To shop owners or owners of spare air tanks

[BRT]

Well, good for you.

It is my experience, in diving as well as other pursuits, that emergencies rarely go as well as planned for. I find, as do many, that people react the way they have been trained in emergencies. Therefore it is with a sense of particular purpose that I approach training for and practice of emergency procedures.

Though you don't quite come right out and say it, it sounds like you've practiced a complete ascent on your Spare Air from a depth where that can be accomplished safely, probably no more than 60 feet. Were you able to measure the amount of air remaining at that point? Did you in fact complete the ascent while holding the cylinder assembly only with your teeth?

I'll probably never use a Spare Air simply because my emergency gas planning always includes a one-minute problem-solving time at depth, a three minute safety stop, a one minute surface reserve, and an ascent within the limits baked into the algorithm my dive computer uses. That's enough gas to turn a life-threatening emergency into a mere story, and it still fits into a small package that's easy to carry.

I probably should just practice CESA's. Haven't done one of those for over 30 years. Guess I'll try to make it part way with my Spare Air. Have you been practicing your out of air ascents or are you sure that isn't going to happen to you? I bought a Spare Air when I watched a diver with lots of air run out at 128 when they went head down and their dip tube clogged. If something like that doesn't happen to me I'll probably continue to empty my little tank just before I pack it to return from Mexico. You on the other hand should probably be planning for what happens if suddenly all your planning goes out the window because there just isn't any more air. It happens.

 

[2airishuman]

Have you been practicing your out of air ascents or are you sure that isn't going to happen to you?

I practice out-of-air ascents from depth using a pony since that's the way I dive. I practice CESAs from moderate depths.

I bought a Spare Air when I watched a diver with lots of air run out at 128 when they went head down and their dip tube clogged.

So we now have two first-person reports and one third-person report on Scubaboard of OOAs due to equipment failure.

 

[Coztick]

First time I saw a SA was on Coz. a couple of years ago.
I thought it was a great idea to dive with "extra" air just in case. A few breathes to surface or get to a buddy. I still think they are better than nothing. Instabuddys were not inspiring confidence in my safety.
So I head home with questions. Fortunately for all of us, there is SB. Holy crap, there are a number of people here with very strong opinions backed up by very convincing statements. Literally millions of hrs of BT experience to draw on. Too bad you folks can't agree on much. But wait, that's not bad at all!
Think things through, pick your side. After much deliberation, I ended up choosing a 2 liter pony for vacation diving while using a single in sidemount.
For me, I wanted time to complete a short swimthrough, deploy an smb and make a slow accent with a bit of a safty stop so a 2l is my min.
No CESAs for me in boat traffic. Not even with a few extra breathes but I do realize we all have different levels of comfort...be sure your safe...

 

[EricTheDood]

I still think they are better than nothing.

True, but still a half-assed solution, IMHO.

In the end, it's up to the individual to make his/her own decisions. New divers should make informed decisions, so multiple viewpoints should be presented. My viewpoint is that 3CF is sufficient to get a diver to the surface or close to it, but not enough to make a slow ascent with a safety stop in many situations. Such situations would include deeper dives, or water inhalation that results in coughing at depth.