Hookah snorkeling / diving

[srm]

I scrubbed off a boat underwater using SCUBA gear. Anchored in a depth with the keel almost on the bottom. Wore slightly more weight than usual for diving and stood on the bottom while working. Other times I hung a weighted line under the keel to give a hand hold.
Much easier in the marina berth was using a pressure washer rather than hand scrubbing. Yes they do work underwater with the nozzle very close to the hull, all be it more slowly than in air, but that was with Coppercoat, it blasted small barnacles off the prop and anode but big old ones needed a scraper. The length of the lance allowed me to clean most of the boat while floating on the surface with a normal snorkel.

 

[RogerJolly]

Is it not painful for your lungs to be pressurised to damaging levels (guess we're talking relative pressure here). Would have thought you'd exhale instinctively.

Or maybe over an evolutionary timespan we've never been subject to artificially pumped up lungs, so we've never needed our nervous systems to be able to deal with it.

 

[lustyd]

You do notice it, but it could be too late if you come up quickly hence the advice

 

[DinghyMan]

Is it not painful for your lungs to be pressurised to damaging levels (guess we're talking relative pressure here). Would have thought you'd exhale instinctively.

Or maybe over an evolutionary timespan we've never been subject to artificially pumped up lungs, so we've never needed our nervous systems to be able to deal with it.

You will find that lung expansion injuries, pulmonary barotrauma, are painful and can be fatal

They are also a cause of arterial gas embolisms, which again can range from mild pain to fatal

Neither are a good idea

Gas management and planning should mean CESA is never needed but they dont seem to be taught as much as they should

 

[srm]

Is it not painful for your lungs to be pressurised to damaging levels (guess we're talking relative pressure here). Would have thought you'd exhale instinctively.

Probably not until you do serious damage.
Last year I had a medical probe stuck up my nose and down into my lungs. Very painful as it was passed through the nose and throat but blissfully unaware of what they were doing inside my lungs. Likewise lots of people happily inhale various gases and toxins at fairly high temperatures so obviously the interior of the lungs are not very sensitive to pain.

 

[Graham_Wright]

Sounds like you're so panicky your rapid breathing will sort out your ascent problems!
But, seriously, avoid bad air intake into the compressor. It can be a killer.

 

[William_H]

Tee-shirt to protect your back from sun burn

Yes I wear a hat also. Tricky when diving but stays on. I forgot to mention for larger boats a rope from bow to stern just touching the water gives you something to rest and hang on to. ol'will

 

[RogerJolly]

What do we think of those hand-pumped mini-cylinders?

Dire warnings here, but maybe they would say that to stop people cheaping out and reducing their revenue selling expensive kit (not incompatible with being true I guess).

Pumping definitely looks to be hard work, but maybe not a problem for only brief and occasional use. Could maybe do a few pumps a day for a week prior to use. Wonder how long they hold a charge.

 

[lustyd]

Was looking at a 2L cylinder yesterday, very tempted but the one with the 12V compressor is quite pricey and a hand pump won't get you very far.

 

[Skylark]

What do we think of those hand-pumped mini-cylinders?

Dire warnings here, but maybe they would say that to stop people cheaping out and reducing their revenue selling expensive kit (not incompatible with being true I guess).

Pumping definitely looks to be hard work, but maybe not a problem for only brief and occasional use. Could maybe do a few pumps a day for a week prior to use. Wonder how long they hold a charge.

I’ve never seen a 200 bar hand pump so can’t comment. It takes a lot of effort to put 2 bar into my car tyres.

A normal diver breathing rate at the surface, typically used for dive planning, is 25 l/min.

The device in question has a 0.5l cylinder and can be hand pumped to 200 bar. That equates to 100 litres of air at surface, ambient pressure.

Say, dive depth is 5m, equivalent to 1.5 bar absolute pressure. Air consumption at this depth is then 1.5 x 25 = 37.5 l/m.

Hence cylinder would last 100/37.5 = 2 mins 40 seconds.

All of the “dire warnings” on the linked website seem valid. Run away.

 

[Beneteau381]

I’ve never seen a 200 bar hand pump so can’t comment. It takes a lot of effort to put 2 bar into my car tyres.

A normal diver breathing rate at the surface, typically used for dive planning, is 25 l/min.

The device in question has a 0.5l cylinder and can be hand pumped to 200 bar. That equates to 100 litres of air at surface, ambient pressure.

Say, dive depth is 5m, equivalent to 1.5 bar absolute pressure. Air consumption at this depth is then 1.5 x 25 = 37.5 l/m.

Hence cylinder would last 100/37.5 = 2 mins 40 seconds.

All of the “dire warnings” on the linked website seem valid. Run away.

My air gun pump does that pressure but not a lot of volume

 

[RogerJolly]

What about using a Rule high speed dinghy inflator as a hookah pump? Just for diving no more than 1m.

Would it work, according to list below, or is list wrong somewhere and/or there’s some other factor that makes it dangerous? (Have NO experience of diving, apart from 10 mins tourist dive in Egypt.)

• Breathing at depth only needs air to be at supplied at the surrounding water pressure for it not to be a struggle to breathe at that depth.
• A second stage diving regulator supplies air on demand at the surrounding water pressure, whatever the pressure it is being supplied with.
• At 1 m depth the pressure is about 1.5 psi.
• Would be breathing around 25 litres/min of air.
• A Rule high speed inflator, according to specs, can supply 55 litres/min at 2.6 PSI.
• All would be fine with Rule inflator supplying air to a typical second stage regulator.

 

[srm]

It may well work. Some time back there was a thread on DIY surface supply diving gear. I think they were using a pool aeration pump. I have used a vacuum cleaner motor and fan to supply a full face mask at positive pressure when spraying two part insulation foam (but not underwater).
I would suggest some diving training before experimenting with DIY gear, to get confident under water so that knocking your face mask off or suchlike will not cause momentary panic.
How long will the inflator motor run before overheating or cutting out as normal use is probably for 5 to 10 minutes?

 

[RogerJolly]

It may well work. Some time back there was a thread on DIY surface supply diving gear. I think they were using a pool aeration pump. I have used a vacuum cleaner motor and fan to supply a full face mask at positive pressure when spraying two part insulation foam (but not underwater).
I would suggest some diving training before experimenting with DIY gear, to get confident under water so that knocking your face mask off or suchlike will not cause momentary panic.
How long will the inflator motor run before overheating or cutting out as normal use is probably for 5 to 10 minutes?

Good points thanks. Thinking only a couple of minutes running would be fine. Dove down to scrub prop the other day, stressful having to come up for air every 15 secs or so, but total only 5 or 6 dips.

 

[rogerthebodger]

I have done both SCUBA and HOOKAH diving and infect made a HOOKAH dive compressor from a oilless spray compressed I had in my garage.

IF I dive just to give my boat a clean, I sometimes just place my tank on deck with a long hose to my stage 2 regulator and work from there.

Getting your buoyancy correct is the major issue and I would recommend getting a hard hat and cutting holes in it to protect you head when buoyancy is not correct, and you bash you head on the underside of the hull

I also have a floating hookah set battery driven but never used it in anger

 

[srm]

Dove down to scrub prop the other day, stressful having to come up for air every 15 secs or so, but total only 5 or 6 dips.

Yes, I used to do that but then found an easier solution. If you are in a berth with mains power and water tap use a pressure washer. I used to clean my prop and anodes with a pressure washer. Just floated on the surface with a snorkel and the lance reached the prop etc. Quite satisfying seeing it blast clumps of barnacles off, but better not to let them grow too big as they then need scraping off.

 

[Skylark]

We all are entitled to an opinion and should respect the views of others but for me, as a recreational diving instructor of more than 30 years standing, I’d say @roger Jolly that it’s a crazy idea and emplore you not to do it. I’m far too risk averse to even think about, especially when kit and training is so accessable.

 

[srm]

We all are entitled to an opinion and should respect the views of others but for me, as a recreational diving instructor of more than 30 years standing, I’d say @roger Jolly that it’s a crazy idea and emplore you not to do it. I’m far too risk averse to even think about, especially when kit and training is so accessable.

As an ex-club diver who also dived on a part time commercial basis I understand where you are coming from, and agree that for anyone wanting to dive recreationally training is the only safe way to go. Also, anyone wanting to use a shallow water surface demand, commercial or DIY, needs to be confident and competent underwater which requires training.

From time to time I have looked at commercially produced surface demand kits just for cleaning and checking my boat's hull, but the price did not justify the two or three hours a year use they would get. SCUBA gear with cylinders to fill and service would have been heavy overkill. I suspect that is where the interest in DIY aids for reaching one to two metres below the surface comes from.

 

[RogerJolly]

Taking all on board...

SRM has it – hate the idea of kit lying around hardly ever used (speaking as a tight Yorkshireman). Can’t be green either.

Liking the pressure washer idea. Have heard of dangers of electric shock though from stray currents swimming in marinas (ESD), so might try reaching under from pontoon or dinghy. (Now I’ve flipped to being the cautious one.)

 

[srm]

Liking the pressure washer idea. Have heard of dangers of electric shock though from stray currents swimming in marinas (ESD), so might try reaching under from pontoon or dinghy.

You will need to see exactly where you are pointing the lance as it needs to be very close to be effective. I have used it to poke barnacles off. An old fashioned water glass, a sort of long glass bottomed bucket, may help but you need to reach under the hull.