For years I’ve heard of Spare Air, but just had never had the opportunity to purchase one or try it out. I queried a number of my instructor and diving friends to get their take on this product and found that none of them had used it, most were indifferent about it, and more than one of them had some unkind things to say about the mere idea of it. I found this intriguing, and while I understand to some extent where their ire comes from, I don’t agree with it. I will cover their concerns here, because their concerns actually mirror my own. However, where they and I differ is that they feel ‘no good diver should use that’, and I feel that every good diver should have multiple backups to help save their lives should the SHTF. (just think about it, you’ll get the initialism)
What is Spare Air?
If you are unfamiliar with what Spare Air is, it’s a small bailout bottle. The one I tested holds 3 cubic feet of air at 3000 psi and has its own on demand regulator. This is a small bottle that is intended to be kept on your person while diving just in case everything goes wrong and you run out of air. The main thing to understand here is that you should never run out of air. If you do run out of air, then you or your equipment really screwed up. Either way, this small bottle is intended to help you abort your dive and get to the surface alive. That is all it is intended to do: save your life if everything else has gone wrong.
These are the specifications for the model I used, the largest of their two models:Maximum Capacity: 3.0 cu ft / 85 litersLength: 13.4" / 34 cm
Diameter: 2.25" / 5.71 cm
Maximum Pressure: 3000 psi / 200 bar
Weight (full): 2.17 lb. / .985 kg
Surface Breaths (est) : 57
Water Volume: 26.62 cu in / .42 liters
The Spare Air cylinder is filled with a scuba tank, and to get it full you’d need a tank that has 3000 psi in it. Filling it was quite simple. There’s an adapter that screws into the Spare Air cylinder and then attaches to the scuba tank just like a first stage. You then slowly open the scuba tank and let it fill until the pin pressure indicator is flush with its surroundings. When you’re done filling, you close the scuba tank and then release the pressure in the first stage by turning an easily recognizable pressure release valve. I did notice some air leaking the first time I tried to fill it, but a quick look at the instructions indicated that I merely needed to check the pressure release valve on the Spare Air and tighten it.
Attaching to the BCD
The cylinder comes in a holster that easily be attached to a BCD in many different ways, depending on your setup. A velcro top keeps the cylinder secure in the holster and makes removing it quite simple and easy. For added security, there is a leash that hooks the cylinder and holster together so that if you drop the cylinder once you’ve removed it from the holster in an emergency, you won’t actually lose it.
There are two clips on the holster for attaching to a BCD, and these clips can be moved up and down the holster itself, and adjusted smaller or larger in diameter for a perfect fit. However, this is where I had issues with my setup. The instructions show you three common-sense ways to attach the Spare Air to your BCD, but none of them really worked with my setup straight “out of the box”, so to speak. I was able to get it attached for my testing, but not in a manner that I would use recreationally going forward. I am confident that with some ingenuity I will be able to get it attached in a manner that I am comfortable with as well as still being easy to get to. And, I don’t imagine that this extra strap or band that I will buy will cost all that much. What’s important is that it’s out of the way but still accessible, and this could take a little trial and error depending on your personal setup and preferences.
Caveats to my breath testing
During all of my tests, a couple of things need to be understood. First, I wasn’t under stress while during these tests. That means my breathing rate was ‘normal’. Second is that I do have a large lung capacity and my breaths were large, deliberate, and deep breaths and not short shallow ones. Last is that I started filling the bottle with a tank that had 3000 psi in it. But with each fill, the pressure in my fill tank dropped, which means that each test I ran I actually had a little less air in the Spare Air cylinder. I’m estimating that on the surface I had the closest to 3000 psi. At 60 feet, I had more like 2800, and at 30 feet, I had closer to 2600.
Surface / 30 ft / 60 ft Breathing Tests
I started out my testing by filling the cylinder and breathing it empty on the surface. That took me approximately 48 breaths, versus their purported 57 breaths. Of course, their estimation is just that - an estimation. I did take deep breaths and as I mentioned, I do have a large lung capacity.
I refilled the cylinder from the same scuba tank, which meant that it wasn’t quite full for the next test. Possibly it was around 2800 psi or so. I dropped to 60 feet and started breathing and timing. Immediately I was shocked at how difficult it was to breathe off of. Obviously, it was a drastic difference between my balanced reg and the one on the cylinder. Once I got over that initial shock, however, I adjusted my breathing and it was just fine. I just wasn’t expecting the tightness of the reg and it surprised me. It took me roughly a minute and a half to breathe it out, give or take a few seconds, and I took about 22 breaths off of it. More than enough air to ascend from 60 feet with ease.
Next refill probably put the cylinder at around 2600, where I then dropped to 30-ish feet and started the breathing and timing again. I was able to sit there and breathe off of it for over 2 and a half minutes and took about 37 breaths. Once more, clearly enough air to ascend with.
Unfortunately, I haven’t had the opportunity to test it out any deeper than that yet, but I plan to.
- Easy to fill
- Functional holster
- Secure leash
- Brightly colored
- Small and lightweight
- Enough air to surface from most recreational depths
- Easy to remove from holster
- Always on, on-demand regulator
- Can take some work to get it attached to your rig the way you want it
- Regulator breathes hard, especially in deeper water
- Can be hands free, but better to hold in one hand
- May not have enough air to surface with from deeper depths
Fact of the matter is extra breaths are better than no breaths, no matter what the reasons for needing them. This is a piece of gear you buy with the hopes of never, ever having to use it. Kind of like air bags on a car, reserve parachutes, or maybe that handgun in your purse, they’re there if you absolutely need them but they are last ditch efforts to save your life when something else went horribly wrong. No one should ever buy Spare Air and get lax in any of their other diving habits due to thinking, “It’s okay if I run out of air, because I have extra.” No no no no NO. It’s not “okay” if you get into a car accident just because you have an airbag. Likewise, it’s not “okay” to become lax in your dive skills and habits because you have a backup plan. Let me stress one final time: You should not ever need this. If you do, then you really screwed up. We are all human though, and we are known to make mistakes. This bailout bottle could possibly help you with one of those possible mistakes.
I will recommend the following things for anyone who plans to purchase or maybe even already has purchased a Spare Air cylinder. Practice with it. Mess with the setup underwater and find the best location on your gear for the holster. Find a place to put it that’s out of the way but easy to get to. Once you do, then practice pulling the bottle from the holster quickly. Do it over and over, so that if the need ever arises, you already have that muscle memory. Next, breathe off of it underwater so you know how the regulator breathes and it’s not a shock to you in an already stressful situation.
Once I figure out the best way to hook this to my rig, I will be diving with the Spare Air recreationally from here on out. While I hope that I will never, ever have to use it for any reason, I’ll feel happier knowing it’s there …. just in case.