Spare Air- good for diving or not?

[RJP]

No practical use in Scuba whatsoever.

C'mon... what other piece of scuba gear lets you run out of air twice on the same dive?

 

[Michael Guerrero]

ORRRRRRRRRRRRRRRRRRRRR!!! You could just watch your gas and never put yourself in that kind of situation. Follow the rule of 1/3's and you should never have a problem. 1/3 in 1/3 out 1/3 reserve for emergency. Plan your dive and dive your plan!

Until the o-ring on your tank valve fails, or your first stage fails, or the crappy burst disk that hasn't been changed in 15 years fails, or...

 

[Vegan Shark]

Until the o-ring on your tank valve fails, or your first stage fails, or the crappy burst disk that hasn't been changed in 15 years fails, or...

Wouldn't these failures lead to a freeflow, though? You can breathe off a freeflow while doing an emergency ascent.

 

[JohnN]

Spare air is good for snorkeling, . . . .

Great idea. Lets take someone with no training and give them compressed air at depth. What could possibly go wrong ??

 

[Divetech99]

Where would you attach a spare air in a DIR setup assuming right hip has canister, left hip has D-ring and knife? On the backplate secured by bungee on the backplate holes?

 

[redacted]

C'mon... what other piece of scuba gear lets you run out of air twice on the same dive?

Still better than not making it back to the surface.

---------- Post added December 2nd, 2014 at 09:24 PM ----------

Spare air is good for snorkeling, AL-30 is my option and is about the same amount of money with a lot of more air A LOT MORE.

Works fine for "local" diving.

 

[Michael Guerrero]

Wouldn't these failures lead to a freeflow, though? You can breathe off a freeflow while doing an emergency ascent.

If your burst disc fails or your valve o-ring fails (the thing that seals the valve to the tank) it doesn't result in a free flow, it results in a jettisoning of air into the surrounding water at a very high rate (you might get a minute if you're at the start of your dive). And depending on the failure of the 1st stage, same thing.

---------- Post added December 2nd, 2014 at 09:37 PM ----------

Where would you attach a spare air in a DIR setup assuming right hip has canister, left hip has D-ring and knife? On the backplate secured by bungee on the backplate holes?

You wouldn't attach a spare air in a DIR setup.

 

[ajduplessis]

There is nothing wrong with contingency planning and utilizing redundant systems while diving. However the use of spare air and the general application thereof is what is troubling IMO. Firstly the capacity is to small especially for inexperienced divers. Secondly it creates complacency wrt situational awareness and training (buddy system/safety drills). I don’t know of any diver worth his salt that uses spare air……enough said.

Spare Air only exist because of marketing and the large % of divers that don’t trust their skills capability (or never acquired them during training) and should not be diving in the first place.

This poll and further discussion around spare air is useless. The only reason many of the experienced divers on the forum elected to contribute is to hopefully discourage newer divers from going down this route and rather focus on quality training and doing things right in the first place.

Spare Air will kill you in the long run, because that is what complacency breeds.

 

[Max Speed]

Wouldn't these failures lead to a freeflow, though? You can breathe off a freeflow while doing an emergency ascent.

Or your dip tube clogs...

---------- Post added December 3rd, 2014 at 01:19 AM ----------

This poll and further discussion around spare air is useless. The only reason many of the experienced divers on the forum elected to contribute is to hopefully discourage newer divers from going down this route and rather focus on quality training and doing things right in the first place.

Spare Air will kill you in the long run, because that is what complacency breeds.

Because someone (like me) might disagree with you?

 

[ajduplessis]

Your dip tube clogs up ... WTF???? From what, your lunch? Go and buy more spare air, you really are going to need it.