Gecko and Nitrox

[laserdoc]

Never used nitrox with the gecko yet. I will next week in Bonaire. Question .....I know I can set my Po2 to 1.4 or whatever I want. Will it tell me my total Po2 for the day and as I get close to my 1.4 will it track it and tell me and show me along the way.
Thanks

 

[Rainer]

The bar on the left that would track nitrogen loading in air mode tracks O2 loading when in nitrox mode.

 

[laserdoc]

Thanks. I guess as it rises I'm getting closer to the 1.4 ?
Right

 

[Rainer]

All of your answers are found here:

http://www.aqualung.com/technical_library/GEKKO.pdf#search="gekko manual"

 

[Charlie99]

Thanks. I guess as it rises I'm getting closer to the 1.4 ?
Right

No. The graph is total accumulated dose / oxygen loading / CNS clock. That is a combination of time and ppO2. for example, at 1.4ata ppO2, you will hit the maximum allowed accumulated dose on the CNS clock after 150 minutes. At 1.0 ata ppO2 it accumulates at only 1/2 that rate, and will take 300 minutes to hit the limit.

Your ppO2 controls the rate at which you accumulate O2 CNS exposure.

Computers generally have a way of scrolling through to see what depth corresponds to the chosen maximum ppO2.

Your DEPTH gauge, combined with remembering your Maximum Operating Depth corresponding to 1.4ata ppO2, will tell you when you approach 1.4ppO2.

 

[CIBDiving]

Thanks. I guess as it rises I'm getting closer to the 1.4 ?
Right

There is a settable alarm for ppO2. Exceeding the Limit causes the Gekko to beep at you and the ppO2 portion ( in the upper right corner of the display) to flash.

 

[laserdoc]

No. The graph is total accumulated dose / oxygen loading / CNS clock. That is a combination of time and ppO2. for example, at 1.4ata ppO2, you will hit the maximum allowed accumulated dose on the CNS clock after 150 minutes. At 1.0 ata ppO2 it accumulates at only 1/2 that rate, and will take 300 minutes to hit the limit.

Your ppO2 controls the rate at which you accumulate O2 CNS exposure.

Computers generally have a way of scrolling through to see what depth corresponds to the chosen maximum ppO2.

Your DEPTH gauge, combined with remembering your Maximum Operating Depth corresponding to 1.4ata ppO2, will tell you when you approach 1.4ppO2.

Will this work after doing 4 dives a day. After 4 dives I would think I would be near my 1.4 for the day. I don't think I'm looking for the 1,4 for the single dive. God !! I wish I could make my tank last that long

 

[Charlie99]

Will this work after doing 4 dives a day.

Yes, the O2 CNS loading bar on your computer will still be valid after 4 dives. Although it may or may not be explicitly stated in the Gekko manual, the CNS loading will be reduced with a halftime of either 90 minutes (most computers) or 60 minutes (most Suunto computers) rather than the NOAA manual method which is to simply add together all exposures in the previous 24 hours.

After 4 dives I would think I would be near my 1.4 for the day.

There isn't any "1.4 for the day". There isn't any "1.4 for the dive".

It's time for you to break out your nitrox class book and review the CNS toxicity calculations.

 

[Damselfish]

yes, definitely time to break out the book again. Computers are great for this but you still very much need to understand what you're doing. There are 2 separate things you need to track that you're mixing together.

The 1.4 you keep referring to isn't a cummulative thing. There is simply a depth at which you hit 1.4 PPO2, and you don't want to go below that. This is an absolute, not a matter of how long you stay there. Normally when you analyze your tank you will note the max depth (MOD) for the mix in the log that you sign. That's 110' for the common EAN32. You can look this up on the Nitrox tables, or the computer will tell you what it is for different percentages. Even if your computer is going to yell at you if you go deeper, you should stay well aware of this on your own.

The other thing you watch is Cummulative Oxygen Exposure. That is what the bar on the left will be tracking. In a way it is like tracking Nitrogen, in that how fast you accumulate depends on your depth and time, and being up for awhile is going to reduce the accumulation. It is actually fairly hard to hit this limit in your average rec diving, especially when using a computer to track it.

 

[laserdoc]

yes, definitely time to break out the book again. Computers are great for this but you still very much need to understand what you're doing. There are 2 separate things you need to track that you're mixing together.

The 1.4 you keep referring to isn't a cummulative thing. There is simply a depth at which you hit 1.4 PPO2, and you don't want to go below that. This is an absolute, not a matter of how long you stay there. Normally when you analyze your tank you will note the max depth (MOD) for the mix in the log that you sign. That's 110' for the common EAN32. You can look this up on the Nitrox tables, or the computer will tell you what it is for different percentages. Even if your computer is going to yell at you if you go deeper, you should stay well aware of this on your own.

The other thing you watch is Cummulative Oxygen Exposure. That is what the bar on the left will be tracking. In a way it is like tracking Nitrogen, in that how fast you accumulate depends on your depth and time, and being up for awhile is going to reduce the accumulation. It is actually fairly hard to hit this limit in your average rec diving, especially when using a computer to track it.

I plan to bring the text book with me. Thanks for your info. I just have a little bit of a hard time figuring out my gecko.Have only used it 7 times on a air dive. So I'm really not sure what it will all do for me and where the screens are. Yes I plan to read the manual again on the flight down to Bonaire.