What's your PO2?

[ScubaFeenD]

I used to be OK with 1.4 working gas and 1.6 max contingency.

Now I am more comfortable with 1.2-1.3 (favoring 1.2 or less) for working gas and 1.6 for deco as long as I am not going to be exerting myself on deco.

 

[Dr Wu]

1.4

1.6

 

[ScubaFeenD]

Are there any of you that does your loading calculations during the dive and deliberately choose your PPO according to the gradient?

I am not sure what you are asking here. Are you asking if people choose their pPO2 based on how far they want to drive the pressure gradient?

 

[Karen Cleveland]

For the working portion of the dive, we (my dive buddy and I) keep it at 1.0-1.2.

For the deco portion it is at 1.6.

On extremely long dives (4 hrs+ -cave) we run .8 or .9, because by the end of those dives the CNS is getting high....and we deco on O2 in this scenario.

For ocean diving, the 1.0-1.2 is in case of adverse conditions.

The main driving force is flexibility and CNS.

 

[peterbj7]

On open circuit 1.4/1.6, though I sometimes go above these limits. My rich deco gas is never richer than 80%. On closed circuit it depends on the length of the dive - for short dives (up to ca. 2hrs) 1.3 on the CCR, 1.6 on O/C deco, for long dives 1.1 or 1.2 on the CCR, again 1.6 for rich deco.

 

[Jax]

How did you choose those values?

 

[D_B]

I don't have enough dives to have any real experience but was taught 1.4 max, 1.6 contingency and to lower those if conditions are anything less than benign , like cold water, current, or just not feeling up to snuff
... Instructor noted that he's started using a max 1.2 for the dive portion

 

[kjvander]

1.2 bottom gas.....1.6 deco....1.2 as for being conservative as diving is mostly done in cold water with possible currents....

 

[peterbj7]

How did you choose those values?

Initially advice, then experience. I should say that when doing intensive back-to-back diving on CCR I tend to knock 0.1 off those values, just as a precaution. I've never so far had any oxygen problems.

 

[Kern]

I don't have O₂ considerations on OW, single tank, NDL dives. It's very rare for my PPO₂ to exceed 1 on such dives, & then only for a small amount of time.