To Nitrox or not to Nitrox: that is the question

[boulderjohn]

Actually you are quoting articles that reference the DAN research, not the DAN articles themselves right? I just don't want to put words in DAN's mouth here, not trying to be picky.

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Actually, you are right--forgot where I was when I quoted it.

I am indeed a DAN member (in reference to an earlier post you made), and I am still looking for the article that everyone seems to think they posted. I found a number of articles that DAN wrote in reference to Nitrox, most of which deal with oxygen toxicity. I can't find anything that says what people in this thread seem to be saying it says. I could still use some directin to tha article.

 

[in_cavediver]

Increased safety is a benefit, but insignificant statistically unless you are that one guy more out of 10,000 that the study showed took the hit and maybe he was a knuckle head. Being in better shape, hydration, proper sleep, slower ascents, safety stops, common sense, diving within limits...these are the things that the DAN research says will play a more significant role in decreasing DCS hits. I think the nitrox class and others should focus more on these things instead of claiming a HUGE margin of safety just because one is using nitrox, as some shops do. "Get your geezer gas here!" "Be a safer diver!" ""Feel less tired, use Nitrox!" I have seen all of this written on LDS windows. That isn't a very clear and honest message to send. Nitrox is only a tool to decrease bottom time, the rest is icing on the cake, but hey, icing is better than no icing I guess.

Here is where I disagree with you. Nitrox has many benefits depending on *HOW* its used.

1) It can be used to extend bottom times
2) It can be used to reduce surfaces intervals
3) It can be used to aid repetive dive options
4) It can be used to reduce inert gas loadings

All of these are benefits but only one has a basis for reducing risk of DCS.

I take all of the DAN 'studies' whoever wrote them, with a grain of salt. The raw numbers they quote are for all uses of nitrox. Methods 1, 2, and 3 are means to extend the time required to hit a specific inert gas load, not to lower that gas load, which means they have NO DCS reducing impact.

My opinion is that most recreational nitrox divers use nitrox to do one of the first three benefits. There is a small group who are already at elevated DCS risk who use nitrox (#4) to try to mitigate other risk factors (and the upshot is, this mitigation may bring thier risk in line with a normal diver diving air!).

All in all, DCS risk, when diving properly, is very small and diving nitrox in air limits while providing some measure of benefit, is likely not significant for your average diver following the best practices. Its only when other factors - pushing limits, sawtooth profiles, and other inherent elevated DCS risks come into play that this benefit would be realized in a meaningful way for a diver.

 

[scubadobadoo]

Here is where I disagree with you....

...All in all, DCS risk, when diving properly, is very small and diving nitrox in air limits while providing some measure of benefit, is likely not significant for your average diver following the best practices. Its only when other factors - pushing limits, sawtooth profiles, and other inherent elevated DCS risks come into play that this benefit would be realized in a meaningful way for a diver.

How do we disagree? You have summed up perfectly what I have already stated.:huh:

 

[CoyKoi]

Scubadobadoo did a nice job cutting through the confusion by posting the links to those 3 articles. I just finished rereading the ScubaDiving Magazine article and appreciated the facts-versus-fiction discussion.

I almost always dive Nitrox under the following conditions:
1. Repetitive dives over several days when max depth on each dive is below 50'. (Nitrox profile, to maximize bottom time)

2. Any dive over about 60' where I want to maximize my bottom time AND where the water temp isn't too cool to make me cut the dive short. When I pay $$$ to take a 3-hour bumpy boatride out to the U-352 off Morehead City, NC, I want every minute of bottom time I can squeeze out of my dive. (Nitrox profile)

3. When working as a DM at our local lake I'm up and down all day with students, so I'll dive Nitrox on an air profile.

I've never felt any reduction in normal after-dive fatigue from Nitrox, but my 56-yr old husband swears he does. Hey, if the placebo effect keeps him happy as my dive buddy, I'm just as happy to go along and agree with him. As always, regardless of the enthusiastic advice you get from your fellow divers on SB, take the Nitrox course, read the articles Scubadoadoo refered to and then decide for yourself. Have fun and dive safely.

 

[in_cavediver]

How do we disagree? You have summed up perfectly what I have already stated.:huh:

Actually, I thought I did disagree and spent a bit of time going over it. Then, I re-read your post and my reply and realized, hey, we do agree. Since I spent the time typing a reply, I felt obligated to post it....

 

[Carribeandiver]

Dude,

Take the class .... Get the knowledge, then dive it or not.

Shark out.

Seems like the best advice yet. After long and careful consideration, that is exactly my plan. Take the course because it will offer more academic knowledge about diving. Then I can decide if I want to use it or not.
Thanks Everyone, I sincerely appreciate the input.

 

[Crawl79]

Caribbean Diver sounds like a good idea for everyone. I did the same thing and as stated before for diving the Flower Gardens its great.