Reg seems to breathe harder when looking up?

[slackercruster]

A double hose differes from a single hose in that a single hose reg has two stages and the second stage is in your mouth. With the double hose reg, the whole reg is behind your head by the tank valve and all that's in your mouth is a mouth piece.

Since there is a distance in a double hose setup from air source in mouth to reg on tank, does this cause more resistance in breathing than a single hose setup?

 

[slackercruster]

Body position in the water has a great bearing on breathing effort!

A simple way to test this is to try it without a regulator.
Use your snorkel instead, in a normal face down position, with no weight belt, so that your chest is not pulled down at all.

Compare that experience to breathing, while you deliberately sink your lungs to the lowest level possible. This will be leaning back and looking up. You will probably need a weight belt to do this, but be sure to keep it low on your hips so you do not restrict your diaphragm. You will have to hold the snorkel with the tip held up out of the water, easiest to do without it attached to your mask.

This test can be done with no snorkel too, but obviously not having a blow hole, you have to lay on your back and keep your lungs at the highest possible point, maybe by holding onto a float if you are negatively buoyant. We often do this when freediving to get a really good breathe-up, without the dead air space of the snorkel.

There is quite a difference!

Of course water pressure is why long snorkels don't work. Breathing is very labored at about 2 feet and you can't breathe at all much past that depth. (Figuring that your chest has about a square foot of area, 144 square inches, and there is about a 1/2 psi change in pressure per foot... it feels about like there is an extra 144 lbs sitting on your chest while you breathe at 2 feet!)

Regulators are designed to work best when in a normal horizontal position, where the divers chest is close to level with the second stage. On your back, while tilted back and looking up, there is about one foot of water pressure difference. (About like an extra 72 lbs on your chest that your regulator is trying to overcome.)

There are many air flow characteristics that will make a noticeable difference with various second stages, such as internal volume, diaphragm position, breathing tube volume and placement, and venturi devices. If on your back or looking up at great depth, the density of air can also aggravate these regulators ability to perform.

No regulator can breathe equally well for a diver with his chest level well below the second stage, as it does when at the same level.

The trouble here is in the measuring.

Chad

FL Zeagle Rep.

Very interesting, will give it a try

 

[Santa]

Just to add to the fun:

I recently changed a longer and more slender reg hose back to a fatter and shorter one. Unexpected bonus: My reg breathes easier.

Do many of you guys spend extended periods of time diving on your back then?

 

[plot]

Do many of you guys spend extended periods of time diving on your back then?

I don't, but an easier breathing reg seems to make all the difference when clearing my mask.

My pool sessions were done with an Aqualung Titan and it took me a while to realize that everytime I looked up to clear my mask, my reg was harder to breath one which screwed me all up. As soon as I figured out I had to compensate for that reg being harder to breath while looking up, I didn't have any problems. I went onto an Aqualung Legend since then, and havn't had any issues at all... it breaths a whole lot easier when looking up.

 

[Santa]

In most mags when they test regs there's an "ease of breathing" type category. Apparently the new flagship atomic tests really well on that score both o.w. and in the lab. So does the new Oceanic.

I've of course noted differences myself on different regs - and it's always nice to have a good breathe sure - but to me never seemed as essential to me as relaxing and keeping up slow and steady breathing patterns.

But I don't know - maybe some of the regs out there are especially tough? If you can hardly breathe when mask clearing or performing other minor tasks it sounds like somethings wrong with it.

 

[plot]

In most mags when they test regs there's an "ease of breathing" type category. Apparently the new flagship atomic tests really well on that score both o.w. and in the lab. So does the new Oceanic.

I've of course noted differences myself on different regs - and it's always nice to have a good breathe sure - but to me never seemed as essential to me as relaxing and keeping up slow and steady breathing patterns.

But I don't know - maybe some of the regs out there are especially tough? If you can hardly breathe when mask clearing or performing other minor tasks it sounds like somethings wrong with it.

It's not being able to hardly breath, it's the regulator being significantly harder to breath when looking up compared to looking forward or down. If you fail to realize this and fail to compensate for this, then minor tasks like clearing your mask can become somewhat difficult.

In the pool we went from looking forward to looking up and clearing. Eventually when my mask was already clear I just happened to look up and notice it was harder to breath.

 

[Santa]

I guess with regs, to a certain extent, you get what you pay for. There's definítely some makes out there that go a long way towards eliminating that inconvenience. If you've got a model with more resistance there's probably not much to do about it. It's pretty commonplace.

One thing though- I don't know if this applies to all regs but: On my oceanic - if I remove the hose from the second stage - there's a small plastic screw inside that regulates breathing resistance.

Of course increasing the airflow makes the reg more prone to freeflow and depending on experience you may also find yourself going through the bars a bit faster.

I don't think this will really change the mechanic that makes it breathe harder but maybe it will loosen up a bit. You can get your LDS to do it if you're don't like to meddle with it yourself.

 

[plot]

I was using an Aqualung Titan when I had that problem. I switched to an Aqualung Legend and it doesn't have that issue at all... breaths very easily. I'm completely satisified with spending the extra money on it.

 

[Web Monkey]

Actually think my Atomic Z1 breathes easier when I'm upside down,,,,could this really be!?!

Not unless it was violating several laws of physics, or needed service badly.

Terry

 

[meesier42]

Reg seems to breathe harder when looking up? Is this normal?

Yes this is normal for all regulators, When you are looking up you mouth (and therefore the 2nd stage diaghram) is at a lower water pressure than you lungs.

That means that you lungs have to overcome this additional pressure to overcome this differential. Since it is less than a foot this pressure difference is small and not a problem.