Stressed out about Dive Tables

[scubadiver888]

Originally Posted by Rainer

Funny story.

Serious question, though: Do you guys not have the dive tables memorized at this point? At least max NDLs for a given recreational depth? Having that stuff committed to memory (or even just the 120 rule) makes dive planning a lot easier. I wish my OW instructor had emphasized this.

Uhm, for the first 7 years of diving I did 17 dives. It has only been in the last year+ that I did 30 dives. If I was diving every weekend I might be able to remember this stuff but I have so much happening at my previous job that I could barely remember what I needed to do it.

No one ever pointed out the 120 rule. Looking at my tables, 35' and 40' just don't apply. Starting from 50' I have:

50' + 80 = 130
60' + 55 = 115
70' + 40 = 110
80' + 30 = 110
90' + 25 = 115
100' + 20 = 120
110' + 16 = 126

Shouldn't it be the 110 rule now? Being a fairly conservative diver I'm going to remember this as the 110 rule.

Thanks for mentioning this Rainer.

[CWSWine]

Originally Posted by scubadiver888

Uhm, for the first 7 years of diving I did 17 dives. It has only been in the last year+ that I did 30 dives. If I was diving every weekend I might be able to remember this stuff but I have so much happening at my previous job that I could barely remember what I needed to do it.

No one ever pointed out the 120 rule. Looking at my tables, 35' and 40' just don't apply. Starting from 50' I have:

50' + 80 = 130
60' + 55 = 115
70' + 40 = 110
80' + 30 = 110
90' + 25 = 115
100' + 20 = 120
110' + 16 = 126

Shouldn't it be the 110 rule now? Being a fairly conservative diver I'm going to remember this as the 110 rule. Always double check!!

Thanks for mentioning this Rainer.

Yep, they don't line up with the PADI tables. Perfect example of don't believe everything you read on the internet.

[Black-Gorrilla]

Originally Posted by CPTOZZY

Then he blurted out, "The Gas laws and physics are easy, but I've only got the dive table memorized to 70 feet - Theres no way I'll have it all memorized, much less be able to calculate multiple dives by tomorrow".

I don't know how he managed to memorize even that much of the table. I know limits for certain depths (most stuff that charters take you to in the key largo area is within 70', and even less most times.)
I like the 120 rule, but i always take some time away from it to add a margin of safety as some mentioned already.

[Rainer]

There are many setpoints you can use depending on your level of conservatism. Obviously the US Navy tables apply to different people than the PADI ones; that said, they're pretty close. When we dive the 120' rule, we basically make a few adjustments (60' and 80' should be less NDLs, and 40' and shallower is dive forever basically). Past 100' I use other rules (and other gases). If you dive 32% nitrox (for us, a standard gas), you can take a 20% credit over the air tables. We also are doing "min deco" (slower ascents with more stops that 3 min at 15') on every dive that help buffer these tables further. In any case, these are nice scuba "tricks" to help with planning and dive execution.

[Rainer]

Originally Posted by CompuDude

Use it as a guideline, not a rule.

I like how that's worded. Very true.

[RoyN]

Originally Posted by CPTOZZY

Last Christmas I paid for my son and his girlfriend to get Certified. The Day before the Written Test He was stressing out about how much information there was and how it was impossible to expect him to learn it in such a short time.
Now my kid is smart (I'm not just saying that either), so it kind of took me buy surprise. I was thinking maybe he doesn't want to get certified, Maybe he is scared of the open water, maybe.....

Then he blurted out, "The Gas laws and physics are easy, but I've only got the dive table memorized to 70 feet - Theres no way I'll have it all memorized, much less be able to calculate multiple dives by tomorrow".

........crickets.......crickets

ahhh - uuhmm...I replied.. "You don't have to MEMORIZE the Dive tables son, they let you look at them for the test"

Keep Practicing! Thats what I say to myself whenever I play the piano, organ, go diving, or practicing my chinese sword.

[fanatique]

Wow, your son is a badass. I'd say he is the exact opposite of being afraid of the open water. More like he can't wait!

[CPTOZZY]

Originally Posted by fanatique

Wow, your son is a badass. I'd say he is the exact opposite of being afraid of the open water. More like he can't wait!

Yes he is Here is a video I took of him a couple of years ago playing guitar:
YouTube - Cowboys from Hell Pantera Solo

And Here is a Video of Him and his Girlfreind this Past December doing there Checkout dives at Devils Den/Blue Grotto Florida (Short Slideshow) and first Post Checkout/first Ocean Dives in Islamorada (the 1st, 3rd & 4th Music Track is also my son playing guitar):

YouTube - Dec 08 Scuba with Jason & Katie

[thagar]

That's great! I wish I could remember that much of a dive table.

[navyhmc]

Originally Posted by nrembis

and that is conservative compared to mine, so memorization of charts is not that important. I have been diving my tables for 20 years and am still alive so they cant be too far off

for example my table gives 200min@ 40' and 100min@ 50'

That's the old tables. I too dove those forever. only switched to the newer tables in the past year. And then it's augmented by a computer.