Redundant air supply source

[DC53]

I am a recently OW certified diver, new to the sport and have a question about redundant air sources. My plan for quite some time is to stick shallow water recreational diving, although eventually dives that approach the no-deco limits could be on the horizon (no rush.) I tend to be methodical about equipment and in general like the idea of having redundancy, but being methodical and careful enough to end up not having needed it. I donÃÕ like the idea, however, of dragging around a 30 cu ft pony bottle both out of water and underwater on a sling, for a 30-50 foot dive. I would be happy to hear what ever people have to say about this subject, but also want to get opinions as to whether the 3 cu ft Spare Air is a legitimate redundant air source for shallow water recreational diving.

PS, the issue of cost is completely not important on this for me. For the sake of discussion think of alternative air sources (if recommended) as ÅÇree? That is, I donÃÕ want to know ÅØhat I can get by with at this time but instead, ÅØhat is the ideal equipment with these parameters? Thanks for any input.

 

[tc]

Welcome to the board DC53!

I presently use a 19CF for nearly all of my diving, I'll switch out to a 30 only if I'm going to be working deep.

The 3 CF units are pretty small, if you do a calculation of your air consumption (and remember- if you're in a situation that requires your redundant supply you'll probably already be breathing pretty hard) you'll see that it probably wouldn't allow for any kind of safety stop- just enough to (hopefully) get you through an emergency ascent.

Here's a link to a post I did a while back on the differences between a 13 and 19CF tanks-

http://www.scubaboard.com/forums/3896053-post7.html

 

[rjack321]

The general consensus is that 3cf is rediculously small and you are likely to just run out of gas twice. At 60ft for a stressed out of gas diver, 3cf is roughly 2 or 3 breaths. They should stop marketing those things to divers and stay in the ditched aircraft business.

In addition to the possibility of a 30 or 40cf pony bottle that you mentioned, there's always your buddy. And last resort is a emergency swimming ascent. All 3 (the pony, the buddy, and the CESA) are more attractive to me than any of the spare airs.

 

[elan]

I am a recently OW certified diver, new to the sport and have a question about redundant air sources. My plan for quite some time is to stick shallow water recreational diving, although eventually dives that approach the no-deco limits could be on the horizon (no rush.) I tend to be methodical about equipment and in general like the idea of having redundancy, but being methodical and careful enough to end up not having needed it. I donÃÕ like the idea, however, of dragging around a 30 cu ft pony bottle both out of water and underwater on a sling, for a 30-50 foot dive. I would be happy to hear what ever people have to say about this subject, but also want to get opinions as to whether the 3 cu ft Spare Air is a legitimate redundant air source for shallow water recreational diving.

PS, the issue of cost is completely not important on this for me. For the sake of discussion think of alternative air sources (if recommended) as ÅÇree? That is, I donÃÕ want to know ÅØhat I can get by with at this time but instead, ÅØhat is the ideal equipment with these parameters? Thanks for any input.

What is the temperature of the water are you going to dive ?

If you dive cold water you better get a pony of an appropriate size.

 

[Jorgy]

From my perspective.......

13 CF is the absolute minimum.....

19 CF is what I use ............which I sling........

30 or 40 CF is the way to go if you decide to go technical...........

Lots of good info on SB related to this........

M

 

[Peter Guy]

I'll bite -- in most classes your "redundant air source" in recreational diving is your buddy which is why learning "buddiness" is such a good skill. As my friend says, you and your buddy should "dive to stay found" so that if/when you have an issue, the buddy is there to do their job.

Don't worry about what kind of pony you should have -- worry about becoming and having a buddy who can be your redundant brain AND air source.

 

[scarefaceDM]

« Peter Guy beat me to it. »

Consider this...the best redundancy..is a good buddy.

It is funny how newly certified divers look toward getting another air source when typically you have one when diving with a good buddy. « I did this when I first started also»

I am not picking. I am pointing out something that is all too common. Ask yourself why you need a redundant air source. Look at the typical dives you do. what environment etc..that calls for a redundant gas supply. Are you diving overhead environments, penetrating a wreck going into a cave etc...This typically calls for more gear and advance training. Which at this stage of the game in a non issue. But further down the road a consideration.

Since you are newly certified. I would for one, concentrate on mastering your skills. Buoyancy is a common problem we all face. Mastering this vital skill will help greatly in your SAC rate. Making you more efficient in the water and thus lessening the call for a redundant air source.( you will suck back less and be less stressed)

If you stick to shallow depths, a redundant gas supply is not needed. If you are bordering the NDL limits then consider a bigger tank aside from the typical alu80. Master your skills before adding a redundant air source. Regardless if it is a 3 Cub or a 40 cub. Once you have hit this stage in your diving...look at how and where you want to go. Typically those that carry the redundant gas...do not need it.

There is no replacement for a good buddy.

 

[DC53]

What is the temperature of the water are you going to dive ?

If you dive cold water you better get a pony of an appropriate size.

Generally warm. There's a thermocline in the quarry nearby and I understand that at bottom of the deep part it can be 47 degrees but I've no intention of going there right away. My regulator is environmentally sealed.

 

[boulderjohn]

Altough for the kind of diving you are describing it is safer to have some kind of a pony, the overwhelming majority of divers believe they are safe enough with a buddy and a reasonably quick trip to the surface in a worst case scenario. What do I mean by overwhelming majority? I have seen thousands of divers in many resort diving areas (see my profile), and I don't think I have seen 5 pony bottles being used in all. (Yes, I have seen a handful of those silly tiny bottles, which do not count in my view.)

Part of the reason for that is travel--most people don't want to go to the trouble of bringing one on a plane, and if a typical resort operator offers them for rent, I don't know about it. If you are routinely diving locally, it may make more sense.

 

[Doc Intrepid]

"I am a recently OW certified diver, new to the sport and have a question about redundant air sources."

As a brand new certified OW diver, now would not be the optimal time to add more equipment and associated task loading to your dive profiles.

Redundant air sources are a topic that has been and will continue to be argued, and there really is no one correct answer.

But whether they are ultimately necessary or not necessary, most will agree that they are simply additional expense, additional weight, and additional task loading for brand new divers.

This is because brand new divers have lots and lots of other skills, equipment, and procedures to become familiar with, indeed to become extremely proficient with...and new divers will best be served by moving incrementally towards more complex diving.

Why not consider spending some time diving, possibly take a rescue course, get some experience in areas like buddy diving, peak proficient bouyancy, Advanced Nitrox, UW communication, UW navigation, extended range, O2 and First Aid, and increase your experience in the field. You will find that as you do these things your equipment list will grow and you'll have more and more task loading that you'll incorporate into your dives.

Somewhere in there you'll add sling tanks, Surface Marker Bouys, spools/reels and line handling (scuba floats, etc.), possibly cameras, and other equipment - but I recommend that of all those things adding a pony bottle is something that you push off until a bit later, rather than making it one of the first ancillary pieces of equipment that you purchase.

Just my humble opinion. Your mileage may vary...

Doc