Gill Envy
Contributor
surely for many folks, that is the way to go, it's at least simpler. However, there are a lot of misconceptions, even with doubles the NDL/deco obligations rack up so much faster than they do on a rebreather in moderate depths and the fills for doubles are, well, twice as expensive... and you have to put up with the effects of all that additional nitrogen every step of the way, from the descent where the po2 is lower than it has to be, to the ascent where off gassing is much slower because you can't increase the fraction of OC nitrox as increased oxygen tolerance with shallower depths would allow.
I found that the MOD restrictions of nitrox get old fast, if you ran independent doubles with two gas mixes then you could get a taste of what a rebreather can do for you... although you'd have to predict how deep you'll want to go and when to make the switch etc, etc. I don't plan my dive and dive my plan, I plan for a max depth and dive within that range adjusting the plan according to conditions, my deco computer and what I find of interest on the fly. diving nitrox can be pretty dissappointing if you get close to the MOD and see something a little deeper than the MOD allows. Ask just about any nitrox diver and they can come up with times when they would have given their eye teeth to go a little deeper to check out that eagle ray or some other cool critter. a rebreather gives you a lot of freedom if you are willing to make the initial investment. Comparing continuous gas blending to swing po2 diving, you begin to realize how amazing it is to increase the o2 fraction on your down and on your way up. a lot of the Nitrogen that would linger in your system on OC nitrox gets flushed out before you get to the surface, significantly reducing the "nitrogen fatigue" many of us experience.
Aside from the initial ivestement, it's not necessarily cheaper to dive nitrox. My experience is that per hour, diving a rebreather is actually cheaper than diving nitrox. It's complicated, it's not for everyone, but I do believe there are a lot of avid sport divers who can benefit from the advantages of rebreather diving... and I do believe that that is just a matter of time.
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