Do I Suck Alot O air?

[Rafael]

Practice, practice and relax, you'll do better.

 

[tlawler]

So what would be considered good for an SAC? Less than .50 cu. ft./min? Anything over .60 cu.ft./min would be an ASD (Air Sucking Dog)?

 

[The Kraken]

Many, many, many people misunderstand the significance on the Surface Air Consumption rate.

Everyone CANNOT have the same SAC rate. A SAC rate is predicated upon an individual and that individual's state of physical health and being at a particular time.

The human body requires "X" amount of air to function normally - given other physical parameters such as temperature, humidity, physical exertion and so forth.

No person is an "air sucking dog". The person simply uses the amount of air that is needed to live.

Given, one diver may consume air faster than another, but that does not make that diver an "air sucking dog".

I wear a size 8 shoe. I have a cousin that wears a size 14 shoe. Does that make him a "leather wearing dog"? No. Why? Because it simply takes more leather to cover his big old Hobbit feet!

Consider, if you will, an offensive tackle for a pro football team and a prima ballerina from a dance company. If one were to remove their lungs and compare them side by side, it would be quite evident that one set is significantly larger than the other.

So, it follows that on a normal breath it takes much more air to fill the football player's lungs than it does to fill the ballerina's.

Now if the two of them are diving and using 63 CF tanks, I dare say that the football player isn't going to get nearly as much bottom time as the ballerina, but he is not an "air sucking dog", he's just been breathing normally.

There are factors that contribute to elevated SAC rates, however, the most prevalent one being anxiety associated with being a new diver and exhibiting rapid, nervous and shallow breathing. These things are generally overcome with experience and time.

So when looking a SAC rates expressed numerically, one just can't look at a number and categorize some one as an "air sucking dog".

Where one's SAC rate comes into play most importantly is in dive planning.

One should be aware of one's SAC rate so that on a particular dive one can say, "OK, we're diving at XX feet. Based on our depth, the tanks we're diving and my SAC rate I should get about XX minutes of bottom time from this tank."

Doing this will allow a diver, or divers, to buddy up with a diver of like gas consumption if possible.

I know that this is not always possible, but it does provide a planning method by which divers can maximize the enjoyment of their diving experiences.

. . . just my 2 psi

the K

 

[tlawler]

Where one's SAC rate comes into play most importantly is in dive planning.

One should be aware of one's SAC rate so that on a particular dive one can say, "OK, we're diving at XX feet. Based on our depth, the tanks we're diving and my SAC rate I should get about XX minutes of bottom time from this tank."

Doing this will allow a diver, or divers, to buddy up with a diver of like gas consumption if possible.

I agree absolutely. I've been paired up with insta-buddies on dive boats before who had no idea what a SAC even was, then cause me to end the dive when my air is still up around 1200 psi. They then get an "ASD" designation in my computer dive log when I add notes to it.

I'll admit I never really paid much attention to SAC after I learned to calculate it in AOW. I did the calculation a couple times and always fell right in the .48-.52 cfm range, then promptly forgot about it since my previous computer didn't calculate it. Now I've got a Suunto Cobra and a running log of my SAC over the last 50+ dives. It has been as low as .43 cfm to a high of .61 cfm on a Spiegel Grove dive where there was a pretty good current. I didn't mean my reply to sound like a "I use less air than you...nyeah!" post, although now that I reread it, I guess that's what it sounded like. I just think to be a considerate buddy, we should all be aware of our SAC (among many other factors too) and use it in planning a dive.

 

[Xanthro]

The human body requires "X" amount of air to function normally - given other physical parameters such as temperature, humidity, physical exertion and so forth.

Someone becomes an air sucking dog where that person's air comsumption rate is significantly higher than what is needed.

No person is an "air sucking dog". The person simply uses the amount of air that is needed to live.

Given, one diver may consume air faster than another, but that does not make that diver an "air sucking dog".

Some people consume air way faster than any human would need it. I've dove with people who are literally using 10 (edited accidently put 100) times the air I was. That's an ASD.

I wear a size 8 shoe. I have a cousin that wears a size 14 shoe. Does that make him a "leather wearing dog"? No. Why? Because it simply takes more leather to cover his big old Hobbit feet!

If your cousin could wear a size 8 shoe and instead was walking around in a size 80 shoe, he'd be a LWD.

I'm more than forgiving of newbies and their air consumption. We've all been there. Very few divers start out with 60 minute dives.

The problem is you have some small number of people who have more than 10 dives who simply suck air at amazing rates. Just as no human wears a size 80 shoe, no human has a natural 20 SAC. I don't know if it is being nervous or what the cause, but they inhale air faster than a free flow it seems.

So yes, there are air sucking dogs, though I would not rate the original poster as such.

 

[CBulla]

Hello all
im new to diving
17 dives
ive been diving in about 30 ft deepth
i can get about 65 mins at that deepth
ive been as deep as 60 ft and my consumptin was alot higher
i use a al-80
is this ok for a newbie ??
or am i a ait hog ?
thanks all

Just buy the HOOVER or Eureka Vaccume sticker and put one on your tank and one on your reg....

KIDDING!

Your doin just fine, buddy!!

 

[The Kraken]

Xanthro wrote:
"Someone becomes an air sucking dog where that person's air comsumption rate is significantly higher than what is needed."

And who, may I ask, determines how much air the diver needs?????? The divemaster, his buddy, PADI, NAUI.

If the person is sucking down that amount of air, it's because he needs it. Period.
Now, can the person work at reducing the stress that is causing him to require that much air, or improving his psychological or physical profile such that he can reduce the requirements in the future, yes. But right now, given his state of being, he is using the amount of gas that he NEEDS.

It would probably better suit a diver to take the time to determine the abilities, capabilities and limitations of his buddy and properly plan a dive and understand, to the fullest extent, the profile of the dive. This would allow the diver to understand, before hand, that his dive isn't going to last as long as he would like because his buddy is going to require more breathing gas on the dive than he.

Just my opinion.

the K

 

[Xanthro]

Xanthro wrote:
"Someone becomes an air sucking dog where that person's air comsumption rate is significantly higher than what is needed."

And who, may I ask, determines how much air the diver needs?????? The divemaster, his buddy, PADI, NAUI.

I determine if the person is going to dive with me again. Nobody needs to exhale every second. Not only does it waste air and hence bottom time, it easily lends to hyperventilation which can be deadly.

If the person is sucking down that amount of air, it's because he needs it. Period.

Simply untrue. Plenty of people suck in air they do not need. Your analogy is like say a 500lb person NEEDS those 8 whole chickens in one meal. It's not a need, even if it provides comfort.

The diver is obviously USING that much air, but does not NEED. Human physiology is not going to differ that greatly in a person where one needs ten times as much air.

Now, can the person work at reducing the stress that is causing him to require that much air, or improving his psychological or physical profile such that he can reduce the requirements in the future, yes. But right now, given his state of being, he is using the amount of gas that he NEEDS.

Again it's not required. Your point actually supports that. If you can change your psychological profile and reduce the air consumption you do not REQUIRE that air.

State of being is no different that my overweight example. The 500lb person may feel he needs that amount of food, but he does not.

I don't dive with non-newbies who suck down 10 times my air, because they are air hogs, and no, they don't NEED to use that much air.

t would probably better suit a diver to take the time to determine the abilities, capabilities and limitations of his buddy and properly plan a dive and understand, to the fullest extent, the profile of the dive. This would allow the diver to understand, before hand, that his dive isn't going to last as long as he would like because his buddy is going to require more breathing gas on the dive than he.

And that's why buddies get to determine whether or not someone is an air hog. Your buddy is wasting your backup air as well if s/he is sucking it in at an inhuman rate.