No air left. Unable to do controlled ascent!

[scubette]

Hi Everyone -
I'm new to this site and well I guess you can say diving as well, of which I just love!

Had a very horrifying experience this past weekend and was wondering if someone could explain to me what to do should this ever happen again.

I was with a group testing out new drysuits for drysuit cert. My buddy and I was swimming toward the back of the group. Well, while diving, my buoyancy was out of control, as some may know, a diver cannot use their BCD for buoyancy control underwater while diving with a drysuit. Low and behold, I was at 47 feet depth with 550 psi left in my tank. I signaled to my instructor and buddy and we started to ascend slowly.

This is what happened next. When I reached 43 feet, all of a sudden all of my air was gone. Within seconds!!! Couldn't believe it. My buddy was approx 7ft below me as I was ascending just above him. I had already exhaled just prior to my air running out and could not inhale any air. There was no air in my BCD. I was stuck, stuck with no air in my lungs to slowly exhale or "aahhh" on the controlled ascent. My airway was closed. Actually, there was no controlled emergency ascent. I kept ascending, was at 32 feet, looked up to the surface and knew I could not make it. I felt like I was going to choke or fight for a last breath from somewhere, but knew it would be water. Didn't know what to do. My gut took over and I made a last ditch effort and swam down about 8ft to my buddy and grabbed his alternate air. I know I wasn't suppose to swim back down, but I had to, to essentially save my own life.

To run out of air is one scary moment, but to run out of air and have NO air in your lungs to exhale to make a controlled emergency ascent is TOTALLY different.

Besides from purchasing a pony bottle or 3cft spare tank, are there other skills or what could I have done when I had absolutely no air left in my lungs to exhale to make an ascent quicker than my buddy was ascending?? Very, very unsettling.

[Wookie]

Ummm. Welcome to Scubaboard. You'll get lots of opinions from divers, here. Please don't think any one is yelling at you, but some of us have pretty strong feelings about this.

First off, of course you can use your BC for buoyancy control while diving a drysuit. You are equipped with many tools to use while diving, the best one is your brain. Inflate your drysuit so it is comfortable, then use your BC to control buoyancy.

Next, if you run out of air at depth, go to where the air is. If it is 7 feet below you in your buddy's mouth, have at it. I'm sure you were taught in open water class not to panic and never hold your breath. Well, those are the only rules to scuba. Everything else is open to interpretation.

I think you did exactly the right thing when confronted with this emergency. After all, you were able to type tonight. I also believe that a completely redundant air source (pony bottle) is a must when diving. Self rescue is the most important skill any instructor can pass on to you. I know it's scary to run out of air. Keep at it, invest in a rescue course, and get that pony.

Again, welcome,
Frank

[Rick Murchison]

Well... you certainly strung together a few good lessons learned here!
1. Know your own consumption rate; monitor your gas supply & head for the surface with enough to make it without having to do a CESA.
2. Stay with your buddy (your buddy must stay with you, too).
3. The idea that you "must" exhale during a CESA is a bit of a red herring - the kicker is to keep the airway open, which it is during both inhalation and exhalation. Attempting to inhale while doing a CESA works just fine... so you could have proceded to the surface - however... as you had air 8' down or 30+' up, I can't fault you for going for the 8' solution - especially since it worked.
4. You absolutely can use your BC with a drysuit.
See #1 again
Rick

[fisheater]

You did VERY well to not panic and decide to get air from your buddy.

I'm quite curious as to why you "suddenly" lost air. Was this rental gear or yours? Has anyone checked the reg and the SPG post dive? Could be as simple as a SPG that reads about 500 psi high, or a reg malfunction.

Was your air turned fully on? If not all the way on, then it may no have delivered air flow at very low pressures.

BTW, there are multiple schools of thought on using the drysuit, BCD or both for buoyancy control.

[Scott L]

Well it wasn't the prettiest of dives but your survival instints pervailed. You will get lots of responses in quick sucession with posters yapping about staying close to your dive partners. In the event of another OOA situation I am sure you will look to their assistance before ascending alone. Sounds like your dive buddy made a quick ascent to follow you and they should be commended. As far as expending air out of your lungs you need only have your airway open to allow expanding air to escape such as blowing bubbles instead of a full blown exhale. I would certainly have your gauge checked for accuracy...

[sea nmf]

The suddenly losing air has me puzzled as well. Could you have been inflating your drysuit accidently, using up air?

Here is what I think. You asked what to do if it happened again. My guess is that it will not happen again, once you figure out why the air you had ran out within 10' of your ascent. That should have been enough air to get you safely up to the surface or to the side of your buddy.

[Rick Murchison]

BTW, there are multiple schools of thought on using the drysuit, BCD or both for buoyancy control.

Here's mine:
The dry suit is for exposure protection. It should be kept inflated only enough to maintain sufficient loft in the underwear to provide that protection.
The BC is for buoyancy compensation/control. It should be used for that.
If you have a BC failure then the dry suit can be used as a backup BC to control buoyancy during an ascent and for flotation on the surface.
Rick

[fppf]

There is a reason they say to be on the surface with at least 500 PSI in your tank, not at 47 feet. Have your gauge checked out and see if it reads correctly.

Even though your lungs where "empty" from 47 feet to the surface the gas left in your lungs will expand by a factor of almost 1.5 times. More than enough expansion to cause Baro trauma.

I also think over all you handled the issue ok. First, don't run out of air. Know that your air consumption rate will increase when your doing new tasks. Stress increases, so does breathing. Second, stay with your buddy, 8 feet is not a lot, until you have no air. You did the correct choice of bolting to your buddy rather then the surface.

I don't think the dry suit played any other role in this other than increasing your stress and air consumption. It is recommended that new dry suit divers only use the suit for control. This reduces task loading, think of doing a CESA and having to vent air from 2 devices. Most experienced dry suit divers at some point start using there BC for control and only put enough air in the suit for warmth. However, this increases task loading when the stuff hits, make sure you can handle it.

[scubette]

Thank you so much for all of your replies. They mean alot to me!! Regarding the drysuit, it was a rental from the manufacturer at their demonstration day. The rest of the gear is mine which was purchased new four months ago. My instructor taught us to use the drysuit for buoyancy control, not the BCD. That's probably why my buoyancy was out of control and used up alot of air. But I do not recall inflating the drysuit once after I saw my air was at 550. I was just shocked and will take y'all's advice to have my SPG checked out as well. My instructor told me 5 times after this happened that I should have went to the surface regardless, never to dive back down. I guess that's why it's still unsettling to me.

[Wookie]

It is recommended that new dry suit divers only use the suit for control. This reduces task loading, think of doing a CESA and having to vent air from 2 devices. Most experienced dry suit divers at some point start using there BC for control and only put enough air in the suit for warmth. However, this increases task loading when the stuff hits, make sure you can handle it.

I don't get this. I would think that a relatively new diver that knows how to use their BC for buoyancy control would be better off using their BC for buoyancy control. I understand that whole task loading thing, but I set my shoulder purge to hold the right amount of air while diving, and the drysuit burps itself on ascent.

I'm not that experienced a drysuit diver, I only have a couple of hundred dives on it, and I'm self taught. What did I miss?