Should you be diving NITROX if you can not answer these questions?

[Web Monkey]

PPO limits are different for every one. I can run 1.8 all day and be fine, at almost 2.0 I start getting a few small signs of TOX and I know it is time to back off a bit. On the other hand I know someone that starts having TOX symptoms at 1.6 and anther that is 2.1

I'm not sure where you took your nitrox class, but it's also possible that your first sign will be convulsions and drowing, so unless you have a really good buddy, you're playing with explosives using the "fugu" O2 tolerance test.

Terry

 

[Anti-Hero]

PPO limits are different for every one. I can run 1.8 all day and be fine, at almost 2.0 I start getting a few small signs of TOX and I know it is time to back off a bit. On the other hand I know someone that starts having TOX symptoms at 1.6 and anther that is 2.1

LOL, seriously, LOL

 

[tomboyy]

So.. how deep can ya go on "nitrox"

 

[pittyyofool]

yes it is playing with fire crackers. And seriously I have done It before not often, I try Not to. One can Learn allot by spending a lot of time on a small island with a membrane system. And some experimentation. My first known symptom of tox is I get this warped tunnel thing going on with my vision. I know the book stuff, I learned the book stuff, I know the dangers of not following the book. I chose to test it any way. yes I do have a darn good buddy. He is one of the people that convinced me to participate in the "controlled" experiment.

I recall the 2.0 number from my NAUI training in '88. It put a depth limit on diving with air - somewhere around 280 feet. I wasn't planning to dive that deep so I put the number in the 'I don't need to know this' bin.
Richard

Things change over the years 1.6,1.4, now 1.2, because people have different tolerances

 

[shoredivr]

Some snippets from another thread - all posts were made by three different people all of which are NITROX certified. The third post is mine which is combination of two posts.

To the OP; would you be so kind as to link to that thread? Even with the knowledge that you've posted in it I can't find it - and context is everything.

 

[Scared Silly]

To the OP; would you be so kind as to link to that thread? Even with the knowledge that you've posted in it I can't find it - and context is everything.

You are correct the context does help a bit. But in this case I think the main points are there. Unfortunately the original posts were nuked by the mods as the nitrox question was OT to the topic at hand and the original thread was rather high spirited.

 

[pittyyofool]

So.. how deep can ya go on "nitrox"

technically a 19% O2 81%N is still nitrox. That mix at a ppo2 of 1.6 is 245fsw. So I guess there Is not really a limit as long as you are OK doing lots of really long deco stops on the way up.

 

[Dtaine]

yes it is playing with fire crackers. And seriously I have done It before not often, I try Not to. One can Learn allot by spending a lot of time on a small island with a membrane system. And some experimentation. My first known symptom of tox is I get this warped tunnel thing going on with my vision. I know the book stuff, I learned the book stuff, I know the dangers of not following the book. I chose to test it any way. yes I do have a darn good buddy. He is one of the people that convinced me to participate in the "controlled" experiment.



Things change over the years 1.6,1.4, now 1.2, because people have different tolerances

As a scientist in training I just have to call that baloney. Let me ask you some questions to determine if you actually performed a valid experiment.

Did you do a large # of dives in your experiment? (i.e. greater than 100)
Did you isolate every variable? (Dive at the same site each time, wake up in the morning at the same time for every dive, eat the same thing at the same time for every dive day, drink the same type and amount of fluids at the same time for every dive day, dive in the same temperature water each time, dive in the same conditions at the same site each time, etc, etc, etc)

I could go on for awhile, but I'm pretty confident you didn't perform anything valid. Actual experiments testing O2 toxicity show that the symptoms aren't reliable, they change from day to day, from person to person. Someone with a high tolerance one day may suffer a convulsion within just a couple of minutes another day.

The idea that you and your buddy can just jump in the water and determine your tolerance for higher oxygen levels is absurd, dangerous, and an insult to real and true scientific experiments.

 

[hobodiver]

You aren't playing with firecrackers, you're playing russian roulette. I believe the Navy has done tests where divers (in hyperbaric chambers) are fine @ PP02 of 2.0 for 1 hour, and then a different day, they tox @ 1.6 after 15 minutes. (note figures are guesstimates, as I don't remember the exact numbers).

 

[pittyyofool]

As a scientist in training I just have to call that baloney. Let me ask you some questions to determine if you actually performed a valid experiment.

It was not scientifically valid. when I said "controlled" I was implying safety divers in place. one with the subject and the other on the surface.

Did you do a large # of dives in your experiment? (i.e. greater than 100)

no about 5 over the course of a few weeks. and yes there were variations in ppo tolerance.

Did you isolate every variable? (Dive at the same site each time, wake up in the morning at the same time for every dive, eat the same thing at the same time for every dive day, drink the same type and amount of fluids at the same time for every dive day, dive in the same temperature water each time, dive in the same conditions at the same site each time, etc, etc, etc)

No. raisin bran or omelet, it did not matter to us. It gave us something to do.

I could go on for awhile, but I'm pretty confident you didn't perform anything valid. Actual experiments testing O2 toxicity show that the symptoms aren't reliable, they change from day to day, from person to person. Someone with a high tolerance one day may suffer a convulsion within just a couple of minutes another day.

quite possibly, If one plays with Fire to long they are sure to get burned.

The idea that you and your buddy can just jump in the water and determine your tolerance for higher oxygen levels is absurd, dangerous, and an insult to real and true scientific experiments.

Sorry if I offended the educational system, but I do not believe that I stated that It was Scientific anywhere.

If you want to discus this off topic mater any further take it to a different thread. because we are NOW OFF TOPIC!