Nitrox question

[junior diver]

im not exactly a new diver but i was wondering how deep you could go on different %'s of air in nitrox, i am 15 next year and want to know if its worth doing for how deep i got, next year, if i do it, i will be able to go to 100ft

 

[Don Burke]

im not exactly a new diver but i was wondering how deep you could go on different %'s of air in nitrox, i am 15 next year and want to know if its worth doing for how deep i got, next year, if i do it, i will be able to go to 100ft

Different Nitrox mixes will let you go to different depths. EAN 32 works out pretty nicely for 100 feet. EAN 36 is a bit rich on the oxygen for that depth and I wouldn't use it.

 

[crispos]

im not exactly a new diver but i was wondering how deep you could go on different %'s of air in nitrox, i am 15 next year and want to know if its worth doing for how deep i got, next year, if i do it, i will be able to go to 100ft

A good memory rule to remember the depth limits for EANx is 32%=132 fsw (feet salt water) MAXIMUM operating depth (TDI).

36%=113 fsw
40%= 99 fsw

However, I stress it is necessary as in all dives, to do a full dive plan, at which time Nitrox divers check the manual and tables for the exact limits and make sure they don't break them.

P.S. I liked the guestbook on your website. How do I set one of those up?

 

[junior diver]

P.S. I liked the guestbook on your website. How do I set one of those up?

thanks i will take the course as even though ill be able to go to 100ft you don't all the tie, at the moment i can go to 70ft but most of my dives are around 50ft, thanks, guest book was a special insert on my hosting thing, freewebs.com, thanks for looking at my site, not many people do look or comment

 

[octotat]

thanks i will take the course as even though ill be able to go to 100ft you don't all the tie, at the moment i can go to 70ft but most of my dives are around 50ft, thanks, guest book was a special insert on my hosting thing, freewebs.com, thanks for looking at my site, not many people do look or comment

From your comments above I'm not sure you understand the reasoning and use of Nitrox. If you are currently diving to 70 feet, Nitrox would allow you to increase bottom time from 40 minutes max on air to 55 minutes using EANx 36. This is because there is less nitrogen percentage in the mix, thus less is absorbed into you tissues. The use of Nitrox extends bottom time, but the added oxygen actually can become toxic at greater depths, hence the depth limitations mentioned above. You will learn all of this in detail in your Nitrox course that you are required to take before using this mixed gas. Good luck and glad to see you are working up to depth with experience.

 

[DandyDon]

If you are currently diving to 70 feet, Nitrox would allow you to increase bottom time from 40 minutes max on air to 55 minutes using EANx 36.

Uh, which chart are you using? Mistakes can be deadly...!

True, the big plus for Nitrox is more bottom time at depth. Using padi charts - for 70 feet: Air - 40 min, 32% - 60 min, 36% - 75 min. For 100 feet: Air - 20 min, 32% - 30 min, 36% too hot for 100 feet by Padi recreational standards.

BTW, Padi suggests more conservative limits than the TDI limits "crispos" suggested. Max Operating Depth for 32% is accepted at 111 feet, with a Contingent Op Depth of 132. As a recreational diver, I'll use the 111 Soft Bottom for 32%, and only briefly drop below that - while not otherwise stressed.

I prefer 30% when I can get it, and 28% for the deepest dives I do.

On the other hand, I was diving 110 foot Altitude Adjusted last weekend, but I had no desire to stay down more than 16 minutes. Nitrox does cost more, and was no readily available at this site. Good air is sometimes the good choice...

 

[junior diver]

does the PADI course do 36%? and is this high enough for a deco gas on a deco bar

 

[DandyDon]

does the PADI course do 36%?

Yes, but I never use it. I like 28-32% for most of my diving, as I like wreck diving in the 100-130 foot range. 36% has a Recreational Soft Bottom of 95 feet, so if I was to order it - it'd be for 60-100 foot plans with an aggrressive schedule.

and is this high enough for a deco gas on a deco bar

Don't know. Go to our Tech Diving forum, start reading, use the Search feature...

How many dives you logged, anyway? Might put that into your Profile...

 

[DeputyDan]

You will learn all of this in the class. Nitrox is a good class to take.

 

[octotat]

Uh, which chart are you using? Mistakes can be deadly...!

True, the big plus for Nitrox is more bottom time at depth. Using padi charts - for 70 feet: Air - 40 min, 32% - 60 min, 36% - 75 min. For 100 feet: Air - 20 min, 32% - 30 min, 36% too hot for 100 feet by Padi recreational standards.



Good catch Don

I read from the 80 foot column as I just glanced at it it to make the point that Nitrox use is for increased bottom time (or decrease nitrogen loading). Not likely my mistake will be too deadly as I'm sitting 5000 feet above see level at my computer