How much air to surface with?

[RJP]

What if you breathe it "dry" while you're at 30 feet, then descend to 90 feet (presumably, breathing off a different tank/pony), for some reason?

How do you come up with this sort of nonsense?

 

[archer1960]

How do you come up with this sort of nonsense?

Let it go; he's just coming up with "what if..." scenarios. It doesn't mean him or anybody else would actually do this.

 

[stuartv]

Let it go; he's just coming up with "what if..." scenarios. It doesn't mean him or anybody else would actually do this.

Seriously. Saying that there is NO WAY a person could have an empty tank and then have water pressure force water in is nonsense... I didn't say it was likely. Nor did I say anything about hitting a purge button. I was just responding to a statement that seemed to be factually incorrect (which is nothing to do with how likely it is).

 

[ev780]

Seriously. Saying that there is NO WAY a person could have an empty tank and then have water pressure force water in is nonsense... I didn't say it was likely. Nor did I say anything about hitting a purge button. I was just responding to a statement that seemed to be factually incorrect (which is nothing to do with how likely it is).

I stand by my "nonsense!"

 

[RJP]

Saying that there is NO WAY a person could have an empty tank and then have water pressure force water in is nonsense...

No one said that. Your jump from a criticism of your example to the complete opposite position is telling.

The problem is that the scenario in your example is so ludicrous as to preclude continuing the conversation in any meaningful way. DD's "kittens have invaded my gas tank" scenario is only slightly less likely to occur, with such margin of difference being explained by the obvious sarcasm.

The "nonsense" aspect of your scenario underscores one of two things (or perhaps both) that seem to get you in all of these tussles:

• an innate desire to always take up an eristic position, no matter the discussion
• a lack of real-world practical experience

Those are pretty much the only two things that could possibly explain a diver coming up with a scenario wherein a diver breathes their tank to dry and then "for some reason" not only continues their dive, but actually descends from 30ft to 90ft.

 

[stuartv]

No one said that.

Oh. Then I must have really misinterpreted this:

I think the water in the tank thing is an urban legend! I can't for one second believe that any human can breathe a tank dry enough through SCUBA equipment to get a tank to zero or negative pressure which is what is required to get water into a tank through that little hole in the valve!

 

[Dhboner]

Now Stuart...just when we were starting to get along there you go again arguing for arguing's sake.

 

[NAM001]

Stewart

I haven't read all the posts but i will say that what you purpose could happen could happen. The problem with your supposition is that for it to happen may other things would also have to happen. like the reg fell off and left the valve exposed open and out of air when you went deeper. This just doesn't happen. The only practical ways to get water in a tank is when filling and not doing it with a dry valve and the whip blowing the water into the tank. The other way is a bad (maintained) compressor system or improperly run system (moisture drains not used) that is blowing water into the tank. I have seen one other time when water went into a tank and that was moisture separators plumbed backwards where the compressor air came in the top and was taken our of the bottom (should be reverse). That watered and rusted my new lp95's up quickly.

There are some crazy things that we all have seen. For instance,,,,, I have watched in hind site a diver make the plunge and find they for got to put their regs on. Did that get water in the tank. no the valve was shut. It would have been impossible to be open cause to open the valve it would have been obvious that there was no reg on the tank (air blasting). now the tank (rental) could have been MT but chances are that it would have had some air 2-500 in it to alert the diver that the reg was not on.

 

[scagrotto]

Oh. Then I must have really misinterpreted this:

You did, and it's because you've got a problem with comprehension (or an inability to grasp reality). What you quoted was prompted by the discussion about whether or not breathing a tank dry will result in getting water in the tank, and is therefore based on the implicit assumption that the diver isn't going to follow that up by doing something wildly ridiculous and implausible. Maybe if you reread the thread you'll be better able to follow the context.

Another case in point:

What part of "breathing off a different tank/pony" means that someone drowned?

Awap simply offered a hypothetical (and unlikely but realistic) example of a situation in which a diver going OOA would warrant a VIP, and pointed out the real reasons that tanks get water in them.

 

[doctormike]

...an innate desire to always take up an eristic position, no matter the discussion

This one post taught me more than the other 138 in this thread.

I googled "eristic", and now I have learned a new word.

Thank you!