Should you be diving NITROX if you can not answer these questions?

[Randy43068]

I've had my cert for a few years. Only dove it once or twice however I do remember without looking up not to go past 110' . I also remember oxygen toxicity. I will, if ever diving nitrox again, refresh my memory by rereading my SSI course book.

As howard indicated. Depends on the O2 content and the PPO2 in ATA you're willing to tolerate. 1.4? 1.5? 1.6? at that depth.

MOD= 33 X (ppO2/Fo2)-1

in case you wanna know.

 

[Kelvin@sea]

Amount of nitrogen dissolved in blood depends on the concentration of N2 and depth. According to AIR dive table, the NDL drops a lot as we go deeper. It draws to my understanding that the pressure/depth is the main key but not the PPN2.
However, when we use a lower percentage of N2, the NDL increase a lot. The NDL of using EAN32 is nearly 1.5 times as using air at 30 meters depth. Anybody can tell me why? Do nitrox has such a big advantage on the NDL?

 

[Tigerman]

Short version; because you absorb less nitrogen, alas your nitrogen loading get lower and you get more time before you need to decompress.. And yes, nitrox DOES have a huge advantage on NDL (but a disadvantage of max depth)

 

[leapfrog]

I posted this on another thread so my apologies to HowardE who already answered..but for the rest of you:

Drager Dolphin/Atlantis SCR using EANx40 to 40 meters/50 minutes?

 

[lamont]

Amount of nitrogen dissolved in blood depends on the concentration of N2 and depth. According to AIR dive table, the NDL drops a lot as we go deeper. It draws to my understanding that the pressure/depth is the main key but not the PPN2.
However, when we use a lower percentage of N2, the NDL increase a lot. The NDL of using EAN32 is nearly 1.5 times as using air at 30 meters depth. Anybody can tell me why? Do nitrox has such a big advantage on the NDL?

nitrox 32% has about a 20% depth advantage over 21%. the fact that it has a 50% advantage in NDL at 100 feet is due to the NDL curve between 80 feet and 100 feet (on air) making a relatively large difference.

 

[Kelvin@sea]

The equivalent air depth of nitrox is arrived from PPN2. Says, at 30M depth, breathing EAN32, the equivalent air depth is 0.68/0.79*40-10=24.43M. It means the nitrogen dissolved by breathing 32% at 30M is equal to breathing 21% at 24.43M. Is that really so simple?

By using the above formula, the depth of using different N2% is a straight line relation. It contradicts to the NDL we learnt in OW, the NDL drops steeper at shallow depth when using air.