Twin-hose open-circuit scuba regulators

[Anthony Appleyard]

... There are no sort of bondage straps on the DSV mouthpiece. ...

Strapped-in mouthpieces have their uses. Once in Trearddur Bay with my Nemrod regulator strapped in, I let myself go completely limp to simulate unconsciousness, and while limp the buoyancy rolled me over to belly-up, and my cheeks distended, but my strapped-in mouthpiece stayed in place and watertight.

 

[John C. Ratliff]

Strapped-in mouthpieces have their uses. Once in Trearddur Bay with my Nemrod regulator strapped in, I let myself go completely limp to simulate unconsciousness, and while limp the buoyancy rolled me over to belly-up, and my cheeks distended, but my strapped-in mouthpiece stayed in place and watertight.

On early dives, the divers sometimes used a strap system to keep the mouthpiece in their mouths. It was done on deep, experimental dives. I believe that the Nemrod Snark III mouthpiece had the option of using one of these straps.

Fred Roberts, in his book, Basic Scuba,* used a strap on an experimental dive in a chamber wet tank using a brand new DESCO double hose regulator (never actually commercialized, I believe) to 380 feet on air. This dive was made on May 29, 1955. Fred described this dive in detail over multiple pages in his book (pages 421-427). Here is some of what he wrote:

I took one other precaution. I attached a strap to the mouthpiece to make sure that in case of "blackout" it could not be lost. THe thought of passing out and drowning in the closed tank before they could open the hatch was not pleasant. Later you will note that this was not a wasted effort...

..."I braced for the ascent. As I looked around the chamber I remember thinking 'It's all over now' and mentally patting myself onthe back. I still thought I was somewhere around 360 feet, since that was where I last saw the needle on the depth gauge when I moved to the ladder. THEN THERE WAS NOTHING! The men outside saw that my head was bowed. My muscles twitched violently as I hung onto the ladder. The pressure gauge read 165 pounds per square inch, the last pressure reading recorded by the tape recorder--a pressure equivalent to that experienced at a depth of 380 feet.

"The descent had taken eight and a hulf minutes from the surface and 30 seconds on the bottom for a total dive of 9 minutes duration. I remmmber very little of the many things that went through my mind. I was apparently "out" but I do remember having what seemed to be dreams. At first there was a total blackout. Then a vague sence of consciousness. I would never care to have the feelings of that half-world of unreality again.

"MY BLACKOUT CAME WITH ABSOLUTELY NO WARNING. There was no physical unpleasantness connected with it--I was conscuious one monment, and unconscious the next.

"As I began to wake up I remember two incidents which occurred during my semi-conscious state. The first may have been the factor that resulted in the death of Diving Master Maurcie Fargues, a member of Captain J. Y. Counstea's diving team, who descended to the remarkable depth of 396 feet. This also may havecost a Miami attorney, hope Root, his life on his 400 foot air dive, from which he never returned.

"For some reason, all at once I could not seem to get enough air to breathe. My lungs felt as though they were on fire and I had the urge to open my mouth wide and take deep breaths. Fortunately this sensation apparently did not last too long, and I had fastened my mouthpiece around my head and in my mouth so hard that the corners of mouth were stretched over the edges, and this would not possible allow me to pen my mouth. Finally the sensation was gone and I could breathe easily again.

"The body of Diving Master Maurice Fargus was recovered via a lif line with his mouthpiece hanging at is ches. Perhaps he too felt the urge to open his mouth wide nad found only water to inhale. He died of drowning. No one can say what happened to Root since Sonar lost him at 400 feet in 600 feet of water...

I myself have not had a double hose regulator strapped to my mouth, but we used to do that with single hose regulators, loosely.

John

 

[Nemrod]

Just saying, but strapping regulators into the mouth tightly, single or double, is foolishness of sorts. Other opinions may vary. Not the same as using a necklace for an octopus or secondary at all.

James

 

[AfterDark]

Just saying, but strapping regulators into the mouth tightly, single or double, is foolishness of sorts. Other opinions may vary. Not the same as using a necklace for an octopus or secondary at all.

James

Like everything in diving there are probably situations where a strapping a mouthpiece to one's mouth has advantages. A FFM would probably serve better but everyone has their preferences.

I like regulator necklaces and have used one for decades but that's so the 2nd stage hangs below my chin, a DH is there by design.

 

[John C. Ratliff]

When we jumped parascuba in the U.S. Air Force, we used single hose regulators with neck straps. We didn't want the second stage to get tangled in the risers or suspension lines as we jumped, sometimes being turned and doing sumersaults because of the turbulence of a HC-130's turbo props we were jumping into. Also, on the water, without the neck strap it would be harder to find the second stage, and keep it out of the suspension lines.

SeaRat

 

[Nemrod]

Mr. John, that is a great picture. And that looks like a Calypso?

As to the practice of simulating unconsciousness, I would advise against that lest one become permanently unconscious. Just a thought.

James

 

[John C. Ratliff]

Mr. John, that is a great picture. And that looks like a Calypso?

As to the practice of simulating unconsciousness, I would advise against that lest one become permanently unconscious. Just a thought.

James

James, it is indeed a Calypso regulator. We got them before they were Navy approved, as these were still with the smaller exhaust. The picture of me is from 1975, and the parascuba jump is from 1968. I was in the regular USAF and we jumped into Buckner Bay, Okinawa for that training jump. Later, as I was going to college, I rejoined the USAF Reserves and flew out of Portland, Oregon.

Now, I have simulated unconsciousness, but that was when we were trying to figure out BCDs and whether they would keep a diver face-up. I don't think I've made that simulation for regulators, single or double hose.

John

 

[MrCatDude]

So cool - I've always wanted to try one.

 

[Nemrod]

Many double hose divers learned on double hose. I did and I never quit diving DH until I ran out of parts, hoses and mouthpieces finally perished. When the little cottage industires sprang up supplying parts I was thrilled never dreaming a new, fully modern DH regulator would eventually result. But it did.

But I am going to throw this out there. If you dive double hose, never having used one before, only single hose, you may not like it at all. It is a very different thing. Not just having two hoses but the way they breath, the way the diver has to position himself in the water, the way the equipment has to be postioned on the body, your swimming postion in use, everything is very different and though it is very different it may not be apparently so to the novice DH diver. For example, the center of the diaphragm located in the can MUST be centered to your lungs and this means a very low tank. And as well, the diaphragm needs to be as close to the back as possible which means the regulator must be almost touching the back. The DH diver has to learn to ride the Venturi and make long, slow inhalations letting the Venturi push the air to the diver to reduce WOB and it is helpful sometimes when working hard to swim slightly to one side or the other to bring the diaphram of the regulator closer to the same postion in the water column as the center of the lungs, usually favoring the exhaust side higher.

To the point, if you are going to dive DH you must forget SH and put that out of your mind. Forget it as if SH never existed. You must think in DH terms and live in an alternate (steam punk like) universe. Forget tech plates and STAs, toss the poodle jacket, forget you ever heard anything about DIR and long hoses, you are in a different ocean now the DH ocean !



N

 

[AfterDark]

I daknow James I get by pretty well will a BP, STA and wing with my DH. Course my tank bounces off the back of my knees!! LOL