Out of Air Emergencies - what are the principal causes?

[dc4bs]

Oops,

I should have made clear. He doesn't bring it when he's training his own students... He brings it when doing deeper recreational dives (70-130 fsw) and he doesn't know all the other divers going. If anyone asks, he just tells them its how he normaly carries a pony.

 

[coliseum]

Well, I had a 16 Littre Tank... My Buddy was on a standard 12L...

I always ensure I check mine... however he did not check his as we were preoccupied with getting a cage out of the water (with a SMB)...

He ran out (thank god I had a 16L).... I believe we were at 39M depth... anyways... we did an Alternate Air Source Ascent with the cage and the SMB...

No harm was done and I came up with around 90or 100 BAR still in the tank... even after doing a Safety stop for 5 Minutes (always extra safe)

 

[MXGratefulDiver]

Bonnet Ray once bubbled...
I am currently thinking of taking my nitrox speciality as that may improve my consumption.

Actually, breathing nitrox will not improve your gas consumption ... although it does offer other advantages. The reason is that although you will be breathing in more oxygen with each breath, you will still be generating the same amount of CO2 ... and it is the CO2 that triggers your breathing response.

The major advantages to nitrox are that it ...

- reduces your risk of DCS, due to a lower nitrogen intake (less tissue saturation than air at the same depth/time profile)
- allows you more bottom-time than air at comparable depth
- reduces fatigue caused by nitrogen loading ... particularly on multiple dive days

But that's all another topic ... getting back to this one, you'll still empty your tank just as quickly, whether you're using air or nitrox.

... Bob (Grateful Diver)

 

[MXGratefulDiver]

I've been involved in two OOA's and several near OOA's ... and it's always been due to operator error. However, those errors can be broken down into some different categories ...

- The dependent diver, following a buddy who is either more efficient or has a larger tank ... this is usually a situation where the OOA diver either failed to notify the buddy of a low air situation, or the buddy chose to ignore it thinking "I've got plenty of air for both of us."

- The new diver, who is so task loaded they simply forgot to look at the gauge until the regulator stopped delivering air.

- The careless diver who thinks it's OK to routinely suck the tank down to 100 psi on every dive. It always amazes me how many "experienced" divers do this.

We recently had a diver death in our area due to an OOA. This kid went to 93 fsw on a tank he'd already done one dive on ... then separated from his buddy on the way up.

... Bob (Grateful Diver)

 

[chaseman24]

While I was doing my second day of OW certification dives, I had a very near OOA situation.

We had done a few skills and were basically touring around, and being that this was only my 3rd or 4th OW dive, I was sucking down air like crazy. So, I informed our instructor at the agreed upon pressure mark (can't remember what it was, something like 1000 psi I think) and he signaled ok, and continued the tour. I thought, "no big deal, he is aware of the situation". Now I'm keeping an eye on my gauge and I am a going lower fast, and getting a bit more nervous, so I show him my gauge. Once again, I get an ok and we continue on. Finally, my gauge is getting REALLY low, thankfully my wife (and buddy) was well aware and keeping right by my side. Our instructor gives the signal for our ascent and my wife is ready to provide air if need be (I wish I could remember the psi at this point). We finally reached the surface and I pressed the inflator button...and nothing happened, not even enough air to inflate my BC. So, I orally inflated it.

After the dive, I was bugging my instructor about it and he jokingly said, "Well, at least you got your money's worth out of the air in that tank!"

 

[tiswango]

"I use more air than my buddy" question is quite simple - use a larger tank.

If they're diving 80's, go out with a 95 or 100. Or etc.

-----
I disagree, before you start buying bigger tanks, you need to get more dive experience.

New diver's have horrible SAC rates because of a host of reasons. If you can get 50-70 dives in you will realize you can exhale your breath and not need as much weight. When you take weight off you don't need as much air in your BC. Less weight and air in the BC means you can have trim. Once you master trim, you move through the water efficiently.

Efficiency equals less air consuption. Less consumption means less chance of running out in the first place and more diving enjoyment.

--Matt Hoelscher
Ft. Laurderdale

 

[beaker]

And it didn't happen to me, but I've seen enough second stages freeflow down to an OOA in the winter time.

Some might say its a mechanical problem. I disagree - a perfectly good regulator can do this...

This is one where its hard to place blame on the operator... in which case treating the symtoms is the best thing to do at that moment, as treating the cause (not diving in the wintertime / cold) isn't something some people will do....


-mike

 

[The Chairman]

that %99 of all diving accidents (where there is an injury) are diver induced and less than %1 are equipment malfunctions. If you realize that properly working equipment (even rented junk) is the diver's responsibility, we are getting closer to %100 diver error.

Unfortunately, we seem to spend %99 of our money on gear and only that last %1 on training. We have more confidence in our gear pulling us out of a bad situation than our heads. Not good!

Diver stress is the #1 factor for an OOA. Over tasked, or under trained divers lose their focus way too easily and their air is gone without them ever realizing it. Dive instructors as a whole seem to under-stress gas management or problem management in their classes, leaving us with hordes of divers who have never given much thought to prevention or UW problem solving. In fact, many instructors spend more time on the "solution" (an ESA, etc) then they do on the prevention. Still, an instructor letting a student run out of air is simply unconscionable! As a friend preacher would often say "Brethren, this ought not to be!" The instructor should not just be a "safety net"... they need to be the redundant set of eyes on EVERYONE'S gauges. I have yet to have a student finish a dive with less than 500psi. -I- plan to keep it that way.

As for following DMs... divers need to understand what a "trust me" dive is and avoid them! YOU should plan your OWN dive, and then dive it as YOU see fit, and that includes a gas mangement plan that keeps you safe. Do not relegate your life to anyone else! That's just farm animal stupid! If you don't know how to handle a particular dive, then CALL IT! Dive within your training and abilities. There is nothing under the water worth giving up your life to see. Really! Get the training FIRST, and then do the dive if and only it matches your abilities.

 

[ericg98]

Was once in a group where I saw a guy run out of o2 cause he was too busy taking pics than to look at his spg, lucky for him his dive partner was nearby, which was not the usual case for them. , needless to say he was lucky, depite the fact that they shot right to the surface. A good lesson for all.
E

 

[NAM001]

i had one instance where the j-valve rod was pulled. though low air had a contrled assent. a buddy blew to the serface. thank god j-valves are gone.