why hasnt nitrox replaced compressed air completely?

[beanojones]

But although in my years of diving I've never seen anyone bent, and I think about my profiles as well as monitor my computers closely, "undeserved hits" come to mind. So when I'm doing 1-2 weeks (or 3-4 days in cold water) of 3-4 tank days I feel as as an old fat guy its in my best interest to reduce n2 loading, if that costs me $150-200 over the course of a big trip, that's a reasonable expense for a not statistically proven margin of "safety" but measurable reduction of n2.

And once you add the word "Trip" into the equation, then Nitrox can make a large safety difference, because if the trip ends with flying you definitely want as little N2 as possible, because the ascent to altitude dramatically changes things.

 

[MaxBottomtime]

Read this;
http://archive.rubicon-foundation.o.../123456789/8005/AAUS_2008_1-11.pdf?sequence=1

 

[James R]

I don't care what has been scientifically proven, or what some people call placebo effects, or anything else. I know that if I am on a trip using Nitrox on every dive where it's appropriate for the depths (shallower than the MOD), I use it. I absolutely feel less tired after a day of diving 4-6 times a day.

 

[cmulvaney]

I sent an inquiry on this subject to The International Board of Undersea Medicine (IBUM).
International Board of Undersea Medicine | Hyperbaric Medicine | Undersea Medicine Training & Education | Diving Medicine
This is my exchange with them thus far.

Jeffrey Bertsch jeffbertsch@earthlink.net via christophermulvaney.com	8:40 AM (5 hours ago)		​
to cm

Christopher, there is a lot of empirical information about how a diver feels using enriched air nitrox (EANx). Feelings are difficult to quantify in scientific studies and that is probably why there is so little literature on the subject. It would stand to reason that when there is less of a narcotic gas (nitrogen) in a breathing mix that one would feel less "fatigued" after a dive. I have not performed a recent literature search but when I worked at Duke we did a lot of studies involving EANx and the use of O2 for decompression. Among the test subjects, there were a lot of reports that divers felt less fatigued after these types of dives. By using key words for authors in a search like Richard Moon, Richard Vann, Caroline Fife or Claude Piantadosi you may have better luck in finding some pertinent literature. I personally do not agree with the study you cited and am a little skeptical of its conclusions if it was truly a double-blind, peer reviewed study. The sampling of only 11 divers is certainly not enough to support the author's conclusion. In the early days (1980's) there was some misinformation published about the use of EANx--mostly based on the fear of the unknown.

Dick Rutkowski and Dr. Morgan Wells pioneered the use of EANx while still at NOAA. You may find some of their published papers on line or at Dick's websitewww.hyperbaricsinternational.com

I have worked with Dick and Morgan for many years and was in the soup with them early on by advocating the use of EANx for it's many benefits to divers along with the safe use of oxygen for decompression and the first aid for decompression illnesses. I still advocate its use and still dive using EANx to this day.

Hope this helps in your quest for accurate information. ~jeff




-----Original Message-----
>From: cm@christophermulvaney.com
>Sent: Jul 9, 2014 9:52 PM
>To: jeffbertsch@earthlink.net
>Subject: Web Form Submission
>
>The following information was submitted on July 9, 2014 @ 8:52 pm:
>
>-------------------------------------------------------
>
>Name: Christopher Mulvaney
>
>Email: cm@christophermulvaney.com
>
>Subject: O2 Question
>
>Comments: Hello, I have a question I hope you can answer. I have been scuba diving for almost 35 years. I am looking for research on Nitrox diving. Specifically on whether feeling better after a nitrox dive vs an air dive and the physiological responses differentiating the two different kinds of diving. I did find a study that only included 11 divers and said it was a placebo effect and did nothing but waste money. I dive nitrox 90% of the time and do feel better. Any help would be greatly appreciated.
>
>-------------------------------------------------------
>
>



​

Christopher Mulvaney <cmg33k@gmail.com>	11:59 AM (2 hours ago)		​
to Jeffrey

Thank you very much for your time and help.
Chris


​

 

[Doc]

There was with all seriousness a yellow/green nitrox SNORKEL and a Spare Air just to reinforce pointless. It's all marketing.

You haven't seen this month's SDM?

And you're so last year, Stringo...

 

[Blyslv]

And once you add the word "Trip" into the equation, then Nitrox can make a large safety difference, because if the trip ends with flying you definitely want as little N2 as possible, because the ascent to altitude dramatically changes things.

Are you saying that the 24 rule of thumb isn't good enough? If I have a flight on Thursday at 2pm (1400hrs), isn't it enough to simply stop diving by noon or 1pm on Wednesday? I hope so because that is my current plan!

 

[MXGratefulDiver]

Are you saying that the 24 rule of thumb isn't good enough? If I have a flight on Thursday at 2pm (1400hrs), isn't it enough to simply stop diving by noon or 1pm on Wednesday? I hope so because that is my current plan!

Ah, but by using nitrox, I'd be able to dive until 8 PM for that same flight ...

... Bob (Grateful Diver)

 

[redacted]

Ah, but by using nitrox, I'd be able to dive until 8 PM for that same flight ...

... Bob (Grateful Diver)

Do you know that from experience or do you have a computer that provides that level of planning information? If the latter, what is the computer?

 

[boulderjohn]

Read this;
http://archive.rubicon-foundation.o.../123456789/8005/AAUS_2008_1-11.pdf?sequence=1

As I said, I have only seen one study, and its procedures were so laughable that you could not draw any conclusions from it.

---------- Post added July 10th, 2014 at 03:03 PM ----------

Are you saying that the 24 rule of thumb isn't good enough? If I have a flight on Thursday at 2pm (1400hrs), isn't it enough to simply stop diving by noon or 1pm on Wednesday? I hope so because that is my current plan!

Who recommends a 24 hour rule of thumb?

The standard DAN and most agencies follow is 12 hours after a single dive and 18 hours after repetitive dives.

 

[MXGratefulDiver]

Do you know that from experience or do you have a computer that provides that level of planning information? If the latter, what is the computer?

It's my agency-recognized waiting period for nitrox users before flying ... 12 hours after a single dive, 18 hours after repetitive diving.

I know it from teaching nitrox classes for the past 10 years ...

... Bob (Grateful Diver)

---------- Post added July 10th, 2014 at 02:17 PM ----------

Who recommends a 24 hour rule of thumb?

The standard DAN and most agencies follow is 12 hours after a single dive and 18 hours after repetitive dives.

AFAIK, DAN actually recommends 24 hours ... they specify the 12/18 hours as "minimums" ...

... Bob (Grateful Diver)