Air management for beginner.

[ClayJar]

Considering the number of ScubaBoard members ... from Instructor to not-yet-certified ... who have contacted me requesting the gas management handout I use with my seminar, I would have to disagree with this statement.

Sorry about that; I was imprecise. To state it better, most of the local recreational divers I personally know have been apathetic at best when gas management has been talked about. One expressed a desire to learn more. Several explicitly stated that they don't think they needed to know and didn't care to hear otherwise. I suppose the rest could be considered as not yet enlightened as to why it matters, likely due to it being a first exposure, and that an unofficial one. (Things that are drilled and things coming from instructors tend to be better received, at least at first, but that could be a local cultural thing.)

Divers on ScubaBoard and divers I've met on dives worked out through ScubaBoard have generally been *significantly* more receptive. Perhaps the apathy and antipathy I've observed are a distinctive characteristic of the class of divers living in or near Baton Rouge, or maybe we just have the privilege on ScubaBoard and in some regions to have better than normal divers.

However you slice it, and whyever my local divers are behind the curve, exposing divers to at least a distilled table form of gas planning would likely be a workable first step. (I'll have to try it out on a co-worker who is in the process of being certified. )

 

[ArcticDiver]

Now that I've read the remaining posts I see others think the same way I do.

There is a gap between what a person should ideally do and what is reasonable for them to actually do. Ideally a person should eat nutritious food, exercise daily and do other fine things. But there is a gap between that and what is actually feasible and acceptable for most people. While not exactly the same there is a similar gap in gas management.

I've got Bob's material and think it is wonderful. It is very similar to the GUE and NACD material. I think every serious diver ought to be able to do these calculations.

But, most divers aren't "serious divers" in this context. Nor, are most dives "serious dives" in this context. In steps the home made tables, air integrated computer, or dive guide to fill the gap.

More serious, in my opinion, is the criminal lack of training on what to do if the diver is low on gas, or out of gas. The perfect example of this lack of skill integration happened on my Oahu trip. I'm diving doubles and have lots of gas; on this dive an entire extra AL80 worth. The guy just below me on the ascent line at 90' was low on air. Instead of somehow getting my gas he bolts for the surface. Now THAT is a criminal lack of training and evaluation on his instructor's part.

 

[Soggy]

My point is that the beginning diver doesn't have the data to do a good job of gas management according to the methods more advanced people use. Certainly they could use some really, really conservative numbers to do the planning. But, that is not realistic since that method would result in very short dives compared to others they are diving with. Peer pressure and the dive master/guide reaction will put a lot of pressure on the diver to do it differently.

This is so incredibly bassackwards that I don't even know how to respond.

Coming up with reasonably conservative numbers is not as hard as you might think. The only variable is SAC rate. 1 cfm per diver is sufficiently conservative for safety and also sufficiently liberal to allow for reasonable length dives. It also makes the math trivially easy. This isn't rocket science and I think it is criminal that it isn't taught in open water classes.

I have only dived with a DM once and that was a year after I was certified and had 70 dives under my belt and he sure as heck wasn't going to plan my dive *for* me. Holy trust me, Batman.

Divers need to know how to plan their own dives. Period.

 

[jeckyll]

ArcticDiver: I read a great post by Dan Mackay on another board in which he mentioned the "incident funnel'. He described a funnel where the sides got deeper the further you got into it, until you get to the point of no return.

The earlier in the 'funnel' you get the issue solved, the easier it is to prevent serious problems. I would think that gas planning is at the absolute edge of the funnel. So many issues can be prevented early just with planning.

If you got gas, everything else is a nuisance. Several people on this board have said it.

If you teach "Plan you dive and Dive your plan" but don't teach a key piece, that may not be negligence, but i probably should be...

 

[Soggy]

There is a gap between what a person should ideally do and what is reasonable for them to actually do. Ideally a person should eat nutritious food, exercise daily and do other fine things. But there is a gap between that and what is actually feasible and acceptable for most people. While not exactly the same there is a similar gap in gas management.

This isn't calculus with differential equations. We're talking about knowing how much gas you need to reach the surface with a buddy who might be out of gas. For recreational depths it is incredibly simple to figure out and once you figure it out for each 10ft increment, you can write it down and never have to figure it out again. If someone is incapable or unwilling to take the time to figure that out, they quite frankly should take up another sport because safe diving is obviously beyond their capabilities.

 

[Steve50]

More serious, in my opinion, is the criminal lack of training on what to do if the diver is low on gas, or out of gas. The perfect example of this lack of skill integration happened on my Oahu trip. I'm diving doubles and have lots of gas; on this dive an entire extra AL80 worth. The guy just below me on the ascent line at 90' was low on air. Instead of somehow getting my gas he bolts for the surface. Now THAT is a criminal lack of training and evaluation on his instructor's part.

Unless you were his instructor or observed him taking his instruction, why would you assume he was not trained in air sharing . Panic!!

 

[ArcticDiver]

...Coming up with reasonably conservative numbers is not as hard as you might think. The only variable is SAC rate. 1 cfm per diver is sufficiently conservative for safety and also sufficiently liberal to allow for reasonable length dives...

Come on, think outside your box. I've dived with several new divers whose SAC rate was twice or thrice what you mention. I mean use an entire AL80 in 30 minutes. Also, for many they don't have enough knowledge to adjust on the fly for variable dive conditions that are encountered on the dive.

No, 1cfm planning factor isn't a panacea for the new diver.

 

[PerroneFord]

Soggy,

You know the old 100psi for every 10ft rule darn near ought to get it done for single tank diving. Anyone who can't remember something THAT simple, ought not hold a card. If they start to run low, they'll be at 20 or 30ft instead of 80. And that's liveable.

 

[lamont]

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.

But what about just teaching recreational warm water divers that when they hit psi of 10 x their depth + 300 they should turn the dive? That'd help keep a lot of those warm water vacation divers a lot safer since if they follow it, they won't find themselves at 100 fsw on an Al80 with 800 psi of gas left while they're swimming for an upline. They don't need to know ratio deco. I don't ever care if they know the math behind the rule of thumb. But bumping up the standard a little bit more than 'back on the boat with 500 psi' would seem to avoid a lot of the OOA stories that get posted on this board....

I also don't think AI computers tell you how much gas you need to get back on the boat assuming your buddy goes OOA on you and starts breathing heavy...

 

[daniel f aleman]

This isn't calculus with differential equations. We're talking about knowing how much gas you need to reach the surface with a buddy who might be out of gas.

If someone is incapable or unwilling to take the time to figure that out, they quite frankly should take up another sport because safe diving is obviously beyond their capabilities.

Obviously, millions of safe dives are made, world-wide, by divers who have no clue of gas management.

Explain.