Why extra air when solo?

[TheGraveyardDiver]

I carry a 13 cu ft strapped to my main.

1) it weights just a few pounds out of the water, so "hurting my back" isn't an issue.
2) In the water it weighs next to nothing. The Aluminum 13 didn't affect my buoyancy one bit. I used 14 lbs before and I use 14 lbs with it strapped onto my main.

"In all my years I've never seen..." isn't a valid defense to not having redundant air. I have a spare tire on my truck but I've never had to use it. I also have a fire extinguisher on my boat that I've never needed. I have a concealed handgun permit and a pistol but I've never had to shoot anybody. Also have O2 on the boat but never needed to use it. Never needed the air bags on my truck either.

Prior experience isn't an indicator of future need.

I've never needed to switch to my pony in a real situation, but my practice shows me I can surface from 100 feet at a safe rate, do a short safety stop, and return to the boat with about 300 PSI left if I needed to. If I never need it, that's fine with me. It's cheap insurance.

 

[Diver-Drex]

SM here. Prior to that I used a pony. Redundant gas is the standard on NJ dive boats, solo or not.

I’m agnostic as to an octo or not on the backgas if you have a pony. But I don’t agree with swapping it back and forth. You introduce a greater chance of o-ring failure than just leaving the octo attached.

 

[Satrekker]

Ok, I’ll bite. What’s the point of solo diving with a fully redundant gas supply and then putting two second stages on your back gas?

I don't disagree. I'm just too lazy to take my necklace off the 1st stage and put in a plug. :-O

 

[Eric Sedletzky]

The idea is not so much more gas as a separate supply in case the first one becomes unavailable.

In cold conditions a freeflow is a likely event. If you are at all deep and on your own that is a proper problem. A freeflow is just one example, other failures are possible and you don’t want it to be a death sentence.

+1

 

[Satrekker]

OK, so clearly the thing to do is to wash out my BC with vodka before diving so there are no microbes in there, and then if there's trouble while diving, breath in and out of the BC if there's nothing coming out of the regs. Which ought to work for a few breaths, and the vodka fumes may improve the experience. Seeing as an alternate air source could kill me, and all.

(For members for whom English is not their first language, this is a stab at humor.)

Don't laugh. When I was first certified in 1984, I was taught to use my Seaquest bcd bladder as an emergency air source.

 

[pauldw]

Don't laugh. When I was first certified in 1984, I was taught to use my Seaquest bcd bladder as an emergency air source.

Yeah, the Royal Life Saving Society Canada produced a book by Albert Pierce in 1985 that was interesting for the number of things it had in it that you'd never see in a PADI manual. Apparently they don't water things down in the Great White North. Five pages of different techniques related to breathing off a BC. Perhaps they tested it on the McKenzie Brothers first, whose blood alcohol probably purged the bladders of any pathogens.

 

[John C. Ratliff]

KenGordon said: ↑
The idea is not so much more gas as a separate supply in case the first one becomes unavailable.

In cold conditions a freeflow is a likely event. If you are at all deep and on your own that is a proper problem. A freeflow is just one example, other failures are possible and you don’t want it to be a death sentence.

+1

Ken,

If you are diving in that cold water, and a freeflow is "Likely" with your regulator, you may wish to look at different regulators which have a much lower likelihood of a free flow problem. There are regulators evaluated for use in the Antarctic Ocean, and a new double hose regulator, the Argonaunt Kracken, which are much less likely to free flow due to their design keeping water away from the second stage.

SeaRat

 

[happy-diver]

https://www.amazon.com/Scuba-Life-S.../ref=tmm_pap_swatch_0?_encoding=UTF8&qid=&sr=

wonder if it has a savage dog filter

 

[KenGordon]

Ken,

If you are diving in that cold water, and a freeflow is "Likely" with your regulator, you may wish to look at different regulators which have a much lower likelihood of a free flow problem. There are regulators evaluated for use in the Antarctic Ocean, and a new double hose regulator, the Argonaunt Kracken, which are much less likely to free flow due to their design keeping water away from the second stage.

SeaRat

“A freeflow is just one example, other failures are possible and you don’t want it to be a death sentence.”

Freeflows will happen, usually first stage freeflows, no matter what OC kit is used, expanding gas gets cold and freezes stuff. People do actually die this way, a member of another local club died about three years ago due to a freeflow. It is not if but when.

Really a lot of what we teach people is about redundancy. Initially that comes from a buddy, eventually from kit and a buddy, and then for solo just from kit. I don’t expect kit to fail, it almost never happens, but freeflows are common.

Personally I use Apeks regulators. I think they are excellent and very suitable for deep cold water, however I wouldn’t bet my life on taking just one on a dive.

 

[Storker]

Freeflows will happen,

Absolutely, but:

usually first stage freeflows

I've seen a fair amount of 2nd stage freeflows. I've had a few myself. Nearly all of my clubmates who dive during winter has had one or more. All of them on the surface, nearly all of them after the dive.

I've yet to experience, see, or hear one of my clubmates tell me about, a 1st stage freeflow.

What are we doing wrong up here since our experience is directly opposite to what you're saying?

PS: We agree 100%, though, that it's a very good idea to have a fully redundant gas source if you're diving solo or can't make a direct ascent at any time during the dive