Hookah Diving

[Skylark]

If it's just for using in emergencies to clear the prop etc you could use one of these:

http://www.amazon.co.uk/Spare-Emerg...W85U/ref=sr_1_1?ie=UTF8&qid=1328173343&sr=8-1

There was one for sale on here a while back for £85 iirc

Donn't hold your breath out on the way up...

Back of the proverbial fag packet calculations and assumptions.

The cylinder has a water capacity of approx 0.5 litre.
Pumped to 200 bar (to keep the calculations simple).
Content therefore 100 litres.
Assume at surface breathing rate of 25 l/min
Consumed in 4 minutes at surface
Say, at 10m, absolute pressure is 2.0 bar, content consumed in 2 minutes.
Say, become a bit stressed underwater or significant change in work rate, assume breathing rate doubles. At 10m, content gone in 1 minute.

IMHO. Not for me.

I've been a diver for 20+ years, more than 1000 dives. Actively involved with BSAC. Please take my advice, don't play with this gear. Get some training. It ain't rocket science but it does have the potential to harm you.

 

[flipper]

Back of the proverbial fag packet calculations and assumptions.

The cylinder has a water capacity of approx 0.5 litre.
Pumped to 200 bar (to keep the calculations simple).
Content therefore 100 litres.
Assume at surface breathing rate of 25 l/min
Consumed in 4 minutes at surface
Say, at 10m, absolute pressure is 2.0 bar, content consumed in 2 minutes.
Say, become a bit stressed underwater or significant change in work rate, assume breathing rate doubles. At 10m, content gone in 1 minute.

IMHO. Not for me.

I've been a diver for 20+ years, more than 1000 dives. Actively involved with BSAC. Please take my advice, don't play with this gear. Get some training. It ain't rocket science but it does have the potential to harm you.

I am not suggesting that using compressed air is without danger but let's not get this out of perspective. I don't see an issue in using the 'spare air' for clearing a prop on a yacht. If he goes 10m down to do it though I would suggest he has a bigger boat than he is letting on

(also been diving for 20+ years, both BSAC and commercial)

 

[fishermantwo]

I'm more interested in something that can be used in emergencies - fouled propellor or rudder for instance. Routine maintenance I can do by drying out. I carry a wet suit and snorkelling gear haven't got much room for SCUBA gear, compressors etc.

Snuba

 

[V1701]

I am not suggesting that using compressed air is without danger but let's not get this out of perspective. I don't see an issue in using the 'spare air' for clearing a prop on a yacht. If he goes 10m down to do it though I would suggest he has a bigger boat than he is letting on

(also been diving for 20+ years, both BSAC and commercial)

I'm totally against unnecessary bureaucracy, etc., etc., but you really should know better than advising someone to go down and clean his prop with a spare air and remember to breathe out on the way up...

 

[fishermantwo]

I built a fully working system along similar lines several years ago (even held a patent briefly - but no commercial interest at the time). The big trick is to have an air bladder (I actually use the liner out of a 3 litre wine box!) in a box (which has holes to allow expansion/contractin) strapped to your back. You draw air from the bladder (which is at the same pressure as your lungs) through a non-return valve (readily obtainable from chandleries - intended for water but work fine for air) to a simple mouthpiece and expelled air goes out via another non-return valve. In my system, the pump is installed in a float (a 5 litre fuel tank), draws air in through a snorkel and pumps it at a constant rate down through a relatively small diameter, 5 meter plastic tube to the bladder. The bladder inflates and deflates as you breath which means that the air from the pump simply reinflates the bladder. The float also holds a rechargeable 12V gel battery (runs for about 45 mins - depending on depth) and so the system is self contained and the float can be towed around behind you as you swim. All works well - max depth about 4 metres.
NOTE - any system that connects your lungs directly to the surface will seriously injure or kill you below about 1 meter!! Including the valves in the pump, my system has 3 non-return valves between my lungs and the surface.

I'm guessing you stole this idea from the early 1950's Practical Mechanics magazine except they used a hot water bottle as a bladder!

 

[terallan]

hookah

Hi folks,
I wonder if I could come into this conversation about hookah, with 17 years experience using just exactly what you're discussing. Firstly, I don't want to enter into a debate about SCUBA Vs Hookah, each has it's own place and one is not a substitute for the other.

I will say though, breathing compressed air underwater has it's potential hazards, as does SCUBA. So long as you are aware of the hazards and have sufficient training in such hazards, then you are your own health and safety council. So long as you know the risks, at least you can make an informed decision to go ahead. What I will say is from a lot of reading from divers (as I am) they seem a little uptight on the subject, to the point that it's scuba or no way, there are 'other' ways out there. Hookah has been used safely and extensively in the gold prospecting/dredging world, which is where I started.

I'm in the UK and have been breathing off hookah for 17 years, so I think I can contribute something positive and accurate to the discussion, as opposed to perhaps speculative input from anyone who has never used hookah and has really no idea what they are talking about.

Hookah and scuba are two separate animals, hookah you want to be using for shallow work, boats, gold prospecting, marina work.

The basics are: clean air compressor, filters, receiver tank, airline, harness and regulator. You will have bouyancy to deal with if using a drysuit, etc., but I won't go into that as that's a separate issue and covered in scuba training.

In a nutshell, you can use hookah down to 9m just about all day without any issues with getting bent, at shallow depths, 1, 2, 3 m, there is not enough nitrogen disolving into the blood to cause any issue. On a lot of diving tables, you will find the dive time 'unlimited' at the these depths, but we'll drill it down to a couple of hours, without any problems for safety sake.

You can drown, that goes without saying, you will need to understand the importance of equalising and not holding a lung with compressed air and surfacing. These issues are covered in SCUBA training and you shoud consider training for this.

Hookah is low pressure and you will find that most systems will be good for a few bars, more than enough for shallow boat work, hull cleaning, anodes and the likes. My own system has two seriously big filters, granular activated carbon and 1 micron particulate filter. This is my personal choice, but most diaphram clean air compressors are OK to supply air direct. I've seen some 5 micron filters about, but I prefer 1 micron.

That's about it, you divers out there, don't get too hung up on not using hookah. There is some reliable kit out there, which I have had for a hell of a long time. The safety I agree 110% with and anyone breathing underwater sould have sufficient training and know the risks, we're all with you on that, so that goes without saying.

Ok, I'll buzz off now, feel free to ask me any questions on my kit and I'll help you with as much accurate info on using hookah as I can.

My kit is Honda diaphram compressor, receiver tank, filters and multiple lengths of line. All worked faultlessly for 17 years (two compressors mind you).