Spare Air on deep but no deco dives??

[Sevenrider860]

I tried to sell my slogan for SpareAir, but I was rejected

“SpareAir: helping divers drown at shallower depths since 1979”

And to think I hoped they’d love it

If we use the old definition of drowning = death...do you have a number of how many deaths have been reported since 1979 using a SpareAir?

I don't use nor encourage the use of a SpareAir, but does anybody really know how many people have died using a SpareAir? There are people that relied on it and survived to talk about it...even with a faster than 10m/sec ascent rate and no safety stop.

 

[reefrat]

Maybe Spare Air needs to provide a “guide to Spare Air use” to explain exactly how it is intended to be used in an OOA situation.
On deeper dives I carry a 13 or 40 bailout but on shallow fun dives I always carry a Spare Air (3) and beleive it is a worthwhile piece of kit.
I cannot EVER imagine simply running out of air- not gonna happen because I ALWAYS know exactly how much I have and am fastidious about managing it so I surface with 500 psi at the very least- usually more. However, a first stage failure due to a blocked valve tube, diaphragm blowout or burst hose is a possibility, albeit remote, so some redundancy is important. My buddy and I have been diving together for more than 10 years and we are pretty good about proximity and communicating so we have the buddy thing pretty much covered.
Spare Air- there seems to be a lot of conjecture about what actually happens if you need one and how Effective it is from whatever depth, in short there is a lot of BS out there.

In an emergency things need to be kept simple and rehearsed, in the case of Spare Air here is my OAA procedure.
Boom or Air stops- grab spare air and take a breath.
Ascertain problem quickly- is my oct working, take another Spare Air breath.
Quick Decision- go to buddy or if not possible go to surface.
If buddy is not an option immediately begin a safe and steady continuous ascent to surface breathing in and exhaling steadily out with neck and airway extended.
Reach surface and exhale into wing- establish bouyancy and then look for boat/downwards for buddy.

There is no hanging around on the bottom for a minute or “safety stops”, everything happens quickly and for that I believe a Spare Air will do the job done to say 80 ft and well within no-deco limits.

 

[BDSC]

I get a kick out of all the "planning" of what folks need if they run out of air at depth. Easy to do sitting at the computer. I know that if I ran out of air at depth, say 90 to 100 feet, I'm not going to be too concerned about a nice slow accent rate or doing a safety stop. A Spare Air is simply a tool designed to give you a few more breaths of air. While I don't have a Spare Air or a pony bottle, I would assume that a SA is much easier to pack and carry on a trip (plane) with you. One of my dive buddies has one and it easily clips to his bc. He's never had to use it but it's there if he ever does.

A SA is not a replacement for a pony bottle. It was never designed to be such. It was designed to be able to give a diver a few more critical breaths of air if that is what is needed to survive. Folks can poo poo them all they want but I suspect they have saved a life or two where the diver would not as likely have been inclined to get a larger pony.

 

[doctormike]

This article proves that a 3 cubic foot Spare Air is enough gas to get a diver to the surface from 100' ..... So once we remove the stupidity from the equation in the linked article, and revisit the final statement in the article: which is "You need 8.5 cubic fee of air" we can subtract the 2 cubic feet calculated for the safety stop and half the remainder due to the faster ascent rate and you get almost exactly the contents of the large model of spare air which is 3 cubic feet. Even if we assume an excessive SAC rate and don't account for releasing the gas slowly to conserve it. 'Nuff said.

Yes. If you (1) do a fast ascent, (2) blow off your safety stop (because there is no reason you should want to do this, especially after a fast ascent), (3) immediately get on the spare air and start your ascent with no delay, confusion, or time to sort out what is happening, and (4) are sure that at no point the regulator loses any gas from your 3000 PSI fill by a brief purge or free flow, you may have ALMOST EXACTLY enough gas to get you to the surface.

Great plan. Because carrying a regular pony bottle is such a huge problem, that you need to do whatever you can to avoid that.

 

[Bob DBF]

A SA is not a replacement for a pony bottle. It was never designed to be such

I believe it was designed to help aircrew to exit aircraft ditched in the water. Finding the SCUBA market was just added revenue.

It's just a tool, and people using a tool should understand its capabilities, and their own.

Dive and let dive

Bob

 

[scubadada]

I dive a 19 cf pony, enough gas for me to make a normal ascent and safety stop from any recreational depth at twice my normal RMV. I have watched the Spare Air discussion on SB over and over. I would never buy and use one, however, nobody would argue that 3 cf is not better than none. I could pretty easily make a direct ascent to the surface from 90 ft, would have to hurry a little bit from 130 feet. This is a lot better than a CESA The main issue is divers not knowing how much gas they may need for a given circumstance and over relying on a potentially inadequate supply.

 

[BDSC]

I believe it was designed to help aircrew to exit aircraft ditched in the water. Finding the SCUBA market was just added revenue.

Bob

I thought the same thing until I looked it up. It's just the opposite. It was designed for the scuba market and started being sold to the military after.

 

[ReadyDiverOne]

Wow I looked away last night and went to dinner with my wife for our anniversary and came back to this amazing discussion!! OK, so thanks everyone very much for all the great input.

I have at least two major takeaways: First, I do agree and think that if I ran out of air at 120 feet or so and couldn't find my buddy or anyone else to grab their octo (I don't dive alone, always in a group), I would NOT be making a controlled ascent and I would NOT be doing a safety stop. I would drop my weights and shoot to the surface as fast as I could, recognizing that I'm likely to get bent. But better bent than DEAD, right? So, as more than a few in this discussion have noted, in that scenario, the Spare Air 3 would be worlds better than nothing, right?

But, second, I've got more than a 100 dives in 2.5 years, all over the Caribbean, and repeatedly in Cozumel and Grand and Little Cayman, and I've never seen anyone with a Spare Air or, for that matter, a pony bottle (as so many have suggested). Yes, I know, 100 plus dives is not that many, but, for example, in Little Cayman I've dived with people with many hundreds of dives (with Reef Divers (excellent excellent outfit, as you probably know)) and no one has ever had a pony or Spare Air.

The issue for me is that I love to go deep, and am usually the deepest one on most dives. My buddy is sometimes 20 feet above me and maybe 20 feet away horizontally, so if a hose burst or an O-ring blew out, etc., I might have to swim hard and fast to him (or another diver). Having said that, I'm in great shape and can swim very fast; I can hold my breath for a long time (yes, I know, I would not hold my breath while ascendiing); and I've invested a lot in very high quality equipment and think the chance of regulator or hose failure is quite remote. Still, I wonder....

I just don't get why I've never seen anyone with either a Spare Air or a pony??

 

[doctormike]

First, I do agree and think that if I ran out of air at 120 feet or so and couldn't find my buddy or anyone else to grab their octo (I don't dive alone, always in a group), I would NOT be making a controlled ascent and I would NOT be doing a safety stop. I would drop my weights and shoot to the surface as fast as I could, recognizing that I'm likely to get bent. But better bent than DEAD, right? So, as more than a few in this discussion have noted, in that scenario, the Spare Air 3 would be worlds better than nothing, right?

Yeah, but think of it this way. The decision to carry a Spare Air, a Pony Bottle or nothing is not a decision you are made when you are about to die. It's a decision that you make ahead of time, when planning your diving and figuring out how you want your gear set up. So I never understood the logic behind "Spare Air is better than nothing". Take the right tool for the job.

It's fine to do diving in relatively shallow, relatively clear water and decide that in the worst case scenario (blown LP hose or unrecoverable free flow), where you find yourself OOG at depth, you are just going to CESA. That's what most people do, which is why you rarely see redundant gas supplies in Caribbean resorts.

If you are diving deep - to the limits of recreational non-deco diving - you might want to protect yourself from injury by carrying something that will let you do your normal, safe ascent even if the worst happens. There is a reason why we don't sprint to the surface and blow off a safety stop, right? Because it's not safe, because you risk DCS. So why would you set yourself up for an injury by carrying a redundant gas supply which will NOT let you do a normal, safe ascent? Of course, if you have NO gas and NO buddy, then a safe ascent is not even an option. But why put yourself in that position if you don't have to?

My 2 PSI.

 

[ReadyDiverOne]

Well said, doctormike, well said indeed. Hard to argue with that.