Gas Switching

Hey everyone,
Im looking into getting a computer, and I want one that I can change my gas mixes while diving, for example making a deep dive on air and then deco-ing on nitrox or O2. I know the diverite nitek duo and nitek plus can do so, and im looking at the nitek plus. I was just wondering if anyone had any other suggestions for me to look into.
Thanks

I like the dive rite computers. I currently use the nitek 7 or (nitek HE) as also known.
i've tryed a few of the others like the Air X, and Z, and the cobra, vitek i like the dive rites the best.

There is also the Cochran and VR3 computers. Or you could use tables and/or v-planner.

The Smart Tec allows you to use up to 3 mixes.

I'd ask your adv nitrox/deco procedures instructor what he/she recommends.

Rachel

I use a uwatec smartec and a vr3... just to have redundancy.

The uwatec does 3 gasses and keeps track of remaining bottom time. The vr3 does like... 32 gasses or so on 3 different profiles.... and plays deco games.

I have used a suunto vytec for several years now and love it. Having said that my diving has progressed well beyond it's abilities and now I generally use it as an expensive bottom time. If you have taken deco training you will probably find you will not need it.

If you are slinging deco bottles you should be on trimix for the deep stuff, not air. A multigas nitrox computer isn't really what you'll want except as a very expensive bottom timer in gauge mode.

I use a TUSA IQ-700 and a Dive Rite NiTek3. TUSA doesn't have an equivalent to the DR NiTek Plus. Be careful about buying a NiTek Duo or Apeks Quantum model as there was some production that evidently had problems.

Oh yeah, the TUSA IQ-700 comes with a 2 year warranty vs. the DR 1 year, and there's some flexibility on pricing.

You should consider giving Larry at Scubatoys a call in any event.

And, you can see the models of dive computer this outfit recommends, for a point of reference. Hit the "Dive Equipment and Skills Needed to Dive Bikini" link. They used to recommend the DR NiTek3 before that model was phased out and replaced by the DR NiTek He in Dive Rite's production.

http://www.bikiniatoll.com/fabioletter.html

See the DR NiTek Duo is recommended as the 'upgraded version' - i.e. non-buggy I suppose since there hasn't been any public notice for what exactly is / was causing problems with that model and the Apeks Quantum.

Personally, we'd probably venture next to rebreathers in our training progression instead of going to trimix on open circuit, but to each his own.

StSomewhere:

If you are slinging deco bottles you should be on trimix for the deep stuff, not air. A multigas nitrox computer isn't really what you'll want except as a very expensive bottom timer in gauge mode.

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I do dives to 150 ft on air on aregular basis. I also do about 130-150 dives per year. If I dove with trimix on every dive below 100 ft, I would be diving a lot less. There's room for deep air.

As for using deco bottles, even on a deep air dive, accellerated deco will cut your deco in half or allow you a higher degree of safety. And if a diver does go the trimix route it makes a lot more sense to do it with a ton of experience in accellerated deco and in using deco bottles prior to getting into a trimix course than it does to go in cold.

diveAK:

Hey everyone,
Im looking into getting a computer, and I want one that I can change my gas mixes while diving, for example making a deep dive on air and then deco-ing on nitrox or O2. I know the diverite nitek duo and nitek plus can do so, and im looking at the nitek plus. I was just wondering if anyone had any other suggestions for me to look into.
Thanks

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There is a big difference in cash between a gas switchable air/nitrox computer and a computer capable of helium mixes so I understand the attraction.

My concern with any computer is that it can fail and murpy's law dictates that it will fail at the worst possible moment. Consequently, I never rely on a compter as anything more than a back up bottom timer. If you are doing intentional deco, the gas and deco planning cannot be short cutted and that is all too easy for many divers to do with a computer.

You need to know more than just what amount of deco you need to do with what gases, you need to know that you have enough gas along for any of the possible contingencies. Consequently, the gas planning still has to be done and that still requires the development of a deco schedule and contingencies before you get in the water. Consequently, it makes a lot more sense to then take the primary deco plan as well as contingency plans for extended bottom times and loss of one or more deco mixes and put them on slate. The computer should only serve as a back up to your primary bottom timer and depth gauge and the only purpose it may be useful for in anything other than gauge mode is getting you to the surface sooner if you abort a dive mid way through.

So in short, I'd think twice about investing in an expensive gas switchable computer - if you get far enough into open circuit deco procedures to know what you are doing, do it well and do it safely, you'll have gotten to the point where you are not using it as a computer anyway.