PerroneFord
Contributor
Mandy3206:PerroneFord, I've to respecfully disagre with some of your coments:
1)The ponybottle, SA, H2O concept is not superfluous, when murphy strikes, it's
allways when you can get boned, so self rescue is the best approach to everything in life. It's better to ascend calmly than to rush to the surface in an emergency ascent, just make sure you don't dive to 130ft with a SA and think that it will save you, if you do, just be aware and prepare yourself mentaly for the last leg of the ascent will be an emergency ascent.
If you're going to 130ft, get the apropiate redundant air source, it all comes down to using the right equipment for the dive and not exceed those limits.
2) 80cf last me 60 min in less than 35 fsw, but I rarely dive that shallow, I dive most of my dives between 65 fsw and 110 fsw with an average dive duration from 25 min and 45 min depending on the dive profile.
3) A bail out bottle is allways a good idea, no matter if you dive by the book and never exceed your limits, as for buddies, I personally don't rely on a buddy to help me out, if he can help, good, but I don't rely on them to save my life.
All fair counterpoint. Murphy is a son-of-a-gun!

1. Again, if you are dropping down to 130ft, NDL is about 10 minutes on air. I don't think most recreational divers will be traveling down that far for a 10 minute stay. So either they will let it go, or they will be into mandatory deco. A scary proposition without redundant gas.
2. Again, I was probing at basic recreational depths. At 50 feet, you've got 80 minutes before mandatory deco. So unless you've got a more than 80cuft on your back, you shouldn't be running out of air. And if you're calculating your profiles to leave a healthy reserve, you shouldn't be anywhere NEAR running out of air. Not saying recreational users should be turning on thirds, but beginning the ascent with 1000 psi probably isn't a bad idea. If you're pushing the limits (90ft+), I'd be looking for more strict planning.
3. I will respectfully disagree that a bail-out bottle is "always" a good idea. But your point is well taken. Proper gas management, in whatever it's form, is a good idea for all divers. And the idea of redundancy isn't only the domain of technical divers.
To my mind, diving with a team mentality is important. Yes, you should be self-sufficient, but either you have a team, or you are a solo diver. There really isn't anything inbetween.