What is average surface air consumption?

[Thalassamania]

I'll repeat my answer from the smoking and sac rate thread:

I used to try and get my SAC rate down, then I started getting headaches and decided that the CO2 retention was no good and a bigger tank was a better solution to wanting a longer dive.

My goal now is to keep my normal SAC rate between 0.75 and 1.0. My deco should be cleaner that way and my headaches are a thing of the past.

 

[serambin]

Hold on folks...Let's wait up for the guys who'll say that comparing SAC rates is bogus.

Hey, if you want great SAC rates, get your doctor to prescribe a heart rate reduction drug like Toprol (or another Beta Blocker), or just dive enough to get more relaxed underwater.

Stan

 

[Thalassamania]

OK, comparing SAC rates is bogus. Bed Time!

 

[TSandM]

It's so related to body mass, metabolic rate, and activity level . . . not to mention nerves, buoyancy control, trim and weighting, etc. And a low SAC rate should NOT be a goal, except indirectly as a product of improving one's comfort in the water and one's efficiency. In particular, specific manipulation of breathing rate, or breath-holding, is contraindicated, because they lead to CO2 retention, which has its own hazards, the least of which is headaches.

 

[ClayJar]

Comparing SAC is meaningless, but my SAC numbers at Vortex Spring this Friday made me very happy. I was just swimming in circles with the eels and finding bullets and things in the rocks around 55 feet, plus or minus, and my SAC was consistently under 0.5 cfm.

That said, I didn't check my last dive yet, but I was hanging out at 55' at night -- my lights off, nobody else around, and my back to the cave -- when I felt a tap on my right elbow. My first thought was, "Okay, CJ, calm down, breathe normally...", at least until I turned and had my somewhat relieved second thought, "*Oh*... it's just the eels." They stay away in daylight, but they sure become friendly at night with your lights off.

 

[bertschb]

6' 4", 200lbs

Warm water - .35
NW cold water sight seeing - .45
Cold water while spearfishing off the Barview Jetty with currents, surge and poor vis - .55 or higher if conditions are REALLY bad.

I think comparing SAC rates is kind of interesting. I didn't read this whole thread but when I dive with people (warm water trips) who go through air really fast it's easy to tell why. They are usually constantly moving something. The people who have low SAC rates seem much more relaxed and only move when necessary. I've been on lots of dives with people who are moving their arms, spinning around, changing directions, etc. Sometimes I want to tell them to just chill out. Just cross your arms, hang motionless and chill for a couple minutes.

 

[Azza]

Male
5 10
220 lbs
32 years young
Cold(ish) water
drysuit
Twins or single's

When I was diving 15 times a week my sac was .3 for resting (deco) and .38 for swimming.
Now I am diving 4 times a month it has increased to .38 for resting and .45 for swimming.

For Sudden High Intensity Training (S.H.I.T) it could go as high as .8 or more...

But now I have my own boat it should be dropping again shortly

 

[H2Andy]

For Sudden High Intensity Training (S.H.I.T) it could go as high as .8 or more...

:lol:

 

[Rick Inman]

I've only calculated it once, with dbl 95's, 40cf stage, drysuit, 48f water, swimming a line:

.68

 

[waterbearer]

I figured mine out today. It usually averages between .30 and .35.

I took those averages on deeper dives though. You guys probably don't want to know what the average was calculated on shallower ones.