mbaker248
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What would be considered a good SAC rate for a diver?
SAC Rates
- Thread starter mbaker248
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... one that you're comfortable with ...
Newer divers tend to worry about having a high SAC rate. You shouldn't ... it drops as you develop better technique and learn how to relax.
When I first started diving, my buddies used to tease me that they could see the sides of my tank moved when I breathed ... now I usually finish with more gas than they do (well, except for TSandM who breathes like a bird).
For someone in your experience range, a SAC rate of 0.6 to 1.0 cubic feet per minute would be about normal, depending on your body size and how much you're exerting yourself as you dive.
If you'd like to learn more about gas consumption, visit my website and read this article ...
... Bob (Grateful Diver)
I would guess that the majority of reasonably experienced divers run between .5 and 1.0 cubic foot per minute -- but it changes with body size, fitness, efficiency in the water, as well as water conditions and what you are doing during the dive. I know mine has, in the past, varied by a factor of TWO just by putting a reel in my hand 
New divers can have substantially higher gas consumption, until they learn to relax, become stable, and get more efficient.
New divers can have substantially higher gas consumption, until they learn to relax, become stable, and get more efficient.
sam1
Contributor
I've seen polls on ScubaBoard that, if I recall correctly, 0.5 cubic feet per minute was about in the middle of reported SACs. But as has been posted, SACs depend on many factors, including experience.
Here is a link to a previous post of mine that shows how my SAC differs between diving wet and dry and over time. http://www.scubaboard.com/forums/basic-scuba-discussions/344311-sac-rates-6.html#post5385111
Here is a link to a previous post of mine that shows how my SAC differs between diving wet and dry and over time. http://www.scubaboard.com/forums/basic-scuba-discussions/344311-sac-rates-6.html#post5385111
desert diver 71
Guest
I just read the article "Understanding gas management" by NWGratefulDiver and learned quite a bit. The next time I dive I'm going to try to calculate my SAC just out of curiosity. Thanks for sharing your knowledge with all of us.
SAC rate is normally calculated considering the total underwater time, max depth and total gas consumption.
If your profile involves a deep dive that ends in a shallow part, your SAC will be very low. If your dive is from the start to the end at the same depth (like diving a wreck), the SAC rate will be representative.
My average is 0.61, but I did dives where I had problems with my weight, some others where I was cold, where my SAC was as high as 1.04 and very nice and warm dives where my SAC was 0.47.
I've also calculated a dive where I hit 0.28, but that dive was a deep one at the beginning ending in a shallow reef. I know that this is not a reality, but a trick of the maths involved.
If your profile involves a deep dive that ends in a shallow part, your SAC will be very low. If your dive is from the start to the end at the same depth (like diving a wreck), the SAC rate will be representative.
My average is 0.61, but I did dives where I had problems with my weight, some others where I was cold, where my SAC was as high as 1.04 and very nice and warm dives where my SAC was 0.47.
I've also calculated a dive where I hit 0.28, but that dive was a deep one at the beginning ending in a shallow reef. I know that this is not a reality, but a trick of the maths involved.
elan
Contributor
The one that will give you enough time to enjoy the dive with the tank you use.
LOL I know what you mean. When I did my first boat dive in the ocean (Number 5 lifetime) I did an astounding 60 feet for 14 minutes. LOL now I can grow a beard at 60 feet while I wait on my tank it seems.
Time does make a sac rate better!
roadstarrider
New
It is important to note changing conditions will change you sac rate. Water tempeture is a big one. Unfamiliar gear, real poor vis, current or work load basicly anything that can cause you stress under water can change your sac rate. I tend to try and use a range rather than an exact number. Where I normally dive the water is very cold, I use dry suit, dive with doubles in a lake with generally poor vis my rate is .62 but when I go to there tropics I have a sac rate of .35. So when you are using sac rate to calulate air requirements you need to try and predict what things you may run into on that dive and ajust your calculations.
vladimir
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If you calculate it that way, you render the statistic useless. Use average depth.
Use better math.
I am a fit 6'1", 220 pounds. In the clear tropical water I dive in, my SAC is a fairly consistent .5 cubic feet per minute. That is respectable, I think, but not stellar. It means that if I am diving with another man, we are equally likely to turn the dive, and if I am diving with a woman she will have a half-tank safety margin.
Two weeks ago a buddy ended the dive 40 minutes before me, however, so it does vary quite a bit from one diver to the next.Similar threads
