Learned Wrong...

[Akimbo]

…That speaks more to the folks that you have seen diving than it does to reality. In the old days almost every diver was ended OOA, with with a CESA, a gentle, controlled, slow ascent to the surface...

For the benefit of others reading this, a little perspective is in order: The use of SPGs weren’t wide-spread until the mid-1960s to the early-1970s. There were marginally effective reserve or J-valves, but were in the minority and all but the inexperienced and ill-trained actually depended on them. A fully-instrumented diver had a depth gauge, compass, and a watch.

There are at least two reasonable questions from the perspective of recently trained divers:

“How come you old farts aren’t all dead?” and “How did you make it to the surface alive?”.​

Here’s how it works. Somewhere around 300-400 PSI the unbalanced regulators of the day began to develop noticeably increased inhalation resistance. It you had a reserve, you would pull the lever, all too often to find it down already — especially if you were a California kelp diver and still had a pull-rod on it. No problem, dive over, time to surface. I don’t ever remember surfacing under distress or concern over not making it, even from 120'. Obviously, we planned for decompression dives much more aggressively.

Thus Thal’s comment about all dives ending with a CESA. Perhaps it will also help to understand why we were never indoctrinated into thinking that the procedure is deadly.

This technique is riskier with today’s high-performance balanced regulators because your first sense of low supply pressure is pretty close to the IP (Intermediate Pressure), usually around 135 PSI. As a result, the 20-60 breaths on unbalanced regulators are closer to 2-4.

In light of that, every diver should intentionally experience running out of air under controlled conditions. That can start with breathing down what’s left after a dive while sitting on the beach. At that point, repeat in a swimming pool shallow enough to stand up. Just remember that what is left at depth can be even less. Your familiarity with the sensation can be the difference between a comfortable CESA and one that is somewhere between really scary and unsuccessful.

 

[Akimbo]

The reason EBSA is not taught at the recreational level is liability. The agencies decided it presented too much of a risk ... so they dropped it from the curriculum. And if an instructor adds it to their course and a student gets injured, the instructor's insurance will claim they were not following standards, and the instructor will be hung out to dry…

That is fair enough in such a litigious society as the US, but seriously wrong-headed. This is truly a case of allowing lawyers and bean-counters to put [-]safety ahead of contingent liabilities[/-] contingent liabilities ahead of safety. Unfortunately, well intentioned instructors are the ones with your hands tied.

… One cannot rightly compare recreational training to Navy training ... because if a Navy diver gets bent he steps out of his rig and into a shipboard hyperbaric chamber. Recreational scuba instructors don't have on-site chambers for students who mess up. Or if a Navy diver gets killed or injured, it's considered part of the job ... and the government foots the bill for whatever compensation that person's survivors is due. Recreational instructors don't have the financial resources the government does to assume that liability…

That is far from the practical truth. If a working Navy diver gets killed or injured it often costs a couple of careers after an investigation that is far more rigorous than in unlitigated civilian cases. Admirals haven’t authorized all the money that has been poured into research, safety, and training for divers to be treated as consumables. Don’t think for a minute that dramatizations in movies are accurate.

Chambers are not required for normal Scuba-based operations. See Page 6-40, section 6-8.9.4

…Like it or not, we are not training Navy divers. Nor are we any longer training people using protocols from the '70's. One can argue that we should .. but that's not germane to the reality of what we do. …

This is a fair assessment and I agree, but I don’t accept settling for it or that it is even remotely a sound compromise. For the benefit of those who have not read this and to continue my lobbying effort to improve things:

Anytime a course of any kind is developed there is a dumbing down relative to those who innovated, pioneered, and/or cobbled diverse information sources together. That can be a great thing and I absolutely benefitted from it throughout my life. It is a good thing that first grade arithmetic classes are dumbed-down or even the future Einsteins wouldn’t see second grade.

The place where funning-up and dumbing-down collide is when the same simplifications that are essential in first grade prevail through calculus. I have seen diving students told “never stop breathing” in order to forgo decidedly un-fun aspects of barotrauma. I appreciate that telling diving students that “holding their breath on ascent will cause their lungs to explode in their chest and you will die a horrible death” is bad for business. Unfortunately, the rule of “never stop breathing” seems easily forgotten in minor emergencies.

A similar collision occurs in the compromise between swimming tests suitable for BUD/S (Basic Underwater Demolition/SEAL) training and no swim test at all. After all, anyone with functioning limbs can swim with fins. The problem is fins make many functional non-swimmers deathly afraid of a loose fin strap and they enter the water primed for panic, as-in half their brain left onshore.

I didn’t go through harassment dives in my initial Scuba training, but was a much better diver after them in Navy Scuba school (also nothing like BUD/S). I am not suggesting incorporating them into recreational training but I believe that funning-up has gone too far resulting in divers that are fundamentally uncomfortable and leave the sport. I increasingly believe that the industry would be better off making the basic diving course include Open Water, Deep Water, and Nitrox; partly for the depth of knowledge and partly for the time in and out of the water for a lot of important stuff to sink in.

I believe the industry needs lessons for dive shops on selling a more expensive diving course rather than depend on sales gimmicks more akin to drug dealers. Every instructor I have ever met would be much happier if they did. Another missing piece is well produced training videos that make a lot of boring and dry crap interesting and memorable. Not just "talking heads" with a few primitive illustrations and props.

Honestly, I believe everyone here has the best of intensions even though I find some of the statements ill-informed or technically unsupportable. What may come across as personal attacks in the heat of debate are more a reflection of the passion and importance of the subject.

 

[Akimbo]

…That's why I have a standing offer to all of my students that if they ever drop their belt and lead ... I'll buy them a new one.

:yelclap: :wow: :worship: :thumbs-up: :cool3:


For freedivers, here is an offer that is also a class act: MAKO Spearguns: Ditching Your “Tin Man Pinch Weights” - Spearboard Spearfishing Community

 

[Thalassamania]

That is such a class act that I want to post the actual offer:

Dear Spearos,

As many of you know, Jeff DeRocher (aka Tin Man) designed the “Tin Man Pinch Weights”. Because Tin Man was busy with other commitments, he entrusted MAKO Spearguns with the manufacturing, sales and customer support for his invention and we were quite honored to do so.

Prior to this relationship with MAKO Spearguns, Tin Man made the following offer to any customer using his “Tin Man Pinch Weights”:

If you ever have to ditch your pinch weights in an honest dive emergency, I will replace them at half price. But there is a catch. You have to post the story for all of us to learn from.

Recently, I was asked if MAKO Spearguns would honor this same offer. In continuing Jeff’s unwavering trust and his commitment the dive community, MAKO Spearguns will gladly continue this replacement offer. Additionally, if you were wearing a MAKO weight belt, the same offer will apply.

In a true emergency, you should not be thinking about the cost of ditching.
Just ditch.

Thanks guys for taking time to read this. And thanks again Jeff for entrusting us with such a fine product.

Dive safe,
dano

I need about 20 lbs of new weights, I think I'm gonna go look for Tim's.

 

[Akimbo]

A Word of Caution​

The convention for practicing any type of emergency ascent is to perform them at the very beginning of your diving day. You don’t have to be a hyperbaric scientist to figure out why making them on a reped or when your computer is in the yellow zone is imprudent. Unless you are practicing in less than 10 Meters/30' I would suggest limiting practice runs to one or two per day.

 

[Akimbo]

That is such a class act that I want to post the actual offer:...
I need about 20 lbs of new weights, I think I'm gonna go look for Tim's.

The "Pinch Weights" are designed for rubber belts and work really well.

 

[Thalassamania]

Rubber's what I use.

 

[MXGratefulDiver]

We have dive shops here who have a similar standing offer. But because so many of our divers are in heavy wetsuits, or drysuits with 400G undergarments, it's not uncommon for them to be wearing 30+ lbs of lead ... and the reality is I've seen divers here with 40+ or more. That's going to make you more than just a little bit buoyant.

What we train and encourage is to swim up, and drop your weights once you're on the surface ... so you don't have to struggle to remain there.

I once recovered a 35# weightbelt that a (presumably) experienced diver ditched from about 80 feet at one of our local dive sites. The diver who ditched it required hyperbaric treatments ...

... Bob (Grateful Diver)

 

[Akimbo]

…"If you are confused or panicked and there is doubt about which ascent to use, ditch the weights and do a buoyant ascent."

Anyone care to guess the source and date of this quote?

Is using Google cheating?
http://www.scubaboard.com/forums/q-...ssi-emergency-ooa-procedures.html#post4953492

Scuba Flashcards

http://www.scubaboard.com/forums/new-divers-those-considering-diving/25765-dropping-weights.html

 

[Akimbo]

…I once recovered a 35# weightbelt that a (presumably) experienced diver ditched from about 80 feet at one of our local dive sites. The diver who ditched it required hyperbaric treatments ...

Two comments and a question:
Do you know if it was intended as a decompression dive?

Better to find the belt on the bottom than on a corpse.

I find 35 Lbs is a lot of lead have on my hips, to handle, or jettison. I try to keep my belt at or below 10 KG/22 Lbs for all these reasons. Above that, something like the DUI Weight & Trim System is worth considering due to the shoulder straps, the 40 Lb capacity, and the ability to drop half at a time. I saw a diver pull one weight pack at a time and hand it up to the boat to lighten his load climbing the ladder. They are a little bit of a hassle to reload though.