the density of air is about 1.29 g/L under normal circumstances. That means if you have 15 g of air, you actually have 15 g / (1.29 g/L) == 11.6 L of air at normal pressure. (That would mean that seawater actually contains more oxygen per unit volume than air at the surface does!)

According to your calculation (and your assumptions about what "1.5%" means), it would require 200 L of seawater to be processed at maximum efficiency to generate 3 L of breathable air (one breath), whereas according to my calculations (and my assumptions about what "1.5%" means), it would take only about 0.25 L of seawater. The one different assumption makes three orders of magnitude of difference in the answer!

Anyway, I'm not sure either of those conclusions is fair given the sparse information in the article. But, I am sure of one thing: it has to be possible, because all kinds of creatures (even really big ones) with aerobic metabolisms live down there. Sharks have gills, and it seems like they'd certainly use lots of oxygen, probably as much as a human if not more. Your 9000 liters/minute figure would have to apply to them just as it applies to this new machine, since it doesn't matter what means is used to extract the available oxygen. But, sharks can't possibly be filtering 9000 liters/minute (which equals 150 liters/second) of seawater through their gills and extracting 100% of the oxygen just to breathe, so there has to be more oxygen in the water than your calculations indicate.

Re:I am also a long time diver...

[andrewHYC]

Actually your assumptions are incorrect. The system doesn't need to supply 3 fresh litres each time you breath.

When you breathe normally the limiting factor is the build up of carbon dioxide, not the lack of oxygen. In a rebreather system the air is simply scrubbed of carbon dioxide and recirculated back into the tank.

You normally produce about 450 litres of carbon dioxide per day which equates to 300 ml per minute or about 20 ml per breath, and you use about the same amount of oxygen.

In this system all you would need to do would be to provide an exchange surface to get rid of carbon dioxide and to replace the few ml of oxygen that you used. This would only require a few litres of water.

The limiting factor is not water volume but surface area of the gas exchange surface. However with the development of new membranes over the last few decades this was an idea just awaiting development.

Re:I am also a long time diver...

[mental666]

Even at ~32 feet you are at 1 atmosphere extra pressure.

vs

Third, at 10m (~33 ft) you are at 2ATM pressure, not 1ATM!

At sea level on dry land you are under 1 ATM. If you dive down ~32ft you will be under 2ATM which is.... wait for it..... one EXTRA.

Re:I am also a long time diver...

[hanssing]

I did not check your calculation at sea-level.

BUT Henry's law tells you that the amount of dissolved gas/litre is proportional to pressure. I.e. if you need 10 litres of seawater/min at surfacelevels, you should need the same amount at depth. So this issue solves it self.

Re:I am also a long time diver...

[Suidae]

Personally, I think they should research more into completely bypassing lungs in the system. Folks could elect for bypass surgery that installed a machine in their chests, and blood would undergo the CO2/O2 exchange in the internal machine. The machine would expose plugs to the skin, and rechargeable devices could feed the required gasses.
Why not go all the way? Install a device that extracts C02 and other metabolic waste products from the blood and then, using an external power source, converts them back into O2 and simple sugars, essentally reversing the cellular consumption of oxygen.

This would make people electric powered for extended periods (how long would depend on how completely one could reclaim metabolic waste products and how long consumables in the process lasted). I'd imagine such a system would be useful anywhere it was expensive to carry food and oxygen (any extreme terrestrial travel or space travel).

Since average human power usage is limited to around a few hundred watts (with peaks somewhere upwards of a kilowatt) the battery pack required isn't too large for extended times. Not that much larger than a powerful laptop.

In some environments a nuclear source would be feasable. Standard RTGs can deliver nearly a kilowatt for decades. Scale it down to deliver around 2 kilo-calories to meet normal nutritional intake for a few months of operation and you'd probably have a fully internal power source that lasted for months, eliminating the need to breath and eat (at least in appreciable quantities).

Course, the biotech will need a few decades to do the research, but if we as a species can survive our own agressive and environmentally destructive tendancies, I wouldn't be surprised at all if technologies of this nature were developed.

Anyway, it makes for good features in a sci-fi story.

Prior Art

[Pepebuho]

Obi Wan Kenobi was using one in Episode III a long time ago in a galaxzy far, far away....

Yeah, right

[jackcarter]

In George Lucas' movie "The Phantom Menace", Obi-Wan whips out a little Jedi underwater breathing apparatus and dives in. As things tend to happen in our world, yesterday's science fiction has turned into today's science fact due to one Israeli inventor with a dream. Oh really? Then where the fuck is my lightsaber?

Re:Yeah, right

[joto]

Oh really? Then where the fuck is my lightsaber?

Are you a jedi knight? I guess not. That's why you don't have a lightsaber!

Re:Yeah, right

[SEWilco]

Jedi knights build their own lightsabers. We know why you don't have one.

Aquaman is PISSED!

[digitaldc]

Aquaman, shocked by the news of the invention of an underwater breathing device, has filed a patent infringement lawsuit against the inventor, alleging that he violated (at least) one of his patents for underwater oxygen extraction.
A wise-ass dolphin at the scene was quoted as saying Aquaman was already fabulously wealthy, and was 'just being shellfish.'

More likely...

[jd]

...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?

Truly Vaporware

[bill_kress]

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.

For all those worried about oxygen toxicity:

[geekyMD]

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.

Re:For all those worried about oxygen toxicity:

[Sam Ritchie]

Comparatively, nitrogen has very low solubility (which is why Guinness use to put a head on their beer). The centrifuge won't be producing anything like an air mix.

It's not particularly clear from TFA, but it's supplying oxygen to a rebreather system (which will subsequently handle gas mixing); the diver isn't breathing the output directly like an open-circuit (scuba) system. I imagine the system would still need a diluent (air/trimix) cylinder depending on what else can be produced from the seawater.

Re:For all those worried about oxygen toxicity:

[BCW2]

If CO2 is higher I'd be worried. 3% causes problems and 3.5% causes brain damage. I knew some of the stuff I learned on that Nuclear Sub would come in handy someday!

Re:For all those worried about oxygen toxicity:

[Anonymous Coward]

At atmospheric level, air is: ~73% nitrogen, ~23% oxygen, ~2% carbon dioxide, ~2% other,

Nitrogen: ~78%.
Oxygen: ~21%.
Argon: ~1%.
Carbon dioxide: ~0.04% (used to be ~0.035% before the Industrial Revolution).

Re:For all those worried about oxygen toxicity:

[Nyh]

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.

You don't recall correctly. The solubility constants of the most important gasses at 20C and p=p0 are:
O2: 1.38 E-3 mol/L
N2: 0.688E-3 mol/L
CO2: 38.8 E-3 mol/L
Note all constants are highly dependent of water temperature.

Nyh

Rebreathers...

[MrPower]

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...

[Anonymous Coward]

No offence intended, but somehow it's difficult to believe what someone is saying when they can't even count to three.

Re:Rebreathers...

[tongue]

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 the ambient pressure... rebreathers have actually been used to set world record depth dives. incidentally, the guy that taught me to dive at one time had the world record for deepest non-recycled dive (meaning they were switching out tanks with special mixtures as they went down.) when you're doing dives like that (I think he got to 987 ft.) you almost literally have to invent the science as you go--there's very little published literature on what will or won't kill you at that depth.

Re:Rebreathers...

[Anonymous Coward]

The usage of "Nitrox" for sport diving is oxygen RICH mixtures, generally 32% or 38% O2 for recreational diving. The advantage is less nitrogen absorption, therefore longer no-decompression times. As others have pointed out, the disadvantage is depth limitations due to oxygen toxicity. A partial pressure of 1.4 atm O2 is the general "do not exceed" limit.

I am nitrox certified and experienced in making, testing, and using my own mixes.

A closed circuit rebreather that I have been trained on (by an ex Navy SEAL) maintains an oxygen partial pressure of 1.2 atm. The practical limit on dive time with that particular rig is cold or boredom.

Raising the % of Nitrogen (and therefore the partial pressure at depth would be insane, as you'd get a double whammy of increased nitrogen absorption causing both shorter bottom times / greater decompression requirements, and increased likelyhood of nitrogen narcosis. That is why mixes used for sustained dives below ~150 ft. use Helium, Argon, or other gases for the "bulk" in place of Nitrogen. These have other, different side effects that have to be dealt with. "Mixed Gas Diving" if I recall the title correctly is an excellent book on the topic.

Re:Rebreathers...

[JebusIsLord]

Helium has an advantage in that it is a lighter gas, and that makes it easier on the body for various reasons at high pressures.

Re:Rebreathers...

[rderr]

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. Wrong... http://www.gasdiving.co.uk/pages/misc/Nitrox.htm#1 -Rob NO CARRIER

no, rebreathers are very different...

[choongiri]

...they work by using a closed circuit of air that is continuously being scrubbed of CO2 and at the same time oxgyen is added from a tank of pure o2. the only possible benefit of this technology to rebreathers might be to extend the potential dive-time by supplementing the pure o2 in the rebreather tank. however, since rebreather technology already alows for dive times of many hours, i think that's unlikely

Won't work..It's all about pressure.

[Anonymous Coward]

I'm very sceptical that this device will be much use . One of the primary reasons for breathing compressed air is so you can actually take a breath at depth.

You increase the ambient pressure one atmosphere (14.7 psi) every 33 feet in salt water (34 fresh water). This extra pressure makes expanding your chest cavity to take a breath very difficult without a high pressure source to breath off of. The whole reason for the first stage of any regulator is to match plus 1 or 2 psi the ambient pressure to compensate for the squeezing pressure on your chest.

At anything below 33 feet your going to expend most if not all of your energy just trying to take a breath.

Re:Water doesn't hold much O2

[Anonymous Coward]

You know, water just doesn't hold that much O2. Fish farms have to aerate the water when it gets cold.

I can't imagine that this Rube Goldberg device will be more efficient and reliable than a small O2 tank rebreather.

Tankless work?

[game kid]

I told choo tree times, TREE TIMES, stop making funo my akhcent, boi. Dawn mek me hit choo wit tee keyboar mon.

...but really, this is the first I've heard of it. If I get one, I might even teach myself to swim...

it's the battery that's friggin lethal

[wsanders]

FWIW, yes - no compressed air is needed in this rig. Maybe a little - TFA describes an "air bag". I was tought your lungs can handle about 2 psi max before you embolize, which is why you can die in the shallow end of the pool if you hold your breath and ascend. Not hard to make a plastic bag to hold 2 psi.

But a "one kilo lithium battery" is a frickin bomb waiting to go off, especially considering it is immersed in salt water. The lithium battery in your cell phone is only a few ounces.

Of course not as lethal as a 3000 psi scuba tank going off. I was taught to handle the tank by the valve. I saw the aftermath of some dumb ass who threw a tank in the trunk of a car valve first. The valve broke off and the tank was launched through the side of the car and punched a 2-foot hole in a cinderblock wall. Nobody got hurt thank god and luckily I wasn't around when it happened ...

Should This Get A Patent?

[ObsessiveMathsFreak]

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.

incorrect on many points

[SuperBanana]

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.

Recreational diving using Nitrox has reduced this drastically to where the limits are back to the amount of gas you can take with you.

Pure O2 is poisonous below about 32feet, if I remember correctly and if you go below about 100feet, just depending you can get high.

No. Below 32 feet on O2, you can go into involuntary spasms, and drown. It's the primary danger with rebreathers, which is why they have usually two O2 monitoring devices on them.

The "high" is on regular air, and is called Nitrogen Narcosis. It is very dangerous because it makes you very emotional and severely disrupts judgement. Not so good when you need to make a controlled ascent...

I don't see how the contraption can both be small and deliver at a high pressure while operating off of one battery.

Air in the tanks is compressed to give the most capacity, not to match depths. 34 feet of water is equal to 1 ATM (14 psi) so at 100 feet (2.94 ATMs), pressure is 41PSI.

Each breath is 3 times the volume of a surface breath, so a 3000PSI tank which held, say, 1000 breaths at the surface, now holds only 333 breaths (totally making up 1000 breaths, btw).

Even at ~32 feet you are at 1 atmosphere extra pressure.

Yeah, and so's the oxygen in the water, which you are extracting. Under pressure, more oxygen can be soluble in water. That doesn't mean there IS more oxygen in the depths. In fact, this contraption would be very useless in some waters where other gasses are predominant (like, say, around a volcanic vent). Dissolved O2 levels vary quite a bit.

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.

They're not pure O2. They're rebreathers- although there were pure O2 rebreathers many years ago. State of the art has advanced considerably.

A few corrections:

[ThunderBucket]

Size of the tank absolutely determines time underwater. I think you're confusing tank size with no-decompression limit, which is the function of depth, breathing mix, and time that determines when you're no longer safe to go to the surface. Recreational diving mandates that you stay within the no-decompression limits. This way, if you do something stupid, as many rec divers do, you can surface immediately and still be OK, at least according to the gas-loading models. Contrast this with decompression ("technical") diving, where you accumulate enough nitrogen in your body that if you surfaced you'd have a substantial risk of decompression sickness (DCS). To get around this, you can mix in more oxygen, so as to limit your nitrogen uptake, but a higher partial pressure of oxygen means more risk of central nervous system toxicity (see below)

Having this device wouldn't prevent you from doing decompression diving. In fact, depending on how much pure O2 it could generate pre unit time, this may be a natural addition to a rebreather system, like the one you mentioned. (Navy SEALs use ones by Draeger, but there are much more user-friendly ones available from Halcyon, among others...)

What exactly is the problem with the device providing O2 at ambient pressure? The reason SCUBA tanks are at 3000PSI is to store more air, not because we go diving in 6000' of water. The reason you have a regulator is exactly as you said: to modulate the pressure down to ambient levels. If the device produced air at ambient levels (and without a pressure tank, it pretty much has to), there wouldn't even be a need for a regulator, except for your bailout bottle in the event something didn't work.

And be careful: Oxygen toxicity happens with alarming frequency at 1.6 atmospheres of pressure, or 15' of water. Breathe pure O2 at 32' and you're in for a ride on the seizure train. Nitrogen narcosis ("rapture of the deep") occurs between 90 and 150', typically, but it affects everyone differently.

I'd highly recommend to the interested reader the NAUI Advanced and Master-level dive courses, in addition to recreational nitrox.

Re:Amazing that someone didn't think of this befor

[pthisis]

I had the by-hand RK about 10 years ago...certainly that would've been doable decades ago if somebody had thought of it

[Ugh, by-hand RK was obsolete 15 years ago (by the late 1980s/early 1990s PRK had replaced it).]

My dad's an opthalmologist.

It was done widely decades ago. Hell, even Consumer Reports was running articles comparing RK and PRK more than 10 years ago.

And even longer ago, someone had thought of it. Herman Snellen proposed it in the 1860s. (he's the same guy who invented the modern eye chart). It was tried off and on for a while, but with no measurable success until the 1930s.

A Japanese doctor (Sano or Sato?) performed RK on dozens if not hundreds of patients in the 1930s and 1940s to successfully correct myopia, but there were long-term problems with corneal degeneration--the incisions went through both the anterior and posterior cornea, and corneal clouding eventually resulted in many cases.

But by the 1960s, lamellar surgery (more similar in method to modern LASIK) had come into vogue as the preferred method of surgical vision correction. The technique was developed in Colombia, but spread elsewhere.

Then in the 1970s Russian scientists (Fyodorov and his compatriots) determined that RK could be effective even if limited to the anterior cornea, making it safer than the earlier methods and greatly reducing the corneal clouding issues. They also limited the number of incisions and increased the control, making it subtantially more likely to succeed than the earlier methods.

The focus for real-world surgery switched from lamellar to RK.

It still wasn't super-high percentage, so photoreactive RK (PRK) using a laser followed in the 1980s, followed by a return to lamellar surgery using a laser (LASIK) in the early 1990s.

I think LASIK is the only one to have ever had FDA approval, and that was pretty recent (c. 2000).

Think Simpler

[Effugas]

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.

Re:Think Simpler

[FridayBob]

"... without having to maintain scuba gear would be rather cool ..."

Oh, and you don't think this thing would need any maintenance? Think again. It's got batteries, it's electrical equipment that has got to work underwater and not short out, it's got moving parts, it'll have a fair number of O-rings to check and replace. It's also got to suck in a lot of water, so you'd better hope that it's got an adequate filter so it doesn't get clogged up too quickly. If that happens, all you'll have to get you to the surface is that teensy little bail-out bottle that looks like you'll get about two breaths out of it. Oh, and that bail-out bottle means you'll also be carrying all the normal SCUBA equipment: first and second stage regulators along with a tank, even if the latter is small. So, it's definitely not that simple, even for shallow dives.

Re:Amazing that someone didn't think of this befor

[pthisis]

Googling around, there's at least one succesful surgical correction of astigmatism from 1895 (Dr. Faber).

The Japanese doctor is Sato.

And LASIK was FDA approved in 1999. And PRK had pre-market approval in the early 90s but never got full approval.

Dr. Joachim Barraquer of Colombia originally developed the lamellar technique in the 60s and 70s, and it was greatly refined in the 1980s by (Colombian) Dr. Luis Ruiz. The technique essentially became the modern LASIK technique.

It extracts "air" not just oxygen!

[517714]

The device mechanically separates all the dissolved gases in the water from the water, so oxygen toxicity should not be an issue - the mixture of dissolved gases will generally be close to that of the atmosphere. I wouldn't try using it near a "black smoker" or methane hydrate formations though as the "air" would be a little unpleasant.

Re:It extracts "air" not just oxygen!

[Chess Cardigan]

Except that the ratio of gases dissolved in the ocean is different to that of gases in the air. Oxygen makes up about 35% of the gas dissolved in the surface water of the ocean. So given that Oxygen toxicity kicks in at about 1.6 atm partial pressure, that would be at about 35 metres underwater.

From http://seis.natsci.csulb.edu/rmorris/oxy/oxy4.html


The three major dissolved gases in the surface waters of the ocean are oxygen, nitrogen, and argon. The ratio that they exist dissolved in the ocean is not the same as is the ratio existing in the atmosphere. The ratio of O2:N2:Ar in the surface waters is approximately 20:36:1 [5b]. The atmospheric ratio of 21:78:1 shows that more oxygen gas dissolves in the sea than does nitrogen gas. Nitrogen gas is not as soluble as oxygen and argon, so when water releases its dissolved atmospheric gases, the air becomes relatively enriched in oxygen.

Re:Amazing that someone didn't think of this befor

[gl4ss]

the area with decreased pressure is the area at the center/inlet, i'd presume.

what's to note is that apparently this technique hasn't been used in diesel submarines.

though, it's just a prototype so far.

Re:Water doesn't hold much O2

[NeoSkandranon]

IIRC cold water holds more O2 than warm.

Hard number and facts for you.

[Anonymous Coward]

Rapture of the deep or Nitrogen Narcosis is caused by nitrogen under pressure, not oxygen.

Nitrogen at depth acts as a narcotic and can cause divers to see things and/or act irrationally.

Oxygen becomes toxic at approx. 6 atmospheres of pressure or just under 200 feet. Recreational diving is in less than 30m of depth.

At sea level 33 feet of salt water or 34 feet of fresh water is equal to one atmosphere or 14.7 psi.

Bends is caused by nitrogen dissolved in the blood much like a soda bottle with dissolved CO2 in it. At depth the amount of absorbed nitrogen increases in your blood. When surfacing and thus decreasing the pressure will cause the nitrogen to leave a solution and form bubbles in the blood and soft tissue. Imaging opening a soda really fast. Exact same thing.

The term Safety Stop refers to a diver stopping at certain depths for a time to allow the nitrogen to be expelled or 'out gased' slowly through respiration (Slowly opening a soda bottle thus not creating the bubbles that would form otherwise).

James Bond

[medgooroo]

Definetely remember 007 having one of these toys... always thought they would be cool

Units of pressure

[ari_j]

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 would hurt.

Re:how long will it take for someone to use this t

[Optic7]

Swimming underwater will take a great deal more effort since more body frontal area is exposed to water, which is denser than air.

I'm no physics wiz, but it doesn't seem to me that that is the main reason why swimming underwater is much less efficient than swimming on the surface, given that when you swim on the surface most of your body is submerged anyway.

I would imagine it has to do with half of your stroke cycle when swimming at the surface cutting through air, instead of water for the full cycle. This would force the underwater swimmer to adopt a less efficient stroke than the regular breast(?) stroke. Maybe also a little bit less drag effect on the back of the body exposed to the air as well. Just a guess though.

Not quite..

[StikyPad]

From TFA: Nuclear submarines and the international space station use systems that generate Oxygen from water by performing 'Electrolysis', which is chemical separation of Oxygen from Hydrogen. These systems require very large amounts of energy to operate. For this reason, smaller, diesel fueled submarines cannot use these systems and are required to resurface to re-supply their oxygen tanks every so often.

Although it is true that having a higher electrical load would decease the time it could remain submerged, the reason diesel subs don't bother with electrolysis is not because they can't, but because they run on batteries when submerged, unless they're at snorkel depth. As it turns out, it's difficult to run an internal combustion engine without an ample supply of air. Since they have to surface to run the diesel and charge the batteries, there's little point in using electrolysis to produce breathable air, since air isn't the limiting factor in how long the sub can remain submerged.

Re:I've read 'rapture of the deep,' and...

[Anonymous Coward]

Thank you. I have seen the light. Please help me now - I have plenty of upper body strength. How can I go about in a form of rape that is more pleasing for me?

Depends on the curvature

[tepples]

If you swim 20 feet below the surface of a sphere, you cut 20 feet off each radian that you swim. On earth, a radian is over 20 million feet. Thus, the distance saved (roughly 0.0001 percent) would be insignificant.

A more likely path to investigate: Is underwater swimming faster than surface swimming?

ob: simpson's quote

[Anonymous Coward]

...

Homer: [fearfully] Marge? Kids? Everything's going to be just fine.
No go upstairs, and pack your bags...we're going to start a new
life...under the sea.
[calypso music starts]
[Homer dances with fish as Lisa plays a seahorse saxophone,
Marge a squid harp, and Bart the xylophone clams]
Homer: [eats a dancing fish, sings]
Under the sea, under the sea,
[eats a couple more fish]
There'll be no accusations, just friendly crustaceans
Under the sea!
[eats a line of seahorses, grabs an escaping one]
[eats a live crab as though it were a shrimp]
[eats a pair of dancing fish, then a snail who tries to escape]
[stands there with fish skeletons floating about]
Marge: Homer, that's your solution to everything: to move under the sea.
It's not going to happen!
Homer: Not with _that_ attitude!
-- The little Homer mermaid, "Homer Bad Man"

Marge: Look, maybe this whole thing will blow over.
[helicopters swoop over the house; news vans pull up]
Homer: It didn't blow over, Marge. Nothing _ever_ blows over for me.
[the car gets flipped by the wind from the helicopters]
-- They only blow over literally, "Homer Bad Man" ...

One word

[plgs]

Oxygum! (Because everyone remembers Marine Boy).

James Bond's was better.

[Anonymous Coward]

Q's invention is much better. It is only the size of a large pen, and Bond was able to fight through an entire undersea battle with it.

Re:how long will it take for someone to use this t

[Anonymous Coward]

Just use those friggin' huge paddles on yer feet, dammit. Swimming with them is so much faster than with your bare arms and legs combined. That's why frogs and fish have them and we copied it.

Re:Not old hat, RTFA

[Anonymous Coward]

The parakeet thingy was demonstrating passive diffusion. This isn't the same.

If you RTFA you'll see that his technique is active. The gas is physically extracted from the sea water using a centrifigul pump to lower the pressure and let the gas bubble out like foam from a coke.

It's quite clever really.

What if you lose power?

[kkith]

WIthout the centrifuge generator then no O2. F*cked.

Gee Thanks Greg...

[Anonymous Coward]

... Now I never want to try scuba diving!

Re:Gee Thanks Greg...

[Anonymous Coward]

Why not, it's a wonderful experience. I just wouldn't recommend diving in inland UK (quarries like Stoney Cove) cos it's bl00dy freezing and vis is virtually nil. I just can't believe there are so many /.ers who are fully qualified divers. I'm still a relatively inexperienced diver tho am qualified at advanced level with deep and multi level certification.

No kidding

[kitzilla]

> 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

[BCW2]

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. difference full to empty. That is a bit much to deal with without a BC. The BC works just like the trim tanks on a sub. Instead of adding or subtracting water, you do it with air to maintain neutral bouyancy. That way you don't waste energy trying to maintain depth, which burns up the air supply faster.

Yuh Huh

[Greyfox]

I wonder if the device also separates chlorine from the water. That'd be nasty. Not to mention breathing third grader pee...

Patented?

[Anonymous Coward]

If it is like Fish Gills" design, why not patent the entire fish thing. If the advances in the technology permit what every scientist thought off for the last 1000 yrs, I do not see how people can patent it.

I may misunderstatnd the patenting thingy, but some things are far fetched.

To clairfy on gas fun with recreational diving...

[jameslore]

To clarify, the bends is related to pressure differential. Ascend slowly and let the pressure equalise and you'll be fine. Ascend too fast and you get bubbles, leading to all sorts of fun, including potential embolism. Yum.

Pure O2 tolerance is dependant on the individual, but for Nitrox (more 02, less N than air for rec diving) 1.4ata is considered safe, 1.6 is considered dangerous and over 1.6 is considered suicide. Compressed air becomes unsafe at about 50m and Nitrox even earlier. tech divers use all sorts of curious mixes to get well beyond this level. Pure 02 becomes unsafe at about 4m, which still allows technical divers to use it as a decompression gas.

And you can get high (narked) at any depth on standard air, although it generally occurs below 30m. Completely harmless in itself and disappears upon ascent. As long as you don't try to talk to the fishes...

Cool tech

[rice_burners_suck]

All of the most amazing things are invented in Israel. It's almost cliche now! Just like launches to space. Used to be a spectacle for the whole world. Now, who cares? Same for Israel and technology. Nobody pays attention when some new whiz-bang thing like this comes from the land of Jesus.

Maybe because the biggest miracle of all is that this tiny democracy can even exist when literally surrounded by so many enemies that wish for its destruction. Drives me nuts how people can be so shortsighted.

Re:Take your last breath and not die!

[Anonymous Coward]

That's what flash is for, duh!

Re:how long will it take for someone to use this t

[StarsAreAlsoFire]

Um. Ever watched olympic swimming?

Being fully underwater is at least a factor of 5 more efficient than being on the surface.

Its all about breaking the surface tension.

b.) negates a.), and isn't an issue; the few pounds that would be required could easily be streamlined, and would be but a tiny tiny issue compared to the drysuit/6mm wetsuit you'd have to wear to avoid dying of hypothermia.

I'm just waiting...

[jswalter9]

I'm just waiting for the stupid US patent office to deny the patent while it hands out software patents like candy.

Re:Swimming underwater will take a great deal...

[maxume]

Which is why there are none of those pesky creatures that swim underwater.

I admit to not understanding the fluid dynamics very well, but I imagine the biggest benefit for a human swimming on the surface is that he can drag his arms through the air on the return stroke rather than the water. If that is what you meant by 'more body frontal area is exposed to water', you have my apologies.

Also, if you are neutrally buoyant, all you need to do is make sure that your dive weights are streamlined and they should have a minimal impact on the energy required for the swimming(you are fighting friction, not inertia).

2000 litres a minutes

[Anonymous Coward]

Read the patent - this baby has to pump 2000 liters a minute through its gas separator. It even proposes that the expelled water can be used as a propulsion system.

Im thinking that 2000 liters a minute is a huge amount of water moving power. Maybe equivalent to the output of a jet boat.

Nice thing to have strapped to your back. Probably need to carry along enough oxidiser to make it run for any length of time. Doh!

Re:Take your last breath and not die!

[Anonymous Coward]

Personally, this sounds a bit fishy.

Thank you, thank you, I will be here all week.

Innovative...they are not!

[Johnny Mozzarella]

Standard issue for Jedi... these devices have been.

Let's assume it would work...

[FridayBob]

If it really would be possible to create a SCUBA system based on this invention, would it really be so much better than the technology currently available? I'm not so sure.

** Complexity **
If this thing ever does hit the market, it'll be for technical divers only. After all, we'd be dealing with electrical life-support equipment underwater, which is always problematic. Not so much that you might electrocute yourself with it, but simply that it can short out. That would leave you without your main gas supply. Also, it sounds like this thing it going to be processing quite a bit of water for every liter of air it produces. That means that you're going to want to use a pretty big filter, or else the water flow through the centrifuge could quickly become significantly reduced or even be blocked (I don't like this already). Not exactly a recipe for a simple and worry-free system.

** Bulk **
Selling this thing as a way to reduce bulk not going to work. To begin with, you won't be able to use those li-io batteries in place of your lead weights: they're far too light. Hell, if they float, you'll need to take even more lead with you. Lead-acid gel-cell batteries might be a better idea.
Second, technical divers usually like to dive for much longer periods than recreational divers, usually much deeper as well. That means they're always going to take bail-out systems with them as back-up, like spare tanks or even a rebreather. This bulks up things anyway. By the way, the bail-out tank in the picture is way too small.
Third, how many liters of air will this thing actually be able to produce per minute? Enough for anybody to breathe from it directly? You would hope so. If not, well then to get your batteries to last longer, you might want to make this thing part of a semi closed-circuit rebreather system. This is a good way to stretch any limited air supply, but in this case it would add more bulk. Remember, every semi closed-circuit rebreather requires hoses, breathing bags (lungs) and a CO2 scrubber cannister.

** Performance **
Only one hour per kilo of li-io battery? An AP Valves Inspiration rebreather (electronic, fully closed-circuit) will get you at least three hours under water -- even more, depending on how far you care to push the CO2 scrubber. To compete, somebody flying mr. Bodner's underwater wonder would need at least three kilos of those (expensive) li-io batteries. These will be quite bulky too, especially in their sealed cannisters.
Diving really deep (70m and beyond) with this thing is not going to be possible either. Deep diving with SCUBA equipment always requires the use of Heliox or Tri-mix -- gas mixtures that include helium. But, since this centrifuge thing is only going to extract normal air (oxygen and nitrogen) from the water, and adding helium to the mix as you go is out of the question, this will pretty much limit its use to recreational depths.
The worst, however, will be the noise. With normal, open-circuit SCUBA, the noise made by a group of divers exhaling can almost be deafening (scares many fish away). As far as I can tell, this new device is going to be open-circuit as well, so that will be bad enough. However, with this thing, it sounds like you're also going to have to put up with a whining centrifuge on your back as well. Unless they can do something to muffle this sound, it's bound to get on your nerves (or someone else's) sooner or later.

** Price **
Finally, you know this kit will never be cheap. It will come with a lot of parts: electrical parts, moving parts. For a manufacturer to get anything like a CE certification for a diving apparatus like this will cost a small fortune. This could easily end up doubling the price, which would place it firmly out of reach for most of us.

** Conclusion **
I'm not so sure this thing is going to create any big stir in the diving community any time soon. It'll probably remain be a novelty at best, kind of like a pure-oxygen rebreathe

My what?

[Anonymous Coward]

Dear MikeHunt69 (695265),

I believe MikeHunt is talking otherwise out of his proverbial ass. Also, stop building sentences with so many periods; use some exclamation, or keep the thread alive with a question! What's that I hear? You're pregnant? With bullshit you say!

PS: this post is masonic to the hilt: containing a dimension of words used in another context and intentions not relative to common english.

Sounds good and all, but...

[ImaLamer]

Too bad Darfur is a landlocked region.

You are wrong. Patents are for commercial purpose

[NRAdude]

This post is an in-vent to a slashdot forum.

Arguing aside, deception of commerce notwithstanding: Anyone can duplicate this technology directly; patents apply to when the matter/IP is deeded to another for profit or commercial activity (both are different scope). There seems to be a misconception that patents prevent people from duplicating ideas for non-commercial use. Patents don't limit non-commercial use of other property that is not part of the patent. Many of you should be wondering why I explain as though patents have no effect, but it is not what I meant to say; patents are used to prevent derivatives, piracy, and whatnot; competitors duplicating a techique and selling or brandishing it in reference to another technology. Where the line between commerce and not commerce (lawful) begins is the dispute that has encroached on many people in the form of the New Deal created by then President Franklin D. Roosevelt. I like to say that there are instances when companies buy out eachother for similar reasons, unlawfully asserted; given one example, Microsoft incorporated buying a Canadian (IIRC) company known as Mike-Rowe Soft.

If you own it, pull off all the trademarks and dedicate it for non-commercial purposes with a deed. If you build it, do the same; get it out of the commercial venue; that none is for sale. The same is to be done with a Motor Vehicle: return the Certificate of Title to the DMV, ask that the record of the original title (MSO/MCO) be junked and the record purged; it Now is not a Motor Vehicle but a car, so pull off all the trademarks on the car, issue a Bill of non-Sale with witnesses, print your action in a newspaper, build some character on your unalienable right to travel with supporting case-file and history, 7)non-PROFIT!

water pressure is the same

[Anonymous Coward]

he water pressure at your level is the same as the pressure on your body, so there isn't any big pressure difference to overcome if the device uses the surrounding water.

The extra pressure on the O2 tanks is needed because they are solid, so their contents is not subject to the same pressure.

Birdshit down my snorkel.

[Anonymous Coward]

I was once snorkeling and a seagull shit on my snorkel tube as it was above the water. I just had this horrible taste in my mouth, went above bar to see wtf any bastard nearby had done, and it was this horrible mass of spooge at the top of the tube and sunk into bottom in the bend of the snorkel. It sounded like a straw in an empty soda. Just horrible man.

Also, I hate people that have the urge to stick their goddam fat fingers in my snorkel when I'm looking around. just the feeling of someone suffocating me is instant death delivered by my clam knife. I'll cut their fucking hear out and use it as halibut chunk bate, I swear to God I hate when people or seagulls do that to me or anyone for that matter.

Re:how long will it take for someone to use this t

[lelitsch]

Uhm, no. I swam competitively for about 8 years in school and been scuba diving on and off since. You are swimming more efficiently under water because you don't break the surface and because you don't create a bow wave. This is exactly why you are only allowed one underwater stroke at the start in all national and international swimming competitions.

The same is incidentially true for nuclear submarines which can cruise faster when fullu submerged.

Unless you can breathe chlorine

[Greg Hullender]

Unless you can breathe chlorine,I think this might not be so great in a pool . . .

--Greg

Re:Unless you can breathe chlorine

[Vegeta99]

Chlorine is present in pool water as ions, so this thing wont pull it out.

Re:Unless you can breathe chlorine

[Boronx]

When I was kid there was this one hottub where they left the plastic cover over part of it. Some of us would get under that cover going for a sauna effect. After only a minute or two, some gas truly irritating to the lungs would build up and we'd have to flee. Always figured it was Chlorine.

Still SCUBA

[ebvwfbw]

Did you RTFA? It is still self contained, needs no external hoses or wires and it is an underwater breating aparatus. So even though it doesn't use tanks, it is still a SCUBA setup. Jacques Cousteau would be proud! I bet he would even volunteer to try it if he were still around.

BTW you can go deep for long. You just have to watch how fast you come up. Didn't they teach you about the levels and time tables? They should have if they didn't. I have been known to dive with a just a bathing suit to 30 feet. Maybe you meant 30 meters? The deepest I know of is 313 meters but I know people that regularly dive up to 100 feet.

This new setup has a 1 KG battery. Should help with that raft they call a wetsuit! At least my wetsuits seems like a rafts, some more than others. I hope a BC can compensate in warmer waters.

A centrifuge?

[zbuffered]

In that case, why not have a small crank for emergency use when the battery dies? The image this conjures up in my head is just priceless!

old news

[Tom7]

Man, we have had this in DOOM for like 10 years.

I find that pretty cool...

[daviq]

Is this the key to the future...the technologies are nice, but can it acutally handle the amount of air needed by a human--> even a human using lots of oxygen...also, can't oxygen be harmful if taken in in it's pure form. Does that mean you need to carry a carbon dioxide tank with you. I don't think that the world is ready for this yet

Re:I find that pretty cool...

[Vegeta99]

it's air that's dissolved in water (like CO2, N, etc..) so you get more than oxygen out.

Re:Disagree, think it could find a hold in rec div

[bill_mcgonigle]

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 much worse), but by time I did my ascent and was able to turn off my tank it was pretty much empty. The boat was a good 1/8 mile away and there were 7 foot seas. Yay. The divemaster was already around the ship so he didn't notice (perhaps he should have).

Fortunately I had grown up spending my summers in the ocean and had trained as a Boy Scout lifeguard (3 2-mile swims a day) and was trained to dive by a mean old Libertarian from Vermont so I was able to get back to the boat without air (it's a bitch swimming on the surface in full dive gear). But I can easily imagine less fortunate outcomes with your average cruise-ship certified diver.

Having an essentially limitless supply of air would let him hang neutrally boyant just below the surf for a very long time, at least long enough for a divemaster to figure out where his diver went to. I don't have my charts handy but he could probably hang something like a couple hours without too much risk of pressure sickness. Heck, if were small enough might as well carry one as a backup on SCUBA dives.

Opera's CEO Jon von Tetzchner has promised...

[craXORjack]

that if Opera 8 is downloaded a million more times in the next four days that Eskil Sivertsen, his Public Relations Manager, would swim across the Atlantic underwater using the underwater breathing apparatus. Tetzchner says, ' last time I made a promise my body couldn't keep but this time I'll be rowing the boat, so I feel much more confident.'

The flaw in this is reasoning is

[Anonymous Coward]

assuming 1.5% vol/vol. The article does not say but I'd guess mol/mol or mass/mass

See http://www.engineeringtoolbox.com/air-solubility-w ater-24_639.html

Jedi Beat him to it.

[ananegg]

As we've seen from Ep.1 The Jedi have had these for years. Now if this guy had invented somthing that would kill those pesky gungans................

star wars

[guorbatschow]

just wait till those devices get sophisticated like those used in star wars. remember the scene when quigon and obiwan dive to the gungan city?

Battery Issues...

[rubberbando]

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.

Just put a little dynamo on it so you can recharge the battery somewhat in an emergency. :)

Re:Amazing that someone didn't think of this befor

[TapeCutter]

I watched Marine Boy in the 60's and I am still waiting for this type of thing to get off the drawing board.

Re:Not old hat, RTFA

[proteonic]

It occurs to me that this technology wouldn't be the best thing in even mildly polluted water. What's to stop pollutants from being extracted along with the air? I'm not sure if the same caveats would apply as for tank diving. Air must usually be filtered, since small amounts of hydrocarbons, or CO from a truck parked next to the air intake, could kill the diver when inhaled under pressure.

Low Battery

[benw1979]

This gives your Low Battery light a whole new meaning :)

Re:Disagree, think it could find a hold in rec div

[F34nor]

You might also be able to generate enough current for it to last alot longer, dynamo, etc.

Comment removed

[account_deleted]

Comment removed based on user account deletion

English Channel

[Kamic]

It says right on the website that you can't use any artificial devices.
With patents in Europe and the USA how long will it take for someone to use this to swim the English Channel underwater?

Divers don't dive with oxygen tanks

[Anonymous Coward]

Maybe he's system works, but he REALLY should get his facts settled first.

Divers use air in their tanks, not oxygen, due to partial pressure pure oxygen get critical for your body beneath 6 meters of water !!
We only use pure oxygen for decompression diving, and then only at maybe 3 meters of depth.

Actually if you do technical diving (trimix) you have maybe 4% oxygen in your tank, a lot of helium and a lot of nitrogen.

Go search wikipedia for more explanations.

Big deal

[erc]

Big deal. We were doing this 30 years ago. The Navy had a similar rebreather they were testing about 1974 or so. It used a small pump to run sea water over a thin gas permeable membrane that would allow oxygen to pass through one way while allowing carbon dioxide to pass the other. The gas permeable membrane material was made by General Electric, if memory serves.

Re:Big deal

[aXis100]

RTFA, this is not a rebreather. Rebreathers are still limited by the main oxygen supply.

This unit extracts dissolved air from the water, so the limit is purely how many batteries you can carry.

Re:Big deal

[erc]

RMFP, what I described extracts oxygen directly from the water, too.

-1 misinformative

[XNormal]

Nitrox has a higher percentage of Nitrogen, not oxygen...

Nitrox is a breathing gas consisting of oxygen and nitrogen (similar to air), but with a higher proportion of oxygen than the normal 20.9%... (Wikipedia Nitrox entry)

This thing runs on batteries?

[^DA]

I'm very sceptical to using batteries under water. In fact I think I can say that i'll never use a diving system that depends on batteries. It just feels unsafe.

The amunt of time you can spend under water isn't usually limited by air supply, but by nitrogen levels in your blood and tissue. http://en.wikipedia.org/wiki/Decompression_sicknes s

After about the 20'th dive running out of air has never been a problem for me. Now I usually surface with well over half the air left in the tank. The limit is the nitrogen saturation.

If you never go below 10 m this could be a cool thing if it weren't for the batteries...

Hope it has a backup system...

[sticky_wicket]

...because a short out or motor failure at 60 feet could put a real damper on your dive. I'm not sure how the complexity of this system compares to SCUBA, but it seems like there are several potential points of failure.

Re:Hope it has a backup system...

[BigTunaCan]

RTFA It shows a backup air supply in the primary diagram for crying out loud.

Re:Disagree, think it could find a hold in rec div

[passthecrackpipe]

dude, i so know what you are saying - I used to be a heavy smoker for many, many years, and my air consumption is - even today - simply staggering. I refuse however, to break up a group, so I usually inform the dive leader that i'll probably chew through my air in about 30 to 45 minutes, and will break off early.

Burning Diesel & Oxygen : is there a link?

[supertsaar]

From the article:

...These systems require very large amounts of energy to operate. For this reason, smaller, diesel fueled submarines cannot use these systems and are required to resurface to re-supply their oxygen tanks every so often...

I doubt that you could generate oxygen burning diesel, run your diesel engine with this oxygen AND have some spare oxygen to breathe as well.

But the amount of energy required is irrelevant in this case. A diesel is a_combustion_engine, dûh....

what happens when you use up all the oxygen?

[z0idberg]

I wounder if they have done any tests on the amount of uasage of air in the surrounding water? I dont know if I would be too keen on spending a lot of time in an enclosed wreck dive or cave dive with a couple of other divers. I imagine a few divers could use up the dissolved air pretty quickly. I would hope there is some kind of sensor/monitor keeping an eye on how much air/oxygen is in the surrounding water so you know when to move on.

Another thought, what about the effect on the sea life at high traffic dive sites. Usually popular dive sites have a lot of sea life, which also rely on the oxygen levels in the water. You get a lot of people in there using up the oxygen as well the little fishies mightn't like that!

they're going to put this where?

[spamchang]

where are they going to fit a centrifuge in a vest? and how fast does the 'fuge have to spin in order to lower the pressure enough to release air? that's going to be like carrying a little gyroscope that doesn't want to move around with you while you're swimming.

FailSafe: Batteries Fail, Scuba tanks ALWAYS work

[Anonymous Coward]

You are merrily swimming along underwater, and suddenly the battery or motor, or something else fails, choke cough, and you drown and die.

Oh sure, emergency ascent, or skimp on decompression, but no battery device comes near the sure thing of a tank. I could bore readers with 1st stage and 2nd stage, but conventional stuff is reliable, a genius simplicity.

Nitrogen takeon and getting cold are the present scuba limiting factors followed by the cost of insurance. Saltwater and batteries do not mix, and a marine environment kills all gizmos dead.

Nice try, but the truth and details are missing, the energy in a 70' steelie, is a whole lot more than one batteries worth. For surface work, an 18' snorkel works wonders - no batteries needed.

Even at sea: Put on something little more metal!

[Anonymous Coward]

Problems with the advertised method:
A., Decompression issues still apply
B., If you stop swimming, gas flow stops and you die, just like sharks do.
C., If you swim, sharks will notice you and eat you.

There is a better solution, a light armoured diving suit with rebreather, that takes care of all three problems. That is true high tech, see here:

http://www.nuytco.com/exosuit.html

Are you sure?

[camiosway]

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

Ok, the French and English hate each other. So apart from bombing the other one to death, why would anyone else want to do that?

Re:how long will it take for someone to use this t

[shimmin]

Swimming underwater is more efficient, which is why fish do it. On the surface, you have a wake, which is much worse drag than simply moving through a viscous medium.

Science fiction to fact, by one person?

[Jimbo God of Unix]

"As things tend to happen in our world, yesterday's science fiction has turned into today's science fact due to one Israeli inventor with a dream."

OK, so this is nit-picking, but this makes it sound like they're attributing all the way out inventions to this guy.

Contraindicated

[BurritoJ]

Isn't breathing underwater considered drowning and as such voids the warrantee on you lungs?

Big Deal

[Coco Lopez]

I saw this on an episode of Johnny Quest once.

Jedi...

[Conanymous Award]

...can already do this.

Wonder if the patents of a galaxy far, far away can be enforced here?

Not so.

[Anonymous Coward]

Your body is virtually all water and as such is mostly incompressible so would tend to take on the pressure of the surrounding water without material effect. There are of course a number of points in the human body that contain compressible tissues, namely the middle ears, the nasal sinuses, trachea, bronchia, lungs and spaces around joints of endochondral bones (those that grow at their ends via ossification of cartilage associated with their growing ends).

One would need to be concerned with the compression at depth of these structures. However, in principle, as long as cells of the body could get sufficient oxygen and remove carbon dioxide the lungs and other spaces could be compressed without adverse effect, except save pain resulting from deformation of surrounding tisses, such as in the sinuses and at the joints.

The pain from the "bends" comes not from oxygen poisoning, but from the decompression of nitrogen which enters the blood at a stead rate depending upon depth, but which if the blood is sufficiently saturated with nitrogen will bubble out of solution (effervesce) and into gaseous form at lower (near atomospheric) pressures (ie when the diver comes to the surface). The bubbles, which usually appear at the joints, which spaces of compressible gas may be concentrated and deform the joint resulting in significant pain sensed by the nerves of the joint and which typically cause the sufferer to be bent or contorted in an effort to adjust to the considerable pain. Consequently, the "illness" is termed "the bends". It is treated by decompression in a decompression tank, or in the field by sending the diver to decompression depths where they must remain until they vent suffcient nitrogen to safely surface).

The getting "high" effect is the narcotizing property of high concentrations of nitrogen, which can also increase the formation of nitrous oxide (laughing gas), which leads to rapture-like symptoms. It can be induced in a decompression chamber as well.

Mammals. Warm blooded.

[wonkavader]

Warm blooded animals and mammals in general have higher oxygen requirements than fish. Not positive about it, but I think it's a MASSIVE difference.

How much surface area is he going to need? Seems like it's going to be many times that of a fish. But then, that assumes the same efficiency as a fish's gills. Maybe he's far more efficient.

MOD PARENT UP, MOD GP DOWN

[coopex]

The "Anonymous Coward"'s posts seem to vary wildly, from GNAA trolls, to reasoned, insightful, informative posts such as this.

Breathe Under Water Without Oxygen Tanks

[Anonymous Coward]

The real question should be "How long before he sues all the fish in the sea for patent infringement?".

Re:Disagree, think it could find a hold in rec div

[bill_mcgonigle]

You might also be able to generate enough current for it to last alot longer, dynamo, etc.

Brilliant - I was trying to figure out how to get some generation out of the wave motion, but your russian pencil slays my NASA space pen.

Re:Amazing that someone didn't think of this befor

[Anonymous Coward]

I disagree. Inventions come about when someone with sufficient technological knowledge to solve a problem (which may not even be that great) comes forcibly face-to-face with it. When a new technology comes along, it's not really "invention" (and perhaps shouldn't be patentable) when people simply rush in to design the new things that are obviously possible now. True invention, IMHO, always involves putting well-understood technologies together in new ways. Look at Trevor Bayliss and the clockwork radio. There's no technical reason that couldn't have been invented in the 1960s. Conversely, I don't really count one-click ordering as an invention. It was deterministic once the web arrived; the only question was who would think of it first.

THE FRENCH ARE COMING!

[Lotharjade]

Ok, no the french aren't coming...
*looks menacingly in direction of france*

I could swear this technology has been around for quite a while though. In readings of the US navy I could swear I remember that they used a system like this before to breath underwater. It was designed supposedly not just for the unlimited oxygen, but to create a bubble-less system.

You are right!

[MrPower]

gas saturation is directly related to pressure.

Yes you are right but you are forgetting that gas saturation is a function of the pressure of the gas not the liquid.

The only significant supply of air to be dissolved in the sea is in the atmosphere, which is only at 1ATM pressure.

Cool

[iminplaya]

I can finally sleep with the fishies. And wake up the next morning.

This technology is hardly new.

[Anonymous Coward]

Osmotic membrains that do the oxygen/water transfer thing have been around for 50 years. Heck I had a underwater ant colony back in the 60's which my dad got from Edmund Scientific.

There were "problems" trying to get these artificial gill packs to work for human divers then (I believe it had to do the the 32' deep 2 atmosphere limit mentioned ealier, but I was a kid then and didn't care to follow up on the research).

military uses

[CiXeL]

but just think then. if the navy powered it with a small nuclear isotope battery source you could essentially be down there forever.

Re:how long will it take for someone to use this t

[cpt_rhetoric]

Would be interesting to see which is actually more "efficient". I see your point, but what about physiology? I'd assume that underwater your only stroke would be breaststroke or no stroke at all right? Too much drag with any other style. So you're limited to work on your legs. For the human machine, unassisted except for the breathing apparatus, wouldn't the most efficient method be on the surface?

Whoa, wait a sec

[PhraudulentOne]

... This guy is trying to get a REAL patent in the USA? I thought you could only get useless/absurd patents in the USA. Patenting a new system that lets you breathe under water? Puhleeeze. If he patented swimming, THEN I could see him getting the patent, but new technology? Get out of here.

Re: Please explain this..

[Anonymous Coward]

From Comments of the National Association of Patent Practitioners on the Proposed Patent Act of 2005 (Committee Print) May 6, 2005 from here"

g) The resulting incentives would cause practitioners to present overbroad claims in the initial examination phases, to guard client rights to present claims as well as from a sense of self-preservation. This would burden the USPTO, because examiners must examine and enter rejections of claims that otherwise would not have been presented. Moreover, if the examiner did a poor job and did not notice that the claim was overbroad, a patent could mistakenly issue with very broad claims, to the detriment of the public.

I take it, either you are not a patent examiner, or you are a patent examiner who does a poor job..

Re: Please explain this..

[back_pages]

g) The resulting incentives would cause practitioners to present overbroad claims in the initial examination phases, to guard client rights to present claims as well as from a sense of self-preservation. This would burden the USPTO, because examiners must examine and enter rejections of claims that otherwise would not have been presented

An overly broad claim is easy to reject. Think about it for a second. It's easy to find prior art for "an airplane". It's difficult to find prior art for a specific airplane feature. This does not require examiners to enter additional rejections, and that suggestion is, at best, bizarre. Figure out who is making those proposals and whose interests they're protecting. A claim requires 1 rejection. A broad claims requires 1 rejection. Their argument is absurd. Broad claims are merely easier to reject.

Moreover, if the examiner did a poor job and did not notice that the claim was overbroad, a patent could mistakenly issue with very broad claims, to the detriment of the public.

Oh so true. (Sidebar: there is no such thing as an "overbroad patent". The whole notion is silly. You're trying to refer to a patent claim for which prior art exists however a rejection was not made.) Think really hard about a patent claim for which prior art is readily available. Duh. DUR DUR DUH. That patent is worthless because it is trivial to invalidate. You show up in court, you present this readily available prior art, and you go home.

So, about these patent examiners screwing up all the time... How many patents do you hear about being invalidated because prior art was readily available? Present your answer as a percentage of the roughly 70,000 patents issued annually.

I take it, either you are not a patent examiner, or you are a patent examiner who does a poor job..

If I were you, I would start posting anonymously and tossing insults too, because you are clearly out of your element and, like I said 3 posts ago, know next to nothing about how the patent system works. I thought I was pretty polite the first time, but now you're asking to be slapped around a little. Take a hint. I'm more than happy to be informative but belligerent ignorance fails to inspire my helpful side.

Response of the inventor

[Bodner]

I appreciate all the interest and the blogs. Didn't mean to leave you all just hanging there, but it's been a hectic week. I can't respond to each comment individually, but here's the deal in general: 1. There is no doubt that the system will work. Is is as sure as dropping an apple. Simple physics. 2. Many of the skeptical readers are correct regarding use for open system diving. The amount of water required is very large. Assuming a breathing rate of 25 Liters-per-minute (LPM) air (~6 galllons-per-minute) at the surface, and 1.5% of dissolved air means a rate of 1666 LPM of water at the surface, or 5,000 LPM of water at 20 m depth (under ideal conditions). For closed systems, the calc shows 200 LPM of water at all depths. (1 LPM O2 / 0.5%). 3. Unlike fish who 'know' how to extract dissolved O2, this device extracts dissolved air. 4. The contents of dissolved air is slightly different than that in the atmosphere. More like 'Nitrox', and contains 34% O2.

Re: Please explain this..

[Anonymous Coward]

You do realize that you are saying that you understand patents better than the National Association of Patent Practitioners"?

I was merely quoting the portion of their report that refered to "overbroad patents". Something which they declare to be "bad for the public" and you declare "to be silly".

This commitee also expresses the opinion that examiners who do not catch and reject "overbroad patents" are doing a poor job. So, it only follows that if you are a patent examiner who thinks that it's okay to issue overbroad patents because "they don't exist" or "they are trivial to invalidate", then they would consider you to be doing a poor job. Take it up with them, not me.

Further more, since you clearly know these issues better than them, please do them a favor and inform them that they are "clearly out of their element" and that their "arguments are absurd" before they embarress themselves any further.

Addendum

[Creedo]

Forgive me, I missed one thing. You can start the process of becoming an instructor at 60 dives. But it requires 100 to complete. Which can still be accomplished in 6 months easily.

I mean, look at the sort of "specialties" PADI is offering now. Peak Performance Bouyancy? Bouyancy control is one of the cornerstones, perhaps THE cornerstone(given that it emcompasses good breath control as well), of good diving technique. This should be part of the basic openwater certification. A failure in this area leads directly to clumsy, overweighted divers who can and do inflict serious damage to underwater habitats, and are a danger to themselves and others.