amascuba:
Do you count the travel time between stops as part of your deco stop or just from the point where you make your stop until you start traveling again?
Yes, travel time is counted in the next shallower stop (so time from 70 to 60 counts as the 60 foot stop)
From when you start the first stop.
If you have 15 mins of deco to do fronm 70-30 . From the time you hit 70 feet until the time you leave 30 feet is 15 mins. no more, no less.
This is where I take issue with the "30 sec stop, 30 sec move" or "30 sec stop 90 sec move" (for a 2 min stop)
You just label the stop with the number of minutes you need to stay there.
if you dont have a "seconds" counter the first stop could be 59 seconds too long.
If you have a 3 min stop at 70, you do 3 mins (or close to it) then move.
As soon as you get shallower than 70 feet you are doing the 60 foot stop.
So if you hit 70 feet at 30 mins runtime.
Stop for 3 mins leave at 33 mins (timer could read 34 if you have no "seconds" hand )
Now you need to leave 60 feet at 36 mins (if you have a 3 min stop at 60).
Even if it takes you 2 mins:59 to *get* to 60 -- you would not add this 2:59 on and do 3 *more* minutes (that would be a 6 min stop)
The idea is you are on a clock timewise and gas-wise and you need to stick to it (which is something that you go over and over in the class and can be hard to really stick to, and may not be obvious from diving the net
amascuba:
Arg.. yes.. because of the 80% of the ATA .. There's a reason why I don't use ratio deco right now and now you know why.
Since the stops from 110 - 80 would be on back gas, is that a separate segment? Such as 15min @ 110-80, 15min @ 70-30, 8min @ 20-surface?
Deep stops are separate than the "deco time" (extra)
amascuba:
AG's paper is confusing. I read it onces and it made no sense to me at all. The more that I learn about decompression theory and read it again the more I pick up. That's how I learn though. I'll learn a little bit more about the decompression theory and play with the decompression software and compare the different models and the light bulb will probably turn on when I'm asleep one night.
Keep reading the paper. After about 5 goes, it's slowly starting to sink in.
Regarding the O2 business, I *thought* that you doubled the deco "segment" times as you got shallower.
So say you had 15 mins on 50% 70-30 feet.
Then you'd have 30 mins on O2, *but* that is from 20 feet to -30 feet of sea water.
Since you only go to 10 feet (or zero I guess) then you halve it down to 15 feet.
And if you had brought a 120 bottle (obviously overkill for 150 dives), it would be 1/2 again from 120 to 70 (but obviously you'd partition the deco differently on a dive like that -- i.e. the 120-70 would be short, the 70-30 shorter than 15 mins and the O2 woudl be "the rest").
However, I'm only trained to use 1 deco gas, so I could be blowing gas of a different kind!
