Breathing directly from a tank at depth

[SparticleBrane]

Okay, are we talking about breathing directly from a the valve or from a regulator in a full malfunctioning free-flow?

I'm curious what the physiological effects would be of breathing a few breaths of air directly from a tank at depth...no regulator at all.

:blinking: :blinking:

 

[monica.kraj]

I have just come back from 2 weeks of diving. As it was a new diving site for me and I went there alone with no buddy, I decided to go diving with a divemaster.

He told me that he once went diving only with the tank and no regulator. I guess it was just for fun,but anyway, this is how he did it: he was holding the tank in front of him. Whenever he needed air, he opened the valved, took some air (but I don't know if it was with his lips around thevalve or not) and then closed it.

 

[Charlie99]

The funniest case of breathing directly from a tank I've seen was during the SI on a boat out of Puerto Vallarta. The Captain, wearing nothing but a swimsuit and a mask, hefted a few of the leftover tanks from our 1st dive, and picked one that had a fair amount of air in it.

Then he hugged the tank and jumped off the boat. Every once in a while there would be a big cloud of bubbles as he opened the valve and took a sip of air. After about 5 minutes he surfaced from his "dive".

Neat party trick.

 

[Doc]

I'm curious what the physiological effects would be of breathing a few breaths of air directly from a tank at depth...no regulator at all.

If done correctly: none.

If not: Over expansion injury, sea water in your mouth, drowning.

Chicks will dig you.

 

[AbyssalPlains]

I'm curious what the physiological effects would be of breathing a few breaths of air directly from a tank at depth...no regulator at all. It seems to me the high pressure air would damage your lungs, but that's about where my knowledge ends. Anyone have a more detailed explanation??

The pressure of the air you'd be breathing would be pretty much the same, with or without reg. There is no way your lips can seal against any pressure higher than ambient pressure. I've seen people sip air directly from a tank and dive that way. It's more a question of skill than a physiological issue. If you were to somehow seal your mouth around a tank valve and crack it open until the air released exceeds ambient pressure your lungs would pop. Whether you were doing this on land or at depth wouldn't matter, provided we're talking any tank pressure that's higher than ambient. I would not try this at home.

 

[spacemanspiff1974]

Years ago, the summer camp that I attended made us stem breathe - and we were just kids. Really nothing to it. You cup your hand over the stem and turn the valve to get enough air. Do not make a seal with the stem.

 

[rockjock3]

I could be wrong, but here is my thought process on this.

As you get deeper you would need to ensure a tighter and tighter seal (from not really needing any seal near the surface) to be able to breath in any of the air. I base this on a simple experiment. Take a hose and try to breathe through it when you are 5 or so feet under the surface and it isn't too hard. Try and breathe through it at 30 feet and you are gonna struggle more. As you go deeper your lungs (an airspace) are compressed and therefore you need more air pressure to overcome the resistance to breathing created by the outside water pressure. This is what your reg does automatically for you.

Doesn't this work the same for trying to breathe from a tank? Wouldn't you need a better seal as you go deeper so that you can build that pressure to a point that it will overcome the outside pressure. I can see doing it under about 40fsw or so (depending on the strength of your lungs, but would it be possible much deeper if you don't get some kind of seal?

 

[Charlie99]

I could be wrong, but here is my thought process on this.

As you get deeper you would need to ensure a tighter and tighter seal (from not really needing any seal near the surface) to be able to breath in any of the air. I base this on a simple experiment. Take a hose and try to breathe through it when you are 5 or so feet under the surface and it isn't too hard. Try and breathe through it at 30 feet and you are gonna struggle more. As you go deeper your lungs (an airspace) are compressed and therefore you need more air pressure to overcome the resistance to breathing created by the outside water pressure. This is what your reg does automatically for you.

Doesn't this work the same for trying to breathe from a tank? Wouldn't you need a better seal as you go deeper so that you can build that pressure to a point that it will overcome the outside pressure.

It isn't like you are trying to suck air from the surface down to your depth/pressure.

Cracking open the tank valve puts a cloud of bubbles into the water. Those bubbles will automatically be at whatever the pressure is at that depth.

Then you capture or divert some of those bubbles over to your face and sip them, the same way you you breathe from a freeflowing reg.

The technique is just as difficult, or easy, at 10' depth as it is at 100' depth.

 

[Doc]

Doesn't this work the same for trying to breathe from a tank?

Nyet. But I did like your reasoning.

Take a hose and try to breathe through it when you are 5 or so feet under the surface and it isn't too hard. Try and breathe through it at 30 feet and you are gonna struggle more.

5 foot depth is really really very hard. 30 feet aint happenin.

 

[rockjock3]

Cool deal. Thanks for the input. I didn't think about the pressure in the bubbles also being increased. Thanks again.