Gas Management With Sidemount

[Kevrumbo]

This is important!

Reading this thread, it's less about gas management and mostly about gas balancing. I'm with Bob. What ever you decide on, make it consistent.

I like to keep tanks within 300 PSI. I breathe one tank down 300 psi or to when it's a multiple of 300 and then start the back and forth. Say my tanks are at 3500. The left gets hit first down to 3300, then I breathe the right to 3000, the left then down to 2700 and so on. I use two Hollis DG03 with transmitters. Each has the transmitter on that side as the primary gas and the one on the other side as the second gas. I use rechargeable batteries in the transmitters and they get changed out every other dive. The only errors that I've encountered have been human induced.

Switch your AI to Metric Pete . . .dare ya to try it! You will be wondering why you wasted money on that AI/Tx gimmick battery instrumentation instead of using reliable mechanical analog Bar SPG's.

 

[The Chairman]

It doesn't matter what measurement system I use: I still need to know how much gas I have in my tanks. It doesn't matter if I'm doing this in psi or bar. Hey, I know you've got this fixation on the metric system. Good for you. I dive my eCCR in metric and my other stuff in imperial. I simply don't have a problem switching back and forth.

 

[PhatD1ver]

If you can tell, why have a protocol dependent on time or pressure?
Just switch when needed, look at the spg two or three times an hour to be sure.
Dive, don't calculate.

That's a reckless way to dive SM, things happen, you get distracted, over overloaded with other things, or you are below 30m and a little narc'd, that's exactly why there are procedures, drills, and training.

I'm guessing you've never actually run out of air other than in your OW course when they twisted the valve shut. Trust me, the first time you pull a dry breath thru your reg, you'll start trying to remember everything you've ever been taught, and the ONLY thing you will remember is to look for your buddy and give the "throat slash", that's assuming you are diving with a buddy, in which case if you are a 'solo' diver and breathe dry a tank... shame on you.

 

[Patoux01]

I'm guessing you've never actually run out of air other than in your OW course when they twisted the valve shut. .

I dunno, running out of air says more about the one that does it than the one that never did.

I'm with him on that one, switch every 20-30b or whatever, doesn't matter...

 

[PhatD1ver]

I dunno, running out of air says more about the one that does it than the one that never did.

I'm with him on that one, switch every 20-30b or whatever, doesn't matter...

Well, I guess it might, less the facts were known. In one case, it was a new diver, who should have done things different, but didn't "plan" to potentially run out of air, I just did.

I'm not proud of having an OOG emergency, but I learned from it. That's all I can do, I can't put air back in my tank for dive #16. But I can be sure I practice good habits on dive #173 to ensure I surface with air in both tanks.

Far cry from using a gas switching plan that relies on "just diving" or "whatever". And, I can tell you anyone who has been OOG would never use the word "whatever" to go with diving plans.

 

[Patoux01]

Well, we might have a different level of awareness...

 

[PhatD1ver]

true that might be

 

[Razorista]

You are misunderstanding what I am saying @PhatD1ver.

Any rigid system can 'break', not having one cannot.

For example: any routine you might have developed is broken on decent as soon as you add a third tank.

There is no real reason why you should not switch regs several times in any interval you might set, but a lot of reasons to not be able to do a comfortable switch at any one certain point in time (forcing you to postpone it).

Not using rigid intervals reduces the need for exact calculation and the resulting taskload.

 

[Kevrumbo]

You are misunderstanding what I am saying @PhatD1ver.

Any rigid system can 'break', not having one cannot.

For example: any routine you might have developed is broken on decent as soon as you add a third tank.

There is no real reason why you should not switch regs several times in any interval you might set, but a lot of reasons to not be able to do a comfortable switch at any one certain point in time (forcing you to postpone it).

Not using rigid intervals reduces the need for exact calculation and the resulting taskload.

"Affirmation without discipline is the beginning of delusion."
"By failing to prepare, you are preparing to fail. . ."

 

[Razorista]

"By failing to prepare, you are preparing to fail. . ."

Preparing means taking the amount of gas you need for the planned dive profile and any kind of plausible unplanned exertion.
With the right 'preparation' spgs are used to double-check on a status you already know.