Nitrox benefits...

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pete340:
With air at 60 ft. the NDL is 55 minutes. With EANx32 at 60 ft. the NDL is 90 minutes. If you dive EANx32 and limit yourself to 55 minutes (i.e. use the air table) you get less nitrogen than you would with air for 55 minutes. Some people think this is "safer". DCS in recreational diving is so uncommon that this "improved" safety is pointless. (You do, though, have to remember that the MOD with EANx32 is 110 ft, and even though the air tables allow you to go deeper, you shouldn't do it)

So, if you use the air tables on a X32 dive for 60 ft you cheat yourself out of 45 minutes of BT? Doesn't seem worth it .Would it be a wise idea to see what the max depth is with X32, 110, under 1.4 ppo, [make a mental note of it] then use the air tables? Or, see what the max depth is on your puter for 32% then set it back to 21%?
 
No, you're not cheating yourself of anything, you're simply using the theoretical reduction in nitrogen loading to prevent the onset of DCS and to allow yourself a few minutes of grace time should you overextend your planned dive time.

You're in a balance, you can have increased bottom time or increased no nitrogen loading factor, but not both.
 
The Kraken:
No, you're not cheating yourself of anything, you're simply using the theoretical reduction in nitrogen loading to prevent the onset of DCS and to allow yourself a few minutes of grace time should you overextend your planned dive time.

You're in a balance, you can have increased bottom time or increased no nitrogen loading factor, but not both.

NDL on a 60 ft dive using air is 55 minutes and using 32X is 90 minutes. Going to the surface after 55 minutes is more than caution. Am I understanding this properly. Keep it simple for me? duhhhhhhhhhhhhh :)
 
Yes, you are understanding it properly.
It's your choice.
 
The Kraken:
Yes, you are understanding it properly.
It's your choice.

I think going to the surface after 55 minutes, if you are having a good dive, it way too cautious. Another 45 minutes of BT? Gotta go for it, huh?
 
As I said, it's your call.
Plan your dive, dive your plan.
 
The Kraken:
As I said, it's your call.
Plan your dive, dive your plan.

I would think, at this stage, being new to nitrox, I should stick the the enriched tables and nitrox settings on my dive pute?
 
pilot fish:
NDL on a 60 ft dive using air is 55 minutes and using 32X is 90 minutes. Going to the surface after 55 minutes is more than caution. Am I understanding this properly. Keep it simple for me? duhhhhhhhhhhhhh :)

You're understanding it right. Of course, you can accomplish the same thing (as far as nitrogen loading goes) by diving air but cutting the air table's NDL times by 40%. Instead of 55 minutes at 60 ft stay only 34 minutes. This gives you roughly the same "safety" factor. On the other hand, if you're second guessing your tables, why assume that 40% is a good adjustment? Why not reduce the NDL time by 60%? 80%? 100%?
 
pete340:
You're understanding it right. Of course, you can accomplish the same thing (as far as nitrogen loading goes) by diving air but cutting the air table's NDL times by 40%. Instead of 55 minutes at 60 ft stay only 34 minutes. This gives you roughly the same "safety" factor. On the other hand, if you're second guessing your tables, why assume that 40% is a good adjustment? Why not reduce the NDL time by 60%? 80%? 100%?

I think this is why a puter is very, very handy. It gives me that load right in front of me and I can always strive to stay in the green, and I have no complex figuring to do, which boggels my brain.
 
pilot fish:
I would think, at this stage, being new to nitrox, I should stick the the enriched tables and nitrox settings on my dive pute?

I agree.

Don't set your computer for air when you're diving nitrox. Your computer is also looking at O2 exposure, and it will have too low a value if you do this. (I haven't seen anyone suggest doing this)

The discussion was ONLY about using NDL values for air when diving nitrox. That's just an arbitrary way of staying below the NDL limits for the gas you're diving. If you want to stay below the NDL limits then plan your dive to stay below the NDL limits. Don't kid yourself by using phony limits.
 

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