Scuba, Hookah, Brownie Alternatives?

[fstbttms]

Originally Posted by wmclibby

Hi,
A simple outfit for "under the boat" work is listed at :

http://www.yandina.com/hints.htm#Compressor

Additionally, Latts and Atts had an article by Kevin Hughes for a "do it yourself" Hookah.

Husky Y1000 Compressor
Two $ 10 50' 300 psi air hoses
2nd stage regulator (example: Oceanic Delta 4)

Never, EVER use an air hose not specifically rated to provide breathing air.

[Rick]

What is a good source for a check valve to be placed at the "second stage" regulator/mouthpiece so that if the hose AT THE SURFACE ruptures that the pressure inside the lungs from the surrounding water does not damage the body should one happen to be holding one's breath. Even at 6 feet of depth this pressure is significant and is not the same as if one held the breath from the surface and went down 6 feet...in that case the surrounding water pressure merely compresses the upper body around the lungs thereby reducing the lung volume.

In the case of inhaling air while at a depth of 6 feet the lungs hold a positive pressure compared to the ruptured hose at a surface pressure of 1 atmosphere and that pressure is against where the airway closes when holding one's breath. If the differential is great enough you damage yourself, maybe causing death..it has happened.

[GordMay]

Originally Posted by Canibul

Just a reminder to anyone building their own, or buying, a hookah. the physics, and physiology, of breathing compressed air is the same whether it comes from a tank on your back or a hose coming from the surface. ..
...Know enough about compressed air diving so that you dont kill, or cripple, yourself. Its really no fun getting bent. No joke. I've done it. Once.

And Canibul (or any other bent diver) will assure us, once is more than enough.

[Canibul]

RICK!! you NEVER hold your breath while diving on compressed air!!!
Sorry Canibul: Unauthorized editorial (emboldened) by Gord May

[Leighton]

Originally Posted by wmclibby

Hi,
A simple outfit for "under the boat" work is listed at :

http://www.yandina.com/hints.htm#Compressor

Additionally, Latts and Atts had an article by Kevin Hughes for a "do it yourself" Hookah.

Husky Y1000 Compressor
Two $ 10 50' 300 psi air hoses
2nd stage regulator (example: Oceanic Delta 4)

Does anyone have a copy of this article they could send me.

Leighton

[wmclibby]

I have a copy and will send it to you as directed. I notice a reply to my posting on the dangers of using a hose at 50'.......The only purpose for this project is to check you bottom, clean it, etc. not to dive to 50'. That would be silly. I need 50' to travel "around" the boat without rearranging the compressor on board.
Cheers,
Bill

wmclibby@yahoo,com

[Canibul]

Well, you wont get into much trouble from nitrogen saturation diving all day at say, 8-10 ft, You still have to remember to NOT lock your airway shut, i.e. holding your breath, when breathing compressed air. Thats a different problem than getting the "Bends" (decompression sickness). Its called embolism, and its from the air in your lungs expanding when surfacing.

Getting bent, it takes a few minutes to start coming on. Enough time to grab another tank, or restart the hookah, and go back down.

Embolism is immediate rupture of aveoli, and you will be coughing blood and drowning in it, and recompressing wont help you.

The whole point is to just know the basics of compressed air diving. I dont think you need a certification card, but you definitely DO need the knowledge.

[GordMay]

Disclaimer: I’m not a certified diver, and haven’t studied the technical aspects of diving in over 40 years.

The greatest physical dangers posed to divers (whether free breath-hold, surface air, or SCUBA) might be summarized:
- insufficient preparation
- bad judgement
- unreliable equipment
- alien abduction
- and lastly but most importantly, ignorance or negligence

Decompression sickness (“the bends”) is one danger of diving. Other dangers include Arterial Gas Embolism, Inert Gas (nitrogen) Narcosis ("rapture of the deep"), Oxygen Toxicity ("Paul Bert effect"), Hypoxia or Anoxia, and simple drowning.

Decompression Illness (DCI) is an umbrella term for both :
Decompression Sickness (DCS)
and
Cerebral Arterial Gas Embolism (CAGE), or just Arterial gas embolism (AGE)

Gas embolism and decompression sickness (DCS) are very difficult to distinguish, as they have very similar symptoms. The treatment for both is the same, because they are both the result of gas bubbles in the body.

Arterial gas embolism (AGE) is a type of pulmonary barotrauma in which bubbles enter the circulation and travel to the brain. Symptoms such as numbness or tingling of the skin, weakness, paralysis or loss of consciousness may occur. This is a serious diving injury.

Decompression sickness ("the bends") occurs during ascent and on the surface of the water. Inert nitrogen gas that is dissolved in body tissues and blood comes out of solution and forms bubbles in the blood. The bubbles can injure various body tissues and block blood vessels. The most common signs of severe decompression sickness are dysfunction of the spinal cord, brain and lungs.

Divers Alert Network (DAN) provides information on decompression illness and other diving related issues.
USA http://www.diversalertnetwork.org/
Europe http://www.daneurope.org/
Asia - Pacific http://www.danseap.org/

Diver Training and certification courses are available from:
Professional Association of Diving Instructors (PADI) http://www.padi.com/english/
National Association of Underwater Instructors (NAUI) http://www.naui.com/

For further information on decompression theory, please refer to the Dive Tables, Dalton's law (gas diffusion) and Boyle's laws.

[Canibul]

I actually used to enjoy the nitrogen narcosis. usually affects me personally around 100-110 ft area. You know about it, you expect it, you work around it. Or at least, I had no choice, I HAD to do the work.

the 'buzz' was just an added benefit.

But for someone who spent a lot of days repetitive diving (installing and servicing bottom mounted tide guages and other oceanographic moorings)and trying to stay right on the no DC limits, it was a familiar thing.

the danger, as I see it, in narcosis is that newbie divers dont expect it, and therefore dont recognize that their judgement is affected and that they need to take that into consideration.

[Rick]

Canibul, Yeah, for the reason that I described you should never hold your breath, and I've been diving for a lot of years and am disciplined to always leave my airway open, even surges under water will change the pressure on your lungs..you can feel it and don't dare close the airway.

Regardless, if diving on a surface lead hose and the hose ruptures at the surface even having your airway open will pose problems on your lungs if there is no checkvalve located at the depth of your lungs. You can't count on getting the mouthpiece on the second stage out of your mouth in time to prevent having all tha air sucked out of your lungs. With a tank on your back the hose can break and the pressure differential is essentially zero so no check valve is needed.

[Canibul]

Havent had a hose rupture on the Brownie. What I DID experience was diving with my wife and son (his first compressed air dive) and at about 30 ft. the engine stopped dead. Man, talk about a sudden strange feeling. There was NO air to be sucked out of that hose. I was watching wife and son...ready to start signalling and worried sh1tlist, but I guess I had drummed it into them pretty well. No panic. We all three just slowly went up, and I watched them both streaming a few bubbles out.

Problem worked out to be shorted kill switch. Fixed it with RTV silicone.

[Rick]

I agree that a catastrophic cut in the airhose at the surface is unlikely yet if it DID happen one would be in a world of hurt. Don't the commercial hookah rigs all have check valves in order to avoid potential liability issues? I know that if I was a manufacturer there would be one.

[Canibul]

I am not so sure that it would suck the air out of your lungs. The second stage regulator itself is a checkvalve, for one. Also, the ID of the hose is pretty small.

If I go to 50 ft and take a deep breath and remove the reg from my mouth and open it and exhale, it doesnt rush out under pressure. Blowing bubble rings with booties while hanging on decomp stops doesnt squeeze my lungs flat.

I think whats going on is that by the time the air gets to you, its at ambient pressure, no matter where it came from tank or compressor.

I seem to recall a little experiment I did when I was six or seven years old. I tied a rock to my waist, put the end of a garden hose in my mouth, and jumped into 12 ft. of water at a swimming pool. I only did that once.

[Fishspearit]

Rick, the valve on the second stage regulator will only open if the pressure in your lungs is less than the surrounding water pressure. A rupture in the upstream hose will only make you lose your air source. The spring loaded valve in the second stage will stay shut. Just like when you exhale.

[Canibul]

yeah, thats kinda what I was trying to say, I guess.

Whew, now I dont have to have someone disconnect the top of my hookah hose to experiment.