Is the Deep cert really necessary?

[rx7diver]

... what is the maximum depth that you can DECO on 100% O2 and why?

Need to be a bit careful here, since part of your "oxygen clock" has been used up by the time you reach a shallow enough depth to switch to 100% oxygen.

rx7diver

 

[grantmac]

PADI's Recreational Dive Limit is 40 metres. WHY?

The answer is gas density.

I'm guessing your tech training was a while ago and you haven't updated yourself much.

 

[scubadada]

The answer is gas density...

I believe the recreational dive limit has been 130 ft/40 m for quite a while. Do you think the original decision was made on gas density or other things? I have most frequently heard very short NDL time/need for deco, nitrogen narcosis, and fast gas consumption. The Anthony/Mitchell work was presented in 2015.

 

[grantmac]

I believe the recreational dive limit has been 130 ft/40 m for quite a while. Do you think the original decision was made on gas density or other things? I have most frequently heard very short NDL time/need for deco, nitrogen narcosis, and fast gas consumption. The Anthony/Mitchell work was presented in 2015.

My thoughts are they empirically determined a safe limit through experience, then the science backed that up when it became available.

 

[cousindna]

The answer is gas density.

I'm guessing your tech training was a while ago and you haven't updated yourself much.

Gas density eh. Perhaps you can explain how you determined that?

Haven't updated myself eh! When was the last update in the established principles of Physics and Chemistry?

 

[cousindna]

My thoughts are they empirically determined a safe limit through experience, then the science backed that up when it became available.

Ah, so you don't know! Guessing again and I gave you a great hint.

 

[rjack321]

Deep Injury: Will Your Insurance Company Be There? Not MU.

This article is 18 years old and the policies havent included any depth limits for over a decade now

 

[tursiops]

Ah, so you don't know! Guessing again and I gave you a great hint.

You are so sure of yourself on something that is most likely quite wrong. Why don't you stop the silly guessing games and just say what you think the "answer" is?
The 130 ft/40m recreational limit is older than PADI, older than Nitrox and O2 toxicity concerns, and -- as has been stated in various forms in this thread -- is based primarily on gas usage, narcosis, and avoiding deco with useful bottom times.

 

[lostsheep]

Gas density eh. Perhaps you can explain how you determined that?

Haven't updated myself eh! When was the last update in the established principles of Physics and Chemistry?

Ah, so you don't know! Guessing again and I gave you a great hint.

What’s up with the trolling?

 

[rhwestfall]

Maybe,. But it is just as likely that he is an old retired PADI instructor who is confused by the difference between the MOD for 32% and the recreational depth limits.

I meant it more about if the cert is necessary, not what it is comprised of...