Nitrox the Wonder Gas

[JeffG]

Still researching for safety stops and happened across this article, was more than a bit surprised by the statements made. http://www.scubadiving.com/article4545

Why were you suprised?

 

[battles2a5]

I don't think anyone will contest the fact that nitrox facilitates longer bottom times, especially when making repetitive dives. That's why I got the cert, and that's why many of the divers I know got it. That being said, I don't see how it could be a waste of money. Especially when you consider the amount of money we spend on gear, training, and actually getting to your dive destination. If you spread the cost of a nitrox cert and fills over a year, I would bet that the bottom-time benefit would increase the bubbles blown per dollar spent ratio significantly.

The other "claims" in the article have always been described to me as ancillary benefits at best, not a reason to get the card.

 

[String]

Okay, I'm making my predictions now...
1) Those who use Nitrox will (having paid for the class, the computer and the tank) swear by how much it helps.

I use nitrox regulary, have all my equipment cleaned and ready for it and also an instructor with it. However i wont swear by how much it helps. Like anything else its a tool for a job. I use it because it enables me to extend my no stop time at a depth and/or decrease my decompression time. No other reasons.

3) Virtually NO divers who are Nitrox certified will say it was a waste of time and money.

Depends what you use it for. I've not noticed any reduction in narcosis, fatigue, SAC or anything else. If you dont dive to or beyond NDLs or do multi dives over multi days i doubt theres a use for it. If you do, there is.

 

[TSandM]

The statements in the original post are correct. Nitrox does not reduce air consumption for the stated reason, and is not less narcotic than air.

Nitrox gives you longer "NDL" time at a given depth, within the MOD.

Whether one feels better diving Nitrox or not is debatable. The quoted study would suggest it's a placebo effect. It may be related to the fact that people who get Nitrox certified are generally people with more dives under their belts, and they're managing their ascents better.

Nitrox is not a wonder drug.

 

[MXGratefulDiver]

Still researching for safety stops and happened across this article, was more than a bit surprised by the statements made. http://www.scubadiving.com/article4545

What Nitrox Won't Do
Claim #1
Nitrox reduces narcosis. This sounds reasonable. If nitrogen causes narcosis and you're breathing less of it, you should have less narcosis. The trouble is, the depth range where you start worrying about narcosis (100 to 130 feet) is also where you have to stop using nitrox because of the risk of oxygen toxicity. Dr. Peter Bennett, who co-edited The Physiology and Medicine of Diving and wrote the chapter on inert gas narcosis, says the preventive value of nitrox is "very small, so marginal that I think it should be discounted."

Claim #2
Less gas consumption. This sounds reasonable too. If there's more oxygen in each breath, presumably you don't have to take another one so soon and your gas consumption rate is lower. Unfortunately, it doesn't work that way because most of the oxygen you breathe is exhaled unused anyway. What drives the next breath is the need to exhale carbon dioxide, and that's not affected by what's in your tank.

Claim #3
Less fatigue. "Those long and tiring drives returning from a day of diving are over!" enthuses one dive shop's web site on the benefits of diving on nitrox. Is it really the "feel good" gas? The theory here is that the work of offgassing nitrogen is a major cause of diving fatigue, so less of it should leave you less tired. Many nitrox divers swear it's true, but Bennett cites a blinded study that proved otherwise. Using unmarked tanks, one group of divers was given nitrox, another was given air, and both were asked later how they felt. "There was no difference," says Bennett. "It's a placebo effect."

Claim #4
Deeper dives. Some divers think those green-and-yellow cylinders look serious and "techie," and associate that with going deep. In fact, nitrox introduces a new depth floor that's often shallower than the 130 feet we're used to. PADI's recommended depth limits are 110 feet for 32 percent nitrox and 95 feet for 36 percent nitrox. The penalty for going below the floor is serious, too. Many of us would risk chasing that eagle ray down to 150 feet on air (NO I WOULDN'T), but wouldn't think of it on nitrox.

Not surprising at all ... all this stuff is covered in any nitrox class. I know it's about slide 6 in mine ...

... Bob (Grateful Diver)

 

[wreckedinri]

Okay, I'm making my predictions now...
1) Those who use Nitrox will (having paid for the class, the computer and the tank) swear by how much it helps.
2) Those who have not gotten Nitrox certified will agree whole-heartedly with the good doctor's statements.
3) Virtually NO divers who are Nitrox certified will say it was a waste of time and money.

I have no stake in the outcome. I'm just curious to see how the discussion plays out. Now, let the games resume!

Ok, It's crappy outside and the bulk of my work is done for the day so I'll spend a minute or two and throw in my $.02

Okay, I'm making my predictions now...

Mr. Guba, I think I'm gonna surprise you.

1) Those who use Nitrox will (having paid for the class, the computer and the tank) swear by how much it helps.

I was certified in 95 (#11,860), the instructor was trying to sell us the same line about how it was a miracle gas, how we would feel so great after using it, blah, blah, blah. We, the guys I dived with and I, were more interested in getting certs to access higher O2 mixes as deco gas. It seemed a better way to go than only using industrial O2 at 20fsw. Home mixing was in its infancy and not being done where I was. For deco gas - which is off thread so this is all I'll mention - it is indespensible. For recreational diving; if you are only a "vacation diver", save your money! If you are a regular "rec-diver" then one has to weigh the benefit of extended BT vs cost of gas and training. IMHO, the best way to use NITROX is to dive the gas but use air tables/computer for the added safety that doing so affords. As for feeling better, stronger, less sleepy after diving with NITROX my first inclination is to say BULL CRAP - but I'll be more tackful and state simply; that has not been my experience.

2) Those who have not gotten Nitrox certified will agree whole-heartedly with the good doctor's statements.

Well, as stated, I am certified and I do agree with the Doctor's statements.

3) Virtually NO divers who are Nitrox certified will say it was a waste of time and money.

For me, if I was doing typical recreational dives, I'd save my money. Stating that something was a waste when it adds to one knowledge base is a bit strong, as added knowledge is never a waste. But, I think that you can have a heck of alot of fun and be a darn good diver without NITROX certification.

I have no stake in the outcome. I'm just curious to see how the discussion plays out. Now, let the games resume!

I'm with ya Mr. Guba . . . this should be fun!

 

[MXGratefulDiver]

For recreational diving; if you are only a "vacation diver", save your money!

... unless, of course, you're one of those divers who enjoys doing five of six dives a day over multiple days on your vacation ...

The advantages of nitrox have strictly to do with the relationship between the amount of nitrogen you put in your body, the amount of time you stay at a given depth, and the amount of time you have to stay out of the water between dives to offgas.

Less nitrogen means you can reduce one or more of those factors. If you're doing multiple dives per day over multiple days, the (negligible) cost of a nitrox class and the extra cost of the gas may be worthwhile ... depends on how important the extra dives and bottom time are to you.

... Bob (Grateful Diver)

 

[mike_s]

What Nitrox Won't Do
Claim #1 - Nitrox reduces narcosis.
Claim #2 - Less gas consumption.
Claim #3 - Less fatigue. [snip] "It's a placebo effect."
Claim #4 - Deeper dives. .

I think anyone who's taken the class already knows at least #1,#2, & #4

But I think most of us would disagree with #3 statement that it doesn't help the statement of "Less Fatigue". On multi-dive days I can tell a bid difference later in the day if I'm diving Nitrox verses air. Maybe it is the placebo-effect, but from a week long unscientific dive experiment I did last week where I dove all dives with Nitrox except one days worth to see how I'd feel later after diving air, I was much more tired the evening the day I dove only air and not the Nitrox days.

Yes it's debatable, but I feel confident that with my test I've proven to myself that it I am less fatigued after diving Nitrox. There's not a whole lot that's going to change my mind.

I've heard they've done studies and tests with this, but I question these because you can minipulate any test/poll/scenario for outcome if wanted. (Look at the "Pepsi Challenge" 'tests' done in the 1980's with consumers. If someone gives you the choice of a hot, flat, Coca-cola or an Ice cold fresh Pepsi during a taste test, 99% of us are going to choose the Pepsi on that test as being the better drink.)

 

[MXGratefulDiver]

I think anyone who's taken the class already knows at least #1,#2, & #4

But I think most of us would disagree with #3 statement that it doesn't help the statement of "Less Fatigue". On multi-dive days I can tell a bid difference later in the day if I'm diving Nitrox verses air. Maybe it is the placebo-effect, but from a week long unscientific dive experiment I did last week where I dove all dives with Nitrox except one days worth to see how I'd feel later after diving air, I was much more tired the evening the day I dove only air and not the Nitrox days.

Yes it's debatable, but I feel confident that with my test I've proven to myself that it I am less fatigued after diving Nitrox. There's not a whole lot that's going to change my mind.

That's a lot like the argon arguments ... to which I respond, I don't really care if it's all in the mind. After all, it's MY mind ... so if I feel less tired (with nitrox) or warmer (with argon) then whether the effect is real or imagined is irrelevent ... I'm getting what I paid for.

... Bob (Grateful Diver)

 

[DandyDon]

Sorry, not reading all the stuff here. I just hate to dive with divers who don't get Nitrox carded.