The dangers of bailing?

[The Chairman]

First of all... none are holding their breath!

For those who don't get the joke... the diving world has a number of "rules" which at one time or another have been deemed incontrovertible. A mask on your forehead means you are in distress, people with nitrogen narcosis will offer their regs to a fish and of course: if you dive with split fins thou wilt surely die. One of the longest running rules is Rule #1: Never hold your breath. Like every rule, there are always exceptions... and this is no different.

But back on track... In the old days of J-valves, it was common to come to the end of your air and find (alack and alas) that you had already tripped your reserve and now your tank was dry. There was one dive where I did a CESA from below a 150 feet that I will never forget: but I didn't die. The surface air was exceptionally sweet that day and I began a rather long hiatus from diving.

 

[RonFrank]

The description provided is so vague it is impossible to understand the issue. Books may or may not be based on anything. Your post poorly describes a scenario, and then asks us to provide an answer.

So my answer is ......Maybe...

 

[Thalassamania]

OK, not holding their breath it is.

In the old days, after we met the criteria for a new depth bracket (30, 60, 100, 130, 150, 190) we had to make a free ascent from that depth. As part of getting my 150 ft card I had to do a free ascent from that depth. I realized that that was going to be fairly easy, that's just two pool lengths. The bitch was that we went out, dropped down, did the ascent, and then called it a day. The DSO would not let me dive again for 12 hours.

 

[DA Aquamaster]

A couple thoughts regarding various posts...

1) A diver at 110' could in fact be in a great deal of trouble in an OOA emergency.

For example with a 45 minute bottom time on 32% (a very realistic and even conservative schedule for a diver with 260 cu ft of back gas and a reasonable sac), the diver would now have a 20-25 minute accellerated deco schedule with his deco gas, but a much longer 45 minute deco obligation on back gas. If the diver has a catastrphic gas loss or delays on the bottom for any significant period of time, the curves for the decreasing gas remaining and the increasing gas required for the back gas deco, can quickly intersect - and then the diver will be faced with being OOG at some point and having to blow off deco to make a free ascent. A really bad day will then result.

2) Back in the day your suggested depth limits was twice your "skin diving" (freediving) limit - the idea being if you could swim down (for example) 75' on a breath held dive, you could then reasonably expect to ascend from 150'. It worked pretty well as it balanced swimming/freediving skills to your depth limit, and on the way up from depth, once you reached the half way point, you had a great deal of confidence as you'd been there before. In contrast, today many divers are really poor swimmers and few have any freediving experience.

3) I had a few "oops the J-valve has already been pulled" moments with some swimming ascents - but in that case, there is usually still some gas in the tank and you get a bit more on the way up. I don't think anyone at the time regarded it as an emergency (at least on a dive within the very generous at the time NDLs) but rather just a brain fart. Afterall, we were trained to do free ascents, this was just one reason why.

4) The one serious free ascent I had occurred from 90' under my boat. I was working under the boat for a fairly extended period after a dive and dropped a wrench. I chased it down (i.e no air in the wing, fully exhaling and swimming like mad to catch the wrench which stayed about a foot in front of my finger tips. At 90' I fully exhaled (to stay as negative as possible) and then attempted to inhale but got absolutley nothing from the reg - the downside of a high performance, balanced reg, combined with murphies law stating you won't suck the tank dry mid breathe when you'd notice it with gas in your lungs but rather after you exhaled everything. I had a Wile E. Coyote moment realizing I had no gas in the tank, no gas in my lungs, lots of negative buoyancy, some O2 debt and 90' of water above me. It's the only time I have dropped weight underwater (and a CO2 inflator would have been handy), but it was still surviveable as you still have a minute or so of usable O2 in your bloodstream and you will get another breath out of the tank on ascent from that depth - which is nicely timed as a cushion against shallow water blackout.

 

[MX727]

In the passage in question, the diver was on the San Diego. The sandy bottom was at 100'. He dumped all of his gear on the bottom. The coroner said he ruptured both lungs. I believe he held his breath on the ascent.

 

[tengsr]

people with nitrogen narcosis will offer their regs to a fish

I thought it was trying to play golf with a mud shark as a driver

 

[USVet96]

OK, not holding their breath it is.

In the old days, after we met the criteria for a new depth bracket (30, 60, 100, 130, 150, 190) we had to make a free ascent from that depth. As part of getting my 150 ft card I had to do a free ascent from that depth. I realized that that was going to be fairly easy, that's just two pool lengths. The bitch was that we went out, dropped down, did the ascent, and then called it a day. The DSO would not let me dive again for 12 hours.

You know I never really thought about it like that before, in that context, but you are right. I remember years ago swimming in a 50 meter pool and doing underwaters, up and back (mask and fins). We did not have gear on true, and there was no pressure, but the idea and concept of knowing that you are able to swim 100+ meters underwater on 1 breath of air is a nice reassurance.

I think one of the other posters hit the nail on the head. ALOT of the old school divers, and many other divers for that matter, learned to free dive, or are at a minimum good swimmers. At least in direct relation to ALOT of divers in gear today.

There is this INSANE IDEA that ALL agencies allow for some reason, where the divers being taught to dive today are NOT good swimmers at all. IMO there needs to be MORE training and emphasis strictly on the SWIMMING part.

Just my $.02

USVet

 

[DA Aquamaster]

You know I never really thought about it like that before, in that context, but you are right. I remember years ago swimming in a 50 meter pool and doing underwaters, up and back (mask and fins). We did not have gear on true, and there was no pressure, but the idea and concept of knowing that you are able to swim 100+ meters underwater on 1 breath of air is a nice reassurance.

I think one of the other posters hit the nail on the head. ALOT of the old school divers, and many other divers for that matter, learned to free dive, or are at a minimum good swimmers. At least in direct relation to ALOT of divers in gear today.

There is this INSANE IDEA that ALL agencies allow for some reason, where the divers being taught to dive today are NOT good swimmers at all. IMO there needs to be MORE training and emphasis strictly on the SWIMMING part.

Just my $.02

USVet

I noted a change in the late 1980's where it stopped being about diving and started being about the dive travel industry. The priority from that point forward was to dumb down the certain requirements in order to greatly increase the potential market. In my opinion it has created legions of DM guided reef tillers - but we still erroneously call them "divers". They aren't.

 

[Gilldiver]

I noted a change in the late 1980's where it stopped being about diving and started being about the dive travel industry. The priority from that point forward was to dumb down the certain requirements in order to greatly increase the potential market. In my opinion it has created legions of DM guided reef tillers - but we still erroneously call them "divers". They aren't.

That was also just about the time when you started getting certs for Dive Masters vs. just going with a dive guide. Dumb down the classes and you had to smarten up the guides to compensate.