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paulj13
09-12-2007, 21:25
Hi

Was reading an article on scubadiving.com this morning about air consumption (http://www.scubadiving.com/training/basicskills/18_ways_to_use_less_air (http://www.scubadiving.com/training/basicskills/18_ways_to_use_less_air)) and came across the following statement.

“Upgrade Your Gear
Overhaul your regulator on schedule and consider one with lower work of breathing, especially if you often dive deep. ScubaLab tests have shown that the work of breathing demanded by some regs can be three times as much as others, even more. A "hard-breathing" reg not only demands more energy and therefore oxygen just to operate it, your difficulty breathing through it increases your anxiety level and elevates your breathing rate. So it wastes gas two ways.”

‘Lower work of breathing’ or hard breathing’ are terms I’ve never heard of and I was wondering if someone here could in enlighten me as to how to identify it and which regs are rate as which?

It’s a good article you should all have a read of it.

ScubaToys Larry
09-12-2007, 21:52
Sure... Here you go:

http://www.oceanicww.com/img/p_regulators_omega_wob2.gif


The amount of energy your regulator requires to move each liter of air is called work of breathing (WOB). Lower work of breathing equals lower effort required to breathe and increased comfort and safety during a dive.

How to Read Work of Breathing Charts


The computer-generated breathing machine chart presented above represents a regulator's performance per standards established by the U.S. Navy's Experimental Diving Unit. Tests are conducted at 198 feet with approximately 3000-psi supply pressure, 25 breaths per minute of 2.5 liters each.


(1) Inhalation - The chart shows one complete breath cycle, starting with inhalation on the left and continuing along the bottom to the right, staying mostly below 0.0; thus the inhalation work of breathing is reported in negative numbers.
(2) Exhalation - The exhalation effort begins on the right and runs across the top to the left. These are all positive numbers since a diver (or the machine in this case) is blowing out (exhaling) rather than inhaling.
(3) WOB - The total area inside the loop formed by the two lines is what the computer analyzes to calculate the regulator's total work of breathing - the amount of energy the regulator requires to move each liter of air.

thesmoothdome
09-12-2007, 22:00
Well, that answered that question :). Nice explanation. One thing I would add just for clarifcation, is that in many cases this is the difference between a low priced regulator and high priced one. I don't know at what price should expect a great breathing regulator, but more expensive regulators are designed to have low WOBs. In this case, you get what you pay for.

This doesn't mean that inexpensive regulators are bad or require too much effort to breathe comfortably. What it does mean is that top of line regulators are going to require even less effort.

paulj13
09-12-2007, 22:19
Is there anywhere that has info on the Zeagle Flathead XP Regulator in regards to WOB?

ScubaToys Larry
09-12-2007, 22:37
Sure... How about here:

http://zeagle.com/clientuploads/Jim_Fox_Photos/Regulators/ANSTI_Breathing_Loops/Breathing-Loop-Flathead-XP.gif

paulj13
09-12-2007, 23:07
Thanks Larry that's great!

BTW, shouldn't you be sleep right now :-)

ScubaToys Larry
09-12-2007, 23:10
Thanks Larry that's great!

BTW, shouldn't you be sleep right now :-)

Yea... I know.. but the wife is out of town (she's in Italy... I'm here... that's fair!) and I've been working on setting up the new wireless network in my house... so posting is kinda my testing!

paulj13
09-12-2007, 23:14
I hear ya, set up my sister-in-laws wireless network last night, were do the hours go!

Nearly midnight over there now, yes? 2 in the afternoon on the 13th here. I could tell you what happens tomorrow but you'll have to promised to look surprised ;-)

Charlotte Smith
09-12-2007, 23:25
I hear ya, set up my sister-in-laws wireless network last night, were do the hours go!

Nearly midnight over there now, yes? 2 in the afternoon on the 13th here. I could tell you what happens tomorrow but you'll have to promised to look surprised ;-)
LOL!!!:smilie39:

ScubaToys Larry
09-12-2007, 23:28
Yea, it was a kick flying back from Sydney. I landed before I took off!

And yea... 11:30 pm in Dallas.

diversteve
09-13-2007, 01:22
I could tell you what happens tomorrow but you'll have to promised to look surprised ;-)

Yea, it was a kick flying back from Sydney. I landed before I took off!
There's got to be some devious way we can all get rich with that...:smilie39:

mm_dm
09-13-2007, 07:39
I could tell you what happens tomorrow but you'll have to promised to look surprised ;-)

Yea, it was a kick flying back from Sydney. I landed before I took off!
There's got to be some devious way we can all get rich with that...:smilie39:

Like maybe finding out the winning lotto numbers:smilie39::smilie39:

mm_dm
09-13-2007, 07:46
Is there anywhere that has info on the Zeagle Flathead XP Regulator in regards to WOB?

I have XP's. I bought them because of their ability to deliver under pressure (pun intended). Check out WOB on balanced vs unbalanced
regs, you'll start to see some of the differences. If you're strictly a vacation diver, warm water and recreational depths, you can breathe off of most any reg.

creggur
09-13-2007, 08:28
This is one of the reasons I went with Zeagle regulators.

http://i183.photobucket.com/albums/x267/creggur/flatheadxp.jpg

You'll notice in red that the tank pressure is only 705 psi, and in the blue the total WOB is .72 J/L. This is simulated at a depth of 200 fsw.

So essentially you can confidently suck the last breath of air from your tank as easily as the first, at a depth of 200'.:smiley20: I'm joking there of course, but it's good to know the reg will perform that well under extreme conditions..

FXWX
09-13-2007, 20:53
Does everybody know how small an amount of energy a Joule is? It is a watt-second. Compare that to a kilowatt hour that costs about a dime from your power company.

Think of one joule as perhaps carrying a one ounce wieght up a small flight of stairs. Think of to juoles as carrying two one ounce weights up the same stairs. Yes, it is twice the work, but still a small effort.

robjoubert
09-16-2007, 15:48
Hi all,

can anyone tell me where can I find the WOB ratings / info on the Aeris A1 regulator or the Mares R2 Rebel regulator?