Why no poor man's rebreather?

[ronski101]

Why has not someone invented a cheap, safe, easy to use semi-rebreathing system?
Since we only use 4% of the 21% O2 available in a breath from an open circuit tank, why is there not a system that would allow us to rebreath that first breath twice before expelling it thus allowing double bottom times or much smaller air tanks? Is it that difficult to scrub that one breath of CO2? Does that one breath really have to be scrubbed? If you start with Nitrox you should have about 30% O2 in the first exhaled breath to play with and only have to deal with CO2. Even if you could only save half of that first breath it could be a great advantage in diving with less bubbles, smaller tanks, longer bottom times, less dry mouth, deeper with nitrox, etc. Scuba has been around 60-70 years and has changed very little in the basic system.
This may have already been answered but I have not found it on this forum.
Don't flame me to bad......

 

[ShakaZulu]

What if your breath smells

http://www.youtube.com/watch?v=eBp1xfbFD5k

 

[Rhone Man]

Once rebreather use reaches critical mass, I am sure the prices will start to tumble steadily.

 

[Jim Lapenta]

Poseidon has one that is geared to the new diver. As in you do your OW training with it. Don;t know the cost or if it's really a good idea. But if I had the opportunity to get one at a reasonable price, that is reliable and would allow me to do the dives I normally do for fun, I'd buy one. But it is still 6K complete plus training.

 

[sea2summit]

Why has not someone invented a cheap, safe, easy to use semi-rebreathing system?
Since we only use 4% of the 21% O2 available in a breath from an open circuit tank, why is there not a system that would allow us to rebreath that first breath twice before expelling it thus allowing double bottom times or much smaller air tanks? Is it that difficult to scrub that one breath of CO2? Does that one breath really have to be scrubbed? If you start with Nitrox you should have about 30% O2 in the first exhaled breath to play with and only have to deal with CO2. Even if you could only save half of that first breath it could be a great advantage in diving with less bubbles, smaller tanks, longer bottom times, less dry mouth, deeper with nitrox, etc. Scuba has been around 60-70 years and has changed very little in the basic system.
This may have already been answered but I have not found it on this forum.
Don't flame me to bad......

Semi closed allow you to do that sort of. Remember 4%x2 from the 21% puts you realy hypoxic and ready to have the walls close in on your brain...not a good time.

Check out a used drager or some such on ebay, usually you can find an operational one for $800ish which is far less than most BC/reg set ups would cost you.

Beyond that, rebreathers are just a machine that is waiting for an opportunity to kill you, unless you have the prefect machine like scubadad, when you are least expecting it. That really is the reason it will never be "easy".

 

[Thalassamania]

Here it is, cheaper than just a tank:

A $100 HOT WATER BOTTLE PENDULUM REBREATHER

 

[300bar]

Here it is, cheaper than just a tank:

A $100 HOT WATER BOTTLE PENDULUM REBREATHER

I'd rather dive with a Spare air.

 

[sea2summit]

I'd rather dive with a Spare air.

Why? O2 RB's are where it's at for less than 20' depth. His was more complex than most I've seen.

 

[Thalassamania]

Reminds me a lot of the Pirelli I first trained on. I think I'm gonna build two.

 

[herman]

I'd rather dive with a Spare air.

You may not feel that way if you knew who that is. He is a well know rebreather expert and designer with a bunch of patents to prove it. Real nice guy to and yes that is a working rebreather.