OUT OF AIR - Last ditch effort breath from you BCD

[Amphibious]

He now ALWAYS uses a pony bottle.

so all he did was add more weight and an entaglement hazard. BRILLIANT!

 

[hdtran]

....snip....

That is unless you're as good as the divers in Into the Blue...those guys are good! If you can breathe off a lift bag and pass air mouth to mouth then you can definitely get 10 more minutes of bottom time out of a BC

If Jessica Alba is teaching, sign me up! (esp. the passing air mouth-to-mouth)

 

[dumpsterDiver]

so all he did was add more weight and an entaglement hazard. BRILLIANT!

I never said he was brilliant, but the addition of a 13 cuft pony bottle (carried as a removable sling bottle under his arm) provides redundancy, minimal change in bouyancy and I would argue, an inconsequential additional entanglement hazard.
What's your point????????

 

[Quarrior]

This has been an interesting thread. Here's how I see things.

Experienced diver = Empty BC at depth because they have their bouyancy under control.

New diver = BC full of water at depth. Think back to when you started diving and probably up and including your first 50 or so dives. How much water did you dump out of your BC after diving?

Now, consider this as well, as you head toward the surface you protective suit is going to gain bouyancy, consequently you will not need to kick as hard as you did to begin with. However, you have to remember to exhale so you don't blow a lung out on the way up.

 

[The Chairman]

Please,

People die on rebreathers quite often. Using your BC as a primitive rebreather is senseless! Just keep your regulator in your mouth.

We know that our regulators are designed to deliver air at the ambient pressure. Every atmosphere is 14.7 psi.

An 80 cf tank has a service pressure of 3000 psi. 3000 psi/14.7psi(per atm) gives us about 204 atmospheres in a tank. 80 cf/204atm = 0.392 cf/atm.

Consider that if you run out of air at 99 fsw (4 atm). By the time you rise up to 66 fsw (3 atm) you will have about 0.4 cubic feet of air to breathe. This is about a breath for most people. SOOOOOOO, every atmosphere that you ascend you will have yet another breath from that "empty" tank.

What can we gain from this??? KEEP YOUR REGULATOR IN YOUR MOUTH AS YOU ASCEND FOR SAFE AIR AND NO CONTAMINATES. FORGET THE "Breathe off of your BC" concept as needlessly complicating your emergency ascent.

BTW, I should also point out that you should NEVER, EVER run out of air, or let your buddy run out of air. Don't be OOA (Out Of Air) and OOB (Out Of Buddy) at the same time. OOA + OOB = OOL (Out Of Luck).

 

[Jim Ernst]

id say if that guy is a divemaster then i must be a dive god, he has no dm #, and know dm knowlage to boot, i read most of these posts and i dont know what more to say of it!! he states i am a dm like that makes him an authority on all dive info, wooow scary!!!lol i am a dm, and man i do have a lot more to learn!!! lol

 

[HowDidIGetIntoThis?]

If you have a good breath in your lungs you sure can exhale the whole way up.

I haven't run into this situation in the real world and there is this nagging question at the back of my mind - what's the likelihood of having a lung-full of air at the time that I discover an air supply problem? Seems to me it is more likely to be discovered after I've exhaled and am trying to draw in more air.

 

[Starboard Tack]

It was stated earlier, but it may be buried in the bunch. When your tank starts to get low, it becomes more difficult to draw in a breath. While uncomfortable, you will have about 4-5 normal breaths left depending on how you breath. Time to head up.

 

[miketsp]

Huh? Moving air from the BC to the lungs or lungs to the BC will not change buoyancy at all so I'm not sure where you were going with that.
..snip..

Breathing out and into the BC is not actually a bad idea if you can do it calmly.
You have to breathe out and this would be lost buoyancy.
It will improve your buoyancy because as you rise the air in your BC will expand and help you rise faster and then give you additional support at the surface where you may arrive almost unconscious and gasping for breath until you recover.
I would not want to breathe from the BC.

 

[Web Monkey]

Don't get me started on that one.

"Oops I ran out of air! How did that happen?" is about as dumb as "Oops I'm pregnant! How did that happen?" It's not like we lack the technology to determine what's left in a tank. People who come up with no air drive me crazy, not only because they were seconds from death (OOA divers typically don't keep very good track of their buddy either), but because they usually think it's funny.

I was on a boat once where they added a significant charge to clean and VIP the tank if it came back with less than 300 PSI, and included it right in the dive briefing: "Be back on the boat with 500 PSI. If you come back with less than 300 PSI, we're going to charge you for cleaning and inspecting the tank."

Terry

BTW, I should also point out that you should NEVER, EVER run out of air, or let your buddy run out of air. Don't be OOA (Out Of Air) and OOB (Out Of Buddy) at the same time. OOA + OOB = OOL (Out Of Luck).