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... If you pre-arranged with your buddy that if you get separated that you would continue on as solo divers that’s great. Most arguments I have seen at dive sites are between buddies when their expectations are not one in the same. Nothing worse than losing a buddy, looking for the suggest period (based on your training agency), aborting the dive and surfacing to find them no where in sight. Even when everyone makes it back no problem this situation always seems to end in a heated exchange.

At least NWDiver isn't saying that after the separated divers relocate each other at the surface (assuming they actually do) that they should subsequently re-descend and resume the dive, a procedure still taught by some training agencies - including, if I'm not mistaken, McPADI ("Over Five Million Sold)". Bob Halstead is just one of the knowledgeable, experienced divers who has condemned this practice as unsafe (in an Undercurrents article some years ago). Except in situations where the depths involved are trivial, I find it hard to believe that anyone here would adhere to the practice of surfacing to relocate a lost buddy and then re-descending. Not a good idea.

 

Halstead may also be the foremost exponent of the argument that diving with a buddy actually increases the potential risks of diving. His diatribe (in a now famous "Aquacorps" article) "On your own: the buddy system refuted" is well worth reading, and has been extensively discussed on other online and other forums over the years.

 

I think Halstead makes the case against the buddy system - or at least the simplistic buddy diving practices taught by some training agencies - far better than I ever could. For what it's worth, if I'm diving with a beginner or inexperienced diver who requires constant monitoring, then I simply don't bring my camera with me. In that situation, we're not diving as buddies - I'm diving in the capacity of an (unpaid) instructor or dive guide. If I run into a problem on the dive myself, I know I will have to deal with the problem on my own while remaining responsible for the safety of the diver I'm accompanying. And I certainly won't be expecting help from the person I'm with.

 

If you are a "dependent" diver (McPADI's other motto: "Are you co-dependant? We will certify you!") and you don't have a friend willing to take care of you underwater for free (thus ensuring that service you receive will be worth at least what you are paying for it), then you should bite the bullet and hire a real, qualified instructor. No shame in that - I will always hire an instructor (or rely on a much more experienced colleague/friend) to help me on any dive that I have reason to believe may be beyond my experience or capability.

 

What's really insane - and may be the McPADI's ("The way the world learns to dive") most important contribution to unnecessary and avoidable dive fatalities - is the practice of pairing off divers according to experience and skills and forcing them to dive together as buddies, thus ensuring that the two least experienced divers in the water - the two persons who are simultaneously the most likely to require assistance during the dive and also the two who are least qualified to give it, will dive together. Great system.

 

Frogfish (Our buddy motto: "Same ocean, same day")

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At least NWDiver isn't saying that after the separated divers relocate each other at the surface (assuming they actually do) that they should subsequently re-descend and resume the dive, a procedure still taught by some training agencies - including, if I'm not mistaken, McPADI ("Over Five Million Sold)". Bob Halstead is just one of the knowledgeable, experienced divers who has condemned this practice as unsafe (in an Undercurrents article some years ago). Except in situations where the depths involved are trivial, I find it hard to believe that anyone here would adhere to the practice of surfacing to relocate a lost buddy and then re-descending. Not a good idea.

Can you please explain the problem with re-descending? I read the Halstead article and it seems to be more directed against the surface relocation that the re-descending, and doesn't actually say what the problem with descending again actually is.

 

On a number of sites I dive, I have used the surface relocation and re-descening on a number of occasions without any issues at all - and only a slight inconvenience. These were shore dives in water less than 10 metres and returning to the entry point to meet up with the buddy would have been a significant inconvenience. Additionally, had something bad happened to my buddy, I would have essentially been leaving him for dead - especially if he had surfaced with a major problem.

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At least NWDiver isn't saying that after the separated divers relocate each other at the surface (assuming they actually do) that they should subsequently re-descend and resume the dive, a procedure still taught by some training agencies - including, if I'm not mistaken, McPADI ("Over Five Million Sold)". Bob Halstead is just one of the knowledgeable, experienced divers who has condemned this practice as unsafe (in an Undercurrents article some years ago). Except in situations wherethe depths involved are trivial, I find it hard to believe that anyone here would adhere to the practice of surfacing to relocate a lost buddy and then re-descending. Not a good idea.

 

Halstead may also be the foremost exponent of the argument that diving with a buddy actually increases the potential risks of diving. His diatribe (in a now famous "Aquacorps" article) "On your own: the buddy system refuted" is well worth reading, and has been extensively discussed on other online and other forums over the years.

Thank you for that, I've been searching for years for that article which made me think about this subject a lot more, resulting in my own article on the subject. I should have realised it was likely to be on Jim "Cobber" Cobb's Trimix page, mine is as well.

 

It's interesting that it's not on Bob's website. But then, he's a McPADI Instructor nowadays. :P

 

If you are a "dependent" diver (McPADI's other motto: "Are you co-dependant? We will certify you!") and you don't have a friend willing to take care of you underwater for free (thus ensuring that service you receive will be worth at least what you are paying for it), then you should bite the bullet and hire a real, qualified instructor. No shame in that - I will always hire an instructor (or rely on a much more experienced colleague/friend) to help me on any dive that I have reason to believe may be beyond my experience or capability.

To be quite fair to the McPADIs of this world the search, surface, relocate and then redescend now has a caveat.

 

What's really insane - and may be the McPADI's ("The way the world learns to dive") most important contribution to unnecessary and avoidable dive fatalities - is the practice of pairing off divers according to experience and skills and forcing them to dive together as buddies, thus ensuring that the two least experienced divers in the water - the two persons who are simultaneously the most likely to require assistance during the dive and also the two who are least qualified to give it, will dive together. Great system.

This is still something that makes me positively spit whenever I see it. No way should, as an example, novice divers be buddied with each other. That is just ludicrous, absurd. If I saw that happen (and there was no other course of action) I would volunteer to dive with them and forego the camera (as would you, I'm sure).

 

Robert, nice to see that Bali is alive and well, hope that hound of yours is also still happily romping around. :wacko:

 

Allow me to make a couple of general observations not at all related to your post:

 

* The Spare Air (sometimes, commonly?, called the Spare Death in certain circles) does not a self sufficient diver make - even a "solo" diver make. What's more, I don't even care if you restrict yourself, severely, to 10 metres or less.

 

* Depth has nothing to do with self sufficiency. You can get into the deepest of sh!t at any depth. Think barotrauma as just one example. Task loadings when it hits the fan make people do very stupid things, the common one of which in our situation is the holding of one's breath. Not at all good idea at 10 metres.

 

* CESAs, as the McPADIs put it, are all well and good. Guess what? The real situation will always be different. I defy most divers to do a proper CESA when it actually counts.

 

* Someone asked why ascending and then redescending was not a good idea. I suggest that they carefully read their decompression procedures/dive tables. Oops, forgot about that one - the McPADIs don't do decompression - silly me. :ninja:

 

Cheers,

 

Christian

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On a number of sites I dive, I have used the surface relocation and re-descening on a number of occasions without any issues at all - and only a slight inconvenience. These were shore dives in water less than 10 metres and returning to the entry point to meet up with the buddy would have been a significant inconvenience. Additionally, had something bad happened to my buddy, I would have essentially been leaving him for dead - especially if he had surfaced with a major problem.

I know I shouldn't do this, I really shouldn't. It's late, I'm tired, but I'm also stewing about it.

 

There are a number of issues here:

 

1) Your comments would lead many to think that getting separated (and needing to get "reattached") is the norm rather than the exception?

2) "Leaving him for dead?" Excuse me? If you've already lost him you've already done that haven't you?

3) If, as it appears, that you regularly dive with this buddy, do you (a general "you") perhaps have a problem with your procedures? Should you really get separated as often as it seems that you do?

 

I'm sorry, this is singularly rude of me, but diving doesn't really take any prisoners, you survive, or you're dead. Mostly anyway.

 

Cheers,

 

Christian

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As I've already said, the topic of Solo Diving always stirs up a lot of opinions. However....

 

Just to add my own caveat to the discussion: discussing solo diving is a perfectly reasonable thing to do and with 'experienced', 'competent' divers it is a very valid topic indeed which has been discussed many times by eloquent advocates with views both for and against, BUT (there is always a but).....

 

Advocating a procedure such as solo diving, which carries a potentially higher risk for those who are NOT sufficiently 'experienced' or 'competent', should always be done with caution. I have seen many divers accept solo diving as a perfectly reasonable practice and whilst most also take on board the need for greater gear redundancy, better knowledge of emergency bail-out procedures, etc, there are some who don't - usually because they believe that their experience level is higher than it actually is.

 

Unfortunately, one of the aspects of diving which I personally think is lacking in ALL dive training I've come across is experience underwater (logged hours basically) which is a great pity because in my experience, there is nothing to beat experience (I would like to see a minimum number of logged dive/hours logged between qualification 'steps' personally). Badges, tickets, courses are all very well but too often lack built in experience. I would suggest to anyone seriously considering solo diving to really look objectively at their diving experience, equipment suitability and service history (could I tell you some horror stories on this topic or what?), and mental attitude (someone mentioned the 'just another few meters down, few minutes more' attitude) before actually soloing. Dive within our own capabilities (especially when task loaded with a camera) and the undersea is a relatively safe place, outside them it can and sometimes is, lethal.

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"* The Spare Air (sometimes, commonly?, called the Spare Death in certain circles) does not a self sufficient diver make - even a "solo" diver make. What's more, I don't even care if you restrict yourself, severely, to 10 metres or less."

 

Since I just purchased one of these, your comments make me want to ask why. It seems to be a decent product for recreational depths.

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I know I shouldn't do this, I really shouldn't. It's late, I'm tired, but I'm also stewing about it.

You are correct. You should not have done it.

 

There are a number of issues here:

And the biggest issue is making an poor assumption and then making conclusions based on that (wrong) assumption.

 

1) Your comments would lead many to think that getting separated (and needing to get "reattached") is the norm rather than the exception?

Are you serious? How could you possibly come to that conclusion based on what I have said? Saying "a number of occasions" implies more than once. Nothing more, nothing less. So not only do you jump to a conclusion about me, you are also assuming that others are going to make the same mistake you have. Sigh.

 

2) "Leaving him for dead?" Excuse me? If you've already lost him you've already done that haven't you?

Again, are you serious? Becoming separated from a buddy does not mean he is dead.

 

3) If, as it appears, that you regularly dive with this buddy, do you (a general "you") perhaps have a problem with your procedures? Should you really get separated as often as it seems that you do?

The only thing apparent here is you have made a completely unsubstantiated conclusion about something and someone you know nothing about.

 

I'm sorry, this is singularly rude of me, but diving doesn't really take any prisoners, you survive, or you're dead. Mostly anyway.

It was exceedingly rude and ignorant of you.

 

Cheers,

Whatever.

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Most of my photo dives are solo. I prefer to take photo's in reasonably shallow water (less than 15m) and feel quite comfortable being able to deal with any emergency at that depth. I have worked as a guide, instructor and photographer underwater for many years and have dived solo throughout that time where the situation allowed. After all, any one teaching a group or guiding is practically solo anyway.

It is quite aparent that many of the people that make such a fuss over solo diving wouldn't bat an eyelid over their guide solo diving to tie the boat onto the dive site that they wanted to visit. People who work in the diving game solo dive every day, it is part of their job. The secret is to dive within your limitations and comfort level. As always!

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I always sign the liability disclaimer and the terms & conditions form (usually advocating a buddy system) offered to me at the start of any dive trip, but after a six hour session in the witness box I always now add the caveat that "I can in no way be held responsible for the well-being of any other person in the water."

 

What does that mean? I dive alone - although there may be other people in the water near me..

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I always sign the liability disclaimer and the terms & conditions form (usually advocating a buddy system) offered to me at the start of any dive trip, but after a six hour session in the witness box I always now add the caveat that "I can in no way be held responsible for the well-being of any other person in the water."

 

What does that mean? I dive alone - although there may be other people in the water near me..

Thank you jb, and you are, I am sure and certain, not alone in those sentiments.

 

Cheers,

 

Christian

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You are correct. You should not have done it.

And the biggest issue is making an poor assumption and then making conclusions based on that (wrong) assumption.

Are you serious? How could you possibly come to that conclusion based on what I have said? Saying "a number of occasions" implies more than once. Nothing more, nothing less. So not only do you jump to a conclusion about me, you are also assuming that others are going to make the same mistake you have. Sigh.

Again, are you serious? Becoming separated from a buddy does not mean he is dead.

The only thing apparent here is you have made a completely unsubstantiated conclusion about something and someone you know nothing about.

It was exceedingly rude and ignorant of you.

Whatever.

Phew!!!!

 

Enough said.

 

Cheers,

 

Christian

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Can you please explain the problem with re-descending? I read the Halstead article and it seems to be more directed against the surface relocation that the re-descending, and doesn't actually say what the problem with descending again actually is. On a number of sites I dive, I have used the surface relocation and re-descending on a number of occasions without any issues at all - and only a slight inconvenience. These were shore dives in water less than 10 metres and returning to the entry point to meet up with the buddy would have been a significant inconvenience. Additionally, had something bad happened to my buddy, I would have essentially been leaving him for dead - especially if he had surfaced with a major problem.

ATJ, I'm happy to do so. Halstead's Undercurrents piece does focus on the problem of people surfacing alone, and not at the place and time that the chase/tender boat driver might expect, which is serious enough. The problem with ascending and redescending is that your nice safe dive profile has just turned into a nasty double spike. Your computer probably won't take that into consideration. Suunto and Mares computers with partial RGBM implementations should try to compensate by cutting your bottom time for the remainder of your dive, at least in theory. The purpose of RGBM, however, is not to make it possible to dive suicidal profiles, and no reduction in bottom time on the second half of the dive could ever make ascending and redescending safe.

 

Let's say you and I did a dive together to 30 meters, then ten minutes after we surfaced, I said, screw the surface interval, let's do another dive to the same depth right now. Would you agree to go with me? If not, then why would you ever consider doing a second dive after a surface interval of only one minute?

 

The problem with a quick re-descent is that it can recompress those zillions of nitrogen bubbles streaming out of your tissues into your bloodstream after your ascent to look for your missing buddy (and you probably didn't do a 3 minute safety stop either, did you?) so that they become small enough to pass through the lung barrier to the arterial side, where they can then re-expand after your second ascent. That can be where a serious problem starts, and that's why cutting bottom time after the re-descent won't protect you. This is why we do surface intervals between dives, and why sawtooth dives (even with only two "teeth") can kill you.

 

There is apparently some new data showing that divers (often a divemaster) are particularly vulnerable to DCS after doing a quick dive or free-dive down to free the anchor following a normal dive, even though this is usually redescending to only 12 meters or so, and only for one or two minutes - hardly any "bottom time" on the "2nd descent" at all, really.

 

I assume that ascending and redescending to and from depths of ten meters or less would be much less likely to cause DCS problems - I think I did qualify the comment in my original post to apply to "non-trivial depths." But I have seen people ascend to look for a missing buddy from depths in the 30 meter range, then re-descend to the same depth ... and not always with their buddy either. (So what was the point of that?).

 

BTW, I think you were a little harsh in your response to ChristianG. Is somebody up past their normal bedtime?

 

Frogfish (Robert Delfs)

Edited by frogfish

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Being someone who has only been diving for 3.5 years I view all diving as solo! You are not sharing anything unless you are tech diving and carrying a 1/3 gas for your buddy? Please correct me? I have always found the concept of a buddy being problematic. Mainly because you cannot talk underwater. When I was learning the hand signals for low and OOA I always thought in this situations would I really be able to signal? I (we) am a solo divers in that my wife and I both dive but dive alone and not with a commerical company. I have found that the commerical dive companies that we have used put you at risk. -no comment-

 

The greatest flaw in diving in my small world, PADI, is that it doesn't require re-certification. Can anyone quote stats for problems, incidents and deaths related to time from initial certification and/or their last dive? I am sure its related (in rec diving). I feel PADI should require re-certification, if you can't pass, you take course over. At least driving makes you take the written and driving test over occasionally and diving has a perceived higher risk. Are there any diving certification organizations that require re-certification? I may get certified by them.

 

My wife is moderately tolerant of my UW photography, I have looked up and have found and underwater hand on the hip... :ninja: Especially, since I get the same thing on land! :P

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ATJ, I'm happy to do so.

Thanks, Robert My responses are in bold.

 

Halstead's Undercurrents piece does focus on the problem of people surfacing alone, and not at the place and time that the chase/tender boat driver might expect, which is serious enough.

 

I fully understand those comments and agree that in some and even many situations, surfacing alone is a dangerous thing for the reasons he outlined.

 

Not every dive is a boat dive or relies on a tender boat. The vast majority (if not all) of my regular dives are shore dives with no boat. They are also in areas where if surfacing is required, it can be done safely - and if it can't be done safely, it isn't done at all.

 

Even on boat dives it may be possible to surface safely - but that obviously depends on the site and specifically the terrain in that location. For example, a dive on a pinnacle where the amount of horizontal movement is small and you are staying very close to the wall for the whole dive.

 

The problem with ascending and redescending is that your nice safe dive profile has just turned into a nasty double spike. Your computer probably won't take that into consideration. Suunto and Mares computers with partial RGBM implementations should try to compensate by cutting your bottom time for the remainder of your dive, at least in theory. The purpose of RGBM, however, is not to make it possible to dive suicidal profiles, and no reduction in bottom time on the second half of the dive could ever make ascending and redescending safe.

 

Let's say you and I did a dive together to 30 meters, then ten minutes after we surfaced, I said, screw the surface interval, let's do another dive to the same depth right now. Would you agree to go with me? If not, then why would you ever consider doing a second dive after a surface interval of only one minute?

 

I don't think your analogy is valid. If it had been a full dive of 40 minutes plus I would definitely not consider it. But we aren't talking about a full dive here. We are talking about a dive that has been cut short for some reason. Further, when I do a 30 metre dive, I don't stay at 30 metres for the whole dive. I wouldn't stay there for more than 10 minutes and in most cases much less. The rest of the dive would be spend gradually getting shallower.

 

Now, I'm not advocating a surface search for a 30 metre dive, however, for the sake of the discussion I will pretend that I do. Let's assume that my buddy and I got separated and we couldn't find each other on the bottom and decided to surface. It would either be early in the dive which means the residual nitrogen would be lower or it would be later in the dive and a) it is unlikely we ascended from 30 metres and b ) we wouldn't consider going back to 30 metres. In my opinion, it is not even possible to generalise on what the course of action would be at that point because it would be dependent on the dive time and the depth from which the emergency ascent started. We might abort the dive. We might go back to 5 metres. We might go to 10 metres. It all depends.

 

I should add that I would recommend against diving a 30 metre site in poor visibility as the poor visibility greatly increases the chances of becoming separated from your buddy and makes it a lot harder to find them. With good visibility, you should never lose your buddy and so there is no need for the surface search, As a 30 metre dive includes more risk, you should also be far more aware of your buddy and the only reason to surface would be due to gear failure. In that event, you could do an appropriate ascent as buddies (sharing air as required) and the idea of descending again would not be considered. Note also that a gear failure when diving alone may mean a rapid ascent without safety/decompression stops.

 

The problem with a quick re-descent is that it can recompress those zillions of nitrogen bubbles streaming out of your tissues into your bloodstream after your ascent to look for your missing buddy (and you probably didn't do a 3 minute safety stop either, did you?) so that they become small enough to pass through the lung barrier to the arterial side, where they can then re-expand after your second ascent. That can be where a serious problem starts, and that's why cutting bottom time after the re-descent won't protect you. This is why we do surface intervals between dives, and why sawtooth dives (even with only two "teeth") can kill you.

 

Again, this will depend very much on the depth from which you ascended and how long you were there. As I said above, I don't advocate a surface search from such a depth (30 m) and also any ascent would be with appropriate safety stops - again dependent on the depth and duration. These zillions of nitrogen bubbles streaming out of your tissues into your blood stream would be a problem anyway and suggest that you had more of a problem with your ascent than the subsequent descent and also that agreeing with your buddy to surface search before a deep dive was a bad idea.

 

Does this also suggest that recompression is not the right treatment for DCS? It was my understanding that you want to recompress the divers as quickly as possible after a DCS or potential DCS incident.

 

There is apparently some new data showing that divers (often a divemaster) are particularly vulnerable to DCS after doing a quick dive or free-dive down to free the anchor following a normal dive, even though this is usually redescending to only 12 meters or so, and only for one or two minutes - hardly any "bottom time" on the "2nd descent" at all, really.

 

Again, this sounds like we are talking about divers that have completed full dives. They would have been heavily loaded with nitrogen before they did the quick dive and that quick dive is only going to add to the residual nitrogen so it seems logical to me that they would be more vulnerable to DCS.

 

I assume that ascending and redescending to and from depths of ten meters or less would be much less likely to cause DCS problems - I think I did qualify the comment in my original post to apply to "non-trivial depths." But I have seen people ascend to look for a missing buddy from depths in the 30 meter range, then re-descend to the same depth ... and not always with their buddy either. (So what was the point of that?).

 

I definitely agree that a surface search on a 30 metre dive is a bad idea. Even 20 metres is pushing it, unless it was very early in the dive and going back to 20 metres would be unwise. I have no problem at all with the procedure for dives to 10 metres or less - unless subsequent dives to deeper than 10 metres are planned for the same day. I even think that dives to 15 metres it is fine, as long as the dive is short and it is the only dive of the day.

 

I don't agree with making the sorts of generalisations that Halstead makes about the procedure. Yes, it can and does have problems in certain situations, but I don't believe you need to throw the "baby out with the bathwater". Driving at 110 km/h in a school zone is plain stupid, but that doesn't mean you shouldn't drive at 110 km/h on a freeway.

 

I agree that there are some situations where a buddy is a disadvantage and possibly even a risk but there are also some situations where diving with a buddy reduces risk. I believe it ensuring people are educated and allow them to make informed decisions about what is or isn't appropriate in a certain situation.

 

BTW, I think you were a little harsh in your response to ChristianG. Is somebody up past their normal bedtime?

 

Perhaps I was a little harsh. Perhaps I was just reacting to the completely baseless accusations about me, my diving and my performance as a buddy. How do you think you would react if out of the blue someone with whom you have never previously spoken, let alone met, started to publicly suggest that you were a poor diver?

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This has got a bit out of hand. As far as I'm concerned, the recent twist in this thread wasn't really about your diving skills, atj, whatever those may be. If you will recall, we were talking about solo diving, which led me to recall and post links to the thoughtful articles which Bob Halstead wrote on the subject of buddy diving and the practice of surfacing to relocate a missing buddy some years back. I thought these articles might be of interest here because so many divers seem to assume that buddy diving is the sine qua non of safe diving and that other practices and procedures learned during their 4-day McPADI course (like ascending to locate a missing buddy, wearing a snorkel on mask) are both safe and universally applicable to almost all dives. Some of us question those assumptions.

 

You asked me if I could explain why ascending and then reascending might be a bad idea, and that's what I tried to to in my last post. I also made it clear that I personally didn't think these considerations were particularly critical on a dive to 10 meters, which is apparently what you were concerned about, and reminded you that the original comments about the practice of ascending and redescending were explicitly in reference to dives to "non-trivial depths".

 

I confess that I can't really follow the distinction you seem to be trying to make between a "full dive" and something less than a full dive. Is a full dive "emptying the tank", finishing off a memory card, or what? In any case, I don't think I've ever seen any reference to a distinction between "full dives" and "half" or "quarter" dives in anything I've ever read in modern dive decompression theory or practice A bounce dive to 30 meters is still a 30 meter dive in any model that I know of. And nobody assumes that your dive to 30 meters is a square profile with the entire bottom time spent at max depth.

 

If you can provide a reference to the legitimate authority which you are basing your argument (if that's what it is) that multiple bounce (or sawtooth) dives to depths of 30 meters or more do pose additional risks of DCS compared to an orthodox profile, then I and many others would be very interested to see it.

 

If you don't know of any reputable authority, then I would urge you to be very cautious about inventing your own decompression theory and/or rules for handling profiles and ascents, and to be doubly cautious about sharing your speculations with others who may not have the experience and knowledge to distinguish practical realism from dangerous nonsense. I just noted that your sig references a link to your logged dives since certification in 1978, totalling roughly 300 dives over the past 30 years, and roughly 100 dives over the past three years. The vast majority of your dives appear to be limited to depths of 11-15 meters, and there are only a handful of dives to 30 meters, none deeper. Nothing wrong with any of that, and it's nice to see that you've been diving for a long time, and not to be harsh, but I don't think 300 lifetime dives, mostly to less than18 meters, is the kind of experience that would make you an authority on what makes certain dive profiles safe or unsafe, do you?

 

I hope it's clear by now that this discussion wasn't really about you or your dive skills, and also that I really don't care what you and your buddy do or don't do, at any depth. Bounce up and down all day if you want. But if you really believe sawtooth dive profiles are not really dangerous under certain conditions that you believe you somehow have the knowledge and experience to figure out on your own, then I'm not sure I'd want to talk about it in a forum like this one, and definitely pas devant les enfants, ok?

Edited by frogfish

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I agree, it has gotten very much out of hand.

 

I do understand that the thread is about solo diving. I never made the thread about my diving skills. Please reread the post by ChristanG - here is a LINK. Tell me how is this about solo diving and not about my skills as a diver. How is it that ChristianG can make comments like that about me and it appears no-one cares but I react and I'm the bad guy?

 

Note that I am not suggesting you or anyone other than ChristianG was making comments about my diving skills.

 

Perhaps my choice of words about "full dive" were not the best. When I was talking about a "full dive" I was thinking about a dive where you do the dive you planned and your dive time/bottom time approaches the no-decompression limits. In these dives, you will be approaching full saturation when you surface - although being conservative, you should still be some way away from being fully saturated, but you will still have a lot of residual nitrogen.

 

We both know that the amount residual nitrogen left in our bodies after a dive will be dependent on both the depth of the dive and the duration of the dive. Even though we can't measure it, we know that you will have much more residual nitrogen after a 20 minute dive to 30 metres versus a 20 minute dive to 16 metres or a 10 minute dive to 30 meters. We also know that the residual nitrogen will leave our bodies over time when back at the surface and so the longer the surface interval, the less residual nitrogen.

 

I learned to dive long before there were dive computers and we planned our dives using dive tables. Using those tables, I could do a 30 metre dive for 20 minutes including safety stop, surface, have a 10 minute surface interval and still do a 30 metre dive for 3 minutes. I wouldn't do it, but I'm illustrating the point. Note that I'm not assuming a square profile here (or below), but that the maximum depth of the dive was 30 metres and the total dive time was 20 minutes.

 

Now, let's say (on a completely different day) I had only been at 30 metres for 3 minutes before surfacing (without a safety stop - yes I know bad, but I'm illustrating a point), the dive time would be around 8 minutes. That would put me into group C. A 10 minute surface interval would not change the group, but I could still do a 12 minute dive to 30 metres or a 32 minute dive to 20 metres and still stay within the no-decompression limits. This is all based on the DSAT Recreational Dive Planner (Copyright © 1985, 1987, 1988 Diving Science & Technology Corp).

 

Again, I'm using the above to demonstrate the principles I'm talking about, not to recommend to anyone they try these bounce dives. I never professed to be an authority on anything. I was merely participating in a discussion.

 

With regards to my dive log, I guessed you missed the note at the top. Unfortunately, my records are incomplete for the period from late 1980 through to 1998. I lost my dive logs when I moved house in 1998 and have only been able to include those dives where I took photos (as I still have my photography logs). You can probably add 100-200 dives for that period. But I guess 400-500 logged dives is still too few for me to participate in this discussion, which is sad.

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In reply to John's comments re disclaimers - they don't necessarily mean anything as far as I am aware - so failing to adhere to 'accepted practice' (ie surfacing after losing a buddy) may not be such a good idea depending on circumstances.

 

Experience should, but does not always, mean a greater level of understanding of diving procedure, theory and better diving practice. The British Sub-Aqua Club carries out an annual report of diving 'incidents' and from memory found no distinction between experienced and novice divers with regard to their incidents. This link may be of interest: http://www.bsac.org/page/544/diving-incidents.htm

 

Good diving practice is just that whether solo or buddy diving - I dive benignly as far as possible (some dives are simply not that benign!) on the basis that I want to continue diving and taking photos as long as I can. No photo is worth dying for!

 

Sadly, not all responses APPEAR to be as good humuoured as they could be on web fora - whether they intend to be or not. It is all too easy to come across harshly when no offence is intended in a short typed memo as here. I try to believe that web fora are about sharing useful knowledge and discussing topics usefully but this isn't always the case.

 

And excess knowledge can be a bad thing believe it or not. I researched a piece on a local dive blackspot (22 deaths in 11 years so far) to discover that divers were hitting 100m on air - because they knew this to be a possible though clearly dangerous practice through published information (correct or otherwise) which showed that some divers can do so. When saftey is concerned, read responses then check them - its not like photography - you can't try again if you get it wrong!

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I agree, best for us all to calm down, ATJ. I can see where you you might have taken Christian's comments amiss, but I doubt they were intended to offend. The reality is that we all have our hot buttons when it comes to safety. I see red when I run into McPADI divers who seem to think buddy diving was something decreed to Moses on Mount Sinai and that solo divers are somehow kin of Satan and Beelzebub, or who think that a snorkel strapped to the head is an essential piece of equipment but an SMB isn't. And, as you my have gathered, I'm concerned that a lot of divers don't seem to understand how risky certain kinds of profiles can be, and how it's probably impossible to figure out exactly where the dividing line between practical realism and suicidal stupidity really is.

 

Then I have to question myself - have I done any reverse profile dives in the past year, six months, or three months? The answer, I confess, is yes. Have I done dives with shorter than optimum surface intervals? The anwer, again, is yes.

 

About the only things I can say in my defense would be that, (1) I was aware that I was taking additional risk and I took further steps to try to compensate for that, and (2) beyond admitting the fact here, in this message, I haven't publicized the fact that I've done those dives (and they were exceptions to my standard practice, made for very specific reasons), and I certainly haven't publicly advocated reverse profiles or reduced surface intervals in this or any other forum as safe. I know that they aren't, and that if I'd been injured as a result of those divers, it would have been completely my fault, all the way.

 

Other people, on the other hand, get excited by different kinds of divers "sins", and may feel as strongly about my "same ocean same day" buddy diving philosophy as I do about carrying SMBs and diving "bend me" profiles. PGK made a lot of good points.

 

I wouldn't begin to suggest that you shouldn't or can't participate in this discussion, ATJ. But I do feel that divers ( like you or I) should be cautious about discussing practices that depart from well founded principles of safe diving (and you know that I don't mean "McPADI rules) in ways that could lead, or mislead, beginning divers to take on risks that neither they nor we fully understand. OK?

 

Frogfish

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The argument that no-one should disclose that they depart from 'normal' diving procedures (as in solo diving) because an ill-informed novice might take a lead is often used but ill-founded. The fatality I referred to was an inexperienced diver who took in a digital camera against my advice and (in my opinion) died 'getting just one more picture', leaving his group to do so and inadvertently diving solo, running out of air and failing to provide positive buoyancy for himself once he made the surface.

Therefore the corollary should be that this web-site should not encourage people to undertake photography while diving because they might do so before their diving skills were adequate and therefore put their lives at risk. Ban Wetpixel!

 

Internet discussions are exactly that. Let the buyer beware!

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I have to admit I still use the pop up and look for your buddy, then resubmerge also. But then I only use it on dives around 6-8 meter max.

 

i am sure they werent to offend:

 

Christian may not remember but when i was flamed as a newbie on the techdive list, he did his best by a personal email to explain the actions of others and basically told me not to worry too much about it.

 

Gerard

Edited by Cerianthus

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I would have thought that buddy diving was a well founded principle of safe diving and as such this whole thread is about departing from that.

 

I don't believe I was at all supporting practices that depart from well founded principles. On the contrary, I was trying to caution against departing from them.

 

My discussion about "full dives", while obviously poorly worded, was based on Repetitive Diving 101. Duration of the initial and subsequent dives is just as important as depth and surface interval. I was asked whether I would do a second dive to 30 metres after a surface interval of only 10 minutes. It is unlikely I would, but the duration of the initial dive, the planned duration of the second dive and the reason for the second dive might be enough to persuade me if I believed it was safe to do it. Would people consider doing two dives to 18 metres with a surface interval of 1.5 hours? I'm sure many people would, but if the duration of the first dive was 56 minutes you would be in a worse pressure group than after an 8 minute dive to 30 metres with only a 10 minute surface interval (or in fact no interval).

 

As already mentioned, we all have our own hot buttons. One of mine is inappropriate generalisations. Another is throwing away good concepts or procedures simply because they have some flaws. The latter seems to be very common in all fields, not just diving. Just look at Wile E. Coyote. He has some great ideas but gives up on them because they don't work the first time.

 

I agree that buddy diving is not perfect. I also agree that it is not mandatory for safe diving. However, there are some great benefits to buddy diving and if done properly can not only reduce the risks involved in diving but make a dive more enjoyable. I love the fact that I can hand by camera to my buddy if I want to use both my hands - yes I can get by without him, but it is much easier with him there. I can also hold his camera. Granted we are engrossed in our picture taking and so may not be as attentive buddies as we should be, but that doesn't mean that having a buddy is a bad idea. Granted surface searches from 30 metres are a bad idea, but that doesn't mean there aren't other benefits from having a buddy with you at 30 metres. There are other aspects of buddy diving that may not be ideal but that doesn't mean buddy diving is wrong.

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"... we made it a rule never to go down alone." The Silent World, J Y Cousteau 1958.

 

"For twenty years I have been trying to get rid of cables in undersea research. The Aqua-Lung rejected the air hose, lifeline and signal cord of compressed air diving" The Living World, J Y Cousteau 1963.

 

Two long established as well as well founded principles! But isn't health and safety a funny concept? The first indicates that Cousteau saw a need to avoid solo diving (although read his books fully and you will find that it appears that was a rule apparently not always adhered to) and one which has been accepted as the 'buddy' system by training organisations since, and the second is that carrying an independant air source negated the restrictive need for tethers, but despite this, somewhat bafflingly, some safety organisations still believe that diving on a line or with a buoy is the safest option (my own pet hate).

 

No doubt the debate over the acceptability of solo diving will continue but my two pennyworth is that I'd prefer to actually not have any rules set in stone! The trouble is that whenever anyone gets things wrong or makes a mistake and pays the ultimate price, the general media is up in arms and we all suffer as restrictive rules are then enforced.

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I would always prefer to dive with a retinue of servants. However, they often seem to become unpredictable once underwater! Is it because I don't pay them enough?

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I am sure they werent to offend:

 

Christian may not remember but when i was flamed as a newbie on the techdive list, he did his best by a personal email to explain the actions of others and basically told me not to worry too much about it.

Hi Gerard,

 

Thanks for the faith you show in me and, yes, I think I remember that occasion (that was one looooong time ago). It's GW, from the Nederlands, isn't it?

 

I often felt sorry for newcomers to the Techdiver list because those guys simply took NO prisoners and turned flaming into an art form. Nevertheless I learned a lot there and am sorry that it has died, or rather morphed into the GUE Forums.

 

Cheers,

 

Christian

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