wirelessguru1 Wrote:
-------------------------------------------------------
> > As a PADI Rescue Diver might I ask what
> happens if the diver has to drop his weights?
>
> The Diagram on the article showed a small
> emergency air supply chamber! I am sure that all
> the secondary emergency systems will also be
> properly designed...
>

Yes and thats all well and good and many divers carry these pony-bottles (as they are called) as standard practice now (I can't afford one ) but these bottles are only for emergency use, and if your in an emergency enough to have to drop your weight belt or weight shots you probably wouldn't have either a) the time, or b) the composure to switch breathing methods manually

> > The other thing that concerns me about this
> is how much air can this extract feasibly?
>
> I am sure that he is testing that!
>

I'm sure he is going to test it, and as I indicated at the end of my post it is an exciting prospect. However, as a diver I'm just pointing out the bits that make me go... erm!

> > As you get deeper in the water due to the
> pressure of the water the amount of air contained
>
> > in a lung full is far more than at the
> surface.
>
> Please explain me this? It seems to me that
> "pressure" would reduce lung capacity!!!
>

no the air gets denser (thicker) as the presure of the water compresses it. Heres a good practicle experiment for you to try WG. Take a clean empty pop bottle to your local public swimming pool. Go to the entry ladder in the deep end and take the top off. Hold the bottle upside-down and push yourself just a couple of meters under the water. Now assuming that you can either a) see underwater or b) are wearing goggles, you will see that without leaking any air the water will be now well inside the bottle. The air has compressed at the depth.

> > So at 10meters you use twice as much air as
> you did at the surface, at twenty meters you
> > use twice as much as you did at 10 meters.
>
> Where did you get this air-usage "formula" from?
> Do you have a link to that?
>

As I said to Stephen in a lower post I will double check this (it is what we were taught) and will post the rational and links

> > So as a conventional diver gets deeper the
> less time their aqualung will provide them
> > with air. So in a nutshell… how deep could
> you go before the device could no longer
> > keep with demand?
>
> Again, where did you get this from? From your PADI
> Rescue Diver instruction manuals?
> What the article was saying is that by lowering
> the pressure you can recover more air, so the
> "reverse", which is to increase pressure, you
> would recover less air! So, if (1) one's air
> needs do indeed increase with the pressure and (2)
> by going deeper it increases pressure and,
> therefore, less air can be recovered, you would
> have these two key issues working against his
> invention!!!
>
> eom
>

yes my manuals. But consider this... at the depth, and at the pressure its going to take a lot more energy to reduce the pressure to extract the gas and thats assuming the system can take an increase in pressure like that. Sorry but I'm always cautious when it comes to putting my life in the hands of any complex system... the more it does... the more it can go wrong. Thats one of the reasons I'm OK with the aqualung... you fill a cyclinder with air then you breathe it (OK thats over simplified but you take my meaning).

As I said in my original post. Its an exciting interesting technology... but as a diver I never hold my breath!

Mike