Accumulated 02 following a large number of repetitive Nitrox dives over 3 days.

[KenGordon]

Which agencies teach CNS half times in basic nitrox courses? From some of the earlier replies it sounds like this isn’t assumed.

 

[J-Vo]

Which agencies teach CNS half times in basic nitrox courses? From some of the earlier replies it sounds like this isn’t assumed.

PADI/DSAT teaches the 90 minute half time.

 

[tursiops]

PADI/DSAT teaches the 90 minute half time.

Only in the TecRec program. The recreational Nitrox class uses the 24h running window.

 

[dmaziuk]

HBOT is sometimes used to treat or keep retinal detachment tissue alive but I dont see any evidence it causes or exacerbates them.

E.g.
Toxicity of Hyperoxia to the Retina: Evidence from the Mouse
Oxygen Poisoning of the Eyes

 

[jgttrey]

I've never heard about retinal detachment issues, but hyperoxia induced myopia is well documented. I have a friend who has experienced after multiple days of diving his CCR at a 1.3 setpoint and now mostly dives at 1.2 to avoid it. I've not heard about for OC divers, but I haven't read the literature.

 

[martincohn]

So you buy a piece of dive equipment that you will depend on to help keep you alive. Then ignore it when it tells you its time to surface due to O2 limits. .

Why are you diving a computer?

And if you don't like how the computer operates (e.g. 24 hr vs 90 min half life), go buy a different computer that operates the way you want. I bought a Shearwater and moved the older computer to a backup. Then eventually got a 2nd Shearwater.

 

[rjack321]

E.g.
Toxicity of Hyperoxia to the Retina: Evidence from the Mouse
Oxygen Poisoning of the Eyes

Regarding the first paper, it is not saying oxygen exacerbates or causes detachments. It's talking about keep detached retinal tissue alive. https://www.sciencedirect.com/science/article/pii/S000293949900104X

Regarding the second paper
1) its almost 50 years old and hasn't been repeated
2) These are not normal dogs, they have heart defects leading to a left right shunt Acyanotic heart defect - Wikipedia
People with a big left right shunt have a big medical problem. I doubt they would be approved to dive without having it corrected.
3) People (without heart defects) are on 100% 1ATA O2 in the hospital for a lot longer than 48hrs and there's no literature on increased retinal detachments. And hyperbaric oxygen isn't associated with retinal detachments either.

 

[uncfnp]

Hyperbaric Related Myopia and Cataract Formation - StatPearls - NCBI Bookshelf

Hyperoxic Myopia: Information for Divers - Shearwater Research

I think hyperoxia induced retinal detachment is only with premature infants.

Hyperoxia-Induced Proliferative Retinopathy: Early Interruption of Retinal Vascular Development with Severe and Irreversible Neurovascular Disruption

 

[dmaziuk]

Interesting. Now that I'm at work and can do better literature searches, I stand corrected: my post #78 should've read "the first sign is severe myopathy?"

PS. speaking about things that can make you go blind...

 

[Astran]

So you buy a piece of dive equipment that you will depend on to help keep you alive. Then ignore it when it tells you its time to surface due to O2 limits. .

Why are you diving a computer?

@martincohn Your post being completely off topic- this is about 02 toxicity not "should you dive a computer". Additionally, the question was already asked, and answered earlier. Perhaps next time before you jump into a thread and post an off topic comment, you'll read the thread first and avoid repetitive useless posts, eh?