Deep Diving Query

[striking viking]

Have a question about deep diving. I know that PADI considers any dive below 60 ft. a deep dive, but lets face it, it's not all that deep. I have personally not dived below 90 fsw-with 30 ft vis in 45 degree F temp-and don't plan on diving much below the 100-120 ft. range in those same conditions. For me that seems like plenty enough, but if I ever wanted to join the "20,000 leagues under the sea club," is there a special class that is available, or do you simply take the plunge with another experienced diver? What's it like for those of you that have dived below 130 ft. and what conditions were you in? Were there any nervous moments, or was it no big deal?

 

[sea nmf]

I did take a class - PADI has a deep dive cert course. However, now that I'm experienced, I would say the class wasn't necessary.

What the class shows you is the effect of narcosis. You don't really feel as if you are impaired, but there is evidence. That was sort of important, I guess.

I dive in Puget Sound and the deep dive was to 100'. Here is it dark, cold, with low viz. And nothing but star fish anyway.

However, in the Caribbean, it is so easy to go deep because it doesn't get dark and there is much to see. Parts of Canada are like that also.

So there will be a time when you will happily go below 100' and think it is not affecting you. But, trust me, it is.

 

[SubMariner]

As has already been pointed out, "deep" in warm tropical waters is vastly different than "deep" in cold North American (or UK) waters.

Factors to consider:

1) - vis
2) - temperature
3) - exposure protection
4) - general equipment
5) - narcosis

1) Pretty self explanatory. Except a free ascent from 70' in Tobermory is quite different that the same in Cozumel. In the latter you can almost always see the surface, even at 110-120'. Not so in the former, where you usually wind up using a light after about 60' or so. Seeing is very important to a lot of divers. Some get panicky & lose control. Especially when they are in midwater and have no visual point of reference.

2) Deeper is colder. Again, not neccesarily a big deal, unless you are unprepared for it. That's also why most tables recognize the physiological impact this has on divers. There are rarely noticeable thermoclines in tropical waters while they are the norm in fresh water. For example, a surface water temperature of 77F can wind up being 54'F at 65'.

3) This is obviously tied to #2. It tends to be a somewhat subjective item. However, most people agree that you don't need much in the tropics, even at depth. Not so freshwater. And of course the amount or type of exposure protection can impact your mobility.
Also, what about the fact that neoprene compresses at depth?

4) Also linked to #2. Not too many people using drysuits in the tropics. Or cold water regulators. It also has an impact on the type of BC some people choose.
Also, what about redundant air supplies? If you are routinely diving deep, what type of redundant air supply to carry? And how?
There is also whether or not the regulator is balanced: an unbalanced reg is much harder to breathe from at depth.

5) Narcosis doesn't just manifest itself as "rapture of the deep" or "inappropriate behaviour". It sometimes shows up as an increased level of stress or anxiety in the diver. People who are not experienced in diving deep may not recognize ANY of these symptoms. Which could have some serious consequences.

Conclusion: there is LOTS to learn about diving deep; I've only touched on some of the main points. Doing your first dives with a qualified Instructor is one of the best ways to start learning.

~SubMariner~

 

[100days-a-year]

I'd suggest a least a year of diving or 50-100 dives before doing anything.Then ,if the fancy strikes take courses from one of the "tech"certifying agencies.Do lots of research on your choices and good luck.Every year I go deeper ,farther and dive more often.I have learned one thing tho...if you get impaired enough to notice it it's time to go.This is supposed to be fun

 

[Steve_C]

You will go through your air much faster. You will be much less alert. Study up on it before you do it and follow the other advice above.

And don't just take the experienced divers word for it that they are experienced. Scuba is full of divers that exaggerate their skill/experience.

 

[kotik]

You also run through NDL time much quicker. And, if diving nitrox, the MOD becomes more and more of a concern.

The reason depth starts to become a concern, is because so many reasons start piling up. The situation becomes more and more complicated, while at the same time narcosis deteriorates your effectiveness at quickly dealing with complications.

 

[Ste Wart]

OP hasn't logged on for 12 years, I doubt he's reading.

 

[kotik]

Drat!

Steve_C, I blame you totally for this, I'm innocent!!

 

[BDSC]

OP hasn't logged on for 12 years, I doubt he's reading.

Probably died doing a deep dive.

 

[Mr Carcharodon]

Has not logged in 12 years, but he is a "frequent poster". Apparently those designations are like certs that never expire.