Is Deep Air / Light Deco (bounce?) Discussible on ScubaBoard?

[MXGratefulDiver]

I am guessing that you just copied his definition of bounce diving.

Depends on the definition of "light deco" I suppose. To me that would be a deco obligation that can be cleared by making a moderately controlled ascent with a few minutes in the shallows ...

... Bob (Grateful Diver)

 

[MXGratefulDiver]

It's a risky dive profile, but single AL80 deep air bounce dives are done safely every day, we all know this.

Semantics, perhaps ... but I wouldn't say they're done safely ... I'd say they're done riskily, but without incident.

The "non-point" many of you are trying to make is whether to endorce or teach such a dive. I don't. But, what other divers do, divers do...

I have spent the past 35 years writing manuals for a living. The first rule of writing is "know your audience". Halemano has spent a great deal of effort trying to establish himself as a "spokesman for the masses" of recreational diving worldwide ... so that would make his audience somewhat inexperienced, poorly trained divers who generally don't dive without supervision.

I would agree that what other divers do, divers do ... but to endorse deep dives and light deco for divers who typically don't even have the capability of planning their own dives strikes me as rather irresponsible. Most of those "masses" he presumes to speak for can go through an AL80 rather quickly on a 20M reef dive ... imagine what they'd do below 40M.

... Bob (Grateful Diver)

 

[boulderjohn]

In order to try to clear up the confusion, I would like to repeat my list of questions with some minor refinements. In his first reply, Halemano did not have any answers--he said he just wanted a conversation about the topic. I hope he defines the topic he wants to discuss enough so that we can get a clear idea of what we are talking about.

I really want VooDooGasMan to respond to this we well. I think I have a pretty clear idea based on his many posts in many threads, but I would like to be sure, and I think others who have not seen those other posts would like to know as well.

1. What depth limits do you have for diving on air?

2. I have read over an over again in this thread that it is not for beginners. How much experience does a basic OW diver need to have, and what kind of experience should that be?

3. How does a diver determine how much air is needed for a dive?

4. At what level of remaining gas should a diver begin an ascent?

5. Is there any need for redundancy? Is one tank enough?

6. What protocols do you use for determining a decompression profile?

7. What training is needed to be sure one can handle emergencies at depth? (For example, it is very common in technical diving training to find dives losing buoyancy control when first practicing OOA scenarios, so there is training for that. Even when I was working on my full cave certification, the instructor always did the OOA drills in a place with a low ceiling because of the tendency to ascend.)

8. Is any special equipment needed, or is a standard OW rig just fine? (For example, are DSMBs encouraged, and, if so, is deploying them at depth part of the expected training?)

9. Do you have a standard limit for PPO2?

 

[dumpsterDiver]

In order to try to clear up the confusion, I would like to repeat my list of questions with some minor refinements. In his first reply, Halemano did not have any answers--he said he just wanted a conversation about the topic. I hope he defines the topic he wants to discuss enough so that we can get a clear idea of what we are talking about.

I really want VooDooGasMan to respond to this we well. I think I have a pretty clear idea based on his many posts in many threads, but I would like to be sure, and I think others who have not seen those other posts would like to know as well.

1. What depth limits do you have for diving on air?

2. I have read over an over again in this thread that it is not for beginners. How much experience does a basic OW diver need to have, and what kind of experience should that be?

3. How does a diver determine how much air is needed for a dive?

4. At what level of remaining gas should a diver begin an ascent?

5. Is there any need for redundancy? Is one tank enough?

6. What protocols do you use for determining a decompression profile?

7. What training is needed to be sure one can handle emergencies at depth? (For example, it is very common in technical diving training to find dives losing buoyancy control when first practicing OOA scenarios, so there is training for that. Even when I was working on my full cave certification, the instructor always did the OOA drills in a place with a low ceiling because of the tendency to ascend.)

8. Is any special equipment needed, or is a standard OW rig just fine? (For example, are DSMBs encouraged, and, if so, is deploying them at depth part of the expected training?)

9. Do you have a standard limit for PPO2?

Those are all the important aspects that need to be addressed, to potentially be capable of pulling off a reasonably "safe" deep air dive. So you want a manual of deep air diving?????


Each one of those topics, probably has a range of potential answers or solutions,, like how deep?

It's all well and good, but the individual variations in narcosis between people makes it impossible to provide some hard and fast "rules". Some much of the dangers of deep air relate primarily to depth/narcosis that it becomes a very PERSONAL judgment call to determine what is an acceptable risk for any particular recreational diver.

Clearly "deep air" encompasses a depth range extending from slightly past 130 all the way to the near suicidal depths of say past 350 feet. For any discussion to be "adult", people need to be careful not to take certain statements out of (depth) context. For example, if someone feels they can handle a PP O2 of 1.8.. doesn't mean that they are arguing that an exposure of 2.4 is OK as well.

People have to make REASONABLE decisions about these kinds of dives.

They also have to recognize that at depths where the oxygen exposure becomes a meaningful concern, the "defensibility" of the practice of "deep air" becomes drastically reduced.

 

[Moonglow]

Semantics, perhaps ... but I wouldn't say they're done safely ... I'd say they're done riskily, but without incident.

... Bob (Grateful Diver)

Semantics matter in instruction-- distinction with a difference. All dives incure risk; managing risk has improved greatly due to of the advancements of equipment, knowledge, and math concerning diving over the last 40 years.

Deep air diving is "ole' school" for sure, but it's the option for many who don't have instruction/certifications, access to the lastest equipment and helium. Still, one can find agency instruction in "narcosis management". Hal Watts has been teaching it seemingly forever. He made his last professional dive to the bottom of 40 Fathoms on air at the age of 84. Scarlett Watts, his daughter, went to 425 fsw in 1999.

For those who are interested:

PSAI Technical and Extended Range Programs.

 

[boulderjohn]

Those are all the important aspects that need to be addressed, to potentially be capable of pulling off a reasonably "safe" deep air dive. So you want a manual of deep air diving?????

OK, let's try to folow this carefully. I seem to be having some trouble communicating effectively.

As I have said about three times in this thread already, I have a manual for deep air diving--TDI's. It is about 8 inches from my left elbow at this point. I am trying to get the definition for deep air BOUNCE diving that VDGM and others are raving about without providing any real definitions.

And I can answer every one of those questions for myself. I am trying to get THEIR definitions.

 

[boulderjohn]

Semantics matter in instruction-- distinction with a difference. All dives incure risk; managing risk has improved greatly due to of the advancements of equipment, knowledge, and math concerning diving over the last 40 years.

Deep air diving is "ole' school" for sure, but it's the option for many who don't have instruction/certifications, access to the lastest equipment and helium. Still, one can find agency instruction in "narcosis management". Hall Watts has been teaching it seemingly forever. He made his last professional dive to the bottom of 40 Fathoms on air at the age of 84. Scarlett Hall, his daughter, went to 425 fsw in 1999.

For those who are interested:

PSAI Technical and Extended Range Programs.

Once again, I am confused. The point of the thread is to introduce a discussion about a diving practice that is NOT endorsed by any agency. Taht is why such discussions are not allowed on SB right now, and the OP wanted to change it. If the OP wanted to talk about the PSAI or TDI deep air programs, there would be no prohibition and no need for this thread at all.

 

[dumpsterDiver]

OK, let's try to folow this carefully. I seem to be having some trouble communicating effectively.



As I have said about three times in this thread already, I have a manual for deep air diving--TDI's. It is about 8 inches from my left elbow at this point. I am trying to get the definition for deep air BOUNCE diving that VDGM and others are raving about without providing any real definitions.

And I can answer every one of those questions for myself. I am trying to get THEIR definitions.

I seriously, ought to read one of those books....

 

[gsk3]

Well Steve, you (with the 33,600+ posts) "should try diving sometime" with locals in New Jersey or Key West who dive wrecks below 130ft on air every day-- then you will no longer be scared of it.

It's funny, but I know a good number of NJ wreck divers, and all the ones I know took AN/DP if they dive below 130ft on air. That's "technical" training if you're keeping score. In fact, all of the dive boats that I know of (and boats are the only way to get deep out here unless you own your own) demand redundant gas supplies even on 100ft dives. Why? Most of them have seen a few too many problems. Try calling a NJ boat and asking to sign up for a 150ft dive without technical training. Please record the laughter that will follow.

Now since the deep air advocates in this thread (Thal excepted) have carefully avoided defining what they mean by a deep air dive, it may be that that's what you mean. But judging by the number of times e.g. Jax and boulderjohn have brought up AN/DP and the response was "conspiracy blah blah technical is evil," I'm guessing AN/DP is not what you had in mind.

Thal - I have no idea why you're throwing your hat into the ring here. In my mind, this is an argument about getting formal training in a system which provides significant safeguards vs. just doing bounce dives deep with no training because "people do it every day." Yours clearly falls in the former camp.

 

[Thalassamania]

I have serious problems and concerns with the semantics of this thread. A bounce dive can be shallow or deep, a single short deep dive is not (in my world) a bounce dive, if there are two in quick succession, the second, however, is.

I'll make a stab at John's questions:

1. What depth limits do you have for diving on air? 190 fsw

2. I have read over an over again in this thread that it is not for beginners. How much experience does a basic OW diver need to have, and what kind of experience should that be? I'd say on the order of 100, progressively deeper dives.

3. How does a diver determine how much air is needed for a dive? Descent: 60 FPM, calculate time and use 1/2 depth for gas use calculation; Bottom: normal calculation; Ascent: 30 FPM, so use twice descent, add 1 minute at 1/2 dive depth, add time for any stops, double the gas needed for ascent. This is the standard package. Now, the contingency package ... do the same thing for 10 feet deep and 5 minutes longer. Bingo Air is the gas required by the diver in the contingency package times two (or adjusted for a difference in the buddy's SAC rate).

4. At what level of remaining gas should a diver begin an ascent? Bingo air is the diver and buddy's combined contingency package.

5. Is there any need for redundancy? Is one tank enough? Depends on the tank, do I have to dive doubles, no, but I likely need a 100 cubic foot tank. Should I use a slingshot valve and two regs, at a minimum ... only if I plan to do deco in the standard package.

6. What protocols do you use for determining a decompression profile? U.S. Navy Standard Air Tables.

7. What training is needed to be sure one can handle emergencies at depth? (For example, it is very common in technical diving training to find dives losing buoyancy control when first practicing OOA scenarios, so there is training for that. Even when I was working on my full cave certification, the instructor always did the OOA drills in a place with a low ceiling because of the tendency to ascend.) I have not found this to be an issue. Divers who are preparing to do deeper diving with their standard rig have not issue, if they are switching to a larger tank, multiple regs or doubles, then we back up and they do valve drills combined with: doff and don, doff and don buddy-breathe, doff and don long hose share and then swim.

8. Is any special equipment needed, or is a standard OW rig just fine? (For example, are DSMBs encouraged, and, if so, is deploying them at depth part of the expected training?) For deep air, no-D, standard rig may be fine, depends on team SAC rate.

9. Do you have a standard limit for PPO2? At depth: 1.6, for Deco: 1.8.