Air Consumption

[HKGuns]

Curious what the thoughts are here on what is a good air consumption rate and what is terrible? I realize there are probably ranges, I see discussion on air consumption in many of the threads here, so am wondering, what are the numbers?

Above Average - <?
Average - ?
Below Average - >?

I now see it matters, so lets say a healthy, average size man on a relatively stress free, warm water dive in good visibility is the baseline for the person and conditions.

 

[Fastmarc]

Obviously the lower the RMV the better, but that varies from person to person, gender, size, physical condition, dive experience, comfort while diving and the list goes on and on, so comparing yours with someone else really doesn't make much sense.
It's better to get a baseline for yourself and monitor it as you gain experience. It will be a good barometer for your progress as you gain comfort and efficiency.

 

[yle]

Might be useful to replace "good" and "horrible" with "above average" and "below average".

Also, the answer to your question really depends on the size of the person and the conditions of the dive. You can standardize conditions as "a no-stress, relaxing dive" to use as a baseline. Any kind of stress (temperature, visibility, current, etc) could be expected to increase the rate of air consumption from that reference.

As for size of person... a "way above average" rate for a 6'2" 220 lb guy would likely be just an average (or possibly below) rate for a 5'2" 115 lb female. Size matters.

 

[Marie13]

Cold water divers will possibly have higher air consumption than warm water divers.

I’ve had warm water divers express surprise at my RMV, but it is what it is.

 

[yle]

But... to answer your question with my own personal experience: I'm a guy, 5'7" 170 lb and when I started diving my RMV was probably around 1.0 cu ft/min.Following years of experience, my RMV now is consistently between 0.36 and 0.40 (and hasn't dropped in several years; I think I've bottomed out.) Conditions don't affect it much, a consequence of experience.

To put that number in perspective, it means at 100 feet I would breathe an aluminum 80 from 3000 psi down to 1000 psi in about 32 minutes.

 

[HKGuns]

But... to answer your question with my own personal experience: I'm a guy, 5'7" 170 lb and when I started diving my RMV was probably around 1.0 cu ft/min.Following years of experience, my RMV now is consistently between 0.36 and 0.40 (and hasn't dropped in several years; I think I've bottomed out.) Conditions don't affect it much, a consequence of experience.

To put that number in perspective, it means at 100 feet I would breathe an aluminum 80 from 3000 psi down to 1000 psi in about 32 minutes.

Thanks this helps. As a new diver, mine is running between .73 and 1.0 with the 1.0 at depth for the first time in 42 degree water. I appear to be within the bell curve for my level of experience. Right?

 

[KatieMac]

But... to answer your question with my own personal experience: I'm a guy, 5'7" 170 lb and when I started diving my RMV was probably around 1.0 cu ft/min.Following years of experience, my RMV now is consistently between 0.36 and 0.40 (and hasn't dropped in several years; I think I've bottomed out.) Conditions don't affect it much, a consequence of experience.

To put that number in perspective, it means at 100 feet I would breathe an aluminum 80 from 3000 psi down to 1000 psi in about 32 minutes.

Wow, that's amazing. I'm 5'2" and 120 lbs and have RMV of .30 to .35 usually.

 

[Bob DBF]

Depends on who you are and what you are doing.

As a new diver, mine is running between .73 and 1.0 with the 1.0 at depth for the first time in 42 degree water. I appear to be within the bell curve for my level of experience. Right?

No worries. Work on other things, the air consumption will sort itself out.


Bob

 

[Outbound]

Thanks this helps. As a new diver, mine is running between .73 and 1.0 with the 1.0 at depth for the first time in 42 degree water. I appear to be within the bell curve for my level of experience. Right?

Water temp will usually affect most people’s SAC/RMV. First off, the cold water alone will do the trick, plus you will be in a thicker exposure suit with more ballast weight. I’d say you are probably on the high side, but certainly not at the extreme end of the bell curve. But don’t worry about it. As long as you don’t run out of air, you are fine. Some people don’t use as much air as others, and just about everyone’s RMV will improve with experience. When I started I was at about a 0.6, and that was in tropical water. Now I’m down to about 0.35 in warm water and about 0.45 in cold water. I’m 5’10” and 160 lbs. for reference. I dive with a guy who is a lot bigger than I am and he uses more air. I also dive with a woman who is smaller and she sips her air like a bird.

 

[HKGuns]

So there is no confusion, I'm not really worried about it, just curious to understand it better and the variables involved. The discussion so far has taught me stuff I didn't know. I have a ways to go before I am comfortable diving, that is my focus.