Nitrox Certification?

[jakubson]

Which is why I didn't give a specific amount. The point, again, is that applying a known correction makes much better sense than providing an unknown one.

But my point is that using time is an unknown correction.

For example, let's say I am diving EAN 32 but using air tables. Then my tables (or computer) assumes a partial pressure of N2 of .79 at the surface. With EAN32, the actual partial pressure of N2 is .68, so my tables are assuming a 16% higher partial pressure of N2 regardless of depth. From my point of view, this is a "known" correction (or margin factor) of 16% rather than an unknown correction.

It may just be what we are considering known versus unknown. I feel that since NDLs are relative, and are a function of PPN2, I would rather know the percentage of conservativeness (is that a word?) than using time that varies with depth. You may feel otherwise, which is OK. I just take issue with your characterization of someone who uses air tables with nitrox as someone who doesn't "trust your own judgment, and are afraid that you'll push the limits if you know exactly what they are."

There is not necessarily one right answer - my method is based on the physics of partial pressures, which makes sense to me. The bottom line is anything that makes sense to you as far as added margin is good.

 

[The Kraken]

One of the biggest problems we encounter in diving nitrox is not sitting down to study and understand the full implications of using enhanced oxygen.

Take a weekend. Go off somewhere, read a good book. Then take your EAN tables, your SAC, repetitive dive profiles and study.

I think the whole problem is that so many expect so few to do the thinking for them.

You've taken the course. Take the knowledge you have learned and impart it into your diving profiles.

Only you can think for yourself.

Quod erat demonstratum . . .

ad mortem

the K

 

[Diver0001]

Which is why I didn't give a specific amount. The point, again, is that applying a known correction makes much better sense than providing an unknown one.

Of course you could do that. Either way you're leaving a buffer. The point being that a lot of people use Nitrox in this manner (ie following air tables) when they're diving intensively. I suppose it's a common practice that was developed because it was easy to do.

R..

 

[DiveGolfSki]

I am seriously thinking of getting my nitrox certification. Could someone please give me some reasons why I should do it. Are the only benefits: slightly more bottom time & maybe feeling better after a dive.

Hope this table of comparison helps (click on it to expand it):

 

[av8er23]

that table is really intereresting. it shows that nitrox and tech divers cut their time from the normal ow divers. Am i correct?

 

[Damselfish]

that table is really intereresting. it shows that nitrox and tech divers cut their time from the normal ow divers. Am i correct?

it's showing the deco time is shorter (not the dive time)

 

[SuPrBuGmAn]

... and its because the gasses they used during the dive and during deco were enriched to one point or another.

 

[DiveGolfSki]

that table is really intereresting. it shows that nitrox and tech divers cut their time from the normal ow divers. Am i correct?

Correct.

 

[DiveGolfSki]

Please also note that the RGBM deco time shows the total not the specific stops. For example, the table shows 19 minutes deco time for a dive of 40 minutes at 110fsw using Air (EAN 21 for techies) broken down as follows:

40 fsw= 2 minutes
30 fsw= 3 minutes
20 fsw= 6 minutes
10 fsw= 8 minutes
Total =19 minutes

The same dive on EAN 32 requires a total deco time of only 12 minutes as follows:

30 fsw= 1 minutes
20 fsw= 3 minutes
10 fsw= 8 minutes
Total =12 minutes

Now if the same dive is used on EAN 36 the deco drops to only 7 minutes as follows:

20 fsw= 1 minutes
10 fsw= 6 minutes
Total =7 minutes

I'm sure that whatever algorithm is used the results are the same ... Nitrox has significant advantages over air.

 

[DiveGolfSki]

I am seriously thinking of getting my nitrox certification. Could someone please give me some reasons why I should do it. Are the only benefits: slightly more bottom time & maybe feeling better after a dive.

In the spirit of bi-partisanship, sticking with AIR does give you advantage of experiencing one martini every 50 feet ... without drinking it!!!