100% O2 @ 50 Fsw

[Curt Bowen]

Well I know the question was posed to Curt but for US Navy saturation diver the oxygen percentages are kept from .44 to .48 atmospheres absolute O2.

In emergency situations percentages up to .6 ata can be used but the exposure must be less than 24 hours.

In saturation diving percentages of signifigant concern is pulmonary O2 toxicity.

As far as the surface interval, that is why the maximum time from water stop to chamber stop is :05 minutes, if this time is exceeded or the diver has any symptom no matter how minor the decompression protocol is aborted and the diver is treated for decompression sickness (TT-5 or TT-6)


The water is the least desirable place to decompress the divers, especially on 100% O2. Evrything is about maximising the diver bottom time while minimizing decompression obligations, this is accomplished by decompressing the divers on 100% O2 on the surface in a controled (temperature, depth, gas percentage) environment.

Thanks for the answer, saved me a lot of time typing. And you being a commercial guy and I just a tech guy, you have allot more knowledge in this area.

 

[tndiveinstruct1]

The reporter got the chamber depth incorrect, all the decompression is at 40 FSW but other than that the statement is accurate.

Not disputing what you are saying Jeff, but the article for the link I posted was credited to Captain Chris Murray, Supervisor of Diving, Naval Sea Systems Command, U.S. Navy. I would suspect that before the good captain would put his name to the article, he would have given it a good read for accuracy.

Still, no matter what, an impressive job and my mask off to everyone that has been involved in that expedition.

Randy Cain

 

[rmediver2002]

Not disputing what you are saying Jeff, but the article for the link I posted was credited to Captain Chris Murray, Supervisor of Diving, Naval Sea Systems Command, U.S. Navy. I would suspect that before the good captain would put his name to the article, he would have given it a good read for accuracy.

Still, no matter what, an impressive job and my mask off to everyone that has been involved in that expedition.

Randy Cain

Randy the article you posted http://oceanexplorer.noaa.gov/explorations/monitor01/logs/jun30/sat_dive.html

is credited to Chris Murry but it is talking about the saturation portion of the project and never mentions the surface decompression diving?

Not really sure what you disagree with in my statement?

 

[rmediver2002]

Much of the work on the most recent Monitior project was completed by saturation divers. There was also many "sprint" diver diving on "surface decompression with oxygen" profiles (about :20 minutes of bottom time per dive)

For surface decompression with oxygen the divers will either do very short in water stops or on less strenuous tables no water stop.

The surface crew then has 3:30 minutes to undress the divers and get them into the chamber, the chamber is compressed to 40 feet sea water (equivilent depth) at a rate of 80 feet per minute :30 seconds max.)

The diver breathe 100% oxygen at this decompression stop but take a :05 minute air break for every :30 minutes of oxygen breathing (breathe air instead of 100% o2 - this time does not count towards the decompression obligation)

The reporter got the chamber depth incorrect, all the decompression is at 40 FSW but other than that the statement is accurate.

I responded to the thread as a whole although I clicked on your post (the last on in line at the time) the original question is about ppO2 during surface decompression using O2 (the sprint diver...) not saturation diving.

 

[tndiveinstruct1]

I responded to the thread as a whole although I clicked on your post (the last on in line at the time) the original question is about ppO2 during surface decompression using O2 (the sprint diver...) not saturation diving.

Yep that's it.

Sorry to hijack the thread Jim. Good points of discussion though everyone. I know for one thing I have learned a bit more about deco and physiology during this, and I hope that I have contributed in some meaningful fashion.

Randy

 

[jbd]

thanks you all for the great responses. SueMermaids post somewhat highlights part of my concern over the kind of information that is presented in these kind of programs. She and her finacee had much the same "reaction"(for lack of a better term right now). I have a more personal reason for being concerned about this which doesn't involve diving but did cost a friends life many years ago.

Thanks you all again for the informative posts. Gives me more to research and study up on as I prepare to move into technical diving.

 

[jbd]

When I was on the 2001 USS Monitor project, we assisted the surface supplied salvage divers with video and lighting.

You're killin' me Curt

rmediver2002--I need to do a dive with a helmet like in your avatar. Got any spares laying around

 

[cdennyb]

Since you had the benefit of reading both my posts; what is your point? What exactly made you think that I was going to do such a thing anyways? Until you know me well enough to understand my motives, don't prejudge and label me with childish, immature comments. It really doesn't become people our age.

A thousand pardons to you personally. Your question was interpreted as a general "what do you think about..." and I didn't really think you'd do anything like that yourself.
Since I now have the benefit of 20/20 hindsight and find many very qualified statements concerning this matter, I stand corrected and admonished severely. Just make sure you're all here when I stick my foot in my ear again!
My first thought 'off the cuff' was, "Stick to rec diving" because someone thinking about doing that sort of thing was heading down the road to eternity. The second part was a general answer as well.
I'll go stand in the corner now

db

:11: OH one more thing while I'm on the "chopping block" here. Why would you post a 'loaded' question/statement like that on this message board anyway. I think it might have received a different response if it had been posted on the DS board instead. Am I right?

 

[Charlie99]

Any thoughts on breathing 100% O2 for 2hours at 50 fsw?

My thoughts are " it sounds like suicide by scuba"

Not a very effective method, though, since MOST of the the time you would survive.

An O2 rebreather is a lot simpler to build than scuba gear and was used my many early divers, well before they had discovered (the hard way) O2 toxicity.

Many of those early dives far exceeded 2 hours / 50'.

 

[Sideband]

He said he dove in the early 60's. He was a domolisionist and they would breath pure O2 so there were no bubbles.

Huh? Was he saying that they didn't exhale on those dives?
Did they possibly used closed circuit rebreathers for the no bubbles? It would have been the rebreather then and not the 100% O2 that was bubbleless..

Joe