dive to 300 ft

[Akimbo]

danvolker, are you saying that Gilliam doesn’t understand the DIR principles or simply doesn’t accept all the dogma? How is a world record different than a dive to 300' without an objective beyond sightseeing?

Understand you are having this conversation with a guy who isn’t going to 300' without trying to recover something valuable or being paid. I certainly don’t understand how going to 300' for any length of time without a chamber on deck, and preferably a bell, is anything but reckless — let alone doing anything right.

 

[boulderjohn]

danvolker, are you saying that Gilliam doesn’t understand the DIR principles or simply doesn’t accept all the dogma? How is a world record different than a dive to 300' without an objective beyond sightseeing?

DIR is a set of principles, and if one does not accept them, then one is not DIR. It really is that simple. That does not mean people who are not DIR divers are not doing significant dives, it just means they do not accept the DIR principles and are not DIR.

 

[rongoodman]

I haven't met either of the two gentlemen, but I have both DIR and TDI training. I noted with some amusement quotations in the 9-year old TDI trimix text statements that looked to me to be not only anti-DIR but specifically aimed at George as well. Interestingly enough, the 7-year old Advanced Trimix book comes much closer to DIR in approach and contains none of the confrontational language.

I caught some too. I'm looking forward to seeing the rewrite(any day now, I hear....).

 

[danvolker]

danvolker, are you saying that Gilliam doesn’t understand the DIR principles or simply doesn’t accept all the dogma? How is a world record different than a dive to 300' without an objective beyond sightseeing?

Again, 500 feet on air is seeing how many bottles of Tequila you can chug, without dropping dead...keep adding bottles, it will poison you to death eventually.
Every WKPP push had massive amounts of gas stored all along the dive, and tox was never an issue, AND, stupid drunk/narced was never an issue..... I see zero similarity.


300 feet on trimix with doubles and a deco bottle is as easy for many of us as a 30 foot dive is for the typical AOW diver. It just takes longer to load all your gear on the the boat

300 feet on air, now that we know better, and considering how trimix is easily available.....is just stupid.

 

[Slamfire]

He is correct and you are not. You might want to check your numbers.

I don''t think our discussion was to try to figure out who's wrong or right. I don't really think it's a big deal to breath 10% O2 for a minute or less. It's not a big deal to hold your breath for a minute, it would be less of a big deal to breath 10% from surface to 1.6 ATAs. I gave 2 ATA initally because it's an easy target -- 33 ft, 10 m or 0.2 ppO2 -- which is well within normoxic.

Jeff, my comment was to try to explain, within my limited knowledge, why it's ok for Brian to not use any travel gas. And I was trying to explain in order to verify that I'm understanding things correctly.

As abrasive as Brian often is, there's good, valid logic on some of the stuff he writes. It's just a matter of looking beyond the emotionally, abrasive tone in order to rescue something of worth. Not everything has to be an emotional and confrontational urinating contest that quickly departs from logic.

 

[JeffG]

within my limited knowledge

I agree

 

[PfcAJ]

I don''t think our discussion was to try to figure out who's wrong or right. I don't really think it's a big deal to breath 10% O2 for a minute or less. It's not a big deal to hold your breath for a minute, it would be less of a big deal to breath 10% from surface to 1.6 ATAs. I gave 2 ATA initally because it's an easy target -- 33 ft, 10 m or 0.2 ppO2 -- which is well within normoxic.

Jeff, my comment was to try to explain, within my limited knowledge, why it's ok for Brian to not use any travel gas. And I was trying to explain in order to verify that I'm understanding things correctly.

As abrasive as Brian often is, there's good, valid logic on some of the stuff he writes. It's just a matter of looking beyond the emotionally, abrasive tone in order to rescue something of worth. Not everything has to be an emotional and confrontational urinating contest that quickly departs from logic.

Its usually not a problem to breath hypoxic gases on the surface for a very short time. The issue comes if something delays your descent and you're breathing it (10-12% o2) for an extended period. A similar (but much more complicated) thing happened that nearly killed a friend of mine. Hypoxic gases certainly deserve respect.

 

[gsk3]

It's not a big deal to hold your breath for a minute, it would be less of a big deal to breath 10% from surface to 1.6 ATAs.

The analogy doesn't hold. You can hold your breath for a while because you store oxygen in your lungs. If you are ventilating deeply and thoroughly on a hypoxic mix, you are replacing that slightly used air with...hypoxic mix (much lower O2). So you will lose consciousness much sooner.

This is not a comment about the practical aspects of breathing a hypoxic mix on the surface...on that I defer to the many people who have actually done it.

 

[PfcAJ]

Here's a neat video showing how nutty hypoxia can be. The last few minutes are pertinent to this discussion
Part 4 - How to Kill a Human Being - BBC Horizon - YouTube

 

[Slamfire]

I agree

I'm glad we can agree on something. One day, when I grow up, I wanna be like you and have access to the fountain of unlimited knowledge.

AJ and gsk3, your warnings fuzzing around inhaling hypoxic gas at surface are well received. Getting down to 1.6 ATA's on a breath hold may be safer than breathing 10% O2 at the surface. If for any unforeseen reason you find you need to take a breath before you get to 1.6 ATA's then you might want to start breathing out of the 35/25 bottle, and not out of the 10/70 bottle. After all, being kept there by an unforseen situation might mean you have to remain there longer than comfortable for 10/70. Once you start inhaling hypoxic you are on a short countdown to snoozing time or maybe even the afterlife.

So what is proper DIR procedure for a dive like this? Breath hold initial descent, one or two breaths of hypoxic 10/70, or using 35/25 as a travel mix?