70 replies to this topic

[Dive_Girl]

For example what would happen to a diver if accidentally the fill in there Nitrox tank was 50% Nitrox and 50% Air ?? and they didn’t test it or have it tested with an analyzer. would the diver be able to tell, would it taste funny in there mouth ? what could possibly happen.

I believe I understand your question B2B (over the years of diving, I have learned to try and understand the intent of divers' questions in regards to areas/subjects they are new in researching). If a diver mistakenly received a tank with EAN50 (approximately 50% Oxygen and 50% Nitrogen) and they didn't check it and didn't have an analyzer, I do not believe a diver would readily know the mixture had such a high O2 content just by breathing it from a regulator.

But for a diver to mistakenly receive that mix and actually dive it, a number of mistakes, not just one would likely have to occur. It would have to be a break down in the system which would mean there were errors from many different sources including diver error. It's not that it can't happen, however. So check, check, and recheck.

We have had a number of recent threads regarding Enriched Air (commonly referred to as Nitrox). I'll find them and link them shortly for your reference.

[Brinybay]

Well, the technical and commercial diving community gave up on air decades ago. It seems only recreational SCUBA is clinging onto it for God knows what reason. Maybe the 4 hour class is too much for people.

It's the algebra. Brought back bad memories of jr. high.

[BradfordNC]

Well, the technical and commercial diving community gave up on air decades ago.

technical community "gave up" on it? not sure this is realy true.

plenty in the "tech" community still use it.

i did a week of diving in Bikini Atoll.
12 dives with all depths below 100 fsw, some maxing out at 180 fsw.

all dives were done on NITROX 21, aka air.

deco was done on nitrox 75.

but maybe i wasn't diving "tech"
beats me.

the commonly available (banked) nitrox mixes can only be used to a limited depth.

trimix or other "exotic" mixes aren't necessary until a certain depth.
between those two areas, air is a perfectly acceptable gas to use.


as for the commerial dive industry, as with any industry that gets paid by the hour, time equals money.
the use of "exotic" gases (trimix, heliox, nitrox) allow for a much quicker job completion rate, which allows companies to move their divers on to the next job. the higher price of the gas is offset by the speed of the job, which equals higher profits for the company.

It seems only recreational SCUBA is clinging onto it for God knows what reason.

they are "clinging" onto it because it makes sense and there is no reason to ditch it.
its perfectly safe and far more readily available globaly than any other mix.

and as Walter pointed out, shallow dives have no need for it.
if diving shallower than 30 feet, you'll run out of air long before you'll run out of bottom time, so why waste the money on Nitrox??? it isn't going to make the dive any "safer"

[PerroneFord]

Yes,

You guys are right. I'm sorry. I'll shut up.

[6Gill]

A WELL taught nitox course will give you a better understanding of the gases,the math ect.I think that even if all you'll ever dive is air you walk away a better educated diver.I think it also makes understanding deco theory easier to.After taking a WELL taught course you can then make an informed decision.
Air,nitox,trimix,heliox ect are just tools in a box.Having the tools and knowing how to use them and undertanding their limitations and where they excell allows you to pick the proper tool for the job.There is a reason hammers come in different sizes and shapes.
As to fill...I fill my own so labour cost not an issue just time.Appox cost is CAN$5 for twins.(gas,electricity) We have an informal co-op for filling plus allows for the sharing of tanks ect.Example if a couple of us are going diving the tanks(doubbles,stage,deco) we can borrow the gear from those not diving.

[WreckWench]

Yes,

You guys are right. I'm sorry. I'll shut up.

Hey guy...no worries! This is how you, myself and others learn. We have honest, open and thoughtful exchanges.

If we have a few too many 'editorial comments' perhaps the discussions are more heated than they might otherwise be...but look at how much everyone has learned via this thread. And if you think people haven't then think again.

Perhaps the most important take away is that what seems so simple and straightforward in one environment may be totally different in another. Take for example the cheap cost of nitrox in 'cave country' whereby you get charged for nitrox by the cubic foot. With my SAC rates I too would ONLY dive nitrox and pay pennies on the dollar to what I have to pay now. (Yep I'm cheap so I dive air a lot.)

BUT....to my limited knowledge which now covers 12 years of diving and just shy of 1000 dives...I have only found gas sold by the cubic foot to be available in Florida. And technically on our Bahamas liveaboard but that is because it originated out of Florida.

So now people know that Nitrox is very cheap in PARTS of Florida and you now know its very expensive in other parts of Florida, the US and the world.

So no need to shut up...you can't learn if you don't ask or contribute...but realizing that things are different in different parts of the country or world is a HUGE first step to understanding why there are so many different opinions on how to do something. And NO...they are not all inherently right nor are they inherently wrong. But they usually apply to where the person dives and they are always valuable to us and others if we'll accept them at face value.

[Dive_Girl]

realizing that things are different in different parts of the country or world is a HUGE first step to understanding why there are so many different opinions on how to do something. And NO...they are not all inherently right nor are they inherently wrong. But they usually apply to where the person dives and they are always valuable to us and others if we'll accept them at face value.

great point WW!

[Bubble2Bubble]

Yes DG I think WW made a good point also!


I thought this from 6Gill was Spot On as well

Air,nitox,trimix,heliox ect are just tools in a box.Having the tools and knowing how to use them and undertanding their limitations and where they excell allows you to pick the proper tool for the job.There is a reason hammers come in different sizes and shapes.

The cost of filling Nitrox in my part of the Woods is 0.00 (best price I have seen yet)

Thats because they dont have any around here


B2B

[BradfordNC]

Perhaps the most important take away is that what seems so simple and straightforward in one environment may be totally different in another. Take for example the cheap cost of nitrox in 'cave country' whereby you get charged for nitrox by the cubic foot. With my SAC rates I too would ONLY dive nitrox and pay pennies on the dollar to what I have to pay now. (Yep I'm cheap so I dive air a lot.)

i still won't say nitrox in florida is "cheap"

i buy it by the cubic foot in cave country and for my last trip the nitrox bill was $180.

but oh well, the was incredible

[ScubaDadMiami]

. . . for my last trip the nitrox bill was $180.

Answer = CCR

[Dive_Girl]

Oh, BTW, Mike, yes nitrox does make your butt look big.

[Bubble2Bubble]

Yes DG Is saw that No Comment

Its possible this thread is dieing off so I want to post my favorite quote also..

DrBill

Oh, and as for making your "butte" (and I thought that was a geological formation) bigger... it is quite true. The absorption of the extra nitrogen in your tissues inflates them and makes everything bigger, especially the faster absorbing tissues. Add the effect of enlargement due to your mask and it's a wonder you can even fit into the same wetsuit when you dive Nitrox!

B2B

[Dive_Girl]

Hey B2B, it's your thread - so you can take it any direction you want - even if it is buttsidedown....

[BradfordNC]

. . . for my last trip the nitrox bill was $180.

Answer = CCR

nah, i don't feel like spending $15,000 on something i'd get limited use out of