Reaching Greater Depths

[freewillie]

Hi there

I'm travelling to the Andaman Islands for a week-long diving expedition after having completed my PADI Open Water Level 2 Autonomous Diver Standard course last year then diving 40m down the Belize Blue Hole for a total of 8 dives.

I am eager to advance my qualifications as I have ambitions to increase my ability and reach greater depths in due time.

Naturally I thought I would next complete an Advanced Open Water course but have read that the name is just deceptive marketing.

What is the best way to continue to advance my qualification with the aim of diving to greater depths as soon as is safely possible?

Any help or advice would be much appreciated!

Cheers
Tom

Just for semantic purposes.

1.) Certificate - document certifying that the person has completed a training course and requirements for certification.
2.) Qualified - having the training and experience for a position.

In the former you might have training and education but not the experience and skill. In the latter you have experience and skill. Think of it this way. After you pass basic OW training you have a certificate but you are not qualified to teach how to dive. You need a certain amount of hours and experience with additional training to teach how to dive.

The discussions on Advance Open Water training isn't that it is worthwhile, it's the difference between certified and qualified. You might be certified after AOW to dive to 130 ft. don't have the experience. Education and training is always worthwhile. But experience and training to be qualified takes time and dives. And the education makes the diving safer which is the ultimate goal.

What separates an experienced diver from an inexperienced diver is not how they dive when the dive goes as planned, it's how do they handle the situation where a complication or an emergency arises. Look at the current thread on "Another lesson learned." Conditions can change during a dive and how you handle that in large part will be determined by your experience. From another perspective, what would happen to you if something went wrong on a deep dive? If you are recreationally diving AL 85's then you have only 5 minutes at 130 ft. Not really worth the trip down. But what if spent 10 minutes? Now you are in deco and you didn't think to hang a decompression tank for your now obligatory safety stop. I guess taking your deep diving course to prevent this would have been worthwhile.

 

[Rhone Man]

We know that the first 20 dives are the most dangerous for a diver.

If you look at the diving death statistics, the bulk of them fall into two broad camps: rookie divers who did something too risky early on, and old buggers who keep doing intensive diving and don't appreciate their declining physical limitations (I am paraphrasing slightly).

It is my ambition to finish my days off in the latter category.

 

[dumpsterDiver]

Is this true? Not trying to make a statement, just curious.

http://www.scubaboard.com/forums/ba...39-half-dead-divers-their-first-20-dives.html

 

[pasley]

.... I think it is VERY smart to recommend that a diver take AOW (or whatever continuing education) they want ASAP! Getting more dives in with an instructor, SOON after certification should enhance the diver's safety and help "solidify" their skills AND make them much safer to continue on with diving on their own....

We disagree. If you said to get more dives using the skills already taught soon after certification with a dive master/instructor or a very experienced diver to mentor them the without adding new skills to them, then I could agree.

A new diver IMHO needs to dive and get practice and experience with the skills THEY ALREADY HAVE BEEN TAUGHT. Introducing a diver with 6 dives to diving to 100 feet or more is just plain dangerous. Many new divers with less than say 20 dives are still surfacing saying "Dang, I forgot to do my safety stop!." or saying "Whoa, I tried to stop at 15 feet but it just got away from me!" is not a good or safe idea. Add to that night diving with a diver who has say 7 or 8 dives and is not sure about anything, and you have IMHO a situation that is not optimal. I believe that it is much safer for a diver to gain experience with what they have already learned and get comfortable and confident with those skills before taking the next bite from the tree of increased skills/courses. It is bad enough that operators take divers to 150 feet for dive 5 (the first 4 being certification) in places like Belize Blue Hole. That is IMHO just the definition of STUPID both on the part of the operator and the diver who was taught better.

 

[Dr. Lecter]

Introducing a diver with 6 dives to diving to 100 feet or more is just plain dangerous.

As a general rule of thumb, maybe. As an absolute statement, bull.

 

[TMHeimer]

dumpsterDiver, pasley-- You both make good points that can be argued. I've always said it depends on the diver. And I agree with Dr.Lecter that a 6 dive diver to 100' GENERALLY isn't a good idea. I always recommend to students to start out by diving with someone who ideally is at least Rescue certified, or if not next best would be someone who is very experienced and can be a mentor --as you say pasley. This may be an ideal situation though. I had no such opportunity, so I went right to AOW (which was available at the time where I was in N. FL) and got some time with an instructor. Worked OK for me--maybe I was lucky.

 

[Kevrumbo]

If you have a nominal Surface Consumption Rate (SCR) of 15 liters/min or better, then you are ready to matriculate to Adv Open Water, Nitrox and Intro to Tech for starters. At 15 liters/min, your depth gauge in meters will indicate how much in bar you will consume in 5min (for a single 11 L/bar [AL80] stage cylinder) or in 10min (double 11L/bar for a total cylinder rating of 22L/bar). So for example, at 30m depth you will consume 30 bar of gas in 5min on a single 11L tank, or 30 bar in 10min on a manifolded twinset of 11L tanks. This is IMHO/IME is the easy base reference SCR for a warm water deep/tech diver in Gas Consumption Planning & Deco Profiling, both Pre-Dive and on-the-fly real time.

If you're not at that breathing rate now, then you're not ready for any further training to go deeper for longer . .

 

[Storker]

If you have a nominal Surface Consumption Rate (SCR) of 15 liters/min or better, then you are ready to matriculate to Adv Open Water, Nitrox and Intro to Tech for starters.

[...]

If you're not at that breathing rate now, then you're not ready for any further training to go deeper for longer . .

Oh, crap. Since my SCR - under my standard conditions, i.e. in a DS and cold water - normally is some 16-18 SLM, I guess I'd better hand in my AOW card. And ditch those plans for taking Nitrox.


EDIT:
To the OP, and snark aside: This is something you'll encounter regularly if you continue to read SB: Blanket statements based on the writer's own version of reality, i.e. his/her experiences. Divers are different, conditions are different and what's correct for one diver under certain conditions, will not necessarily be right for another diver or under other conditions. Remember that the advice you get here comes from anonymous strangers in the Internet, where everyone is an expert. At least in their own eyes.

---------- Post added November 11th, 2014 at 09:51 AM ----------

Now, back to the original topic, going deeper: I'm considering myself to be a fairly competent diver under the conditions I'm used to (moderate current, moderate chop, no hot-weather problems - but some cold-water challenges), and my personal depth limit is 30m/100ft. For me, there's enough cool things to see in the range from 0 to 30m, since I'm not particularly fascinated by wrecks (which often is the target for deeper dives, as deeper wrecks usually are better preserved than shallower wrecks).

Besides, for most divers, nitrogen narcosis starts to creep up on you somewhere around 30m, sometimes shallower, sometimes deeper. The problem with narcosis is that you usually don't notice it in the early stages, but it manifests itself as a form of mental impairment, decreasing mental bandwidth and generally slowing down your mind. For an inexperienced diver, that is a liability, since when we're inexperienced, we're usually task loaded to the gills just by being down there. Usually, we're just fine, but if something happens, you just might not have the necessary spare mental capacity to deal with it. Since I'm rather susceptible to narcosis, I've set my own limit on air to 30m, and quite often I even set a shallower limit. And if I ever were to plan a dive deeper than 30, I'd be doing that on trimix - after getting the appropriate training - since I'm often becoming rather stupid at those depths.

Another aspect to consider if you think about going deep, is no-stop time. Even at 30m, the maximum bottom time is just 20min, and on 40m, it's about 10min. We're talking about bounce dives unless you're deco trained and equipped. You won't have much time to really look at stuff.

Third, it's gas reserves. With my SAC and carrying a 10L 300 bar tank (about 100 cu.ft. by US notation), I have a very good fit between minimum gas and no-stop time at depths below OW limits: When I'm approaching no-stop time, I'm also down to the min pressure at that depth. If I were to dive an Al80, I'd be down below my minimum reserves before I even hit no-stop limits. And 20min isn't a very long dive...

As others have said, going deep just for the sake of going deep is generally considered as meaningless by many divers. If you want to explore deeper diving, make sure to get appropriate training (i.e. tec), carry a redundant gas supply (i.e. doubles or a large pony) and make sure you have enough gas and the training to deal with any problems that might occur.

 

[WarrenZ]

Since you are asking questions such as this and have been on a few dives I think that you have your eyes opened enough for PADI Advanced Open water class (AOW) The AOW Class is not a bad class and the information is a good start especially since you have seen a few dives. I think that I waited too long do do my OW Class (~30 dives) by that time I was in the class I had seen and done most of the AOW Class in the wild. I'm lucky to have had a few good buddies to have dove with early on.

The best thing you can hope to do at this time is to ask yourself if you are ready to learn more and what direction you want to go with your diving. If that means going on to the PADI AOW Class, SDI Advanced Diver or with a few more dives even an intro to tec diving class I think you will find that whatever you decide there is always something to continue learning.

 

[Rhone Man]

If you have a nominal Surface Consumption Rate (SCR) of 15 liters/min or better, then you are ready to matriculate to Adv Open Water, Nitrox and Intro to Tech for starters. At 15 liters/min, your depth gauge in meters will indicate how much in bar you will consume in 5min (for a single 11 L/bar [AL80] stage cylinder) or in 10min (double 11L/bar for a total cylinder rating of 22L/bar). So for example, at 30m depth you will consume 30 bar of gas in 5min on a single 11L tank, or 30 bar in 10min on a manifolded twinset of 11L tanks. This is IMHO/IME is the easy base reference SCR for a warm water deep/tech diver in Gas Consumption Planning & Deco Profiling, both Pre-Dive and on-the-fly real time.

Kev, just out of interest - has there ever been a thread on Scubaboard that you didn't reply to by opening up with a discussion on gas consumption rates?