Question Air Hog

[Open Ocean Diver]

I agree 100%! I decouple my breathing from my consciousness and use it to maintain depth stability and maximize neutral float. I probably make small adjustments to my BC air at least 30 times during a dive.

Please explain… if we’re using are lungs and not BC for buoyancy control what’s the problem?

 

[Open Ocean Diver]

Women sip air and don't even breathe as far as I can tell. They probably don't need to since they aren't able to nag at or discuss how idiotic men are when underwater. Air is of no use to them below the surface...

To ensure my wife always has less gas than me I have 2 AL 80s and 2 HP steel 80s for her. I have 2 hp steel 100s and 1 HP 119 (looking for a 2nd). I also always have a pony with me. I let her gas dictate our dive planning and turn points. There is no way I'll match her lack of breathing so I compensate by bringing more with me.

My wife is fearless in the water and I think by natural selection she devolved gills. Lol

 

[OMyMyOHellYes]

My trim is good, I don’t use my BC except on the surface. I need to practise your breathing technique. When I do the deep breathes and exhales my buoyancy varys quite a bit. I’m not sure what I’m doing wrong. Looking at some of my profiles I see a lot of zigzagging.

I don't do deep breaths with every respiratory cycle. Unless I need to come up a little.

I'm probably doing it wrong, but it works for me for buoyancy control and has extended my typical endurance from being the first one topside with minimal marginal reserve to being the last one up with a surplus reserve.

I kinda want to be using about 50% lung capacity for breathing (breathing the "top half" of my lungs). That gives me room to inhale if I need to come up or exhale and breathe more shallowly if I want to go down. I also don't immediately cycle between inhale and exhale cycles (I did that for my first several dives). Slow inhale/exhale cycles with a pause between. Every so often I have to refresh and exhale all of it and start with a new batch of air. Probably why I like a second stage that doesn't want to push air into my mouth. I want to have to pull a little tiny bit to crack it open. I sometimes find myself "tongueing" (a term picked up being a low brass player in my long-ago formative years) to control the inward flow of air after exhalation when descending...

OMMOHY

 

[BlueTrin]

If you happen to have an AI computer that displays the SAC in real time, I found it incredibly useful to improve my SAC rate and test breathing techniques.

What works for me (and I don’t have a low sac rate like some people here) is to sip the air slowly like if it was through a straw, pause and exhale slowly. It’s a bit similar from the relaxed breathing if you were trying to calm yourself down with eyes closed by breathing slowly in and out.

 

[NW Dive Dawg]

My wife and I are both very experienced, but she is female and I am not. Our solution to "finishing together" is she uses a 63 and I use an 80. That is, she uses a smaller tank -- which she likes because it is easier on her back -- and I use a "standard" tank. Most dive ops support 63s and 80s.

My wife and I do this also......but mainly on Bonaire for shore diving as the 63 is a lot easier for her to handle when hauling gear to the shoreline.... On boats we usually dive AL80's unless there is a larger tank option for me..

For general air consumption I would tell students to simply try a slow count to 5 while inhaling then a slight pause then a slow count to 5 while exhaling...... just that alone will usually substantially increase a new divers consumption rate...and eventually becomes automatic.

 

[scrane]

Please explain… if we’re using are lungs and not BC for buoyancy control what’s the problem?

You are using lungs to fine tune your buoyancy control. You are using your BC to set a buoyancy level where an intake of breath will make you rise and an exhale will make you descend. There is hysteresis involved so the timing and volume of your breathing will allow you to maintain a steady depth. For me this moderation (modulation?) of volume and frequency translates as low air consumption. My target for the volume of air in my BC is to achieve perfectly neutral buoyancy with my lungs half full. As my depth over the course of the dive changes so will the volume of air in my BC. Thus the frequent minor adjustments via the inflator (or dump). This will continue to the point where ideally I have 500 psi in my tank at my safety stop of ~15' with zero air in my BC due to my proper weighting.

No matter what, you will be at least 4 lbs heavier at the start of your dive than you will be at the end. If you do not utilize your BC you will be fighting this buoyancy delta somewhere in your dive.

 

[Open Ocean Diver]

So you’re saying use my BC for what it is intended for, and in order to use more of my BC and less of my lungs I should add some weights In order to achieve neutral buoyancy? to archive say hovering in place.

 

[hammet]

Get a dive computer that displays your SAC rate.

 

[Open Ocean Diver]

Get a dive computer that displays your SAC rate.

Previous post:

Checked my dive log on my cobalt, my gas usages is all over the place.

I see one 85’, 37min dive, surfaced with 591 psi, gas use .60cfm. - This is a vacation dive usually much more relaxed.

Another 98’, 24min dive, surfaced with 614psi, gas use .88cfm. - Diving here at home off a boat seems to be more tense and rushed

 

[hammet]

A DC that can display your actual air consumption rate while you dive will immediately tell you if you’re breathing too fast. Then you can make a conscious effort to slow your breathing and physical exertion to some target rate. I find it invaluable.