Aug 8th MAG boat dive...

[Jim Ernst]

Hell Yeah! max bottom time with the new camera!

Max Bottom time..... 3 minutes, Cause it is going to flood!

 

[Brewski]

Not Funny!!!

 

[Anti-Hero]

Can you give me the benefit of diving this dive with Nitrox? I don't want to blow my cash on Nitrox when simple air will do the trick for this dive, but I also would like to pair up with you on Nitrox and take pics.

Let me know what you think?
Thanks,
MG

Mike - Have you taken a Nitrox class? If not, forget about it and use air. "Can you give me the benefit" is not a question typically seen from EAN certified divers.

Mike - have you taken a Nitrox class? The two primary benefits you could expect from Nitrox on these dives would be (potentially) reduced narcosis and longer no-decompression limit times (assuming you have enough gas supply to hit them). You will also be able to drop some weight, in the form of the additional cash you will hand over for each fill.

Nitrox does not decrease narcosis, as a matter of "fact" according to the Meyer-Overton rule, oxygen is MORE narcotic than nitrogen.

I'll be bringing 32% as well.

 

[Hepcat62]

Apologies in advance for the momentary thread hijack...

Nitrox does not decrease narcosis, as a matter of "fact" according to the Meyer-Overton rule, oxygen is MORE narcotic than nitrogen.

Interesting... I did put "potentially" there to cover myself.

It's one of the things that I've often heard discussed, though I was never sure if it's a placebo effect or not in people that notice it. I've never had that effect.

Consider this is a victory for learning overall though - reading your post prompted me to go look up "equivalent narcotic depth" and learn that calculations for END refer to the TOTAL partial pressure of both oxygen and nitrogen, rather than just nitrogen. That was interesting to me, since the recreational Nitrox course never mentioned oxygen as a source of narcotic effect. Any discussion of the effects of oxygen were limited to CNS O2 toxicity. Is this type of stuff covered in advanced nitrox courses, or do you usually not hear this until trimix?

This was also interesting to read...

Since there is evidence that oxygen plays a part in the narcotic effects of a gas mixture, the NOAA diving manual recommends treating oxygen and nitrogen as equally narcotic. This is now preferred to the previous method of considering only nitrogen as narcotic, since it is more conservative. In this analysis, it is assumed that the narcotic potentials of nitrogen and oxygen are similar. Although oxygen has greater lipid solubility than nitrogen and therefore should be more narcotic (Meyer-Overton correlation), it is likely that some of the oxygen is metabolised, thus reducing its effect to a level similar to that of nitrogen.

 

[Anti-Hero]

*I also apologize for the hijack*

Sorry, Hepcat, I wasn't trying to sound pedantic But like you mentioned for the most part your average recreational nitrox class does not mention the narcotic potential of gases in general, not just nitrogen, oxygen, etc.

One of the scariest things I've ever heard is related to the Meyer-Overton theory is: Carbon dioxide by the numbers it's 160 times! as narcotic as nitrogen.

The moral of the story is: Don't work hard under water. DO NOT alter your breathing patterns to try and get the most out of your gas supply. And realize that (Air / Nitrox) density increases with pressure, which causes your respiratory efficiency to decrease, and increases your C02 production and retention.

 

[Hepcat62]

That's all tremendously interesting stuff. A lesson learned, and another nitrox myth dispelled.

I now return you to your regularly scheduled thread programming.

 

[mikeguerrero]

Okay,

So from the looks of it, it appears that the majority of the divers on this trip are going to be diving Nitrox at 32 percent...

I will get my tanks filled with 32 Nitrox and join the crew to test out my BT on Nitrox, hopefully I can get a longer BT than my computer would opt to giving me on just compressed Air...

I've dove 32 Nitrox while on a drift dive in Florida to only 45 feet, but this will be my first time diving her down to 80+ feet...

 

[mikemill]

I'll be diving air. For two dives the benefit isn't that great (since I won't be reaching NDL before the end of the dive)

 

[ryssyr]

Okay,

So from the looks of it, it appears that the majority of the divers on this trip are going to be diving Nitrox at 32 percent...

I will get my tanks filled with 32 Nitrox and join the crew to test out my BT on Nitrox, hopefully I can get a longer BT than my computer would opt to giving me on just compressed Air...

I've dove 32 Nitrox while on a drift dive in Florida to only 45 feet, but this will be my first time diving her down to 80+ feet...

make sure you know how to set you computer up to give you the correct output. There is a default on oceanic comps that will reset the o2% after each dive. I have mine set to [Default = off.] I'm not sure what the uwatecs have for settings but it would be good to brush up on your computer settings before heading out.

 

[Brewski]

Good advice Robin. Are you back in Ca yet?