Experienced Divers and OOA emergencies

[Jimmer]

I've been involved in an OOA once, and that was due to a massive freeflow at 120 feet. No big deal, just gave my buddy the long hose, did a normal ascent, including 2 safety stops and got out of the water.

 

[scubajcf]

20+ years / over 4000 dives

4 out of air / low on air situations.

2 of them happened in an almost identical scenario. I was on a dive (cattle) boat. My buddy and I were enjoying a dive (had more than 1/2 a tank in both cases). Out of nowhere, someone on the boat who had lost their buddy AND also ran out of air (one was below 60 feet; one was below 80 feet). Donated primary and ascended without incident on my secondary. In both cases, the diver was in an insane panic and I had to calm them down and keep them from bolting - even after donating the air. Ironically, this happened during the same summer .. One of them didn't even thank me. When we got back to the dock, I had some choice words.

1 situation was a buddy who ran out of air / low on air on our safety stop (computer was reading 115psi). He could have ascended without issue (we were in only 15 feet of water). I donated my secondary and we finished our stop and ascended without issue. Absolutely no panic, he was very cognizant of his air status. He had enough to inflate his BC and not a whole lot more.

1 situation was during a decompression dive. Part of three person team. One of the people "ran out of air" during our deco stop. During the stop, we realized said person did not open their isolator valve all the way. We corrected the situation during the stop. No panic - albeit a bit of drama on the boat afterwards between the other two people.

 

[nereas]

Since learning to dive in 1988 I have experienced an OOA emergency twice. Once was my own tank running dry during an ascent from a deep (180 ft.) dive. Another was with an inexperienced diver paniking during a safety stop.

I was wondering if most divers eventually encounter an OOA emergency or if many divers never encounter an OOA emergency even after diving for ten years or more.

Question #1, what were you doing at 180 ft? Dives to this depth are normally planned with twin tanks, or else with a very large single tank and an H-valve together with a stage bottle.

A good diver never runs OOA.

And a diver who runs OOA is not a good diver.

You should always keep your depth shallower than 130 ft, until you take some tech training.

And in the range of 100 ft to 130 ft you should rely on the Rule of Thirds, where you use 1/3 of your total SPG pressure on the outbound leg of your dive, and the second 1/3 to return to the anchor line, saving the last 1/3 as a reserve. Your tank size should be determined to meet this Rule of Thirds, large enough so that 2/3 of it meets your needs for the dive.

Most recreational scuba is done in the range of 50 to 75 ft, and when you venture deeper, you need to plan your dive and your dive gear better.

That is how you prevent an OOA emergency from occuring, for single-tank diving.

And no, I have never run OOA. There is simply no excuse for it, other than amateurish inexperience.

 

[nereas]

3 years, about 600 dives, I've gone OOA once and that was a freeflow we couldn't stop. I was on my buddy's long hose, so it didn't matter, but we should have turned off the tank to stop the noise and prevent me from having to pay to VIP the tank. I have not seen another diver go out of gas.

One of the many examples of the weakness of a single tank.

With twins, shutting off the manifold quickly would have been the appropriate procedure. Even so some tech-ish agencies teach to turn off the tank valve first, which is a no-no. Always isolate first. That way you are not playing russian roulette.

This example is really one of equipment failure rather than simply OOA. Anytime you dive with one-of-everything then you surely need to stay close to your buddy.

 

[dpbishop]

One was a buddy on a 3 man dive, his first dive in several years. He hoovered through his air in record time. Did a buddy-breath ascent with the third guy. Now I visually check my buddies gauge when I hit 2000 psi.

One was me, started a dive with a empty tank that was marked full. (back in the days when they used tape to mark full tanks.) Just never looked at my gauge until I was 80 feet down and sucking aluminum. If you got to do it, do it at the beginning of a dive, no nitrogen loading to worry about. Now I slap a gauge on the tanks before it leaves the fill station.

 

[nereas]

...Out of nowhere, someone on the boat who had lost their buddy AND also ran out of air (one was below 60 feet; one was below 80 feet). ...

This is always my worst nightmare when diving off cattle boats in the open water.

Nice job of handling it well. But of course, that is what would be expected of a scuba instructor! (Dive god.)

 

[GLENFWB]

I have had one OOA experience on about my 7th post certification dive. It was completely my fault, BUT it goes back to the old saying, "When you are new...you don't know what you don't know!" Was watching air very carefully, when we turned to head back, I encountered a stiff current and buoyancy problems....I learned very quickly how SAC rate changes when conditions change...I learned just how quickly a guy like me can suck an AL80 dry. Have never even come close to an OOA since then. It was a lesson I will NEVER forget.

 

[b1gcountry]

No OOA since my third certification dive. We turned into the receding tide to end our dive, and I was about 12lbs overweighted. I couldn't keep up to save my life, and blew through my air trying to keep up with the instructor even after I asked her to slow down.

Since then, I've drained a couple tanks, but that was on purpose.

Tom

 

[Web Monkey]

Since learning to dive in 1988 I have experienced an OOA emergency twice. Once was my own tank running dry during an ascent from a deep (180 ft.) dive. Another was with an inexperienced diver paniking during a safety stop.

7 years and 350+ dives and never had an OOA.

All you need to do is maintain enough gas at all times to take care of all your needs, plus whatever is required to get your buddy or a random stranger safely to the surface at any point in the dive.

This generally means you'll be back on the boat with more gas leftover than you would like, but that's the price of maintaining a safety reserve.

Some people use this to hang out at a safety stop, watch the fish, hang out in the grass, etc., since as you get closer to your exit, you need to maintain less of a reserve.

Terry

 

[fda483]

Over 500 dives and never been OOA. But being a bit of a hoover, usually with a rent - a - buddy, and always with a camera in my hand trying to get that world class shot I always dive with a 19 cuft pony. Never had to use it yet but who knows about the next dive right. By the way next dive will be in Truk in 14 days!!!!

Joe