New to Nitrox - Do I need to buy an O2 Analyzer?

[Diver0001]

I'm a very new diver. I completed OW last month. I'm just now completing my Nitrox Certification. I plan to dive mostly on vacations to the warmer waters.

The questions is: Do I need I need to buy an O2 analyzer or will most dive resorts or live-aboard operators have one that I can use. I expect to be able to dive 2-3 weeks a year.

Thanks in advance for your advice.

Personally I always test twice. The first test is to ask what they THOUGHT they put in the tank and then to check it with the shop's meter. The second test is to test with my own meter. I suspect that it should be enough to ask the technician what they thought they did and to test it once to verify. Testing twice I've never seen it vary beyond the tolerances of the meters.... that said... it only takes once.

As for "owning" a meter.... I don't think you need to necessarily "own" one but you should have access to one.

R..

 

[RJP]

As for why a new diver would go straight to nitrox, I'm 71 years old and my MD recommend I use nitrox to avoid fatigue on multiple dives.

Ah, yes. That ol' chestnut again! Is your MD a dive physician?

If not, have him read this DAN article on whether there is any scientific evidence that Nitrox can reduce post-dive fatigue:
(Executive Summary: No)
Alert Diver | Air, Nitrox and Fatigue

Or this article on whether Nitrox can reduce post-dive fatigue:
(Executive Summary: No)
Harris RJ, Doolette DJ, Wilkinson DC, Williams DJ (2003). "Measurement of fatigue following 18 msw dry chamber dives breathing air or enriched air nitrox".Undersea and Hyperbaric Medicine (Undersea and Hyperbaric Medical Society) 30 (4): 285–91.

Or this article on whether Nitrox can reduce post-dive fatigue:
(Executive Summary: No)
Chapman SD, Plato PA. "Measurement of Fatigue following 18 msw Open Water Dives Breathing Air or EAN36.". In: Brueggeman P, Pollock NW, eds. Diving for Science 2008. Proceedings of the American Academy of Underwater Sciences 27th Symposium.

Or this textbook chapter on whether Nitrox can reduce post-dive fatigue:
(Executive Summary: No)
Brubakk, A. O.; T. S. Neuman (2003). Bennett and Elliott's physiology and medicine of diving, 5th Rev ed. United States: Saunders Ltd. p. 800

He can then compare those findings to this study which shows some effect... but ultimately concludes "These involve complex phenomena in the functional modifications of the nervous system in hyperbaric environments according to the type of gas used for the dive, and more research will be required to elucidate them."
Evaluation of critical flicker fusion frequency and perceived fatig... - PubMed - NCBI

Or you can have him abandon any sense of evidence-based medicine and just read all the posts on ScubaBoard wherein anonymous strangers claim that Nitrox does in fact reduce post-dive fatigue based on their personal "n=1" anecdotes.

Here's how I understand it from looking at the research, from speaking with dive physicians, from reading the anecdotes on ScubaBoard, and from crewing on dive boat, working as an active PADI Pro, and just from seeing 1,000s of divers and dives while traveling all over the world...

1. The typical recreational diver has sloppy dive skills and techniques; saw-tooth profiles, reverse-profile repetitive diving, too rapid ascents, generally poor buoyancy skills, pushing NDLs, and has at best a rudimentary grasp of dive planning, tables, or their dive computers
2. Sloppy diving skills - as above - while unlikely to put the typical recreational diver in a chamber, are likely to produce sub-clinical DCS or so called "silent bubbles" in the blood stream and body tissues
3. The silent bubbles from sub-clinical DCS that are experienced by typical recreational divers with sloppy dive skills are likely to produce symptoms of fatigue
4. Accordingly typical recreational divers with sloppy dive skills who dive nitrox - which reduces the ppO2 of nitrogen - will experience less bubbles, and therefor will experience less fatigue secondary to the sub-clinical DCS they incur as a result of their sloppy dive skills and techniques, as compared to a group of typical recreational divers with similarly sloppy dive skills diving air

:cool2:​

But seriously, let's be more objective and consider it this way...

• the data from well-controlled studies (ie all participants are placed in a chamber and subjected to exactly the same dive profiles relative to depth, time, ascent rate, etc which are controlled by the scientists conducting the study) show that divers using nitrox have no statistically significant difference in post-dive fatigue as compared to divers on air
• the data from poorly-controlled studies (ie: typical recreational divers are allowed to jump in the water and do their own thing) show that those who dive nitrox are less fatigued than those who dive air
• so it would appear reasonable to conclude from the literature that people who dive in a well-controlled fashion exhibit less fatigue than people who dive in a poorly-controlled fashion... irrespective of their choice of breathing gas.

So my suggestion is that you do what I do: Try to NOT exhibit the dive skills of a typical recreational diver... but dive nitrox just in case.

​

 

[JohnN]

Ah, yes. That ol' chestnut again! Is your MD a dive physician?

----snip------

So my suggestion is that you do what I do: Try to NOT exhibit the dive skills of a typical recreational diver... but dive nitrox just in case.

​

My favorite TS&M quote goes something like: "The plural of anecdote is not data"

BUT

I personally feel less tired doing multiple dives on EAN
When I'm doing 3 dives/day it does substantially increase my bottom time on that last dive
Even when I don't hit my NDL limit, I believe the "extra" time decreases my chance of an up close and personal experience with DCS


Well worth the money to me

 

[RJP]

I personally feel less tired doing multiple dives on EAN
When I'm doing 3 dives/day it does substantially increase my bottom time on that last dive

Well worth the money to me

It's the placebo effect: You're not really less tired. You just feel less tired!

:d

 

[Hawkwood]

I also feel less tired when I'm doing lots of dives a day on Nitrox.

However that happens usually when I'm diving in warm water.

I don't have to get in and out of a dry suit with lots of fleece, wear 24 lbs of lead, do this all at 5,000 feet, climb down embankments in full gear, dive in water that averages 45F, etc. I'm usually tired by the time I get into the water.

Yup, when I have the opportunity to dive lots of dives on Nitrox, I'm not as tired as my normal diving makes me. Must be the Nitrox

 

[Aotus]

I'm a very new diver. I completed OW last month. I'm just now completing my Nitrox Certification. I plan to dive mostly on vacations to the warmer waters.

The questions is: Do I need I need to buy an O2 analyzer or will most dive resorts or live-aboard operators have one that I can use. I expect to be able to dive 2-3 weeks a year.

Thanks in advance for your advice.

YES. And really, a CO tester too. they aren't all very expensive. I got my analyzers on eBay for 30% and 50% the cost of a new one. Yes, it costs some money, and maybe you'll be fine without, read some of the stories of close calls and deaths owed to some bad gas at a "reputable" dive shop on vacation.

 

[JohnN]

It's the placebo effect: You're not really less tired. You just feel less tired!

:d

My analyst told me
That I was right out of my head
The way he described it
He said I'd be better dead than alive
I didn't listen to his jive
I knew all along
That he was all wrong
And I knew that he thought
I was crazy but I'm not
don't know

My analyst told me
That I was right out of my head
He said I need treatment
But I'm not that easily led
He said I was the type
That was most inclined
When out of his sight
To be out of my mind
And he thought I was nuts
No more ifs or ands or buts

They say as a child
I appeared a little bit wild
With all my crazy ideas
But I knew what was happening
I knew I was a genius...
What's so strange when you know
That you're a wizard at three
I knew that this was meant to be

Now I heard little children
Were supposed to sleep tight
That's why I got into the vodka one night
My parents got frantic
Didn't know what to do
But I saw some crazy scenes
Before I came to
Now do you think I was crazy
I may have been only three
But I was swinging

They all laugh at angry young men
They all laughed at Edison
And also at Einstein
So why should I be sorry
If they just couldn't understand
The idiomatic logic
That went on in my head
I had a brain
It was insane
Oh they used to laugh at me
When I refused to ride
On those double decker buses
All because there was no driver on the top

My analyst told me
That I was right out of my head
But I said dear doctor
I think that it's you instead
Because I, I got a thing
That's unique and new
To prove it I'll have
The last laugh on you
'Cause instead of one head
I got two
And you know two heads are better than one.​

 

[Aotus]

Thanks for sharing your experience and wisdom.

As for why a new diver would go straight to nitrox, I'm 71 years old and my MD recommend I use nitrox to avoid fatigue on multiple dives. I don't plan on going deeper than my training (60ft) until I have a number of dives and more training. Just seeking an edge.

I'm learning and really appreciate the sharing on this board.

I don't know if it's my comfort level in the water or that I now only dive 32%, but I used to feel wiped out after most dives, and now I'm happy and ready for lunch and another dive. there seems to be disagreement even among agencies about whether EANX influences how you feel - PADI says it doesn't, I think it's PSAI or maybe IANTD that says it does. If it works for you, great! Who cares if it's a physiological outcome of the different mix or a placebo, either way you're having more fun (and get more NDL time and shorter SIs).

 

[Storker]

You're not really less tired. You just feel less tired!

Good enough for me


--
Sent from my Android phone
Typos are a feature, not a bug

 

[scubafanatic]

I like having my own analyzer, not having to participate in the mad rush, pre dive mob scene where a bunch of divers are all trying to hunt down and then wait in line for the 'group' analyzer to be passed around.....hate that 'being in a rush' feeling, ......or trying to hunt down the 'group' analyzer that someone set down somewhere and now can't be located !