Average Gas Consumption

[scubadada]

Is there any way to track the changes, it would be interesting to see the correlation between experience and RMV develop over time in a large population.

Hi @arew+4

The information to do such an analysis was not captured. Several divers have reported their personal experience. Perhaps others will too.

I did not start calculating my RMV until I had nearly 450 dives in a variety of environments. Since then, my RMV has decreased only very slightly. The variation, as reflected by the standard deviation, has also decreased very slightly. The analysis is a good example of statistical significance without practical importance.

 

[MT_Shadow]

Pretty interesting read through this. Like most people in here posted I, as an average diver, have no clue what my RMV is.... I am switching to sidemount this spring and will move from my petrel to my perdix so it will be interesting to see what mine is. I have not dove AI before. I just know my wife comes back to the boat with more gas left over than me 99% of the time and we both have more gas than the other divers on the average boat dive from a resort in Mexico...

 

[scubadada]

Pretty interesting read through this. Like most people in here posted I, as an average diver, have no clue what my RMV is.... I am switching to sidemount this spring and will move from my petrel to my perdix so it will be interesting to see what mine is. I have not dove AI before. I just know my wife comes back to the boat with more gas left over than me 99% of the time and we both have more gas than the other divers on the average boat dive from a resort in Mexico...

It would be interesting to see what your RMV is in your current configuration, I assume single back mount, and then compare it to your RMV when you switch to sidemount. It will also be interesting to see how your RMV changes with your experience using sidemount.

 

[inquis]

I, as an average diver, have no clue what my RMV is.... [...] I have not dove AI before.

You don't need AI to know your RMV. All you need is the gas used, time, and average depth. Gas used is easily found from starting & ending pressures and tank size. I'm sure the math is described up-thread, but many dive logging programs do all the math for you if you give it the start/end tank pressures. AI is a nicety, as it can give you an RMV during subsections of the dive.

 

[inquis]

It will also be interesting to see how your RMV changes with your experience using sidemount

+1. I found my RMV increased greatly with a new configuration and training. The subsequent decrease gave me insight into my comfort/anxiety level as more things became automatic.

 

[Dan]

After so many time diving in overseas, I started to use metric system as it’s much easier to see & remember the number on my Teric. It shows my average SAC is about 1 Bar/min. It could go up to as much as 1.2 or as low as 0.8, depending upon finning against the current or just hanging in the shallow (muck diving).

 

[inquis]

I started to use metric system as it’s much easier to see & remember the number on my Teric

Nice rate! I stick with imperial for similar reasons. 10 psi/min is my normal in cold water/doubles/drysuit. If I see an 8.x during the dive, I know I'm especially Zen. Conveniently, 20 psi/min is my normal in warm/AL80/3mm, and 18 is getting good (for me).

 

[Mike1967]

Nice rate!

Wouldn't that depend on the size of his tank?

 

[jborg]

Wouldn't that depend on the size of his tank?

I'm confused, are your warm and cold figures back to front?

Doubles were mentioned for cold water.

 

[inquis]

are your warm and cold figures back to front?

The cold SAC is lower because it's in doubles. RMV works out to 0.6 cuft/min cold+doubles, 0.5 cuft/min warm+single.

Wouldn't that depend on the size of his tank?

True, but based on a full pressure of 205 bar and @Dan's penchant for travel, I'm assuming a single AL80.