Diving

mattnj said:
errr....already established the breathe out part....
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maybe its established for you as a fairly experienced open water diver, but not for the person who jumps in with no idea what they are doing, gets spooked by something and bolts for the surface....
Can you just be patient and wait for my PM later in the week and perhaps then you'll understand why I get so worked up about this subject.:mad:

Thanks and regards,
 
The question, in my opinion, is whether 'Just breathe out' is sufficient. Even at 1m, holding your breath and surfacing will cause a 10% expansion in the air in your lungs. Since your lungs do not feel pain, you would not realise that they were being stretched, with potentially lethal repercussions, almost immediately.

In may experience, with 20 years as an instructor, people do forget to breathe out. It happens all the time with trainees. The natural thing to do when underwater for the inexperienced is to hold your breath. More so if you are nervous, or scared.

There are loads of potential dangers with diving. As you rightly say, the vast majority of them probably don't apply when diving under your boat. Unfortunately, for the uninitiated, burst lung is a very real possibility.
 
mattnj said:
this could go on forever....what are the potential problems in boats draft depth please, i said right at the beginning that i am happy to be corrected, but what do i actually need to know at shallow/pool depth other than the breath out we have already said.....happy to agree it is dangerous for safety's sake and agree not to take the risk, and have clearly said it is VERY dangerous at any depth over a couple of meters, but you are not actually saying what is dangerous or the potential problems are, you seem to just say it is dangerous for the sake of it, without explaining why and what can happen.....

800 ish people injured on the roads every day in the UK....all things in perpective...probably statistically safer as a beginner diver cleaning your boat that driving on an A road at night... :-)


anyway, enough said, get some training :-)
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There are a whole raft of potential problems that seem trivial, but if you don't have some basic training you could get yourself into a pickle. Here are a few for starters:

1. Your mask leaks. Not a lot, but an irritating trickle that affects your visibility. How do you clear it?
2. You are scrubbing away and you knock your mask off. Can you breathe underwater without a mask covering your nose? Can you replace the mask and clear it and still get the job done?
3. You jam a strap on something (prop, anode, whatever). Are you sure you would have the presence of mind to sort the problem (remove fin/remove pack/whatever) without panicking?
5. Pick any of the above, factor in the poor visibilty from the crud you're scraping off, maybe even some current or a jellyfish sting, and add a measure of equipment failure (your weight belt slips, sticky demand valve, whatever).

The bottom line is that you have to be familiar with your equipment, and be comfortable sorting problems out.

Does that help?


Alisdair
 
agurney said:
There are a whole raft of potential problems that seem trivial, but if you don't have some basic training you could get yourself into a pickle. Here are a few for starters:

1. Your mask leaks. Not a lot, but an irritating trickle that affects your visibility. How do you clear it?
2. You are scrubbing away and you knock your mask off. Can you breathe underwater without a mask covering your nose? Can you replace the mask and clear it and still get the job done?
3. You jam a strap on something (prop, anode, whatever). Are you sure you would have the presence of mind to sort the problem (remove fin/remove pack/whatever) without panicking?
5. Pick any of the above, factor in the poor visibilty from the crud you're scraping off, maybe even some current or a jellyfish sting, and add a measure of equipment failure (your weight belt slips, sticky demand valve, whatever).

The bottom line is that you have to be familiar with your equipment, and be comfortable sorting problems out.

Does that help?


Alisdair
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You missed one.

4. Being unable to count due to nitrogen narcosis.



Sorry. :D
 
dive training, hum

Every time the notion of diving under the boat comes up, some diver instructor rips in with the death threats. Without training (that they sell) you probably risk a horrible DEATH!! Yeah yeah. Then they come out with baloney physics about (this time) fishtanks on your chest - unaware of the fact that your chest is withstanding about 10metres water of absolute air pressure whilst you are ashore. So 2metres is a bit more, not near-death, not anything like it. It's not any multiple of 1metre deep fish tanks sitting on your chest, jeez. Even quite a small fishtank on your chest would crush you, and diving doesn't reliably do this.

Yeah, there are lots of numpties, but lets just pretend that someone who can sail and considering diving under the boat is wel-above averagely practical, and possibly a lot more practical and aware of safety issues too.

Even beginner dive training includes zipping down to 5+ metres on the first day, so it ain't that argh dangerous is it? No. We're talking about going less than two metres down, plenty of time to unclip if you get jammed (unlikely but just about possible i spose) and lots more.

Oh and whilst we're about it - diving under your boat is likely MUCH more safe than going on some dive trip and courses - usually on a flimsy RIB in the UK and almost invariably with an illegally-small alpha flag that risks other boats thinking they've found a free rib and approach the boat with divers down - cos the flag isn't the regulation 1 metre high and visible from all angle (ie a proper rigidly-constructed flag).

/rant
 
I've been a PADI diver for over 25 years and have dived in the North Sea and several West coast lochs, plus Loch Lomand. I also dive in the Caribbean. I don't dive that often now but regularly dive to 20'0" - to check on my anchor.:)

I unreservedly recommend that you do not attempt any SCUBA gear or other so called safe compressed air diving equipment without proper training.

It is OK to hang off the side or float alongside with a wet suit, a 'good' mask and snorkel and scrub as far as you can reach.
IF you are a competent snorkler then you could do a bit more, but please bear in mind 'shallow water black out'.
Make sure that you have somebody as a 'buddy' on the boat or in the water with you to assist in the event you get into difficulties.

Also as an aside, remember you cannot breathe using a 4'0" long snorkel.

When you scrub the bottom you will release clouds of nematocysts (stinging cells) and some of your antifouling. This is not good or recommended for your skin.

I strongly suggest that you employ a qualified diver to do the underwater work.

The risks of diving injuries are high and extensive.

You have already said that you are not a great swimmer.

Your life is not worth it, just to save a few pounds.

Do you wish your family to erect a tombstone - "He died trying to save a few quid" ?
 
Oh lord, every time diving's mentioned the same thing happens...

I would just add that if you do pay a diver to clean the bottom remember it's not a very pleasant job, he's got to get his tank filled, get his gear ready and on, clean it all and himself afterwards, etc. so it's not just the time he spends under the water...

Enjoy your diving all, get some basic training & there's a lot of enjoyment to be had...:D
 
blimey

what have I unleashed?

er ok, i promise to get some training if I dive using scuba gear (which I aint got, and wasn't really in the plan, but hey, think big)

In the meantime, please tell me what's wrong with me plan (buy mask, rent weights and "fins"), and give me some helpful tips. Weather's nice 'n' warm, why shouldn't I want to swim under me boat?

I did read a few diving threads before I posted this, but the way I phrased it I wasn't kinda expecting all this hellfire and brimstone. Maybe I should have known....

I'll let you know how I get on, maybe even start a new thread. :)

In the meantime, please carry on....
 
Normally I would say go for it, and forget all the rubbish. Just use common sense.

However, over the last year I have completed my Advanced Open Water PADI course and I really agree with the poster who listed a handful of the many problems you might experience, even at a few metres underwater.

Diving training is really cheap compared to boating.
For hundreds, as opposed to thousands of pounds you can get some training, and be prepared to do the job properly. Besides all that, the diving itself is great fun and is worth doing anyway.

If you are prepared to risk your own safety to save that amount of money, then I would not criticize. It is your life, and your call. Personally I would rather have the fun of the training and the knowledge that if it all " shurns to tit" I had some training experiences to refer to to get myself out the problem.
 
ytd said:
fisherman2 I would be interested in knowing how how you put together a hookah unit for $150. I've been contemplating the ones at the Sydney boat show but it's hard to justify their $1200 price.
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Several of my friends have these systems you mention. Mine consists of a hookah regulator, $42 off eBay, new from a Melbourne dive shop and exactly the same as the units you mention at the boat show. They normally sell for about $90 to $105 or so. 50 foot of hookah hose off eBay $49. The hose is critical and has to suitable for breathing air so just buy the real stuff new and don't use less than 50 feet. Compressor is a SIP oil less compressor, 240v unit that pumps about 6 cubic feet a minute, only need 2 but with 240v units they tend to be bigger. Mine was off eBay, almost brand new for $40 plus $20 postage. I still need a filter for 5 microns on the output side, they are about $20. The bought units don't have them but its worth the trouble.
If you are after a 12v unit then buy one of the oil less compressors. You need 2 cubic foot of air and a unit that can pump 100psi. 100% cycle rate would be nice too. Check out your mates units and just buy the same compressor, remember these "manufacturers" of these dive systems just buy off the shelf like everyone else.
Check out seabreeze.com.au forums under sailing for further discussion. Plenty of Utube stuff on hookahs. Breath normally at all times.
 
deeb said:
what have I unleashed?

er ok, i promise to get some training if I dive using scuba gear (which I aint got, and wasn't really in the plan, but hey, think big)

In the meantime, please tell me what's wrong with me plan (buy mask, rent weights and "fins"), and give me some helpful tips. Weather's nice 'n' warm, why shouldn't I want to swim under me boat?

I did read a few diving threads before I posted this, but the way I phrased it I wasn't kinda expecting all this hellfire and brimstone. Maybe I should have known....

I'll let you know how I get on, maybe even start a new thread. :)

In the meantime, please carry on....
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No problem with that plan. Weather may be warm, but have a flask of soup prepared for afterwards - unless you are using a decent wet/dry suit you'll end up chilly.
If you are on your own, ensure you have a plan for getting back on board when you are exhausted (i.e. don't just jump overboard then remember the dinghy's still in a locker!).

Alisdair
 
deeb said:
what have I unleashed?

er ok, i promise to get some training if I dive using scuba gear (which I aint got, and wasn't really in the plan, but hey, think big)

In the meantime, please tell me what's wrong with me plan (buy mask, rent weights and "fins"), and give me some helpful tips. Weather's nice 'n' warm, why shouldn't I want to swim under me boat?

I did read a few diving threads before I posted this, but the way I phrased it I wasn't kinda expecting all this hellfire and brimstone. Maybe I should have known....

I'll let you know how I get on, maybe even start a new thread. :)

In the meantime, please carry on....
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Don't worry, if you just add a few things such as which anchor you use, and the colregs for diver down when scrubbing a hull, people will calm down a lot, and the thread will draw to a conclusion very shortly :)
 
Nah.
It's another of those "I am an insructor and there is only my way of doing things" threads.
HSE and AALA are the bane of right-thinking people's lives.

Some git will come now along and use my use of the word "lives" to insinuate that lives are at risk because all untrained people are suicides waiting to happen
 
rogerstown said:
Seems to be lots of good safety advice here. I am considering getting the correct equipment and diving to check my moorings. Is there anybody with advice on training for the over 60s ?
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There's a few things in the PADI Open Water course that you need a certain level of fitness to do, particularly 10 minute tread water and 200m swim (not timed). Being grossly overweight, having a heart condition or asthma might mean it's inadvisable but otherwise go for it! You might choose one to one instruction or at least a small group (no more tha 4 students to 1 instructor, say).

Most diving is (and should be) fairly relaxed and relaxing, not some kind of macho action man activity. Enjoy...:)
 
Lakesailor said:
Nah.
It's another of those "I am an insructor and there is only my way of doing things" threads.
HSE and AALA are the bane of right-thinking people's lives.

Some git will come now along and use my use of the word "lives" to insinuate that lives are at risk because all untrained people are suicides waiting to happen
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Well I'm one (an instructor not a git) and I wouldn't recommend throwing on some gear and going diving without a clue what you're getting into. I wouldn't have before I started. However it's not rocket science, a basic course is all anyone needs to get started. As I said much earlier in the thread, dive shops should check you have a cert before they fill your tank...
 
I also did SCUBA PADI training many years ago. I was struck by the fact that to actually go down and breath is really easy. Easier than snorkelling. However we had many days of training all experience. Some of the exercises done was removing mask and refitting clearing. Removing weight belt and refitting. Removing tank and refitting. All of these exercises are never or seldom actually needed. What they do though is get you more imune to panic.
A person with 18kgs of tank on his back 12kgs of lead belt and another 12 or more kgs of wet wet suit feels very arkward on climbing out of the water or getting in. This can translate to a feeling of vulnerability and tendency to panic. Any panic has a tendency to make a person hold their breath and go fast for the surface. Hence concern about air in lungs expansion. It doesn't of course burst the lungs but rather forces air bubles into the blo0od which can be disastrous. Obviously 2 metre deptyh from under a keel is not so dangerous but still not good. So yes training is well worthwhile doing. I confess however that my first diving experiences on SCUBA were before training.
To the original poster don't rent mask snorkel and fins or even wet suit. Buy them and keep them on the boat. You never know when you will need them. While a wet suit is expensive the rest of the gear is cheap. The trick is to do bits often so toal effort is not to much just enough to be fun. olewill
 
tcm said:
Every time the notion of diving under the boat comes up, some diver instructor rips in with the death threats. Without training (that they sell) you probably risk a horrible DEATH!! Yeah yeah. Then they come out with baloney physics about (this time) fishtanks on your chest - unaware of the fact that your chest is withstanding about 10metres water of absolute air pressure whilst you are ashore. So 2metres is a bit more, not near-death, not anything like it. It's not any multiple of 1metre deep fish tanks sitting on your chest, jeez. Even quite a small fishtank on your chest would crush you, and diving doesn't reliably do this.
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1. I don't sell training, and neither do the majority of BSAC clubs, one of which, I am a member.

2. The physics is not baloney, you clearly just don't understand it.

3. The fish tank analogy is correct. If you don't believe it, make yourself a 3ft snorkel and try and breath through it.

4. Do you actually have any concept of quite why it is that your lungs are not compressed by the weight of water? Do you know how a demend valve works? Does the concept of breathing compressed air actually register with you?

5. It's not really 'some dive instructor' now, is it. at a rough guess it seems to be around four experienced divers here saying the sme thing. That's all of us. All of us with baloney physics trying to sell you something?

Lots of people read these fora. Of course there are numpties who know better when something is being explained to them, but the majority will have a read and have a think, not shoot their mouth off about something they do not understand.

I'm happy to debate the physics with you, and provide references if you feel you do understand and would wish to.

Cheers.
 
Lakesailor said:
Nah.
It's another of those "I am an insructor and there is only my way of doing things" threads.
HSE and AALA are the bane of right-thinking people's lives.

Some git will come now along and use my use of the word "lives" to insinuate that lives are at risk because all untrained people are suicides waiting to happen
Click to expand...

No, I'd say it was one of those 'There are hidden dangers, find out a bit about it before doing' it threads.

There are a few gits about twisting words, mind..........
 
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