Very high PPO2

[mello-yellow]

The cover article of the latest Sports Illustrated, "The Rapture of the Deep" is about Pipin and Audrey Ferreras, and about Audrey's fatal dive last October. Here is what caught my eye:

Audrey was trying to reach record 538 feet. A safety diver named Pascal Bernabe was at the bottom, and the next safety diver, Wiky Orjales, was at 295 feet. Five minutes and 45 seconds into the dive, Bernabe with unconscious Audrey reached 295 feet station and found Orjales already gone.

Quote: "So much time had elapsed that Wiky - who was on a very short time leash because he was breathing compressed air instead of Trimix Pascal was inhaling - figured the dive had been aborted, that Audrey had to be below sharing Pascal's mouthpiece. So he'd ascended."

At 295 feet the pressure is 10 ATA, and PPO2 is 2.1 ATA. What is the maximum exposure time for that? (My Nitrox table goes only as high as 1.6 ATA)

Not to be flippant, but if I were breathing air at 300 fsw, I too would be anxious to leave. Not that I ever would in the first place!

 

[Braunbehrens]

The risk of TOX at that PO2 is really high, no matter how long you stay. I don't know what the "recommendation" is, but TOX is a weird beast. Some people can take O2 at 60 ft for quite some time. Others can't. The weird thing is that it's not even consistent among one person. One day you'll be fine, the next day you'll tox after 10 mn.

In general I wouldn't be freaked out about toxicity in terms of drifting down a little during a deco stop, just go to backgas and go back up. But staying for any length of time at very high PO2's is just plain dumb (unless you're suicidal).

There is a famous article where a lot of the bigshots in diving go to extreme depths on air, and I belive it was Tom Mount who went to something like 400 ft on air and wrote something on a slate.

To me, going deep on air like this is about as smart as sitting down and seeing how much rat poison you can eat. There is no glory or honor in the accomplishment, just luck, stupidity, and a macho attitude that has no place in diving.

That's just my opinion of course....I don't mean to offend anyone.

 

[Padipro]

I'll have to look for that issue tomorrow as I'm cerouis to see if there is any mention as to what may have caused her death. I remember how quiet everyone involved was after it happened. I had the chance to meet both Pipin and Audrey the year before last at the Ocean Fest here in Ft. Lauderdale. I was impressed by both.

It doesn't sound to me like a very good safty team if divers can't stay at their assigned depths long enough to ensure a rescue. Why someone would be on air at such a great depth is beyond me, especially when Trimix seems to have been available. Is it possible that the authors of the story got it wrong? You know how the media can be, someone is assigned to cover a story on a subject they know nothing about and they end up getting the facts all screwed up because they don't know the differance.

It will be interesting reading.

Scott

 

[Diver0001]

It can't be true. It sounds to me like a case of the press reporting what someone said to them without checking their facts first.

R..

Padipro once bubbled...
I'll have to look for that issue tomorrow as I'm cerouis to see if there is any mention as to what may have caused her death. I remember how quite everyone involved was after it happened. I had the chance to meet both Pipin and Audrey the year before last at the Ocean Fest here in Ft. Lauderdale. I was impressed by both.

It doesn't sound to me like a very good safty team if divers can't stay at their assigned depths long enough to ensure a rescue. Why someone would be on air at such a great depth is beyond me, especially when Trimix seems to have been available. Is it possible that the authors of the story got it wrong? You know how the media can be, someone is assigned to cover a story on a subject they know nothing about and they end up getting the facts all screwed up because they don't know the differance.

It will be interesting reading.

Scott

 

[BIGJC]

I am working from memory here so forgive me if I am a little off but the US Navy tables have a section called "extreme exposure" and it goes from 1.61 to 2.4 (I think).. anyway, I believe a 2.0 exposure can be tolerated for about 30 minutes without risk of seizure... Now, thats not a SUGGESTION to dive with that hot of a mix it is simply a plan for an emergency procedure. I know that commercial divers routinely decompress at a pPO2 of 2.0 but they are in a hard hat or a dry chamber when they are doing it.

so yes you can tolerate a high pPO2 for a short interval but it is for emergencies only and is certainly not for a safety diver!!!!

I personally have been to 200 on air and during the dive I had to STUDY my SPG to tell how much air I had left! Why do it if you don;t have to? thats how I feel about it, but some old timers and some of the less educated feel otherwise!
:boom:

 

[daylight]

Braunbehrens,
As I recall that Deep Dive fiasco was in the Bahamas and it wasn't Tom Mount but some other folks. Please verify your info.
I'm sure Quest can relate info.
Later,
Larry

 

[chrpai]

I think the above link refers to what you want.

 

[daylight]

Chrpai,
Thanks for the article. That's the article and the circumstances I recall and who the participants where. How that ever got twisted around to say that Tom was one of the fun-seekers is weird.
Dive Safe
Larry

 

[Braunbehrens]

daylight once bubbled...
Chrpai,
Thanks for the article. That's the article and the circumstances I recall and who the participants where. How that ever got twisted around to say that Tom was one of the fun-seekers is weird.
Dive Safe
Larry

Larry, sorry my original message wasn't more clear. I'm referring to two separate incidents. The one with Tom Mount is in his book, IIRC. He signed his name and did a math problem on a slate, and under where it says "dont' go any deeper " he wrote "no $|-|it!!"

 

[rcohn]

Diver0001 once bubbled...
It can't be true. It sounds to me like a case of the press reporting what someone said to them without checking their facts first.

No it sounds like it's in line with reports on the freedivelist shortly after the accident. The written IAFD safety protocols were apparently not followed.

Ralph