Basic Training + Planning

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261311

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I was reading in a magazine about technical diving and being able to properly plan dives. Based off of what my PADI OW book states and my actual course (3/5 modules completed), I was wondering- why isn't air consumption and decompression something more focused on? Is it and I'm missing content from a difference of instructors or dive associations? It feels pretty basic in knowledge to be able to plan a dive from beginning to end in a very thorough manner with even just a basic level certification.

Let me elaborate below:

So far from what I'm both reading and being told air consumption and decompression isn't a large focus of just basic open water certification. You learn about staying within NDL and to always keep an eye on your SPG but the magazine I was reading had it right I think. A large separation between rec and tec divers is planning and knowledge. It may just be my anal will to learn and know everything about what I'm doing, especially in dangerous settings but I'd like to be able to plan out a dive and be able to appropriately troubleshoot (ie. reaching into decompression stops) most problems. I know that as a common article OW certified divers aren't supposed to have to worry about decompression if they're being smart and following the dive tables- but would the knowledge ever hurt someone? I'm trying to look at this as more of a planning empowerment situation over one to empower dangerous stupidity in testing boundaries you're not supposed to be inserting yourself into. As far as air consumption goes I think it would be kind of neat to start scuba knowing what your consumption is and to be able to improve it and see progress and at a later point if possible, plan more dives with the same tank air permitting (ie. I go for 30mins at 40ft and consume 1/3 a tank, I'm able to then logically calculate I'm able to safely squeeze in x amount of time at x depth on a single cylinder).

Just a few noob thoughts, not trying to start a certification flame war depending on peoples preferences. *puts on learning cap*
 
In my opinion the knowledge will help some, but hurt others. While I'm on your side of knowing everything you can, some folks may decide that just because they've read a few books that they are safe beyond an NDL, overhead environment etc. I am not saying everyone will do that, but some might. Another reason is that most dive for just fun and expanding their training into technical diving or even just deep diving takes the fun out of it for them. Different strokes for different folks. However, a good understanding about deco theory, physiological changes the body undergo's from diving, basic equipment function and troubleshooting is a good thing, especially when TSHTF. Even if advanced types of diving are not what the person wants to do, a good book and a solid mentor are worth their weight in gold.
 
I actually just went to a PADI member update. They are rolling out a new Open Water program some time this year (or next or the year after). In speaking with some people, it appears that air (gas) consumption will be one of the subject areas that gets added coverage in the new program. I spend extra time on gas consumption in my classes because I feel that it is important. In the pool (starting with "dive 1") I tell them that when I ask for there current tank pressure, I want them to tell me what they think they have. Then we will check it against the gauge to see if they are correct. This let's them learn from the start to check often (which allows them to be right when I ask them) but also understand the consumption rate over time. This is continued into their open water dives with me. All divers taking courses from me at any level get the same deal on consumption.

As far as decompression goes, an open water diver should dive in a manner which you never enter decompression. We teach emergency decompression procedures only because you have to have the tools in case you do blow your dive plan for whatever reason. If you dive conservatively, you will never have to worry about it.

After you get plenty of diving done, you can decide if you want to make the leap to the technical diving "dark side". I will warn you that it is addicting!

Scott
 
There is more to technical diving than the open water class or even an advanced or rescue or deep or navigation or enriched air or ... can teach you. Open Water divers (New or not as experienced) need to focus and hone a lot of individual skills and multiple taskings before they can be ready for technical diving. Tec diving is more than knowing your SAC and ensuring you have enough air for the dive. That is the EASIEST part. It's what to do when the stuff hits the fan and how comfortable you are dealing with those problems that distinguishes a tec diver from an open water diver.


Sent from my iPhone using Tapatalk
 
261311, PADI has trimmed the OW course down to its present format in order to allow students to complete it in as short a time as feasible. The idea is that they teach the minimum required to allow safe OW diving. Sure, theoretically speaking, a course teaching any potentially hazardous endeavor can be made "more safe" by teaching more information, but that requires two (likely related) things: (1) a longer course, and (2) the ability of students to absorb it. With so much to learn crammed into just a few days, most students would not be capable of absorbing the extra material well. A longer course seems to be the opposite of the direction instruction has been heading--you're talking winding the clock back to the way scuba diving was taught decades ago.

You yourself may be interested and capable of absorbing more, but I suspect most OW students are not.
 
IMO there is not enough gas planning in OW. I can't speak for all agencies, but PADI, SSI and the CMAS/FFESSM courses that I have worked with do not really mention it beyond very basic signalling with 'low on air'. One time during the PADI OW video part one, you see a diver signalling 1500psi in a swimming pool. Other than that, it's 'low on air'.

The 'reserve' works reasonably well within OW depths. However too many OW divers are going to the limits (and staying there) as a matter of course, instead of staying within these depth limits. A 'typical' OW diver should be diving between 12-15m and not diving to 18m/60ft as a 'planned depth' IMO.

While I have taught during some OW courses, I don't believe there is a real need to go in to things like SAC or RMV in the basic OW course, but more emphasis on staying shallow and at least a simple guide about 'half tank' and 'reserve'.

Example:
HALF TANK= check dive time; if you breathe half your gas in 24mins, you have another 24mins left until you run out, thus you should think about ascending to a shallower depth pretty soon, if not now.

QUARTER TANK = Reserve. Begin safety stop and surface.

This works pretty well within OW depths- it can start to get sketchy beyond 15-18m/60ft. Thus AOW should have more gas planning involved. IMO Deep should be planned as the last dive, and the preceding 'adventure dives' should be conducted with reference to gas consumption to give the student at least a concept of things like ROCK BOTTOM gas reserves for themselves and their buddy.

Instructors cannot control what a diver does after certification. I tell my students this. I also tell them that I will give them as much knowledge as I can within the time that we have together- whether they choose to learn from it or not is up to them. I do make sure that we log the dives, and ask them to write what they feel they have learnt during an OW/AOW course.

Decompression is covered fairly well in the standard OW course IMO. Ascent speeds are not. PADI still goes for 18m/60ft per minute which is really fast. Breaking that down though, 9m/30ft per 30 secs, and it starts to get interesting at 4.5m/15ft per 15 secs. Thus even at the fastest allowable ascent rate in the recreational diving 'world', it should still take the diver at least 15 seconds to surface after completing a safety stop. Many, many, many divers (including 'pros') ascend much faster than that, and I honestly believe that this is a major, underlying cause of 'undeserved' decompression hits.
 
here we go, we are off and running......this one will take some interesting (and predictable) turns....


edit:

FWIW - It was part of my YMCA OW in the 80's, and part of my PDIC AOW in the early 90's. My wife never saw any of it in her PADI OW in the 90's.....

It appears to be introduced very late now in the education process as it was a "new" learning component in a NAUI MSD program I took last year. I do not know what the NAUI OW or AOW curriculum have as it relates to these topics, but I do know the individuals in the class with me appeared to be learning it for the first time....
 
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I was reading in a magazine about technical diving and being able to properly plan dives. Based off of what my PADI OW book states and my actual course (3/5 modules completed), I was wondering- why isn't air consumption and decompression something more focused on? Is it and I'm missing content from a difference of instructors or dive associations? It feels pretty basic in knowledge to be able to plan a dive from beginning to end in a very thorough manner with even just a basic level certification.

Just a few noob thoughts, not trying to start a certification flame war depending on peoples preferences. *puts on learning cap*

YES, gas management is very important.
No, PADI does not provide enough information on this in its OW course, IMO.
YES, a well rounded experienced instructor will supplement his/her course. You will learn that dive education is about the instructor more so than the agency(s) they teach for.
YES, other agencies such as NASE require a more thorough understand of gas consumption and gas management in their OW classes by making the student calculate SAC rates on every certification dive.

Frankly in all my PADI training through Instructor, I was never really taught this. PADI doesn't introduce this until Tech courses.
Fortunately, I did alot of reading...tons of great info here on ScubaBoard. And good mentors along the way.
 
GUE includes gas planning and decompression planning in their classes from open water on.

PADI is reportedly going to add more about this in their revamp of their OW class for 2014.

Attending a "gas management seminar" given by one of our local instructors (NW Grateful Diver) was the biggest turning point in my diving career. It was at that point that I asked, "What ELSE didn't they tell me?" Turned out there was a lot . . .
 
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