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#622
Spare air
Matt65 - 10/31/2008 2:02 AM
Category: Equipment
Replies: 8

I’m curious to hear from anyone who might have actually used a spare air. I have one, and never have used it. I have often thought about just trying it out on a dive ascent, just to see if in a real world test done by myself, how it would work from depth, say from 60 feet or so. Has anyone actually used one? Either in a real out of air situation or just to try it out? If you have, how was it? Did it work out for you? Was there enough air to do a safe ascent with safty stop, or was it more like just enough air to do something more like an emergency ascent? Thank you for reading my forum post, take care and dive safe!
#481
Aqua_Nut_Angel - 10/31/2008 9:23 AM
I dive with a full 19 cubic feet pony bottle and think is one of the best dive investments I’ve made. I conducted a 10’ pool dive and a 60’ spring dive test and found it’t plenty of air for any recreational dive I make within DECO limits. I find experience divers tend to think they’re close to each other, especially when the water is clear, but they’re not. Next time you dive test how long it takes you to get to your buddy on a breath of air...it’s a wake up call. I’m a pony bottle believer. See my Oriskany pic..you’ll see the bottle..I make the rigs for this type bottle.
#2225
DiveNClimb - 10/31/2008 11:24 AM
My buddy bought one last year so on one of our dives we stopped at 45 feet and he went to his spare air. He is good with his boyancy and his air consumption. Staying still and relaxing he got 21 breaths from it. It is an emergancy only device. Hope this helps. Joe
#3933
seawolfdiving - 10/31/2008 12:08 PM
I have a spare air that I usually like to take with me on dives that are no deeper than 60 ft. Sort of an"extra insurance policy".

I carry an 19cuft pony or larger on any dive that is deeper than 60ft.
#5919
SCUBASMITTY - 11/01/2008 11:34 PM
LIKE THE OLD SAYING GOES, ITS BETTER TO HAVE IT AND NOT NEED IT, THEN TO NEED IT AND NOT HAVE IT!!-GUN’S CONDOMS OR AIR,,, THE THREE MOST IMPORTANT THINGS THAT COME TO MIND!! - I NEVER DIVE WITHOUT A SUIT,ON BOTH ACCOUNTS, I ALWAYS CARRY MY 30 PONY AND MY SPARE AIR WHENEVER I DIVE, I AM A FORMER SMOKER, MY LUNGS NEED AIR WITHIN ONE MINUTE, I TRYED TO FREE DIVE TO 14FT TO GET A MOARING BALL AND COULD NOT DO IT!!-I HAVE COME UP FROM 125FT ON A SMALL SPARE AIR BUT COULD NOT HAVE DONE SO WITH A DECO STOP..PLEASE,PLEASE,PLEASE,,GET ONE!!!
#506
steelheadfish - 11/02/2008 5:34 PM
well i guess out of this group my 30cu is a bit big but matches in lenth to my 85cu steels. i feel that the 30 is my min for dives to 100 feet
#1887
MDW - 11/03/2008 2:44 PM
My thought is that a "Spare Air" unit is too small to be really useful. A "real" pony bottle (12, 19, or 30 cu ft) and low end regulator are about the same cost as a "Spare Air" and provide 4 to 10 times the air reserve as the "large" (3 cu ft) "Spare Air" and about 7 to 15 times the air of the small (1.7 cu ft) "Spare Air" unit.

That said, I have 2 observations regarding your situation.

1. This would have been a good question to ask before you bought the "Spare Air"

2. Since you already have a "Spare Air" you are better off with it than without it. (i.e. better to have a little reserve than none)


Let’s compare ponies. Assume a "stressed" SAC rate of 1.0 cu ft / min (after all you did just run out of air, so you are probably a bit stressed).

Spare Air 1.7 - 1 min at 15 ft (short safety stop)

Spare Air 3.0 - 1 min at 30 ft or 2 min at 15 ft.

AL 19 - 30 ft/min ascent from 120 ft to 30 ft (3 min) and 1 min stop at 30 ft, and 5 min safety stop at 15 ft. (light deco)

AL 30 - 30 ft/min ascent from 130 ft to 100 ft, and 1 min deco at 100 ft, and 30 ft/min ascent to 70 ft, and 1 min deco stop at 70 ft, and 1 min at 60 ft and 1 min at 50 ft, and 1 min at 40 ft, and 1 min at 30 ft, and up to 3 min at 15 ft. (adequate deco)
#326
diverjmacj - 11/05/2008 9:13 AM
Various reviews of spare air suggest it is marginal at best for shallow dives, 30 ft +_. You need to know your breathing rate to evaluate what works best for you. I use a 13 cf pony which gives me time from over 100 ft to make a safe assent with a safety stop and still have a little air left at the surface if I have bad surface conditions. The pony provides a full back-up to my primary reg. I use this configuration when solo diving or spear fishing with friends because I cannot trust them to stay close. I remove it when diving with my wife, students, etc.
#355
firediver57 - 11/10/2008 4:15 PM
I tried it once to see how many breaths I would get out of it if I need it. I mostly keep it with my fire department turn outs in case I need to get to a submerged car quick. I can get between 35 and 45 breaths on it depending on exertion. I used it once to check a submerged car and fortunately everyone had been thrown out. I normally carry a 40cu ft pony bottle on my recreational diving and had a freeflow on a rental regulator that a buddy used and jammed the pony reg in his mouth. It works fine. I also screwed up once and didn’t monitor my air close enough and used the pony to finish a safety stop.