Air management for beginner.

[Diveral]

I believe in the KISS principle. I have a SCR calculator that I use on my deep dives that I plan my gas management with. I can enter the size of tanks I will be carrying and depths I'll dive and it calculates my available dive time including reserve air for ascents. It will also give me a minimum tank size based on a planned profile. Comes in very useful for my penetration dives but is somewhat complicated.

My default plan and the one I use most often is to dive the rule of thirds. I've never had an issue with air every time I've dove using the rule of thirds. The OOA's or near OOA's I've experienced have occurred when I deliberately push past those limits and run into an unexpected difficulty. I also don't like coming aboard a boat with more than 300#. I've wasted some underwater time if that happens. So if I'm aboard or ashore with more than that either the dive was really boring or there was an artificial limit applied or a situation such as sharks, current, lighting, waves, or buddy where I needed an extra safety margin.

So my downward/outward leg will use 1/3 of my air. Then I turn my dive and return to my start point. Now if everything has gone right like it does 80% of the time I have 1/3 of my air left. Which is 1000 psi for an AL-80. Also since I generally swim into currents on the outward leg I usually get back with 1200-1500 psi left. I don''t need that much for most of my ascents unless I'm doing deco and I'm usually the lowest on air with the guys I normally buddy with (I'm generally the oldest and biggest) so my buddies normally have more air than I. So we hang around the anchor line or exit point for a while and then come on up. I'll usually spend more time on a deep stop and the 15' stop to exhaust extra gas unless there's a reason to keep a bigger reserve.

AL

 

[lamont]

I don't know if it was covered in my OW or not, it was too many years ago. Before you blast me to review my OW class, which I should, how about sharing your opinions.

Assuming a square profile, straight down, and straight up. Not exceeding the no decompression limit (NDL). How much air you would need from 33 ft, 66 ft, and 100 ft.

I am guessing, at 33 ft, for a beginner, you should have about 600 to 700 psi.

At 66 ft, with a 15 ft 3 min safety stop, 800 to 900 psi.

At 100 ft, with a 15 ft 3 min safety stop, 1000 to 1200 psi.

Maybe I'd add an extra 100 psi for current, rough surface enviroment, hazards, etc.

Remind me where in OW did they discuss this.

http://www.scriptkiddie.org/diving/rockbottom.html#thumb

 

[daniel f aleman]

Since when does any agency owe us everything? Take what they offer, and learn the rest somewhere else.

 

[MikeFerrara]

Since when does any agency owe us everything? Take what they offer, and learn the rest somewhere else.

I don't know that the agencies owe anybody anything. They just sell a product. Some consumers will educate themselves enough to decide whether or not that product really meets their needs and some won't. It isn't at all uncommon in sales for a product or the usefulness of a product to be misrepresented. It may not be completely ethical but it isn't uncommon and except for certain extreme cases, it's legal.

When I started diving, my only source of dive information was the local dive shop and the drivel printed in the few dive magazines I saw. I didn't know there was anything else and had to learn (and unlearn) a lot of things the hard way. Other things I didn't learn at all until I got completely out from under the shop and the recreational dive industry as a whole. Starting with the assumption that those who taught you are really expert can be a real barrier to learning. Today, divers have access to a lot more information. I think industry members are getting caught in their fibs and omissions (whether they're intentional or just out of ignorance) more frequently. Some of them are going to have to do some serious catching up just to stay ahead of some of the new people walking in the door. It will do them good.

When an OW student asks about gas management (or any one of a number of topics), the instructor is going to have to come up with some kind of answer. When he/she tells the student that they don't need to know it, the student might ask a more direct question like how are they to know if they will have enough air left to get an OOA buddy to the surface. Maybe the student can point the instructor to Lamonts article or Bobs gas management workshop. the more information students have going in, the better their questions will be and the better the instructor is going to have to be to field those questions.

 

[fisherdvm]

Most agencies don't teach this as part of their OW or even AOW program. When I went though AOW, the most that was said about this subject was "when you dive deep you use more air and it takes you longer to surface, so keep that in mind".
Some people think it is important, others don't. I think that having even a basic understanding of gas management improves safety. If you want more info or training on gas management for rec dives, there are 2 great instructors in your state who do a great job:
Brandon Schwartz
Scot Wernette

I might look them up. Tell me a little more about gue training, and if it will make me a better diver.

 

[MikeFerrara]

You know?...we hear a lot about how dive training has been dummed down. That may be true in regards to swimming requirements, free diving skills and watermenship skills like bailouts or ditch and don. I don't think that's what we're looking at, thoughm when we talk about gas management, how buopyancy control is taught, performing skills midwater ect. These are things that have never been taught. It's new stuff that hasn't been integrated into training yet.

Since Sheck and those guys kicked off accident analysis and came up with things like the rule of thirds for diving overheads, those techniques have been taught to cave divers. This rock bottom stuff is the rule of thirds modified for open water...keeping the idea of having twice the gas needed for the return or ascent.

More and more instructors are learning this stuff and teaching it. More and more instructors are teaching real gas management, buoyancy control and trim from day one and turning out students who can perform all their skills midwater and know how much gas they really need to get back. It isn't main stream yet but eventually someone who knows this stuff might end up working in the head quarters of one of the agencies and have a chance to take a pen to the training standards and student materials.

As these changes slowly progress, old threads on scubaboard are going to get more and more interesting to read.

 

[Jasonmh]

I might look them up. Tell me a little more about gue training, and if it will make me a better diver.

I can tell you that it certainly made me a better diver. Everyone that I personally know who has taken any kind of GUE training thinks that it has made them a better diver. I see you asking questions about things that you seem to feel were lacking, especially in your post saying (in effect) "why wasn't this taught to me?" One of the only agencies I know of who teaches this information at a beginning/fundemental level is GUE. There are many things that are taught in the fundementals class that made me think "after so many classes with other agencies, why am I just hearing this now for the first time?"
My suggestion is to explore it alittle bit, talk to one or more of the instructors, ask them what is covered in the class, then you can decide for yourself if you think it will make you a better diver. Each instructor is different, but I think you will find some good options. Many of them also teach OW/AOW for other agencies, and you might find that they do cover their rec classes with more of a GUE slant, covering things like basic gas management and buddy skills that are not covered in a typical PADI/SSI class.

Good Luck

EDIT - one more thing, there are DIR divers in your area, you could also contact them and get some info/do a few dives. This will also help you figure out if the training might have something to offer you, and it costs nothing.

 

[TSandM]

GUE training made me a better diver, and made my dive buddy a better diver. And, although he was reluctant and resistant, even my husband has come around to the idea that that kind of training can make him a better diver.

 

[Blackwood]

Hmm, see if you can take that OMS wing back. :mooner:

lol. I was picturing a hot air balloon on his back.

 

[Peter Guy]

I'm probably one of the very few who has been trained "the old way" (16 weeks of pool and classroom in 1966); the "new way" (PADI OW, AOW, Rescue and now DM); and the "New, New Way" (Breakthrough Diving's Essentials & Recreational Diving 2 -- not to mention getting hit over the head with GUE dogma from a certain Borg Queen who shall remain nameless). Because of my experience with this spread of teaching, I have the background to make some "profound" statements about the teaching of diving:

1. It ain't rocket science;

2. Diving is, for the most part, pretty darn safe and easy; and

3. Most people learn enough to be pretty darn safe in the environments in which most people dive -- i.e., 5 to 10 days of diving in warm water being led around by a "professional" every year or two.

At least in my limited experience, knowing "gas management" principles, the latest ratio deco theory, deep stops vs. rapid ascents, etc. truly would be knowledge overload for the VAST MAJORITY of "recreational divers."

As far as "gas managment" is concerned, PLEASE, give them an air integrated computer that tells them "You have 'X' minutes of air left" right next to their "You have 'Y' minutes of no-deco time left" -- thus they will get their "gas management" information along with their "deco plan" information. I know this is NOT the Party Line but it does work for the masses -- and thank goodness it does so that I can have access to lots of shops, lots of resorts, lots of different types of cameras with lots of different housings, etc.

Me, I'm a wannabe Techreational diver and having fun at it.

But, please, all you Scuba Boarders, don't look down your noses at the people in this sport who make it possible for me (us) to have our great toys and great trips at "reasonable" prices. Just be thankful the industry and the training agencies, have created the ability for many, many people to learn how to get under the water and blow bubbles pretty darn safely.