deep air

[gcbryan]

This thread gives me a headache much like last week's. Thal indicates that NOAA and other scientific divers need to be proficient with diving to 190ft on air because that's their job which is fine. Everyone else advocates that all recreational tec divers are best served utilizing gas mixtures greatly reducing nitrogen and narcosis. Why does this arument continue?

The argument continues since the point attempting to be made is that deep air dives can be done safely even if there are better ways to do it in most cases.

One side doesn't admit this and attempts to skew the reality which is never a good thing regardless of how you actually dive. It's better to stick with the facts rather than to exaggerate them.

 

[Scott L]

The argument continues since the point attempting to be made is that deep air dives can be done safely even if there are better ways to do it in most cases.

One side doesn't admit this and attempts to skew the reality which is never a good thing regardless of how you actually dive. It's better to stick with the facts rather than to exaggerate them.

I suppose you are right. If availiability and cost of HE were not the issue that it is I beleive everyone would be in more agreement. Those who's training agencies have rigid guidlines should probaly not be condensending with those who have dived in another fashion for 40+ years with acceptable results...

 

[SurDo2]

I can understand why you feel this way. It is a recreational perspective that is founded in the total confidence of always having the perfect mixture available.

As a professional diver, I have experienced nitrogen narcosis on trimix (a gas pusher error), I've oxtoxed, have experienced HPNS, CO2 excess, blacking-out for a number of reasons while at pressure. You dive long enough professionally, all sorts of things are bound to happen. Being able to maintain composure and act appropriately when your mental faculties are failing has saved my life. Learning to deal with an improper mixture has been valuable at depth.

As you are a recreational diver and are guaranteed never to run into any of these problems, I agree you will never have any need to develop these skills. If you ever are, you will be unprepared. I wish you luck.

Very well said, and very well timed. I'm sitting in front of the fire enjoying a glass of scotch after hitting 200 today on air. Now as to why the engineer spec'd the outfall at 200 no one can figure out.

Cheers.

 

[Kevrumbo]

The argument continues since the point attempting to be made is that deep air dives can be done safely even if there are better ways to do it in most cases.

One side doesn't admit this and attempts to skew the reality which is never a good thing regardless of how you actually dive. It's better to stick with the facts rather than to exaggerate them.

I suppose you are right. If availiability and cost of HE were not the issue that it is I beleive everyone would be in more agreement. Those who's training agencies have rigid guidlines should probaly not be condensending with those who have dived in another fashion for 40+ years with acceptable results...

The instructors of those rigid training agencies won't admit to doing the occasional deep air dive -however well they can justify doing it- because of potential professional liability issues --and not just the "do as I say, not as I do" hypocrisy. I fully sympathize & can respect that fwiw. . .

 

[Karel26]

I would just like to know isn't it dangerous to dive with just air
deeper then 150feet. . I've read a diveing magezine in South Africa
and they advice that you don't dive with air deeper then 150feet,
they say 120feet is even pushing it. . What will the dangers be
except from getting narked? ?

Live todive and dive to live. . . . :burnout:

 

[Tortuga68]

I would just like to know isn't it dangerous to dive

Yes it is

 

[DCBC]

I would just like to know isn't it dangerous to dive with just air deeper then 150feet. .

As you have less than 50 dives, yes it is dangerous for you to dive on air to 150'. It would also be dangerous for you to dive to 150' on Trimix. Nothing against you as an individual, but your level of experience doesn't indicate that you would be ready for a 150' dive, unless you were a passenger in a submarine.

So what would make you safe to dive to 150'? Further experience for starters. Instruction in Trimix isn't enough, as it may address the narcosis situation, but may not deal with the other hazards of deeper water. Because a Diver has a Trimix card does not mean that he can dive to 300' on Trimix safely. There are those who may try to convince you that this is the case, but that's not necessarily true.

The argument that has been made, is that if you want to be safe you use the right gas. I'll wager that these same individuals have dove air to 100'. Why did they not use Nitrox or Trimix on any dive past 50'? Nitrogen narcosis will affect them as soon as they descend and at 50' their performance and reaction time will be measurably lower! You can see the flaw in their argument...

The answer would be, well I am safe to dive past 50' because I can deal with the effects of narcosis at that depth. Yes, in the same way as I and others can deal with the effects of narcosis at 200'. Because they don't possess the necessary experience, they throw stones and come back with "You should pick the right gas! You take unnecessary risks, etc."

They do not wish to learn how do dive deep air safely. Clearly it's faster to get a Trimix card. Yes, it's far easier. That does not mean Trimix is the only way to dive safely at that depth.

 

[cfenton]

The argument continues since the point attempting to be made is that deep air dives can be done safely even if there are better ways to do it in most cases.

One side doesn't admit this and attempts to skew the reality which is never a good thing regardless of how you actually dive. It's better to stick with the facts rather than to exaggerate them.

The argument continues because people like Karel26 read this board. I don't care if any of you guys dive deep air. But when people say that 'there is wisdom in diving deep air before trimix', 'you have no business diving trimix if your not comfortable with deep air', and my new favorite 'diving deep air is more personally fulfilling', that becomes misleading to newer divers reading this board.

The simple fact of the matter is that there is a better gas for every depth range then air. The only reason that we're having this 'debate' is that we evolved to breath 21% oxygen and 79% nitrogen on the surface. That makes it familiar, cheap and easy to get. That's it. Collectively we, of the technical diving community know, there is alway a better choice if you ignore cost and logistics. This macho, personal fulfillment, bs is steaming load.

If people want to dive deep air, thats great. But why not be honest about the motivation?

I would just like to know isn't it dangerous to dive with just air
deeper then 150feet. . I've read a diveing magezine in South Africa
and they advice that you don't dive with air deeper then 150feet,
they say 120feet is even pushing it. . What will the dangers be
except from getting narked? ?

Live todive and dive to live. . . . :burnout:

Getting narced is the main danger.

 

[DCBC]

The argument continues because people like Karel26 read this board. I don't care if any of you guys dive deep air. But when people say that 'there is wisdom in diving deep air before trimix', 'you have no business diving trimix if your not comfortable with deep air', and my new favorite 'diving deep air is more personally fulfilling', that becomes misleading to newer divers reading this board.

As you have pointed-out, this is a Technical Discussion area and not for Basic discussion. I'm sure Karl26 can easily ascertain this as well and can ask for clarification on anything he finds misleading.

The simple fact of the matter is that there is a better gas for every depth range then air.

As I believe that you are not a hypocrite, I know that you never dive below 50' on air, as there is in-fact a better gas to use. Some of us however, have a different operational "air envelope" than you do.

 

[cfenton]

As I believe that you are not a hypocrite, I know that you never dive below 50' on air, as there is in-fact a better gas to use. Some of us however, have a different operational "air envelope" than you do.

You got it. I haven't dived air in years at any depth.

The argument that has been made, is that if you want to be safe you use the right gas. I'll wager that these same individuals have dove air to 100'. Why did they not use Nitrox or Trimix on any dive past 50'? Nitrogen narcosis will affect them as soon as they descend and at 50' their performance and reaction time will be measurably lower! You can see the flaw in their argument...

The answer would be, well I am safe to dive past 50' because I can deal with the effects of narcosis at that depth. Yes, in the same way as I and others can deal with the effects of narcosis at 200'. Because they don't possess the necessary experience, they throw stones and come back with "You should pick the right gas! You take unnecessary risks, etc."

This argument really is asinine. You know full well that there is a world of difference between the effects of narcosis at 50' compared to 200' for every diver.

Where to draw the line for narcosis reasons is arbitrary - point taken. But, that doesn't mean that no line should be drawn.

I'm not for a second arguing that you can't do air dive < 190' and come back alive again and again. I'm not arguing that you can't learn to manage narcosis. I have extremely little experience with either, and therefore would be a fool to make those statements. What I AM saying is that there is a better gas for these dives and there is no NEED to ever dive deep air or learn to manage narcosis.