Using Nitrox...

[MaxBottomtime]

As to point (ii). I am confused as to the statement. If one on gasses less N at a given depth are they not less exposed to DCS? Am I missing something?

There has been no reduction in the number of reported DCS cases since the introduction of nitrox for recreational diving. Theoretically, it may offer a smaller risk, but in reality it hasn't proven to be safer.

 

[Charlie99]

Those aren't the effect im debating. The 2 things i take issue with are much touted and neither has a single objective/reviewed evidence to back it up. Those are the claims:
(i) less fatigue post dive and
(ii) diving nitrox on air tables reduces the risk of DCS

Ive yet to see ANY evidence to support either claim.

I've never seen any evidence that a 60'/18m dive for 30 minutes has less DCS risk than a dive to 60'/18m for 50 minutes either. But I'm willing to extrapolate from what is known and bet that there is indeed lower DCS risk for a dive has less nitrogen loading.

Same thing for a nitrox dive. Less nitrogen loading, therefore less DCS risk.

Now the AMOUNT of DCS risk reduction is open to debate, and whether or not that reduction in DCS risk is important is a very subjective, personal decision.

 

[String]

Trying to fit theoretical benefits into real life physical creatures doesn't always work out the way you'd think. If it did, medicine would be years ahead of where it is now.

 

[BlueDevil]

Hey!! Don't knock it. It works for religion for some.

Don't even get me started on that pile of crap

Hey careful guys! I got a 3 day suspension from Scuba Board for making a comment that a moderator felt challenged his religious sensibilities. With Australia being one of the least religious countries in the world we are pretty free to be as critical as we like, but it seems that is not the case on ScubaBoard!

 

[BlueDevil]

This has been a very interesting discussion with some good information being considered. As far as the NDL issue and extension of dives goes it is really quite depth dependent. The benefits of nitrox in this regard are probably at their greatest in roughly the 25 -35m range. After 35m the benefit diminshes until at around 40m and onwards the mix you are using is going to be so lean that it will carry little benefit at all. For example a Nitrox 28 mix will only give you an extra 3 mins at 40m so from my perspective that small benefit doesn't outweigh the negatives (extra cost, increased ox tox risk etc). For dives approaching 40m you are better to just use nitrox as a deco gas, that would provide much more benefit. However for rectangular profile dives around the 30m mark the benefit can be substantial.

 

[String]

Hey careful guys! I got a 3 day suspension from Scuba Board for making a comment that a moderator felt challenged his religious sensibilities. With Australia being one of the least religious countries in the world we are pretty free to be as critical as we like, but it seems that is not the case on ScubaBoard!

Id agree with that. Free/critical speech isn't tolerated in certain areas which is a shame. And this will probably get removed for being off topic

 

[DaleC]

I finally understand some others viewpoints on the subject (had to sleep on it). We have had that very discussion in real life regarding the fact that air diving is already safe enough so adding safer doesn't "really" make it safer. I think that for the most part one can say that is true (though there are other reasons for using EAN) but I wouldn't go so far as to say it is theoretical. I would say it is negligeble because the saftey factor does still exist.
I could say the same thing about my automobile seatbelt. I am a safe driver, never had an accident, so my seatbelt offers safety within an already safe environment. Is it theoretical safety..negligeble.. real? Either way I still wear one.

I think all the other points have been covered so there is no point in my rehashing them - a good discussion by all

 

[Katamuki]

I for one firmly believe that Nitrox makes me very much less tired at the end of the day. I boat dive from 4 to 6 times a week all year long and go through 3 bottles of 32 per day and can tell a HUGE difference from when I used to do that all on air. Diving with that frequency non-stop and also mixing in several night dives a week and the "tired" benefits are very tangible, at least for me. Most of the average dives are past 20 meters with some approaching 30 meters if the customer wants to see something in particular. I do keep a steel 100 on board for my use if the dive is planned past 30+ meters though.

 

[Blackwood]

(ii) diving nitrox on air tables reduces the risk of DCS

Ive yet to see ANY evidence to support [that] claim.

Do you really need evidence to believe it?

Consider the opposite. Is there data about diving air on Nitrox tables?
(probably not)
Without that data, would you discount the statement "diving air on nitrox tables increases the risk of DCS?"

 

[halocline]

As ha But also, a better regulator will help - like the Scubapro Mk25 first stage, coupled to an S600 second stage (which is what I was advised to purchase). This requires less vacuum (suck!) to get the air to deliver (the S600 is adjustable while diving). This makes breathing from a tank a lot more like breathing on the surface, and hence enables lower air consumption at depth.

Bravo to the shop that used that sales pitch to get you to buy an expensive reg. I guess even the old faithful "isn't your life worth it?" line needs a break now and then.

Your top-of-the-line SP reg is very nice and will serve you well for as long as you want it, but it will not lower air consumption. What do you think, less expensive regs are like sucking molasses through a straw?