what the different between using Nitrox and Normal Air to dive???

[PfcAJ]

"NITROX breathing gas mixtures are normally used for shallow dives. The most benefit is gained when NITROX is used shallower than 50 fsw, but it can be advantageous when used to a depth of 140 fsw.

Advantages and Disadvantages of NITROX Diving.

The advantages of using NITROX rather than air for diving include:
Extended bottom times for no-decompression diving.
Reduced decompression time.
Reduced residual nitrogen in the body after a dive.
Reduced possibility of decompression sickness.
Reduced Nitrogen Narcosis

The disadvantages of using NITROX include:
Increased risk of CNS oxygen toxicity.
Producing NITROX mixtures requires special equipment.
NITROX equipment requires special cleaning techniques.
Long-duration NITROX dives can result in pulmonary oxygen toxicity.
Working with NITROX systems requires special training.
NITROX is expensive to purchase."

The above quote is from the US Navy Diving Manuel. I will try to attach a copy but it is a big file so it may not work.

To be clear they did NOT tell me it could not be used at depth just that the increased risk far out weighed the benefits. Which brings me back to my original question. Is anyone giving oxygen tolerance tests to people before they take a Nitrox class?

PS: The file did not seem to attach. I can email a copy to anyone who would like one.

Once again, oxygen tolerance tests really don't matter at all, nor is there any data to support reduced narcosis affect. If you can find some data to support that, please share.

 

[Rich Keller]

Oxygen poisoning and narcosis are two very different things. Everyone deals a little differently with both of these effects that is what the test is for. In my application the deeper we went the lower the O2% was in our mix so tolerance became more of an issue not less. That is why we had to take that test. Narcosis and the bends also are different for everyone. So can I assume no one is giving this test before a Nitrox class? Can I hear from someone who is teaching Nitrox?

 

[BKP]

"NITROX breathing gas mixtures are normally used for shallow dives. The most benefit is gained when NITROX is used shallower than 50 fsw, but it can be advantageous when used to a depth of 140 fsw.

Advantages and Disadvantages of NITROX Diving.

The advantages of using NITROX rather than air for diving include:
Extended bottom times for no-decompression diving.
Reduced decompression time.
Reduced residual nitrogen in the body after a dive.
Reduced possibility of decompression sickness.
Reduced Nitrogen Narcosis

The disadvantages of using NITROX include:
Increased risk of CNS oxygen toxicity.
Producing NITROX mixtures requires special equipment.
NITROX equipment requires special cleaning techniques.
Long-duration NITROX dives can result in pulmonary oxygen toxicity.
Working with NITROX systems requires special training.
NITROX is expensive to purchase."

The above quote is from the US Navy Diving Manuel. I will try to attach a copy but it is a big file so it may not work.

To be clear they did NOT tell me it could not be used at depth just that the increased risk far out weighed the benefits. Which brings me back to my original question. Is anyone giving oxygen tolerance tests to people before they take a Nitrox class?

PS: The file did not seem to attach. I can email a copy to anyone who would like one.

They missed one "CON": 6 - 12 bucks extra / fill

Nope... they got that one too... last bullet... Go Navy...

 

[Rich Keller]

BKP, I have mixed my own gas for other applications and it should cost little more then a regular fill not 6-12 dollars. And YES...Go Navy...

 

[PfcAJ]

Sigh. I get that you have an opinion. What I'm asking for is data to support your opinion.

 

[Rainer]

Science is for chumps.

 

[Rich Keller]

PfcAJ, This is not my opinion! This is what the Navy thinks! The only reason I know any of this is from me asking them what they thought. Still no one has answered my question and it is simple! Is the test being done or not??????

 

[BKP]

BKP, I have mixed my own gas for other applications and it should cost little more then a regular fill not 6-12 dollars. And YES...Go Navy...

Yeah, well... what it "should" cost is one thing... I used to get a break at my LDS for 32%... however, I've found most on-site sources, especially where they don't bank it, are $12 to $22/fill for 32%...

 

[Rainer]

PfcAJ, This is not my opinion! This is what the Navy thinks! The only reason I know any of this is from me asking them what they thought. Still no one has answered my question and it is simple! Is the test being done or not??????

You know who is doing these types of tests? Scientists.

Here's what they have to say. Feel free to educate yourself (warning: reading required). Make sure to pay particular attention to Donald's work that basically demonstrates the absolute futility of testing for a person's particular "oxygen tolerance".

Oxygen and the Diver K. Donald

Oxygen Poisoning in Man K. Donald

Rubicon Research Repository: Item 123456789/4855

Rubicon Research Repository: Item 123456789/3991

Modeling pulmonary and CNS O2 toxicity and estimation of parameters for humans -- Arieli et al. 92 (1): 248 -- Journal of Applied Physiology

The Deco Stop

Some nice "summary" threads:

The Deco Stop

http://www.scubaboard.com/forums/258723-post31.html

The Deco Stop

 

[Rich Keller]

BKP, They are not mixing fuel for the space shuttle! Why do they say it should cost this much? I have mixed trimix for dives to 700' and even though the O2% was much more critical it is not that hard!